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000
FXUS61 KBUF 030835
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
435 AM EDT MON AUG 3 2015

.SYNOPSIS...
A COLD FRONT OVER SOUTHERN ONTARIO WILL SLOWLY PUSH ACROSS OUR
FORECAST AREA TODAY WHILE PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. SOME OF THESE STORMS COULD BECOME STRONG TO
SEVERE... ESPECIALLY EAST OF THE GENESEE VALLEY. A SECONDARY
COLD FRONT WILL TOUCH OFF A COUPLE MORE SHOWERS TUESDAY AND
TUESDAY NIGHT...OTHERWISE IT WILL BECOME COOLER AND MORE
COMFORTABLE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
IT WILL BE AN UNSETTLED DAY ACROSS OUR FORECAST AREA TODAY AS A
WAVY FRONTAL BOUNDARY OVER SOUTHERN ONTARIO WILL SLOWLY MAKE ITS
WAY TO THE EAST...GENERATING SHOWERS AND THUNDERSTORMS IN THE
PROCESS. SOME OF THE CONVECTION WILL BECOME STRONG TO SEVERE DURING
THE MIDDAY AND AFTERNOON...WITH THE GREATEST RISK COMING SOUTH AND
EAST OF THE IAG FRONTIER.

A COUPLE WEAK WAVES HAVE ALREADY RIPPLED TO THE NORTHEAST ALONG
THE FRONTAL BOUNDARY...BUT A STRONGER WAVE IN THE VCNTY OF CHICAGO
AT 08Z IS PREVENTING THE FRONT FROM MAKING A STRONGER PUSH TO THE
EAST. THIS WAVE WILL RIDE ALONG THE FRONT AND CROSS THE LOWER
GREAT LAKES DURING THE MORNING HOURS...THUS ALLOWING THE FRONT TO
SURGE A BIT TO OUR WESTERN DOORSTEP BY MIDDAY...BUT GUIDANCE IS
SUGGESTING THAT ADDITIONAL WAVES WILL KEEP THE AFTERNOON
PROGRESSION TO A CRAWL.

DESPITE A FAIR AMOUNT OF MID AND HIGH LEVEL CLOUD COVER...THE
SLOW FRONTAL PASSAGE WILL ENCOURAGE MOST OF OUR FORECAST AREA TO
FURTHER DESTABILIZE. THIS WILL SET THE STAGE FOR STRONG TO SEVERE
CONVECTION LATER TODAY...PARTICULARLY OVER THE SOUTHERN TIER AND
FOR SITES EAST OF THE GENESEE VALLEY. SBCAPES FOR THESE AREAS ARE
FORECAST TO CLIMB TO AN AVERAGE OF 1500-2000 J/KG...WHILE BULK
SHEAR VALUES WILL RANGE FROM 40 TO AS MUCH AS 50 KNOTS. THIS WILL
CERTAINLY SUPPORT WELL ORGANIZED CONVECTION...WITH A GENERAL
UNIDIRECTIONAL FLOW FAVORING BOWING LINE SEGMENTS WITH DAMAGING
STRAIGHT LINE WINDS. ONE CONCERN IS ONE OF THE AFOREMENTIONED SFC
WAVES COULD PASS OVER THE REGION LATER THIS AFTERNOON AND BACK LOW
LEVEL WINDS ENOUGH TO GENERATE AN ISOLATED SUPERCELL OVER THE SRN
TIER OR FINGER LAKES. THIS RISK WOULD BE QUITE LOW...BUT WORTHY OF
KEEPING IN MIND. WILL USE LIKELY POPS TO THE EAST OF THE IAG
FRONTIER WHERE THE STRONGER...MORE WIDESPREAD CONVECTION IS
EXPECTED...WHILE HIGH CHC POPS WILL BE IN PLACE ELSEWHERE.

OTHERWISE IT WILL BE WARM AND HUMID ACROSS THE REGION
TODAY...WITH THE MOST UNCOMFORTABLE CONDITIONS BEING FOUND OVER
THE FINGER LAKES AND EASTERN LAKE ONTARIO REGION WHERE
TEMPERATURES COULD CLIMB INTO THE MID 80S.

THE INITIAL COLD FRONT WILL LIMP TO OUR EAST TONIGHT...WHILE A
SECONDARY COLD FRONT WILL SETTLE ACROSS SOUTHERN ONTARIO TO OUR
DOORSTEP BY DAYBREAK. IT WILL BE THIS SECOND FRONT THAT WILL
ACTUALLY USHER IN A DIFFERENT AIRMASS...AS COOLER AND LESS HUMID
AIR WILL FOLLOW FOR THE REMAINDER OF THE WEEK. IN TERMS OF
PCPN...ANY LEFTOVER SHOWERS FROM THE FIRST FRONTAL BOUNDARY WILL
QUICKLY END DURING THE EVENING HOURS...BUT SHOWERS FROM THE
APPROACHING SECONDARY FRONT COULD BLOSSOM OVER AN INCREASINGLY
UNSTABLE AIRMASS OVER THE WARM WATERS OF LAKE ONTARIO BY DAYBREAK.
THIS IS A HINT OF THINGS TO COME.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
ON TUESDAY...THE AXIS OF THE MAIN UPPER LEVEL TROUGH WILL SETTLE
FROM THE WESTERN GREAT LAKES INTO SOUTHERN ONTARIO...ALONG WITH A
CORRESPONDING SURFACE TROUGH/SECONDARY COLD FRONT. WITH DIURNAL
HEATING OF THE COOLER AIRMASS THAT WILL BE IN PLACE ALOFT AND ONE
OR MORE SHORTWAVE IMPULSES SLIDING THROUGH THE BASE OF THE UPPER
LEVEL TROUGH AND ACROSS OUR REGION...EXPECT ANOTHER ROUND OF
SCATTERED SHOWERS AND THUNDERSTORMS TO AFFECT OUR REGION THROUGH
THE DAY ON TUESDAY. THE BEST POTENTIAL FOR THESE WILL MOST LIKELY
BE FOUND ACROSS THE NORTH COUNTRY AS THIS REGION SHOULD BE MORE
DIRECTLY IMPACTED BY THE PASSING MID AND UPPER LEVEL IMPULSES...
WITH PRECIP CHANCES LARGELY EXHIBITING A GRADUAL DECREASE WITH
INCREASING SOUTHWESTWARD EXTENT. OTHERWISE...THE CONTINUED GRADUAL
BUT STEADY COOL AIR ADVECTION REGIME WILL LEAD TO 850 MB TEMPS
FALLING TO THE +9C TO +12C RANGE BY AFTERNOON...WHICH SHOULD IN
TURN TRANSLATE INTO DAYTIME HIGHS REACHING THE LOWER TO MID 70S IN
MOST PLACES.

DURING TUESDAY NIGHT THE SECONDARY COLD FRONT WILL TRAVERSE OUR
REGION IN CONJUNCTION WITH THE MAIN UPPER LEVEL TROUGH AXIS. WHILE
LINGERING DIURNALLY-DRIVEN SHOWERS AND STORMS AT THE START OF THE
EVENING WILL PROBABLY BE FOLLOWED BY SOME ADDITIONAL SCATTERED
SHOWER ACTIVITY AS THESE FEATURES PASS...IN GENERAL THE LOSS OF
DAYTIME HEATING AND THE ARRIVAL OF DRIER AIR BEHIND THE SECONDARY
FRONT SHOULD LEAD TO PRECIP CHANCES DIMINISHING OVER TIME. THE ONE
EXCEPTION TO THIS WILL BE EAST OF LAKE ONTARIO... WHERE A WESTERLY
FLOW OF PROGRESSIVELY COOLER AIR CROSSING THE WARMER LAKE WATERS
WILL CONTINUE TO GENERATE SCATTERED SHOWERS RIGHT THROUGH THE
NIGHT VIA A COMBINATION OF OROGRAPHIC AND LAKE EFFECT
PROCESSES...AS 850 MB TEMPS WILL FALL TO BETWEEN +7C AND +8C. AS
FOR TEMPERATURES...EXPECT COMFORTABLE CONDITIONS FOR SLEEPING WITH
OVERNIGHT LOWS RANGING FROM THE LOWER TO MID 50S ACROSS INTERIOR
PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO RIGHT AROUND 60
ALONG THE IMMEDIATE LAKESHORES.

ON WEDNESDAY...THE CORE OF THE UPPER LEVEL TROUGH WILL MEANDER
ITS WAY EAST ACROSS QUEBEC PROVINCE...WHILE SURFACE-BASED RIDGING
AND DRIER AIR DRAPED FROM THE WESTERN GREAT LAKES TO THE OHIO
VALLEY BUILDS EASTWARD INTO THE CENTRAL GREAT LAKES. WHILE THE
LATTER SHOULD RESULT IN A MAINLY DRY DAY FOR MOST AREAS SOUTH OF
LAKE ONTARIO...THE FAR NORTHEASTERN FINGER LAKES REGION AND NORTH
CENTRAL NEW YORK WILL BE SUBJECT TO SOME ADDITIONAL SCATTERED LAKE
AND OROGRAPHICALLY-DRIVEN SHOWERS EARLY WEDNESDAY...FOLLOWED BY
MORE GENERAL DIURNALLY-DRIVEN SHOWERS THE BALANCE OF THE DAY AS
ANOTHER SHORTWAVE SWINGS THROUGH THE BASE OF THE UPPER TROUGH IN
CONJUNCTION WITH RENEWED DAYTIME HEATING. ALL OF THIS SHOULD THEN
QUICKLY WIND DOWN WEDNESDAY NIGHT WITH THE LOSS OF HEATING AND AS
THE AFOREMENTIONED RIDGE BUILDS DIRECTLY OVERHEAD... RESULTING IN
A RETURN TO DRY WEATHER AREAWIDE TO CLOSE OUT THE SHORT TERM
PERIOD.

WITH RESPECT TO TEMPERATURES WEDNESDAY AND WEDNESDAY NIGHT...THESE
SHOULD REMAIN SOLIDLY BELOW NORMAL...AND SHOULD IN FACT BOTTOM OUT
FOR THE WEEK AS OUR AIRMASS REACHES ITS COOLEST OVERALL POINT OF
THE NEXT SEVEN DAYS. 850 MB TEMPS OF ROUGHLY +7C TO +10C SHOULD
TRANSLATE INTO HIGHS MOSTLY IN THE UPPER 60S TO LOWER 70S ON
WEDNESDAY...WITH THE COOLEST READINGS ACROSS THE HIGHER
TERRAIN...AND THE WARMEST OVERALL TEMPS FOUND IN THE GENESEE
VALLEY/WESTERN FINGER LAKES... WHERE A FEW SPOTS COULD STILL REACH
THE MID 70S. SUCH READINGS WILL THEN BE FOLLOWED BY LOWS RANGING
THROUGH THE 50S WEDNESDAY NIGHT... WHEN THE COOLEST INTERIOR
PORTIONS OF THE SOUTHERN TIER AND NORTH COUNTRY COULD TICKLE THE
50 DEGREE MARK.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
IN THE LONGER TERM PORTION OF THE FORECAST...THE MID AND UPPER
LEVEL FLOW ACROSS OUR REGION WILL TEND TO GRADUALLY DEAMPLIFY
THROUGH THE LATTER PORTIONS OF THE WORK WEEK AND INTO THE FIRST
PART OF THE UPCOMING WEEKEND AS THE CORE OF THIS WEEK/S MAIN UPPER
TROUGH LIFTS OUT INTO THE NORTHERN ATLANTIC...AND MAY EVEN BRIEFLY
GO QUASI-ZONAL BEFORE A VERY MODEST MID-LEVEL TROUGH APPROACHES
OUR REGION IN TIME FOR SUNDAY. AS A RESULT...INITIALLY BELOW
NORMAL TEMPERATURES LATE IN THE WORK WEEK SHOULD TREND CLOSER TO
SEASONAL AVERAGES BY NEXT WEEKEND. MORE SPECIFICALLY...DAYTIME
HIGHS INITIALLY IN THE LOWER TO MID 70S ON THURSDAY SHOULD CLIMB
BACK INTO THE MID AND UPPER 70S FOR NEXT WEEKEND...WHILE NIGHTTIME
LOWS INITIALLY RANGING THROUGH THE 50S SHOULD SLOWLY MODERATE INTO
THE 55-60 RANGE.

AS FOR PRECIPITATION CHANCES...MAINLY DRY WEATHER SHOULD PREVAIL
THURSDAY THROUGH SATURDAY AS EXPANSIVE CANADIAN HIGH PRESSURE
DRAPED FROM ONTARIO PROVINCE TO THE UPPER OHIO VALLEY AT THE START
OF THE PERIOD SLOWLY DRIFTS EASTWARD INTO QUEBEC...AND KEEPS THE
MAIN SURFACE FRONTAL ZONE/ANY ATTENDANT WAVES OF LOW PRESSURE
SUPPRESSED TO OUR SOUTH. AFTER THAT...THE AFOREMENTIONED MID-LEVEL
TROUGH SHOULD PROVIDE ENOUGH OF AN INCREASE IN MOISTURE AND
SYNOPTIC- SCALE LIFT TO RESULT IN LIMITED CHANCES FOR
SHOWERS/THUNDERSTORMS RETURNING ON SUNDAY...WHICH AT THIS DISTANT
VANTAGE POINT WILL BE COVERED WITH SOME VERY LOW CHANCE POPS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY AFFECTING THE
KJHW... KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 08Z WILL REMAIN IN PLACE
THROUGH AT LEAST MIDDAY. FOR THIS AFTERNOON...WHILE VFR CIGS ARE
ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS WILL BE
FOUND IN AND NEAR CONVECTION.

TONIGHT...VFR CONDITIONS WILL BE FOUND ACROSS THE MAJORITY OF THE
REGION. THE EXCEPTION COULD BE ACROSS THE SOUTHERN TIER WHERE MVFR
CIGS COULD DEVELOP AFTER MIDNIGHT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES
AT KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO
POSSIBLE AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
A RELATIVELY TIGHT SFC PRESSURE GRADIENT WILL COMBINE WITH A
STRONG LOW LEVEL JET AHEAD OF A COLD FRONT TO PRODUCE GUSTY WINDS
ACROSS THE LOWER GREAT LAKES TODAY. A SMALL CRAFT ADVISORY IS
ALREADY IN PLACE FOR ALL OF THE NEW YORK NEARSHORE WATERS...AS
WELL AS BUF HARBOR...FOR WINDS THAT COULD GUST TO 30 KNOTS. THIS
WILL ESPECIALLY BE THE CASE ON LAKE ERIE. THE WINDS WILL DROP OFF
LATER THIS AFTERNOON AND EVENING IN THE WAKE OF A SLOW MOVING COLD
FRONT.

THE COLD FRONT WILL LIKELY GENERATE SOME SHOWERS AND
THUNDERSTORMS...ESPECIALLY OVER THE EASTERN HALF OF LAKE ONTARIO
WHERE THE STORMS COULD BECOME QUITE STRONG. MARINERS THROUGHOUT
THE LOWER GREAT LAKES SHOULD BE ALERT FOR POSSIBLE MARINE WARNINGS
THROUGHOUT THE DAY.

WINDS WILL DROP BELOW SMALL CRAFT ADVISORY LEVELS THIS EVENING
AND REMAIN RELATIVELY LIGHT DURING THE OVERNIGHT HOURS. THESE
WINDS WILL FRESHEN AGAIN ON TUESDAY AS ANOTHER FRONTAL BOUNDARY
WILL PUSH SOUTH ACROSS THE LOWER GREAT LAKES. THIS WILL ENCOURAGE
WAVES TO BUILD TO 3 TO 5 FEET...WITH ANOTHER ROUND OF SMALL CRAFT
ADVISORIES LIKELY FOR THE NEARSHORE WATERS OF LAKE ERIE AND
POSSIBLY FOR THE EASTERN END OF LAKE ONTARIO.

A FALL LIKE AIRMASS IN THE WAKE OF THIS SECOND COLD FRONT COULD
SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND
WEDNESDAY. WILL CARRY SLIGHT CHC FOR SPOUTS IN THE GRIDDED DATA
BASE FOR NOW. STAY TUNED.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ042>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 030835
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
435 AM EDT MON AUG 3 2015

.SYNOPSIS...
A COLD FRONT OVER SOUTHERN ONTARIO WILL SLOWLY PUSH ACROSS OUR
FORECAST AREA TODAY WHILE PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. SOME OF THESE STORMS COULD BECOME STRONG TO
SEVERE... ESPECIALLY EAST OF THE GENESEE VALLEY. A SECONDARY
COLD FRONT WILL TOUCH OFF A COUPLE MORE SHOWERS TUESDAY AND
TUESDAY NIGHT...OTHERWISE IT WILL BECOME COOLER AND MORE
COMFORTABLE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
IT WILL BE AN UNSETTLED DAY ACROSS OUR FORECAST AREA TODAY AS A
WAVY FRONTAL BOUNDARY OVER SOUTHERN ONTARIO WILL SLOWLY MAKE ITS
WAY TO THE EAST...GENERATING SHOWERS AND THUNDERSTORMS IN THE
PROCESS. SOME OF THE CONVECTION WILL BECOME STRONG TO SEVERE DURING
THE MIDDAY AND AFTERNOON...WITH THE GREATEST RISK COMING SOUTH AND
EAST OF THE IAG FRONTIER.

A COUPLE WEAK WAVES HAVE ALREADY RIPPLED TO THE NORTHEAST ALONG
THE FRONTAL BOUNDARY...BUT A STRONGER WAVE IN THE VCNTY OF CHICAGO
AT 08Z IS PREVENTING THE FRONT FROM MAKING A STRONGER PUSH TO THE
EAST. THIS WAVE WILL RIDE ALONG THE FRONT AND CROSS THE LOWER
GREAT LAKES DURING THE MORNING HOURS...THUS ALLOWING THE FRONT TO
SURGE A BIT TO OUR WESTERN DOORSTEP BY MIDDAY...BUT GUIDANCE IS
SUGGESTING THAT ADDITIONAL WAVES WILL KEEP THE AFTERNOON
PROGRESSION TO A CRAWL.

DESPITE A FAIR AMOUNT OF MID AND HIGH LEVEL CLOUD COVER...THE
SLOW FRONTAL PASSAGE WILL ENCOURAGE MOST OF OUR FORECAST AREA TO
FURTHER DESTABILIZE. THIS WILL SET THE STAGE FOR STRONG TO SEVERE
CONVECTION LATER TODAY...PARTICULARLY OVER THE SOUTHERN TIER AND
FOR SITES EAST OF THE GENESEE VALLEY. SBCAPES FOR THESE AREAS ARE
FORECAST TO CLIMB TO AN AVERAGE OF 1500-2000 J/KG...WHILE BULK
SHEAR VALUES WILL RANGE FROM 40 TO AS MUCH AS 50 KNOTS. THIS WILL
CERTAINLY SUPPORT WELL ORGANIZED CONVECTION...WITH A GENERAL
UNIDIRECTIONAL FLOW FAVORING BOWING LINE SEGMENTS WITH DAMAGING
STRAIGHT LINE WINDS. ONE CONCERN IS ONE OF THE AFOREMENTIONED SFC
WAVES COULD PASS OVER THE REGION LATER THIS AFTERNOON AND BACK LOW
LEVEL WINDS ENOUGH TO GENERATE AN ISOLATED SUPERCELL OVER THE SRN
TIER OR FINGER LAKES. THIS RISK WOULD BE QUITE LOW...BUT WORTHY OF
KEEPING IN MIND. WILL USE LIKELY POPS TO THE EAST OF THE IAG
FRONTIER WHERE THE STRONGER...MORE WIDESPREAD CONVECTION IS
EXPECTED...WHILE HIGH CHC POPS WILL BE IN PLACE ELSEWHERE.

OTHERWISE IT WILL BE WARM AND HUMID ACROSS THE REGION
TODAY...WITH THE MOST UNCOMFORTABLE CONDITIONS BEING FOUND OVER
THE FINGER LAKES AND EASTERN LAKE ONTARIO REGION WHERE
TEMPERATURES COULD CLIMB INTO THE MID 80S.

THE INITIAL COLD FRONT WILL LIMP TO OUR EAST TONIGHT...WHILE A
SECONDARY COLD FRONT WILL SETTLE ACROSS SOUTHERN ONTARIO TO OUR
DOORSTEP BY DAYBREAK. IT WILL BE THIS SECOND FRONT THAT WILL
ACTUALLY USHER IN A DIFFERENT AIRMASS...AS COOLER AND LESS HUMID
AIR WILL FOLLOW FOR THE REMAINDER OF THE WEEK. IN TERMS OF
PCPN...ANY LEFTOVER SHOWERS FROM THE FIRST FRONTAL BOUNDARY WILL
QUICKLY END DURING THE EVENING HOURS...BUT SHOWERS FROM THE
APPROACHING SECONDARY FRONT COULD BLOSSOM OVER AN INCREASINGLY
UNSTABLE AIRMASS OVER THE WARM WATERS OF LAKE ONTARIO BY DAYBREAK.
THIS IS A HINT OF THINGS TO COME.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
ON TUESDAY...THE AXIS OF THE MAIN UPPER LEVEL TROUGH WILL SETTLE
FROM THE WESTERN GREAT LAKES INTO SOUTHERN ONTARIO...ALONG WITH A
CORRESPONDING SURFACE TROUGH/SECONDARY COLD FRONT. WITH DIURNAL
HEATING OF THE COOLER AIRMASS THAT WILL BE IN PLACE ALOFT AND ONE
OR MORE SHORTWAVE IMPULSES SLIDING THROUGH THE BASE OF THE UPPER
LEVEL TROUGH AND ACROSS OUR REGION...EXPECT ANOTHER ROUND OF
SCATTERED SHOWERS AND THUNDERSTORMS TO AFFECT OUR REGION THROUGH
THE DAY ON TUESDAY. THE BEST POTENTIAL FOR THESE WILL MOST LIKELY
BE FOUND ACROSS THE NORTH COUNTRY AS THIS REGION SHOULD BE MORE
DIRECTLY IMPACTED BY THE PASSING MID AND UPPER LEVEL IMPULSES...
WITH PRECIP CHANCES LARGELY EXHIBITING A GRADUAL DECREASE WITH
INCREASING SOUTHWESTWARD EXTENT. OTHERWISE...THE CONTINUED GRADUAL
BUT STEADY COOL AIR ADVECTION REGIME WILL LEAD TO 850 MB TEMPS
FALLING TO THE +9C TO +12C RANGE BY AFTERNOON...WHICH SHOULD IN
TURN TRANSLATE INTO DAYTIME HIGHS REACHING THE LOWER TO MID 70S IN
MOST PLACES.

DURING TUESDAY NIGHT THE SECONDARY COLD FRONT WILL TRAVERSE OUR
REGION IN CONJUNCTION WITH THE MAIN UPPER LEVEL TROUGH AXIS. WHILE
LINGERING DIURNALLY-DRIVEN SHOWERS AND STORMS AT THE START OF THE
EVENING WILL PROBABLY BE FOLLOWED BY SOME ADDITIONAL SCATTERED
SHOWER ACTIVITY AS THESE FEATURES PASS...IN GENERAL THE LOSS OF
DAYTIME HEATING AND THE ARRIVAL OF DRIER AIR BEHIND THE SECONDARY
FRONT SHOULD LEAD TO PRECIP CHANCES DIMINISHING OVER TIME. THE ONE
EXCEPTION TO THIS WILL BE EAST OF LAKE ONTARIO... WHERE A WESTERLY
FLOW OF PROGRESSIVELY COOLER AIR CROSSING THE WARMER LAKE WATERS
WILL CONTINUE TO GENERATE SCATTERED SHOWERS RIGHT THROUGH THE
NIGHT VIA A COMBINATION OF OROGRAPHIC AND LAKE EFFECT
PROCESSES...AS 850 MB TEMPS WILL FALL TO BETWEEN +7C AND +8C. AS
FOR TEMPERATURES...EXPECT COMFORTABLE CONDITIONS FOR SLEEPING WITH
OVERNIGHT LOWS RANGING FROM THE LOWER TO MID 50S ACROSS INTERIOR
PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO RIGHT AROUND 60
ALONG THE IMMEDIATE LAKESHORES.

ON WEDNESDAY...THE CORE OF THE UPPER LEVEL TROUGH WILL MEANDER
ITS WAY EAST ACROSS QUEBEC PROVINCE...WHILE SURFACE-BASED RIDGING
AND DRIER AIR DRAPED FROM THE WESTERN GREAT LAKES TO THE OHIO
VALLEY BUILDS EASTWARD INTO THE CENTRAL GREAT LAKES. WHILE THE
LATTER SHOULD RESULT IN A MAINLY DRY DAY FOR MOST AREAS SOUTH OF
LAKE ONTARIO...THE FAR NORTHEASTERN FINGER LAKES REGION AND NORTH
CENTRAL NEW YORK WILL BE SUBJECT TO SOME ADDITIONAL SCATTERED LAKE
AND OROGRAPHICALLY-DRIVEN SHOWERS EARLY WEDNESDAY...FOLLOWED BY
MORE GENERAL DIURNALLY-DRIVEN SHOWERS THE BALANCE OF THE DAY AS
ANOTHER SHORTWAVE SWINGS THROUGH THE BASE OF THE UPPER TROUGH IN
CONJUNCTION WITH RENEWED DAYTIME HEATING. ALL OF THIS SHOULD THEN
QUICKLY WIND DOWN WEDNESDAY NIGHT WITH THE LOSS OF HEATING AND AS
THE AFOREMENTIONED RIDGE BUILDS DIRECTLY OVERHEAD... RESULTING IN
A RETURN TO DRY WEATHER AREAWIDE TO CLOSE OUT THE SHORT TERM
PERIOD.

WITH RESPECT TO TEMPERATURES WEDNESDAY AND WEDNESDAY NIGHT...THESE
SHOULD REMAIN SOLIDLY BELOW NORMAL...AND SHOULD IN FACT BOTTOM OUT
FOR THE WEEK AS OUR AIRMASS REACHES ITS COOLEST OVERALL POINT OF
THE NEXT SEVEN DAYS. 850 MB TEMPS OF ROUGHLY +7C TO +10C SHOULD
TRANSLATE INTO HIGHS MOSTLY IN THE UPPER 60S TO LOWER 70S ON
WEDNESDAY...WITH THE COOLEST READINGS ACROSS THE HIGHER
TERRAIN...AND THE WARMEST OVERALL TEMPS FOUND IN THE GENESEE
VALLEY/WESTERN FINGER LAKES... WHERE A FEW SPOTS COULD STILL REACH
THE MID 70S. SUCH READINGS WILL THEN BE FOLLOWED BY LOWS RANGING
THROUGH THE 50S WEDNESDAY NIGHT... WHEN THE COOLEST INTERIOR
PORTIONS OF THE SOUTHERN TIER AND NORTH COUNTRY COULD TICKLE THE
50 DEGREE MARK.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
IN THE LONGER TERM PORTION OF THE FORECAST...THE MID AND UPPER
LEVEL FLOW ACROSS OUR REGION WILL TEND TO GRADUALLY DEAMPLIFY
THROUGH THE LATTER PORTIONS OF THE WORK WEEK AND INTO THE FIRST
PART OF THE UPCOMING WEEKEND AS THE CORE OF THIS WEEK/S MAIN UPPER
TROUGH LIFTS OUT INTO THE NORTHERN ATLANTIC...AND MAY EVEN BRIEFLY
GO QUASI-ZONAL BEFORE A VERY MODEST MID-LEVEL TROUGH APPROACHES
OUR REGION IN TIME FOR SUNDAY. AS A RESULT...INITIALLY BELOW
NORMAL TEMPERATURES LATE IN THE WORK WEEK SHOULD TREND CLOSER TO
SEASONAL AVERAGES BY NEXT WEEKEND. MORE SPECIFICALLY...DAYTIME
HIGHS INITIALLY IN THE LOWER TO MID 70S ON THURSDAY SHOULD CLIMB
BACK INTO THE MID AND UPPER 70S FOR NEXT WEEKEND...WHILE NIGHTTIME
LOWS INITIALLY RANGING THROUGH THE 50S SHOULD SLOWLY MODERATE INTO
THE 55-60 RANGE.

AS FOR PRECIPITATION CHANCES...MAINLY DRY WEATHER SHOULD PREVAIL
THURSDAY THROUGH SATURDAY AS EXPANSIVE CANADIAN HIGH PRESSURE
DRAPED FROM ONTARIO PROVINCE TO THE UPPER OHIO VALLEY AT THE START
OF THE PERIOD SLOWLY DRIFTS EASTWARD INTO QUEBEC...AND KEEPS THE
MAIN SURFACE FRONTAL ZONE/ANY ATTENDANT WAVES OF LOW PRESSURE
SUPPRESSED TO OUR SOUTH. AFTER THAT...THE AFOREMENTIONED MID-LEVEL
TROUGH SHOULD PROVIDE ENOUGH OF AN INCREASE IN MOISTURE AND
SYNOPTIC- SCALE LIFT TO RESULT IN LIMITED CHANCES FOR
SHOWERS/THUNDERSTORMS RETURNING ON SUNDAY...WHICH AT THIS DISTANT
VANTAGE POINT WILL BE COVERED WITH SOME VERY LOW CHANCE POPS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY AFFECTING THE
KJHW... KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 08Z WILL REMAIN IN PLACE
THROUGH AT LEAST MIDDAY. FOR THIS AFTERNOON...WHILE VFR CIGS ARE
ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS WILL BE
FOUND IN AND NEAR CONVECTION.

TONIGHT...VFR CONDITIONS WILL BE FOUND ACROSS THE MAJORITY OF THE
REGION. THE EXCEPTION COULD BE ACROSS THE SOUTHERN TIER WHERE MVFR
CIGS COULD DEVELOP AFTER MIDNIGHT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES
AT KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO
POSSIBLE AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
A RELATIVELY TIGHT SFC PRESSURE GRADIENT WILL COMBINE WITH A
STRONG LOW LEVEL JET AHEAD OF A COLD FRONT TO PRODUCE GUSTY WINDS
ACROSS THE LOWER GREAT LAKES TODAY. A SMALL CRAFT ADVISORY IS
ALREADY IN PLACE FOR ALL OF THE NEW YORK NEARSHORE WATERS...AS
WELL AS BUF HARBOR...FOR WINDS THAT COULD GUST TO 30 KNOTS. THIS
WILL ESPECIALLY BE THE CASE ON LAKE ERIE. THE WINDS WILL DROP OFF
LATER THIS AFTERNOON AND EVENING IN THE WAKE OF A SLOW MOVING COLD
FRONT.

THE COLD FRONT WILL LIKELY GENERATE SOME SHOWERS AND
THUNDERSTORMS...ESPECIALLY OVER THE EASTERN HALF OF LAKE ONTARIO
WHERE THE STORMS COULD BECOME QUITE STRONG. MARINERS THROUGHOUT
THE LOWER GREAT LAKES SHOULD BE ALERT FOR POSSIBLE MARINE WARNINGS
THROUGHOUT THE DAY.

WINDS WILL DROP BELOW SMALL CRAFT ADVISORY LEVELS THIS EVENING
AND REMAIN RELATIVELY LIGHT DURING THE OVERNIGHT HOURS. THESE
WINDS WILL FRESHEN AGAIN ON TUESDAY AS ANOTHER FRONTAL BOUNDARY
WILL PUSH SOUTH ACROSS THE LOWER GREAT LAKES. THIS WILL ENCOURAGE
WAVES TO BUILD TO 3 TO 5 FEET...WITH ANOTHER ROUND OF SMALL CRAFT
ADVISORIES LIKELY FOR THE NEARSHORE WATERS OF LAKE ERIE AND
POSSIBLY FOR THE EASTERN END OF LAKE ONTARIO.

A FALL LIKE AIRMASS IN THE WAKE OF THIS SECOND COLD FRONT COULD
SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND
WEDNESDAY. WILL CARRY SLIGHT CHC FOR SPOUTS IN THE GRIDDED DATA
BASE FOR NOW. STAY TUNED.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ042>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH




000
FXUS61 KBUF 030827
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
427 AM EDT MON AUG 3 2015

.SYNOPSIS...
A COLD FRONT OVER SOUTHERN ONTARIO WILL SLOWLY PUSH ACROSS OUR
FORECAST AREA TODAY WHILE PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. SOME OF THESE STORMS COULD BECOME STRONG TO
SEVERE... ESPECIALLY EAST OF THE GENESEE VALLEY. A SECONDARY
COLD FRONT WILL TOUCH OFF A COUPLE MORE SHOWERS TUESDAY AND
TUESDAY NIGHT...OTHERWISE IT WILL BECOME COOLER AND MORE
COMFORTABLE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
IT WILL BE AN UNSETTLED DAY ACROSS OUR FORECAST AREA TODAY AS A
WAVY FRONTAL BOUNDARY OVER SOUTHERN ONTARIO WILL SLOWLY MAKE ITS
TO THE EAST...GENERATING SHOWERS AND THUNDERSTORMS IN THE PROCESS.
SOME OF THE CONVECTION WILL BECOME STRONG TO SEVERE DURING THE
MIDDAY AND AFTERNOON...WITH THE GREATEST RISK COMING SOUTH AND
EAST OF THE IAG FRONTIER.

A COUPLE WEAK WAVES HAVE ALREADY RIPPLED TO THE NORTHEAST ALONG
THE FRONTAL BOUNDARY...BUT A STRONGER WAVE IN THE VCNTY OF CHICAGO
AT 08Z IS PREVENTING THE FRONT FROM MAKING A STRONGER PUSH TO THE
EAST. THIS WAVE WILL RIDE ALONG THE FRONT AND CROSS THE LOWER
GREAT LAKES DURING THE MORNING HOURS...THUS ALLOWING THE FRONT TO
SURGE A BIT TO OUR WESTERN DOORSTEP BY MIDDAY...BUT GUIDANCE IS
SUGGESTING THAT ADDITIONAL WAVES WILL KEEP THE AFTERNOON
PROGRESSION TO A CRAWL.

DESPITE A FAIR AMOUNT OF MID AND HIGH LEVEL CLOUD COVER...THE
SLOW FRONTAL PASSAGE WILL ENCOURAGE MOST OF OUR FORECAST AREA TO
FURTHER DESTABILIZE. THIS WILL SET THE STAGE FOR STRONG TO SEVERE
CONVECTION LATER TODAY...PARTICULARLY OVER THE SOUTHERN TIER AND
FOR SITES EAST OF THE GENESEE VALLEY. SBCAPES FOR THESE AREAS ARE
FORECAST TO CLIMB TO AN AVERAGE OF 1500-2000 J/KG...WHILE BULK
SHEAR VALUES WILL RANGE FROM 40 TO AS MUCH AS 50 KNOTS. THIS WILL
CERTAINLY SUPPORT WELL ORGANIZED CONVECTION...WITH A GENERAL
UNIDIRECTIONAL FLOW FAVORING BOWING LINE SEGMENTS WITH DAMAGING
STRAIGHT LINE WINDS. ONE CONCERN IS ONE OF THE AFOREMENTIONED SFC
WAVES COULD PASS OVER THE REGION LATER THIS AFTERNOON AND BACK LOW
LEVEL WINDS ENOUGH TO GENERATE AN ISOLATED SUPERCELL OVER THE SRN
TIER OR FINGER LAKES. THIS RISK WOULD BE QUITE LOW...BUT WORTHY OF
KEEPING IN MIND. WILL USE LIKELY POPS TO THE EAST OF THE IAG
FRONTIER WHERE THE STRONGER...MORE WIDESPREAD CONVECTION IS
EXPECTED...WHILE HIGH CHC POPS WILL BE IN PLACE ELSEWHERE.

OTHERWISE IT WILL BE WARM AND HUMID ACROSS THE REGION
TODAY...WITH THE MOST UNCOMFORTABLE CONDITIONS BEING FOUND OVER
THE FINGER LAKES AND EASTERN LAKE ONTARIO REGION WHERE
TEMPERATURES COULD CLIMB INTO THE MID 80S.

THE INITIAL COLD FRONT WILL LIMP TO OUR EAST TONIGHT...WHILE A
SECONDARY COLD FRONT WILL SETTLE ACROSS SOUTHERN ONTARIO TO OUR
DOORSTEP BY DAYBREAK. IT WILL BE THIS SECOND FRONT THAT WILL
ACTUALLY USHER IN A DIFFERENT AIRMASS...AS COOLER AND LESS HUMID
AIR WILL FOLLOW FOR THE REMAINDER OF THE WEEK. IN TERMS OF
PCPN...ANY LEFTOVER SHOWERS FROM THE FIRST FRONTAL BOUNDARY WILL
QUICKLY END DURING THE EVENING HOURS...BUT SHOWERS FROM THE
APPROACHING SECONDARY FRONT COULD BLOSSOM OVER AN INCREASINGLY
UNSTABLE AIRMASS OVER THE WARM WATERS OF LAKE ONTARIO BY DAYBREAK.
THIS IS A HINT OF THINGS TO COME.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
ON TUESDAY...THE AXIS OF THE MAIN UPPER LEVEL TROUGH WILL SETTLE
FROM THE WESTERN GREAT LAKES INTO SOUTHERN ONTARIO...ALONG WITH A
CORRESPONDING SURFACE TROUGH/SECONDARY COLD FRONT. WITH DIURNAL
HEATING OF THE COOLER AIRMASS THAT WILL BE IN PLACE ALOFT AND ONE
OR MORE SHORTWAVE IMPULSES SLIDING THROUGH THE BASE OF THE UPPER
LEVEL TROUGH AND ACROSS OUR REGION...EXPECT ANOTHER ROUND OF
SCATTERED SHOWERS AND THUNDERSTORMS TO AFFECT OUR REGION THROUGH
THE DAY ON TUESDAY. THE BEST POTENTIAL FOR THESE WILL MOST LIKELY
BE FOUND ACROSS THE NORTH COUNTRY AS THIS REGION SHOULD BE MORE
DIRECTLY IMPACTED BY THE PASSING MID AND UPPER LEVEL IMPULSES...
WITH PRECIP CHANCES LARGELY EXHIBITING A GRADUAL DECREASE WITH
INCREASING SOUTHWESTWARD EXTENT. OTHERWISE...THE CONTINUED GRADUAL
BUT STEADY COOL AIR ADVECTION REGIME WILL LEAD TO 850 MB TEMPS
FALLING TO THE +9C TO +12C RANGE BY AFTERNOON...WHICH SHOULD IN
TURN TRANSLATE INTO DAYTIME HIGHS REACHING THE LOWER TO MID 70S IN
MOST PLACES.

DURING TUESDAY NIGHT THE SECONDARY COLD FRONT WILL TRAVERSE OUR
REGION IN CONJUNCTION WITH THE MAIN UPPER LEVEL TROUGH AXIS. WHILE
LINGERING DIURNALLY-DRIVEN SHOWERS AND STORMS AT THE START OF THE
EVENING WILL PROBABLY BE FOLLOWED BY SOME ADDITIONAL SCATTERED
SHOWER ACTIVITY AS THESE FEATURES PASS...IN GENERAL THE LOSS OF
DAYTIME HEATING AND THE ARRIVAL OF DRIER AIR BEHIND THE SECONDARY
FRONT SHOULD LEAD TO PRECIP CHANCES DIMINISHING OVER TIME. THE ONE
EXCEPTION TO THIS WILL BE EAST OF LAKE ONTARIO... WHERE A WESTERLY
FLOW OF PROGRESSIVELY COOLER AIR CROSSING THE WARMER LAKE WATERS
WILL CONTINUE TO GENERATE SCATTERED SHOWERS RIGHT THROUGH THE
NIGHT VIA A COMBINATION OF OROGRAPHIC AND LAKE EFFECT
PROCESSES...AS 850 MB TEMPS WILL FALL TO BETWEEN +7C AND +8C. AS
FOR TEMPERATURES...EXPECT COMFORTABLE CONDITIONS FOR SLEEPING WITH
OVERNIGHT LOWS RANGING FROM THE LOWER TO MID 50S ACROSS INTERIOR
PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO RIGHT AROUND 60
ALONG THE IMMEDIATE LAKESHORES.

ON WEDNESDAY...THE CORE OF THE UPPER LEVEL TROUGH WILL MEANDER
ITS WAY EAST ACROSS QUEBEC PROVINCE...WHILE SURFACE-BASED RIDGING
AND DRIER AIR DRAPED FROM THE WESTERN GREAT LAKES TO THE OHIO
VALLEY BUILDS EASTWARD INTO THE CENTRAL GREAT LAKES. WHILE THE
LATTER SHOULD RESULT IN A MAINLY DRY DAY FOR MOST AREAS SOUTH OF
LAKE ONTARIO...THE FAR NORTHEASTERN FINGER LAKES REGION AND NORTH
CENTRAL NEW YORK WILL BE SUBJECT TO SOME ADDITIONAL SCATTERED LAKE
AND OROGRAPHICALLY-DRIVEN SHOWERS EARLY WEDNESDAY...FOLLOWED BY
MORE GENERAL DIURNALLY-DRIVEN SHOWERS THE BALANCE OF THE DAY AS
ANOTHER SHORTWAVE SWINGS THROUGH THE BASE OF THE UPPER TROUGH IN
CONJUNCTION WITH RENEWED DAYTIME HEATING. ALL OF THIS SHOULD THEN
QUICKLY WIND DOWN WEDNESDAY NIGHT WITH THE LOSS OF HEATING AND AS
THE AFOREMENTIONED RIDGE BUILDS DIRECTLY OVERHEAD... RESULTING IN
A RETURN TO DRY WEATHER AREAWIDE TO CLOSE OUT THE SHORT TERM
PERIOD.

WITH RESPECT TO TEMPERATURES WEDNESDAY AND WEDNESDAY NIGHT...THESE
SHOULD REMAIN SOLIDLY BELOW NORMAL...AND SHOULD IN FACT BOTTOM OUT
FOR THE WEEK AS OUR AIRMASS REACHES ITS COOLEST OVERALL POINT OF
THE NEXT SEVEN DAYS. 850 MB TEMPS OF ROUGHLY +7C TO +10C SHOULD
TRANSLATE INTO HIGHS MOSTLY IN THE UPPER 60S TO LOWER 70S ON
WEDNESDAY...WITH THE COOLEST READINGS ACROSS THE HIGHER
TERRAIN...AND THE WARMEST OVERALL TEMPS FOUND IN THE GENESEE
VALLEY/WESTERN FINGER LAKES... WHERE A FEW SPOTS COULD STILL REACH
THE MID 70S. SUCH READINGS WILL THEN BE FOLLOWED BY LOWS RANGING
THROUGH THE 50S WEDNESDAY NIGHT... WHEN THE COOLEST INTERIOR
PORTIONS OF THE SOUTHERN TIER AND NORTH COUNTRY COULD TICKLE THE
50 DEGREE MARK.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
IN THE LONGER TERM PORTION OF THE FORECAST...THE MID AND UPPER
LEVEL FLOW ACROSS OUR REGION WILL TEND TO GRADUALLY DEAMPLIFY
THROUGH THE LATTER PORTIONS OF THE WORK WEEK AND INTO THE FIRST
PART OF THE UPCOMING WEEKEND AS THE CORE OF THIS WEEK/S MAIN UPPER
TROUGH LIFTS OUT INTO THE NORTHERN ATLANTIC...AND MAY EVEN BRIEFLY
GO QUASI-ZONAL BEFORE A VERY MODEST MID-LEVEL TROUGH APPROACHES
OUR REGION IN TIME FOR SUNDAY. AS A RESULT...INITIALLY BELOW
NORMAL TEMPERATURES LATE IN THE WORK WEEK SHOULD TREND CLOSER TO
SEASONAL AVERAGES BY NEXT WEEKEND. MORE SPECIFICALLY...DAYTIME
HIGHS INITIALLY IN THE LOWER TO MID 70S ON THURSDAY SHOULD CLIMB
BACK INTO THE MID AND UPPER 70S FOR NEXT WEEKEND...WHILE NIGHTTIME
LOWS INITIALLY RANGING THROUGH THE 50S SHOULD SLOWLY MODERATE INTO
THE 55-60 RANGE.

AS FOR PRECIPITATION CHANCES...MAINLY DRY WEATHER SHOULD PREVAIL
THURSDAY THROUGH SATURDAY AS EXPANSIVE CANADIAN HIGH PRESSURE
DRAPED FROM ONTARIO PROVINCE TO THE UPPER OHIO VALLEY AT THE START
OF THE PERIOD SLOWLY DRIFTS EASTWARD INTO QUEBEC...AND KEEPS THE
MAIN SURFACE FRONTAL ZONE/ANY ATTENDANT WAVES OF LOW PRESSURE
SUPPRESSED TO OUR SOUTH. AFTER THAT...THE AFOREMENTIONED MID-LEVEL
TROUGH SHOULD PROVIDE ENOUGH OF AN INCREASE IN MOISTURE AND
SYNOPTIC- SCALE LIFT TO RESULT IN LIMITED CHANCES FOR
SHOWERS/THUNDERSTORMS RETURNING ON SUNDAY...WHICH AT THIS DISTANT
VANTAGE POINT WILL BE COVERED WITH SOME VERY LOW CHANCE POPS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY AFFECTING THE
KJHW... KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 08Z WILL REMAIN IN PLACE
THROUGH AT LEAST MIDDAY. FOR THIS AFTERNOON...WHILE VFR CIGS ARE
ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS WILL BE
FOUND IN AND NEAR CONVECTION.

TONIGHT...VFR CONDITIONS WILL BE FOUND ACROSS THE MAJORITY OF THE
REGION. THE EXCEPTION COULD BE ACROSS THE SOUTHERN TIER WHERE MVFR
CIGS COULD DEVELOP AFTER MIDNIGHT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES
AT KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO
POSSIBLE AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
A RELATIVELY TIGHT SFC PRESSURE GRADIENT WILL COMBINE WITH A
STRONG LOW LEVEL JET AHEAD OF A COLD FRONT TO PRODUCE GUSTY WINDS
ACROSS THE LOWER GREAT LAKES TODAY. A SMALL CRAFT ADVISORY IS
ALREADY IN PLACE FOR ALL OF THE NEW YORK NEARSHORE WATERS...AS
WELL AS BUF HARBOR...FOR WINDS THAT COULD GUST TO 30 KNOTS. THIS
WILL ESPECIALLY BE THE CASE ON LAKE ERIE. THE WINDS WILL DROP OFF
LATER THIS AFTERNOON AND EVENING IN THE WAKE OF A SLOW MOVING COLD
FRONT.

THE COLD FRONT WILL LIKELY GENERATE SOME SHOWERS AND
THUNDERSTORMS...ESPECIALLY OVER THE EASTERN HALF OF LAKE ONTARIO
WHERE THE STORMS COULD BECOME QUITE STRONG. MARINERS THROUGHOUT
THE LOWER GREAT LAKES SHOULD BE ALERT FOR POSSIBLE MARINE WARNINGS
THROUGHOUT THE DAY.

WINDS WILL DROP BELOW SMALL CRAFT ADVISORY LEVELS THIS EVENING
AND REMAIN RELATIVELY LIGHT DURING THE OVERNIGHT HOURS. THESE
WINDS WILL FRESHEN AGAIN ON TUESDAY AS ANOTHER FRONTAL BOUNDARY
WILL PUSH SOUTH ACROSS THE LOWER GREAT LAKES. THIS WILL ENCOURAGE
WAVES TO BUILD TO 3 TO 5 FEET...WITH ANOTHER ROUND OF SMALL CRAFT
ADVISORIES LIKELY FOR THE NEARSHORE WATERS OF LAKE ERIE AND
POSSIBLY FOR THE EASTERN END OF LAKE ONTARIO.

A FALL LIKE AIRMASS IN THE WAKE OF THIS SECOND COLD FRONT COULD
SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND
WEDNESDAY. WILL CARRY SLIGHT CHC FOR SPOUTS IN THE GRIDDED DATA
BASE FOR NOW. STAY TUNED.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ042>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 030827
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
427 AM EDT MON AUG 3 2015

.SYNOPSIS...
A COLD FRONT OVER SOUTHERN ONTARIO WILL SLOWLY PUSH ACROSS OUR
FORECAST AREA TODAY WHILE PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. SOME OF THESE STORMS COULD BECOME STRONG TO
SEVERE... ESPECIALLY EAST OF THE GENESEE VALLEY. A SECONDARY
COLD FRONT WILL TOUCH OFF A COUPLE MORE SHOWERS TUESDAY AND
TUESDAY NIGHT...OTHERWISE IT WILL BECOME COOLER AND MORE
COMFORTABLE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
IT WILL BE AN UNSETTLED DAY ACROSS OUR FORECAST AREA TODAY AS A
WAVY FRONTAL BOUNDARY OVER SOUTHERN ONTARIO WILL SLOWLY MAKE ITS
TO THE EAST...GENERATING SHOWERS AND THUNDERSTORMS IN THE PROCESS.
SOME OF THE CONVECTION WILL BECOME STRONG TO SEVERE DURING THE
MIDDAY AND AFTERNOON...WITH THE GREATEST RISK COMING SOUTH AND
EAST OF THE IAG FRONTIER.

A COUPLE WEAK WAVES HAVE ALREADY RIPPLED TO THE NORTHEAST ALONG
THE FRONTAL BOUNDARY...BUT A STRONGER WAVE IN THE VCNTY OF CHICAGO
AT 08Z IS PREVENTING THE FRONT FROM MAKING A STRONGER PUSH TO THE
EAST. THIS WAVE WILL RIDE ALONG THE FRONT AND CROSS THE LOWER
GREAT LAKES DURING THE MORNING HOURS...THUS ALLOWING THE FRONT TO
SURGE A BIT TO OUR WESTERN DOORSTEP BY MIDDAY...BUT GUIDANCE IS
SUGGESTING THAT ADDITIONAL WAVES WILL KEEP THE AFTERNOON
PROGRESSION TO A CRAWL.

DESPITE A FAIR AMOUNT OF MID AND HIGH LEVEL CLOUD COVER...THE
SLOW FRONTAL PASSAGE WILL ENCOURAGE MOST OF OUR FORECAST AREA TO
FURTHER DESTABILIZE. THIS WILL SET THE STAGE FOR STRONG TO SEVERE
CONVECTION LATER TODAY...PARTICULARLY OVER THE SOUTHERN TIER AND
FOR SITES EAST OF THE GENESEE VALLEY. SBCAPES FOR THESE AREAS ARE
FORECAST TO CLIMB TO AN AVERAGE OF 1500-2000 J/KG...WHILE BULK
SHEAR VALUES WILL RANGE FROM 40 TO AS MUCH AS 50 KNOTS. THIS WILL
CERTAINLY SUPPORT WELL ORGANIZED CONVECTION...WITH A GENERAL
UNIDIRECTIONAL FLOW FAVORING BOWING LINE SEGMENTS WITH DAMAGING
STRAIGHT LINE WINDS. ONE CONCERN IS ONE OF THE AFOREMENTIONED SFC
WAVES COULD PASS OVER THE REGION LATER THIS AFTERNOON AND BACK LOW
LEVEL WINDS ENOUGH TO GENERATE AN ISOLATED SUPERCELL OVER THE SRN
TIER OR FINGER LAKES. THIS RISK WOULD BE QUITE LOW...BUT WORTHY OF
KEEPING IN MIND. WILL USE LIKELY POPS TO THE EAST OF THE IAG
FRONTIER WHERE THE STRONGER...MORE WIDESPREAD CONVECTION IS
EXPECTED...WHILE HIGH CHC POPS WILL BE IN PLACE ELSEWHERE.

OTHERWISE IT WILL BE WARM AND HUMID ACROSS THE REGION
TODAY...WITH THE MOST UNCOMFORTABLE CONDITIONS BEING FOUND OVER
THE FINGER LAKES AND EASTERN LAKE ONTARIO REGION WHERE
TEMPERATURES COULD CLIMB INTO THE MID 80S.

THE INITIAL COLD FRONT WILL LIMP TO OUR EAST TONIGHT...WHILE A
SECONDARY COLD FRONT WILL SETTLE ACROSS SOUTHERN ONTARIO TO OUR
DOORSTEP BY DAYBREAK. IT WILL BE THIS SECOND FRONT THAT WILL
ACTUALLY USHER IN A DIFFERENT AIRMASS...AS COOLER AND LESS HUMID
AIR WILL FOLLOW FOR THE REMAINDER OF THE WEEK. IN TERMS OF
PCPN...ANY LEFTOVER SHOWERS FROM THE FIRST FRONTAL BOUNDARY WILL
QUICKLY END DURING THE EVENING HOURS...BUT SHOWERS FROM THE
APPROACHING SECONDARY FRONT COULD BLOSSOM OVER AN INCREASINGLY
UNSTABLE AIRMASS OVER THE WARM WATERS OF LAKE ONTARIO BY DAYBREAK.
THIS IS A HINT OF THINGS TO COME.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
ON TUESDAY...THE AXIS OF THE MAIN UPPER LEVEL TROUGH WILL SETTLE
FROM THE WESTERN GREAT LAKES INTO SOUTHERN ONTARIO...ALONG WITH A
CORRESPONDING SURFACE TROUGH/SECONDARY COLD FRONT. WITH DIURNAL
HEATING OF THE COOLER AIRMASS THAT WILL BE IN PLACE ALOFT AND ONE
OR MORE SHORTWAVE IMPULSES SLIDING THROUGH THE BASE OF THE UPPER
LEVEL TROUGH AND ACROSS OUR REGION...EXPECT ANOTHER ROUND OF
SCATTERED SHOWERS AND THUNDERSTORMS TO AFFECT OUR REGION THROUGH
THE DAY ON TUESDAY. THE BEST POTENTIAL FOR THESE WILL MOST LIKELY
BE FOUND ACROSS THE NORTH COUNTRY AS THIS REGION SHOULD BE MORE
DIRECTLY IMPACTED BY THE PASSING MID AND UPPER LEVEL IMPULSES...
WITH PRECIP CHANCES LARGELY EXHIBITING A GRADUAL DECREASE WITH
INCREASING SOUTHWESTWARD EXTENT. OTHERWISE...THE CONTINUED GRADUAL
BUT STEADY COOL AIR ADVECTION REGIME WILL LEAD TO 850 MB TEMPS
FALLING TO THE +9C TO +12C RANGE BY AFTERNOON...WHICH SHOULD IN
TURN TRANSLATE INTO DAYTIME HIGHS REACHING THE LOWER TO MID 70S IN
MOST PLACES.

DURING TUESDAY NIGHT THE SECONDARY COLD FRONT WILL TRAVERSE OUR
REGION IN CONJUNCTION WITH THE MAIN UPPER LEVEL TROUGH AXIS. WHILE
LINGERING DIURNALLY-DRIVEN SHOWERS AND STORMS AT THE START OF THE
EVENING WILL PROBABLY BE FOLLOWED BY SOME ADDITIONAL SCATTERED
SHOWER ACTIVITY AS THESE FEATURES PASS...IN GENERAL THE LOSS OF
DAYTIME HEATING AND THE ARRIVAL OF DRIER AIR BEHIND THE SECONDARY
FRONT SHOULD LEAD TO PRECIP CHANCES DIMINISHING OVER TIME. THE ONE
EXCEPTION TO THIS WILL BE EAST OF LAKE ONTARIO... WHERE A WESTERLY
FLOW OF PROGRESSIVELY COOLER AIR CROSSING THE WARMER LAKE WATERS
WILL CONTINUE TO GENERATE SCATTERED SHOWERS RIGHT THROUGH THE
NIGHT VIA A COMBINATION OF OROGRAPHIC AND LAKE EFFECT
PROCESSES...AS 850 MB TEMPS WILL FALL TO BETWEEN +7C AND +8C. AS
FOR TEMPERATURES...EXPECT COMFORTABLE CONDITIONS FOR SLEEPING WITH
OVERNIGHT LOWS RANGING FROM THE LOWER TO MID 50S ACROSS INTERIOR
PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO RIGHT AROUND 60
ALONG THE IMMEDIATE LAKESHORES.

ON WEDNESDAY...THE CORE OF THE UPPER LEVEL TROUGH WILL MEANDER
ITS WAY EAST ACROSS QUEBEC PROVINCE...WHILE SURFACE-BASED RIDGING
AND DRIER AIR DRAPED FROM THE WESTERN GREAT LAKES TO THE OHIO
VALLEY BUILDS EASTWARD INTO THE CENTRAL GREAT LAKES. WHILE THE
LATTER SHOULD RESULT IN A MAINLY DRY DAY FOR MOST AREAS SOUTH OF
LAKE ONTARIO...THE FAR NORTHEASTERN FINGER LAKES REGION AND NORTH
CENTRAL NEW YORK WILL BE SUBJECT TO SOME ADDITIONAL SCATTERED LAKE
AND OROGRAPHICALLY-DRIVEN SHOWERS EARLY WEDNESDAY...FOLLOWED BY
MORE GENERAL DIURNALLY-DRIVEN SHOWERS THE BALANCE OF THE DAY AS
ANOTHER SHORTWAVE SWINGS THROUGH THE BASE OF THE UPPER TROUGH IN
CONJUNCTION WITH RENEWED DAYTIME HEATING. ALL OF THIS SHOULD THEN
QUICKLY WIND DOWN WEDNESDAY NIGHT WITH THE LOSS OF HEATING AND AS
THE AFOREMENTIONED RIDGE BUILDS DIRECTLY OVERHEAD... RESULTING IN
A RETURN TO DRY WEATHER AREAWIDE TO CLOSE OUT THE SHORT TERM
PERIOD.

WITH RESPECT TO TEMPERATURES WEDNESDAY AND WEDNESDAY NIGHT...THESE
SHOULD REMAIN SOLIDLY BELOW NORMAL...AND SHOULD IN FACT BOTTOM OUT
FOR THE WEEK AS OUR AIRMASS REACHES ITS COOLEST OVERALL POINT OF
THE NEXT SEVEN DAYS. 850 MB TEMPS OF ROUGHLY +7C TO +10C SHOULD
TRANSLATE INTO HIGHS MOSTLY IN THE UPPER 60S TO LOWER 70S ON
WEDNESDAY...WITH THE COOLEST READINGS ACROSS THE HIGHER
TERRAIN...AND THE WARMEST OVERALL TEMPS FOUND IN THE GENESEE
VALLEY/WESTERN FINGER LAKES... WHERE A FEW SPOTS COULD STILL REACH
THE MID 70S. SUCH READINGS WILL THEN BE FOLLOWED BY LOWS RANGING
THROUGH THE 50S WEDNESDAY NIGHT... WHEN THE COOLEST INTERIOR
PORTIONS OF THE SOUTHERN TIER AND NORTH COUNTRY COULD TICKLE THE
50 DEGREE MARK.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
IN THE LONGER TERM PORTION OF THE FORECAST...THE MID AND UPPER
LEVEL FLOW ACROSS OUR REGION WILL TEND TO GRADUALLY DEAMPLIFY
THROUGH THE LATTER PORTIONS OF THE WORK WEEK AND INTO THE FIRST
PART OF THE UPCOMING WEEKEND AS THE CORE OF THIS WEEK/S MAIN UPPER
TROUGH LIFTS OUT INTO THE NORTHERN ATLANTIC...AND MAY EVEN BRIEFLY
GO QUASI-ZONAL BEFORE A VERY MODEST MID-LEVEL TROUGH APPROACHES
OUR REGION IN TIME FOR SUNDAY. AS A RESULT...INITIALLY BELOW
NORMAL TEMPERATURES LATE IN THE WORK WEEK SHOULD TREND CLOSER TO
SEASONAL AVERAGES BY NEXT WEEKEND. MORE SPECIFICALLY...DAYTIME
HIGHS INITIALLY IN THE LOWER TO MID 70S ON THURSDAY SHOULD CLIMB
BACK INTO THE MID AND UPPER 70S FOR NEXT WEEKEND...WHILE NIGHTTIME
LOWS INITIALLY RANGING THROUGH THE 50S SHOULD SLOWLY MODERATE INTO
THE 55-60 RANGE.

AS FOR PRECIPITATION CHANCES...MAINLY DRY WEATHER SHOULD PREVAIL
THURSDAY THROUGH SATURDAY AS EXPANSIVE CANADIAN HIGH PRESSURE
DRAPED FROM ONTARIO PROVINCE TO THE UPPER OHIO VALLEY AT THE START
OF THE PERIOD SLOWLY DRIFTS EASTWARD INTO QUEBEC...AND KEEPS THE
MAIN SURFACE FRONTAL ZONE/ANY ATTENDANT WAVES OF LOW PRESSURE
SUPPRESSED TO OUR SOUTH. AFTER THAT...THE AFOREMENTIONED MID-LEVEL
TROUGH SHOULD PROVIDE ENOUGH OF AN INCREASE IN MOISTURE AND
SYNOPTIC- SCALE LIFT TO RESULT IN LIMITED CHANCES FOR
SHOWERS/THUNDERSTORMS RETURNING ON SUNDAY...WHICH AT THIS DISTANT
VANTAGE POINT WILL BE COVERED WITH SOME VERY LOW CHANCE POPS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY AFFECTING THE
KJHW... KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 08Z WILL REMAIN IN PLACE
THROUGH AT LEAST MIDDAY. FOR THIS AFTERNOON...WHILE VFR CIGS ARE
ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS WILL BE
FOUND IN AND NEAR CONVECTION.

TONIGHT...VFR CONDITIONS WILL BE FOUND ACROSS THE MAJORITY OF THE
REGION. THE EXCEPTION COULD BE ACROSS THE SOUTHERN TIER WHERE MVFR
CIGS COULD DEVELOP AFTER MIDNIGHT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES
AT KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO
POSSIBLE AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
A RELATIVELY TIGHT SFC PRESSURE GRADIENT WILL COMBINE WITH A
STRONG LOW LEVEL JET AHEAD OF A COLD FRONT TO PRODUCE GUSTY WINDS
ACROSS THE LOWER GREAT LAKES TODAY. A SMALL CRAFT ADVISORY IS
ALREADY IN PLACE FOR ALL OF THE NEW YORK NEARSHORE WATERS...AS
WELL AS BUF HARBOR...FOR WINDS THAT COULD GUST TO 30 KNOTS. THIS
WILL ESPECIALLY BE THE CASE ON LAKE ERIE. THE WINDS WILL DROP OFF
LATER THIS AFTERNOON AND EVENING IN THE WAKE OF A SLOW MOVING COLD
FRONT.

THE COLD FRONT WILL LIKELY GENERATE SOME SHOWERS AND
THUNDERSTORMS...ESPECIALLY OVER THE EASTERN HALF OF LAKE ONTARIO
WHERE THE STORMS COULD BECOME QUITE STRONG. MARINERS THROUGHOUT
THE LOWER GREAT LAKES SHOULD BE ALERT FOR POSSIBLE MARINE WARNINGS
THROUGHOUT THE DAY.

WINDS WILL DROP BELOW SMALL CRAFT ADVISORY LEVELS THIS EVENING
AND REMAIN RELATIVELY LIGHT DURING THE OVERNIGHT HOURS. THESE
WINDS WILL FRESHEN AGAIN ON TUESDAY AS ANOTHER FRONTAL BOUNDARY
WILL PUSH SOUTH ACROSS THE LOWER GREAT LAKES. THIS WILL ENCOURAGE
WAVES TO BUILD TO 3 TO 5 FEET...WITH ANOTHER ROUND OF SMALL CRAFT
ADVISORIES LIKELY FOR THE NEARSHORE WATERS OF LAKE ERIE AND
POSSIBLY FOR THE EASTERN END OF LAKE ONTARIO.

A FALL LIKE AIRMASS IN THE WAKE OF THIS SECOND COLD FRONT COULD
SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND
WEDNESDAY. WILL CARRY SLIGHT CHC FOR SPOUTS IN THE GRIDDED DATA
BASE FOR NOW. STAY TUNED.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ042>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH




000
FXUS61 KBUF 030607
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
207 AM EDT MON AUG 3 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
A LINEAR MCS THAT WAS FOUND OVER MICHIGAN AND SOUTHERN ONTARIO AT
MIDNIGHT HAS SINCE PUSHED SOUTH ACROSS LAKE ERIE...WHILE WEAKER
CONVECTION HAS MADE ITS WAY OVER LAKE ONTARIO TO THE THOUSAND
ISLANDS REGION. THE LATTER CONVECTION WILL CONTINUE TO WEAKEN DURING
THE REMAINING PRE DAWN HOURS WHILE 40 TO 50KT WINDS BASED
AROUND 4K FT WILL PUSH THE BULK OF THE TRAILING STRATIFORM RAIN OVER
SOUTHERN ONTARIO TO THE NORTH. SIMPLIFYING THIS...THE VAST MAJORITY
OF OUR FORECAST AREA WILL REMAIN DRY FOR THE OVERNIGHT WITH ONLY THE
FAR WESTERN COUNTIES AND THE THOUSAND ISLANDS REGION HAVING THE RISK
FOR ANY THUNDERSTORM ACTIVITY. TEMPERATURES WILL REMAIN ELEVATED...
WITH READINGS HOLDING NEARLY STEADY IN THE 70S ACROSS THE LAKE
PLAINS WHILE TEMPS WILL BE IN THE MID TO UPPER 60S IN THE SRN TIER.

AS WE PUSH PAST DAYBREAK...THE WEAKENED CONVECTION OVER SOUTHERN
ONTARIO WILL PUSH EAST AND START TO ADVANCE ACROSS OUR FORECAST
AREA. THE COLD FRONT RESPONSIBLE FOR FORCING THIS CONVECTION HAS
BEEN SLOW TO MOVE EAST BECAUSE OF EMBEDDED WAVES...BUT NOW THAT THE
LAST OF THESE WAVES HAS PASSED...THE FRONT SHOULD PICK UP SPEED
DURING THE COURSE OF THE DAY.

THE CONVECTION WILL BE SPOTTY AND WEAK FOR THE FIRST PART OF
TODAY...THEN AS DAYTIME INSTABILITY MOUNTS...THE ACTIVITY SHOULD
STRENGTHEN EAST OF THE GENESEE VALLEY. IN FACT...THE STORM
PREDICTION CENTER HAS OUTLINED MOST OF WESTERN NEW YORK WITHIN A
SLIGHT RISK FOR SEVERE STORMS...AGAIN...WITH THE GREATEST CHANCE
COMING EAST OF THE GENESEE VALLEY WHERE SBCAPES OF 1000-2000 J/KG
COULD BE REALIZED. GIVEN THE UNIDIRECTIONAL...SPEED SHEARED
ENVIRONMENT...THE GREATEST SEVERE WEATHER THREAT WILL COME FROM
DAMAGING STRAIGHT LINE WINDS.

TEMPERATURES LATER TODAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY EFFECTING THE KJHW...
KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 06Z ARE EXPECTED TO REMAIN IN
PLACE THROUGH AT LEAST MIDDAY. FOR THE AFTERNOON...WHILE VFR CIGS
ARE ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS IN AND NEAR
CONVECTION CAN BE EXPECTED.

VFR CONDITIONS ARE EXPECTED MONDAY NIGHT IN THE WAKE OF AN EXITING
COLD FRONT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES AT
KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO POSSIBLE
AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 35 KNOTS OVERNIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...WCH
NEAR TERM...RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...RSH/SMITH/WCH




000
FXUS61 KBUF 030607
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
207 AM EDT MON AUG 3 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
A LINEAR MCS THAT WAS FOUND OVER MICHIGAN AND SOUTHERN ONTARIO AT
MIDNIGHT HAS SINCE PUSHED SOUTH ACROSS LAKE ERIE...WHILE WEAKER
CONVECTION HAS MADE ITS WAY OVER LAKE ONTARIO TO THE THOUSAND
ISLANDS REGION. THE LATTER CONVECTION WILL CONTINUE TO WEAKEN DURING
THE REMAINING PRE DAWN HOURS WHILE 40 TO 50KT WINDS BASED
AROUND 4K FT WILL PUSH THE BULK OF THE TRAILING STRATIFORM RAIN OVER
SOUTHERN ONTARIO TO THE NORTH. SIMPLIFYING THIS...THE VAST MAJORITY
OF OUR FORECAST AREA WILL REMAIN DRY FOR THE OVERNIGHT WITH ONLY THE
FAR WESTERN COUNTIES AND THE THOUSAND ISLANDS REGION HAVING THE RISK
FOR ANY THUNDERSTORM ACTIVITY. TEMPERATURES WILL REMAIN ELEVATED...
WITH READINGS HOLDING NEARLY STEADY IN THE 70S ACROSS THE LAKE
PLAINS WHILE TEMPS WILL BE IN THE MID TO UPPER 60S IN THE SRN TIER.

AS WE PUSH PAST DAYBREAK...THE WEAKENED CONVECTION OVER SOUTHERN
ONTARIO WILL PUSH EAST AND START TO ADVANCE ACROSS OUR FORECAST
AREA. THE COLD FRONT RESPONSIBLE FOR FORCING THIS CONVECTION HAS
BEEN SLOW TO MOVE EAST BECAUSE OF EMBEDDED WAVES...BUT NOW THAT THE
LAST OF THESE WAVES HAS PASSED...THE FRONT SHOULD PICK UP SPEED
DURING THE COURSE OF THE DAY.

THE CONVECTION WILL BE SPOTTY AND WEAK FOR THE FIRST PART OF
TODAY...THEN AS DAYTIME INSTABILITY MOUNTS...THE ACTIVITY SHOULD
STRENGTHEN EAST OF THE GENESEE VALLEY. IN FACT...THE STORM
PREDICTION CENTER HAS OUTLINED MOST OF WESTERN NEW YORK WITHIN A
SLIGHT RISK FOR SEVERE STORMS...AGAIN...WITH THE GREATEST CHANCE
COMING EAST OF THE GENESEE VALLEY WHERE SBCAPES OF 1000-2000 J/KG
COULD BE REALIZED. GIVEN THE UNIDIRECTIONAL...SPEED SHEARED
ENVIRONMENT...THE GREATEST SEVERE WEATHER THREAT WILL COME FROM
DAMAGING STRAIGHT LINE WINDS.

TEMPERATURES LATER TODAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY EFFECTING THE KJHW...
KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 06Z ARE EXPECTED TO REMAIN IN
PLACE THROUGH AT LEAST MIDDAY. FOR THE AFTERNOON...WHILE VFR CIGS
ARE ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS IN AND NEAR
CONVECTION CAN BE EXPECTED.

VFR CONDITIONS ARE EXPECTED MONDAY NIGHT IN THE WAKE OF AN EXITING
COLD FRONT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES AT
KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO POSSIBLE
AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 35 KNOTS OVERNIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...WCH
NEAR TERM...RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...RSH/SMITH/WCH





000
FXUS61 KBUF 030607
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
207 AM EDT MON AUG 3 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
A LINEAR MCS THAT WAS FOUND OVER MICHIGAN AND SOUTHERN ONTARIO AT
MIDNIGHT HAS SINCE PUSHED SOUTH ACROSS LAKE ERIE...WHILE WEAKER
CONVECTION HAS MADE ITS WAY OVER LAKE ONTARIO TO THE THOUSAND
ISLANDS REGION. THE LATTER CONVECTION WILL CONTINUE TO WEAKEN DURING
THE REMAINING PRE DAWN HOURS WHILE 40 TO 50KT WINDS BASED
AROUND 4K FT WILL PUSH THE BULK OF THE TRAILING STRATIFORM RAIN OVER
SOUTHERN ONTARIO TO THE NORTH. SIMPLIFYING THIS...THE VAST MAJORITY
OF OUR FORECAST AREA WILL REMAIN DRY FOR THE OVERNIGHT WITH ONLY THE
FAR WESTERN COUNTIES AND THE THOUSAND ISLANDS REGION HAVING THE RISK
FOR ANY THUNDERSTORM ACTIVITY. TEMPERATURES WILL REMAIN ELEVATED...
WITH READINGS HOLDING NEARLY STEADY IN THE 70S ACROSS THE LAKE
PLAINS WHILE TEMPS WILL BE IN THE MID TO UPPER 60S IN THE SRN TIER.

AS WE PUSH PAST DAYBREAK...THE WEAKENED CONVECTION OVER SOUTHERN
ONTARIO WILL PUSH EAST AND START TO ADVANCE ACROSS OUR FORECAST
AREA. THE COLD FRONT RESPONSIBLE FOR FORCING THIS CONVECTION HAS
BEEN SLOW TO MOVE EAST BECAUSE OF EMBEDDED WAVES...BUT NOW THAT THE
LAST OF THESE WAVES HAS PASSED...THE FRONT SHOULD PICK UP SPEED
DURING THE COURSE OF THE DAY.

THE CONVECTION WILL BE SPOTTY AND WEAK FOR THE FIRST PART OF
TODAY...THEN AS DAYTIME INSTABILITY MOUNTS...THE ACTIVITY SHOULD
STRENGTHEN EAST OF THE GENESEE VALLEY. IN FACT...THE STORM
PREDICTION CENTER HAS OUTLINED MOST OF WESTERN NEW YORK WITHIN A
SLIGHT RISK FOR SEVERE STORMS...AGAIN...WITH THE GREATEST CHANCE
COMING EAST OF THE GENESEE VALLEY WHERE SBCAPES OF 1000-2000 J/KG
COULD BE REALIZED. GIVEN THE UNIDIRECTIONAL...SPEED SHEARED
ENVIRONMENT...THE GREATEST SEVERE WEATHER THREAT WILL COME FROM
DAMAGING STRAIGHT LINE WINDS.

TEMPERATURES LATER TODAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY EFFECTING THE KJHW...
KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 06Z ARE EXPECTED TO REMAIN IN
PLACE THROUGH AT LEAST MIDDAY. FOR THE AFTERNOON...WHILE VFR CIGS
ARE ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS IN AND NEAR
CONVECTION CAN BE EXPECTED.

VFR CONDITIONS ARE EXPECTED MONDAY NIGHT IN THE WAKE OF AN EXITING
COLD FRONT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES AT
KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO POSSIBLE
AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 35 KNOTS OVERNIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...WCH
NEAR TERM...RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...RSH/SMITH/WCH





000
FXUS61 KBUF 030607
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
207 AM EDT MON AUG 3 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
A LINEAR MCS THAT WAS FOUND OVER MICHIGAN AND SOUTHERN ONTARIO AT
MIDNIGHT HAS SINCE PUSHED SOUTH ACROSS LAKE ERIE...WHILE WEAKER
CONVECTION HAS MADE ITS WAY OVER LAKE ONTARIO TO THE THOUSAND
ISLANDS REGION. THE LATTER CONVECTION WILL CONTINUE TO WEAKEN DURING
THE REMAINING PRE DAWN HOURS WHILE 40 TO 50KT WINDS BASED
AROUND 4K FT WILL PUSH THE BULK OF THE TRAILING STRATIFORM RAIN OVER
SOUTHERN ONTARIO TO THE NORTH. SIMPLIFYING THIS...THE VAST MAJORITY
OF OUR FORECAST AREA WILL REMAIN DRY FOR THE OVERNIGHT WITH ONLY THE
FAR WESTERN COUNTIES AND THE THOUSAND ISLANDS REGION HAVING THE RISK
FOR ANY THUNDERSTORM ACTIVITY. TEMPERATURES WILL REMAIN ELEVATED...
WITH READINGS HOLDING NEARLY STEADY IN THE 70S ACROSS THE LAKE
PLAINS WHILE TEMPS WILL BE IN THE MID TO UPPER 60S IN THE SRN TIER.

AS WE PUSH PAST DAYBREAK...THE WEAKENED CONVECTION OVER SOUTHERN
ONTARIO WILL PUSH EAST AND START TO ADVANCE ACROSS OUR FORECAST
AREA. THE COLD FRONT RESPONSIBLE FOR FORCING THIS CONVECTION HAS
BEEN SLOW TO MOVE EAST BECAUSE OF EMBEDDED WAVES...BUT NOW THAT THE
LAST OF THESE WAVES HAS PASSED...THE FRONT SHOULD PICK UP SPEED
DURING THE COURSE OF THE DAY.

THE CONVECTION WILL BE SPOTTY AND WEAK FOR THE FIRST PART OF
TODAY...THEN AS DAYTIME INSTABILITY MOUNTS...THE ACTIVITY SHOULD
STRENGTHEN EAST OF THE GENESEE VALLEY. IN FACT...THE STORM
PREDICTION CENTER HAS OUTLINED MOST OF WESTERN NEW YORK WITHIN A
SLIGHT RISK FOR SEVERE STORMS...AGAIN...WITH THE GREATEST CHANCE
COMING EAST OF THE GENESEE VALLEY WHERE SBCAPES OF 1000-2000 J/KG
COULD BE REALIZED. GIVEN THE UNIDIRECTIONAL...SPEED SHEARED
ENVIRONMENT...THE GREATEST SEVERE WEATHER THREAT WILL COME FROM
DAMAGING STRAIGHT LINE WINDS.

TEMPERATURES LATER TODAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
STRONG THUNDERSTORMS HAVE PUSHED SOUTH ACROSS LAKE ERIE...BUT
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORM ACTIVITY WILL BE
POSSIBLE LATER TODAY. THIS WILL ESPECIALLY BE THE CASE FOR SITES
SOUTH AND EAST OF THE IAG FRONTIER...POSSIBLY EFFECTING THE KJHW...
KROC AND KART TAF SITES.

OTHERWISE...VFR CONDITIONS IN PLACE AT 06Z ARE EXPECTED TO REMAIN IN
PLACE THROUGH AT LEAST MIDDAY. FOR THE AFTERNOON...WHILE VFR CIGS
ARE ANTICIPATED...THERE MAY BE TIMES WHEN MVFR CONDITIONS IN AND NEAR
CONVECTION CAN BE EXPECTED.

VFR CONDITIONS ARE EXPECTED MONDAY NIGHT IN THE WAKE OF AN EXITING
COLD FRONT.

WINDS THROUGH EARLY THIS AFTERNOON WILL GUST TO 30 KNOTS AT TIMES AT
KBUF...KIAG AND KROC...WITH SOME LOW LEVEL WIND SHEAR ALSO POSSIBLE
AT KROC BEFORE DAYBREAK.

OUTLOOK...

TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 35 KNOTS OVERNIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...WCH
NEAR TERM...RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...RSH/SMITH/WCH




000
FXUS61 KBUF 030311
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1111 PM EDT SUN AUG 2 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
RADAR AT 11PM SHOWS A LINE OF STRONG THUNDERSTORMS APPROACHING THE
NIAGARA FRONTIER. THIS IS OCCURRING FASTER THAN PREVIOUS GUIDANCE
SHOWED SO THE FORECAST HAS BEEN UPDATED LATE THIS EVENING TO REFLECT
THIS. 00Z KBUF SOUNDING SHOWS A MODERATELY UNSTABLE ENVIRONMENT HAS
WORKED OVER THE FORECAST AREA WITH RECENT VAD WIND PROFILES SHOWING
A 40-50 KNOT LOW LEVEL JET ALSO IN PLACE BOTHER SUPPORTING THE LINE
OF STORMS.

A COLD FRONT STRETCHED ACROSS MICHIGAN WITH A STRONG SHORTWAVE
TROUGH ALOFT ARE SUPPORTING THE CONVECTIVE ACTIVITY. MESO GUIDANCE
SLOWS/WEAKENS THIS ACTIVITY OVERNIGHT AS IT DRIFTS OVER WESTERN NEW
YORK SO HAVE TRENDED POPS DOWN TO CHANCE LATE OVERNIGHT.

THE COMBINATION OF A PRESSURE GRADIENT OVER THE EASTERN GREAT LAKES
AND A 50-60KT LOW LEVEL JET WILL BRING GUSTS TO THE 20-30 MPH RANGE
OVERNIGHT OUTSIDE OF ANY CONVECTIVE GUSTS FROM THE STORMS.
TEMPERATURES IN MOST AREAS WILL ONLY FALL INTO THE THE UPPER 60S OR
LOWER 70S.

THE COLD FRONT WILL CROSS WESTERN NEW YORK MONDAY MORNING THEN
SHIFTING TOWARD CENTRAL NEW YORK BY THE AFTERNOON HOURS. DEWPOINT
POOLING AHEAD OF THE FRONT WILL BOOST SURFACE DEWPOINTS INTO THE
MIDDLE TO UPPER 60S. A CAPED ENVIRONMENT PER FORECAST SOUNDING SHOULD
KEEP ANY ACTIVITY TAME IN THE MORNING. LOW LEVEL CONVERGENCE ALONG
THE FRONT WILL PROVIDE LIFT WITH INCREASING INSTABILITY GOING INTO
THE AFTERNOON WITH DIURNAL HEATING. FORECASTED CAPE WILL INCREASE TO
1000-2000 J/KG WITHIN A UNIDIRECTIONALLY SHEARED ENVIRONMENT UP TO
50KTS SUPPORTING THE POTENTIAL FOR SEVERE LINER STORMS WITH POSSIBLE
BOWING SEGMENTS PRODUCING DAMAGING WINDS. THE TIMING OF THE FRONT
WILL PLAY A BIG PART IN EXACTLY WHERE STRONG STORMS WILL SET UP WITH
A BETTER POTENTIAL FROM THE FINGER LAKES EASTWARD. TEMPERATURES
DURING MONDAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S PRIOR TO THE
FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
LINE OF TSRA APPROACHING THE NIAGARA FRONTIER LATE THIS EVENING. HAVE
AMENDED TAFS TO REFLECT MUCH EARLIER ARRIVAL OF STORMS. VFR EXPECTED
OUTSIDE OF TSRA WITH SOME GUSTY WINDS DEVELOPING. MVFR/IFR POSSIBLE
WITHIN TSRA. A 50KT LOW LEVEL JET PER VAD WIND PROFILES IS ALSO IN
PLACE BRINGING LOW LEVEL WIND SHEAR TO THE TAF SITES.

ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE COLD
FRONTAL PASSAGE ON MONDAY. THERE MAY BE LOWER MVFR TO IFR CONDITIONS
WITH THE STORMS...AS WELL AS THE RISK OF SEVERE CATEGORY WIND
GUSTS...BUT MOST OF THE TIME WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH





000
FXUS61 KBUF 030311
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1111 PM EDT SUN AUG 2 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
RADAR AT 11PM SHOWS A LINE OF STRONG THUNDERSTORMS APPROACHING THE
NIAGARA FRONTIER. THIS IS OCCURRING FASTER THAN PREVIOUS GUIDANCE
SHOWED SO THE FORECAST HAS BEEN UPDATED LATE THIS EVENING TO REFLECT
THIS. 00Z KBUF SOUNDING SHOWS A MODERATELY UNSTABLE ENVIRONMENT HAS
WORKED OVER THE FORECAST AREA WITH RECENT VAD WIND PROFILES SHOWING
A 40-50 KNOT LOW LEVEL JET ALSO IN PLACE BOTHER SUPPORTING THE LINE
OF STORMS.

A COLD FRONT STRETCHED ACROSS MICHIGAN WITH A STRONG SHORTWAVE
TROUGH ALOFT ARE SUPPORTING THE CONVECTIVE ACTIVITY. MESO GUIDANCE
SLOWS/WEAKENS THIS ACTIVITY OVERNIGHT AS IT DRIFTS OVER WESTERN NEW
YORK SO HAVE TRENDED POPS DOWN TO CHANCE LATE OVERNIGHT.

THE COMBINATION OF A PRESSURE GRADIENT OVER THE EASTERN GREAT LAKES
AND A 50-60KT LOW LEVEL JET WILL BRING GUSTS TO THE 20-30 MPH RANGE
OVERNIGHT OUTSIDE OF ANY CONVECTIVE GUSTS FROM THE STORMS.
TEMPERATURES IN MOST AREAS WILL ONLY FALL INTO THE THE UPPER 60S OR
LOWER 70S.

THE COLD FRONT WILL CROSS WESTERN NEW YORK MONDAY MORNING THEN
SHIFTING TOWARD CENTRAL NEW YORK BY THE AFTERNOON HOURS. DEWPOINT
POOLING AHEAD OF THE FRONT WILL BOOST SURFACE DEWPOINTS INTO THE
MIDDLE TO UPPER 60S. A CAPED ENVIRONMENT PER FORECAST SOUNDING SHOULD
KEEP ANY ACTIVITY TAME IN THE MORNING. LOW LEVEL CONVERGENCE ALONG
THE FRONT WILL PROVIDE LIFT WITH INCREASING INSTABILITY GOING INTO
THE AFTERNOON WITH DIURNAL HEATING. FORECASTED CAPE WILL INCREASE TO
1000-2000 J/KG WITHIN A UNIDIRECTIONALLY SHEARED ENVIRONMENT UP TO
50KTS SUPPORTING THE POTENTIAL FOR SEVERE LINER STORMS WITH POSSIBLE
BOWING SEGMENTS PRODUCING DAMAGING WINDS. THE TIMING OF THE FRONT
WILL PLAY A BIG PART IN EXACTLY WHERE STRONG STORMS WILL SET UP WITH
A BETTER POTENTIAL FROM THE FINGER LAKES EASTWARD. TEMPERATURES
DURING MONDAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S PRIOR TO THE
FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
LINE OF TSRA APPROACHING THE NIAGARA FRONTIER LATE THIS EVENING. HAVE
AMENDED TAFS TO REFLECT MUCH EARLIER ARRIVAL OF STORMS. VFR EXPECTED
OUTSIDE OF TSRA WITH SOME GUSTY WINDS DEVELOPING. MVFR/IFR POSSIBLE
WITHIN TSRA. A 50KT LOW LEVEL JET PER VAD WIND PROFILES IS ALSO IN
PLACE BRINGING LOW LEVEL WIND SHEAR TO THE TAF SITES.

ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE COLD
FRONTAL PASSAGE ON MONDAY. THERE MAY BE LOWER MVFR TO IFR CONDITIONS
WITH THE STORMS...AS WELL AS THE RISK OF SEVERE CATEGORY WIND
GUSTS...BUT MOST OF THE TIME WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH




000
FXUS61 KBUF 030311
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1111 PM EDT SUN AUG 2 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
RADAR AT 11PM SHOWS A LINE OF STRONG THUNDERSTORMS APPROACHING THE
NIAGARA FRONTIER. THIS IS OCCURRING FASTER THAN PREVIOUS GUIDANCE
SHOWED SO THE FORECAST HAS BEEN UPDATED LATE THIS EVENING TO REFLECT
THIS. 00Z KBUF SOUNDING SHOWS A MODERATELY UNSTABLE ENVIRONMENT HAS
WORKED OVER THE FORECAST AREA WITH RECENT VAD WIND PROFILES SHOWING
A 40-50 KNOT LOW LEVEL JET ALSO IN PLACE BOTHER SUPPORTING THE LINE
OF STORMS.

A COLD FRONT STRETCHED ACROSS MICHIGAN WITH A STRONG SHORTWAVE
TROUGH ALOFT ARE SUPPORTING THE CONVECTIVE ACTIVITY. MESO GUIDANCE
SLOWS/WEAKENS THIS ACTIVITY OVERNIGHT AS IT DRIFTS OVER WESTERN NEW
YORK SO HAVE TRENDED POPS DOWN TO CHANCE LATE OVERNIGHT.

THE COMBINATION OF A PRESSURE GRADIENT OVER THE EASTERN GREAT LAKES
AND A 50-60KT LOW LEVEL JET WILL BRING GUSTS TO THE 20-30 MPH RANGE
OVERNIGHT OUTSIDE OF ANY CONVECTIVE GUSTS FROM THE STORMS.
TEMPERATURES IN MOST AREAS WILL ONLY FALL INTO THE THE UPPER 60S OR
LOWER 70S.

THE COLD FRONT WILL CROSS WESTERN NEW YORK MONDAY MORNING THEN
SHIFTING TOWARD CENTRAL NEW YORK BY THE AFTERNOON HOURS. DEWPOINT
POOLING AHEAD OF THE FRONT WILL BOOST SURFACE DEWPOINTS INTO THE
MIDDLE TO UPPER 60S. A CAPED ENVIRONMENT PER FORECAST SOUNDING SHOULD
KEEP ANY ACTIVITY TAME IN THE MORNING. LOW LEVEL CONVERGENCE ALONG
THE FRONT WILL PROVIDE LIFT WITH INCREASING INSTABILITY GOING INTO
THE AFTERNOON WITH DIURNAL HEATING. FORECASTED CAPE WILL INCREASE TO
1000-2000 J/KG WITHIN A UNIDIRECTIONALLY SHEARED ENVIRONMENT UP TO
50KTS SUPPORTING THE POTENTIAL FOR SEVERE LINER STORMS WITH POSSIBLE
BOWING SEGMENTS PRODUCING DAMAGING WINDS. THE TIMING OF THE FRONT
WILL PLAY A BIG PART IN EXACTLY WHERE STRONG STORMS WILL SET UP WITH
A BETTER POTENTIAL FROM THE FINGER LAKES EASTWARD. TEMPERATURES
DURING MONDAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S PRIOR TO THE
FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
LINE OF TSRA APPROACHING THE NIAGARA FRONTIER LATE THIS EVENING. HAVE
AMENDED TAFS TO REFLECT MUCH EARLIER ARRIVAL OF STORMS. VFR EXPECTED
OUTSIDE OF TSRA WITH SOME GUSTY WINDS DEVELOPING. MVFR/IFR POSSIBLE
WITHIN TSRA. A 50KT LOW LEVEL JET PER VAD WIND PROFILES IS ALSO IN
PLACE BRINGING LOW LEVEL WIND SHEAR TO THE TAF SITES.

ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE COLD
FRONTAL PASSAGE ON MONDAY. THERE MAY BE LOWER MVFR TO IFR CONDITIONS
WITH THE STORMS...AS WELL AS THE RISK OF SEVERE CATEGORY WIND
GUSTS...BUT MOST OF THE TIME WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH





000
FXUS61 KBUF 030311
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1111 PM EDT SUN AUG 2 2015

.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL WORK ACROSS THE FORECAST AREA AHEAD
OF A COLD FRONT OVERNIGHT. THE COLD FRONT WILL THEN SHIFT ACROSS NEW
YORK ON MONDAY WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE THROUGH MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL
THEN FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE SETTLE IN PLACE FOR
THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
RADAR AT 11PM SHOWS A LINE OF STRONG THUNDERSTORMS APPROACHING THE
NIAGARA FRONTIER. THIS IS OCCURRING FASTER THAN PREVIOUS GUIDANCE
SHOWED SO THE FORECAST HAS BEEN UPDATED LATE THIS EVENING TO REFLECT
THIS. 00Z KBUF SOUNDING SHOWS A MODERATELY UNSTABLE ENVIRONMENT HAS
WORKED OVER THE FORECAST AREA WITH RECENT VAD WIND PROFILES SHOWING
A 40-50 KNOT LOW LEVEL JET ALSO IN PLACE BOTHER SUPPORTING THE LINE
OF STORMS.

A COLD FRONT STRETCHED ACROSS MICHIGAN WITH A STRONG SHORTWAVE
TROUGH ALOFT ARE SUPPORTING THE CONVECTIVE ACTIVITY. MESO GUIDANCE
SLOWS/WEAKENS THIS ACTIVITY OVERNIGHT AS IT DRIFTS OVER WESTERN NEW
YORK SO HAVE TRENDED POPS DOWN TO CHANCE LATE OVERNIGHT.

THE COMBINATION OF A PRESSURE GRADIENT OVER THE EASTERN GREAT LAKES
AND A 50-60KT LOW LEVEL JET WILL BRING GUSTS TO THE 20-30 MPH RANGE
OVERNIGHT OUTSIDE OF ANY CONVECTIVE GUSTS FROM THE STORMS.
TEMPERATURES IN MOST AREAS WILL ONLY FALL INTO THE THE UPPER 60S OR
LOWER 70S.

THE COLD FRONT WILL CROSS WESTERN NEW YORK MONDAY MORNING THEN
SHIFTING TOWARD CENTRAL NEW YORK BY THE AFTERNOON HOURS. DEWPOINT
POOLING AHEAD OF THE FRONT WILL BOOST SURFACE DEWPOINTS INTO THE
MIDDLE TO UPPER 60S. A CAPED ENVIRONMENT PER FORECAST SOUNDING SHOULD
KEEP ANY ACTIVITY TAME IN THE MORNING. LOW LEVEL CONVERGENCE ALONG
THE FRONT WILL PROVIDE LIFT WITH INCREASING INSTABILITY GOING INTO
THE AFTERNOON WITH DIURNAL HEATING. FORECASTED CAPE WILL INCREASE TO
1000-2000 J/KG WITHIN A UNIDIRECTIONALLY SHEARED ENVIRONMENT UP TO
50KTS SUPPORTING THE POTENTIAL FOR SEVERE LINER STORMS WITH POSSIBLE
BOWING SEGMENTS PRODUCING DAMAGING WINDS. THE TIMING OF THE FRONT
WILL PLAY A BIG PART IN EXACTLY WHERE STRONG STORMS WILL SET UP WITH
A BETTER POTENTIAL FROM THE FINGER LAKES EASTWARD. TEMPERATURES
DURING MONDAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S PRIOR TO THE
FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
LINE OF TSRA APPROACHING THE NIAGARA FRONTIER LATE THIS EVENING. HAVE
AMENDED TAFS TO REFLECT MUCH EARLIER ARRIVAL OF STORMS. VFR EXPECTED
OUTSIDE OF TSRA WITH SOME GUSTY WINDS DEVELOPING. MVFR/IFR POSSIBLE
WITHIN TSRA. A 50KT LOW LEVEL JET PER VAD WIND PROFILES IS ALSO IN
PLACE BRINGING LOW LEVEL WIND SHEAR TO THE TAF SITES.

ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE COLD
FRONTAL PASSAGE ON MONDAY. THERE MAY BE LOWER MVFR TO IFR CONDITIONS
WITH THE STORMS...AS WELL AS THE RISK OF SEVERE CATEGORY WIND
GUSTS...BUT MOST OF THE TIME WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM MICHIGAN. THE GUSTY WINDS ACROSS THE EASTERN GREAT
LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST TO INCREASE
WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES.
SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO
COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY. A LINE OF
SHOWERS AND STRONG THUNDERSTORMS WILL ALSO WORK ACROSS THE LAKE ERIE
AND WESTERN LAKE ONTARIO WATERS AHEAD OF THE FRONT OVERNIGHT.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS
POSSIBLE. THE SEVERE THREAT FROM THESE STORMS WILL BE WIND GUSTS
NEARING OR EXCEEDING 50 KNOTS. ALONG WITH THE THREAT OF
CONVECTION...SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE
LOWER GREAT LAKES FOR THE BULK OF THE DAY. WINDS WILL TEMPORARILY
SUBSIDE ACROSS THE REGION LATE MONDAY AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH




000
FXUS61 KBUF 030020
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
820 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC COAST TONIGHT. A
STRONG COLD FRONT WILL THEN SHIFT ACROSS NEW YORK ON MONDAY WITH
STRONG TO SEVERE THUNDERSTORMS POSSIBLE THROUGH MONDAY AFTERNOON. A
COMFORTABLY COOL AIRMASS WILL THEN FOLLOW THE FRONT MONDAY NIGHT AND
SHOULD BE SETTLE IN PLACE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
RADAR AT 8PM THIS EVENING SHOWS THE REMNANTS OF A MESOSCALE
CONVECTIVE SYSTEM/BROKEN LINE OF THUNDERSTORMS ARE TRACKING EAST
ACROSS THE NORTHERN END OF LAKE ONTARIO. THE WEAKENING TREND OF THIS
CLUSTER OF THUNDERSTORMS WAS WELL FORECAST BY MESOSCALE MODELS
GIVING HIGHER CONFIDENCE TO GUIDANCE GOING THROUGH THE OVERNIGHT.
THE WEAKENING WAS BROUGHT ON AS THE STORMS TRACKED OVER A MUCH MORE
STABLE AND DRIER ENVIRONMENT RESIDING OVER LAKE ONTARIO. EXPECT A
CONTINUED WEAKENING TO THIS SWATH OF RAIN SHOWERS AS IT TRACKS EAST
OF LAKE ONTARIO TO THE NORTH COUNTY AND SAINT LAWRENCE VALLEY WITH
CHANCES OF SOME RAIN SHOWERS THIS EVENING FOR THOSE LOCATIONS.

A COLD FRONT IS FOUND WELL TO THE WEST OF NEW YORK STRETCHED ACROSS
THE U.P. OF MICHIGAN AND WISCONSIN. REGIONAL RADARS ARE SHOWING MORE
CLUSTERS OF SEVERE THUNDERSTORMS ORIENTED ACROSS MICHIGAN INTO LOWER
ONTARIO PROVINCE WITHIN AN UNSTABLE AND SHEARED ENVIRONMENT AHEAD OF
THE COLD FRONT AND IN LINE WITH A MID LEVEL SHORTWAVE TROUGH
CROSSING THE GREAT LAKES REGION. MESO GUIDANCE ALSO WEAKENS THIS
ACTIVITY THROUGH THE OVERNIGHT AS IT DRIFTS EAST TOWARD NEW YORK
WITH A CHANCE OF SHOWERS AND POSSIBLE THUNDERSTORMS LATE TONIGHT IF
IT CELLS HOLD TOGETHER LONG ENOUGH. AGAIN THESE CELLS WILL ENCOUNTER
INCREASING DRIER AND MORE STABLE AIR OVER OUR FORECAST AREA LEADING
TO JUST THE CHANCE POPS.

THE COMBINATION OF A PRESSURE GRADIENT OVER THE EASTERN GREAT LAKES
AND THE APPROACH OF A 50-60KT LOW LEVEL JET WILL BRING AN INCREASE
TO WINDS OVERNIGHT AHEAD OF THE FRONT. GUSTS TO THE 20-30 MPH RANGE
WOULD BE POSSIBLE OTHERWISE JUST MID/HIGH LEVEL CLOUD DEBRIS
DRIFTING OVERHEAD. TEMPERATURES IN MOST AREAS WILL ONLY FALL INTO
THE THE UPPER 60S OR LOWER 70S.

THE COLD FRONT WILL CROSS WESTERN NEW YORK MONDAY MORNING THEN
SHIFTING TOWARD CENTRAL NEW YORK BY THE AFTERNOON HOURS. DEWPOINT
POOLING AHEAD OF THE FRONT WILL BOOST SURFACE DEWPOINTS INTO THE
MIDDLE TO UPPER 60S. A CAPED ENVIRONMENT PER FORECAST SOUNDING SHOULD
KEEP ANY ACTIVITY TAME IN THE MORNING. LOW LEVEL CONVERGENCE ALONG
THE FRONT WILL PROVIDE LIFT WITH INCREASING INSTABILITY GOING INTO
THE AFTERNOON WITH DIURNAL HEATING. FORECASTED CAPE WILL INCREASE TO
1000-2000 J/KG WITHIN A UNIDIRECTIONALLY SHEARED ENVIRONMENT UP TO
50KTS SUPPORTING THE POTENTIAL FOR SEVERE LINER STORMS WITH POSSIBLE
BOWING SEGMENTS PRODUCING DAMAGING WINDS. THE TIMING OF THE FRONT
WILL PLAY A BIG PART IN EXACTLY WHERE STRONG STORMS WILL SET UP WITH
A BETTER POTENTIAL FROM THE FINGER LAKES EASTWARD. TEMPERATURES
DURING MONDAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S PRIOR TO THE
FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CIGS IN PLACE THROUGH THE OVERNIGHT. A 50KT LOW LEVEL JET
IS FORECAST TO DEVELOP AHEAD OF AN APPROACHING COLD FRONT SHIFTING
EAST FROM THE WESTERN GREAT LAKES. THIS LOW LEVEL JET WILL BRING A
FEW HOURS OF LOW LEVEL WIND SHEAR TO THE TAF SITES OVERNIGHT.

SOME -SHRA MAY REACH KART THIS EVENING FROM A WEAKENING CLUSTER OF
CELLS OVER THE EAST END OF LAKE ONTARIO OTHERWISE DESPITE CURRENT
RADAR IMAGERY SHOWING STRONG STORMS ACROSS MICHIGAN AND NORTH OF
LAKE ERIE...GUIDANCE WEAKENS THESE FEATURES OVERNIGHT LEADING TO DRY
FORECAST OVERNIGHT

SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON
MONDAY. THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE
STORMS...AS WELL AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT
MOST OF THE TIME WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM THE WESTERN GREAT LAKES. THE GUSTY WINDS ACROSS THE
EASTERN GREAT LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST
TO INCREASE WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET
AT TIMES. SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND
ONTARIO TO COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH





000
FXUS61 KBUF 030020
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
820 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC COAST TONIGHT. A
STRONG COLD FRONT WILL THEN SHIFT ACROSS NEW YORK ON MONDAY WITH
STRONG TO SEVERE THUNDERSTORMS POSSIBLE THROUGH MONDAY AFTERNOON. A
COMFORTABLY COOL AIRMASS WILL THEN FOLLOW THE FRONT MONDAY NIGHT AND
SHOULD BE SETTLE IN PLACE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
RADAR AT 8PM THIS EVENING SHOWS THE REMNANTS OF A MESOSCALE
CONVECTIVE SYSTEM/BROKEN LINE OF THUNDERSTORMS ARE TRACKING EAST
ACROSS THE NORTHERN END OF LAKE ONTARIO. THE WEAKENING TREND OF THIS
CLUSTER OF THUNDERSTORMS WAS WELL FORECAST BY MESOSCALE MODELS
GIVING HIGHER CONFIDENCE TO GUIDANCE GOING THROUGH THE OVERNIGHT.
THE WEAKENING WAS BROUGHT ON AS THE STORMS TRACKED OVER A MUCH MORE
STABLE AND DRIER ENVIRONMENT RESIDING OVER LAKE ONTARIO. EXPECT A
CONTINUED WEAKENING TO THIS SWATH OF RAIN SHOWERS AS IT TRACKS EAST
OF LAKE ONTARIO TO THE NORTH COUNTY AND SAINT LAWRENCE VALLEY WITH
CHANCES OF SOME RAIN SHOWERS THIS EVENING FOR THOSE LOCATIONS.

A COLD FRONT IS FOUND WELL TO THE WEST OF NEW YORK STRETCHED ACROSS
THE U.P. OF MICHIGAN AND WISCONSIN. REGIONAL RADARS ARE SHOWING MORE
CLUSTERS OF SEVERE THUNDERSTORMS ORIENTED ACROSS MICHIGAN INTO LOWER
ONTARIO PROVINCE WITHIN AN UNSTABLE AND SHEARED ENVIRONMENT AHEAD OF
THE COLD FRONT AND IN LINE WITH A MID LEVEL SHORTWAVE TROUGH
CROSSING THE GREAT LAKES REGION. MESO GUIDANCE ALSO WEAKENS THIS
ACTIVITY THROUGH THE OVERNIGHT AS IT DRIFTS EAST TOWARD NEW YORK
WITH A CHANCE OF SHOWERS AND POSSIBLE THUNDERSTORMS LATE TONIGHT IF
IT CELLS HOLD TOGETHER LONG ENOUGH. AGAIN THESE CELLS WILL ENCOUNTER
INCREASING DRIER AND MORE STABLE AIR OVER OUR FORECAST AREA LEADING
TO JUST THE CHANCE POPS.

THE COMBINATION OF A PRESSURE GRADIENT OVER THE EASTERN GREAT LAKES
AND THE APPROACH OF A 50-60KT LOW LEVEL JET WILL BRING AN INCREASE
TO WINDS OVERNIGHT AHEAD OF THE FRONT. GUSTS TO THE 20-30 MPH RANGE
WOULD BE POSSIBLE OTHERWISE JUST MID/HIGH LEVEL CLOUD DEBRIS
DRIFTING OVERHEAD. TEMPERATURES IN MOST AREAS WILL ONLY FALL INTO
THE THE UPPER 60S OR LOWER 70S.

THE COLD FRONT WILL CROSS WESTERN NEW YORK MONDAY MORNING THEN
SHIFTING TOWARD CENTRAL NEW YORK BY THE AFTERNOON HOURS. DEWPOINT
POOLING AHEAD OF THE FRONT WILL BOOST SURFACE DEWPOINTS INTO THE
MIDDLE TO UPPER 60S. A CAPED ENVIRONMENT PER FORECAST SOUNDING SHOULD
KEEP ANY ACTIVITY TAME IN THE MORNING. LOW LEVEL CONVERGENCE ALONG
THE FRONT WILL PROVIDE LIFT WITH INCREASING INSTABILITY GOING INTO
THE AFTERNOON WITH DIURNAL HEATING. FORECASTED CAPE WILL INCREASE TO
1000-2000 J/KG WITHIN A UNIDIRECTIONALLY SHEARED ENVIRONMENT UP TO
50KTS SUPPORTING THE POTENTIAL FOR SEVERE LINER STORMS WITH POSSIBLE
BOWING SEGMENTS PRODUCING DAMAGING WINDS. THE TIMING OF THE FRONT
WILL PLAY A BIG PART IN EXACTLY WHERE STRONG STORMS WILL SET UP WITH
A BETTER POTENTIAL FROM THE FINGER LAKES EASTWARD. TEMPERATURES
DURING MONDAY WILL CLIMB TO THE UPPER 70S TO LOWER 80S PRIOR TO THE
FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CIGS IN PLACE THROUGH THE OVERNIGHT. A 50KT LOW LEVEL JET
IS FORECAST TO DEVELOP AHEAD OF AN APPROACHING COLD FRONT SHIFTING
EAST FROM THE WESTERN GREAT LAKES. THIS LOW LEVEL JET WILL BRING A
FEW HOURS OF LOW LEVEL WIND SHEAR TO THE TAF SITES OVERNIGHT.

SOME -SHRA MAY REACH KART THIS EVENING FROM A WEAKENING CLUSTER OF
CELLS OVER THE EAST END OF LAKE ONTARIO OTHERWISE DESPITE CURRENT
RADAR IMAGERY SHOWING STRONG STORMS ACROSS MICHIGAN AND NORTH OF
LAKE ERIE...GUIDANCE WEAKENS THESE FEATURES OVERNIGHT LEADING TO DRY
FORECAST OVERNIGHT

SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON
MONDAY. THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE
STORMS...AS WELL AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT
MOST OF THE TIME WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM THE WESTERN GREAT LAKES. THE GUSTY WINDS ACROSS THE
EASTERN GREAT LAKES AHEAD OF THE APPROACHING COLD FRONT ARE FORECAST
TO INCREASE WAVES ON THE NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET
AT TIMES. SMALL CRAFT ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND
ONTARIO TO COVER FOR THESE HIGHER WINDS AND WAVES THROUGH MONDAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042>045.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH




000
FXUS61 KBUF 022147
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
547 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC COAST TONIGHT. A
STRONG COLD FRONT WILL THEN SHIFT ACROSS NEW YORK ON MONDAY WITH
STRONG TO SEVERE THUNDERSTORMS POSSIBLE THROUGH MONDAY AFTERNOON. A
COMFORTABLY COOL AIRMASS WILL THEN FOLLOW THE FRONT MONDAY NIGHT AND
SHOULD BE SETTLE IN PLACE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
HIGH PRESSURE CENTERED ACROSS THE MID-ATLANTIC REGION WILL MOVE OFF
THE COAST TONIGHT AS A COLD FRONT STRETCHED ACROSS THE WESTERN GREAT
LAKES APPROACHES THE FORECAST AREA. A TIGHT PRESSURE GRADIENT
BETWEEN THESE TWO FEATURES WILL KEEP BREEZY TO GUSTY WINDS WITH
MAINLY CLEAR TO PARTLY CLOUDY SKIES MOST OF THIS EVENING. THE
BUFFALO RADAR IS SHOWING A STRONG BOWING CONVECTIVE SEGMENT JUST
WEST OF LAKE ONTARIO APPROACHING THE GREATER TORONTO AREA WHICH WAS
TRIGGERED BY A SHORTWAVE TROUGH SHIFTING ACROSS A BROAD MID-LEVEL
TROUGH RUNNING WEST TO EAST ACROSS THE GREAT LAKES. RECENT MESOSCALE
GUIDANCE INCLUDING THE HRRR/WRF/SSEO AND NAM ALL GENERALLY DISSIPATE
THIS LINE OF STORMS AS IT TRACKS ACROSS LAKE ONTARIO OVERNIGHT. THIS
DISSIPATION IS LIKELY DUE TO THE CONVECTION MOVING INTO A MORE
STABLE AND MUCH DIRER AIRMASS IN PLACE ACROSS UPSTATE NEW YORK AND
LAKE ONTARIO ALONG WITH ENCOUNTERING STRONG PARALLEL WIND SHEAR FROM
A LOW LEVEL JET FORECAST TO INCREASE AHEAD OF THE COLD FRONT.

THE FORECAST FEATURES A LOWER END CHANCE OF SOME SHOWERS AND
THUNDERSTORMS POSSIBLY REACHING WESTERN NY TOWARD MIDNIGHT FAVORING
THE MESOSCALE MODELS BUT THE BULK OF SHOWER AND THUNDERSTORM
ACTIVITY SHOULD HOLD OFF UNTIL THE LATE OVERNIGHT HOURS...CLOSER TO
DAYBREAK WHEN THE COLD FRONT APPROACHES CLOSER TO THE FORECAST AREA.
THE GUSTY/BREEZY WINDS OVERNIGHT WILL PREVENT TEMPERATURES IN MOST
AREAS FROM FALLING BELOW THE UPPER 60S OR LOWER 70S. AS THE PRESSURE
GRADIENT INCREASES OVERNIGHT...WINDS ACROSS THE HIGHER ELEVATIONS OF
THE SOUTHERN TIER AND CLOSE TO LAKE ERIE COULD GUST TO 35 MPH.

THE COLD FRONT WILL CONTINUE ACROSS THE REGION DURING THE DAY ON
MONDAY. DEWPOINT POOLING AHEAD OF THE FRONT WILL BOOST SURFACE
DEWPOINTS INTO THE MIDDLE TO UPPER 60S...MID AND UPPER LEVEL TEMPS
WILL FALL SLIGHTLY WITH THE APPROACH OF THE UPPER TROUGH ...AND LOW
LEVEL CONVERGENCE ALONG THE FRONT WILL PROVIDE LIFT AND INSTABILITY
TO SUPPORT CONVECTION. STRONG WINDS TOPPING THE BOUNDARY LAYER EARLY
MONDAY WILL ALSO PROVIDE A SEVERE WEATHER THREAT WITH DAMAGING WIND
RISK...LESSENING AS THE STRONG WINDS MOVE FARTHER ALOFT BEHIND THE
FRONT. TEMPERATURES DURING MONDAY WILL CLIMB TO THE UPPER 70S TO
LOWER 80S PRIOR TO THE FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CIGS IN PLACE THROUGH AT LEAST THIS EVENING. A STRONG LINE
OF STORMS NEAR CYYZ SHOULD REMAIN NORTH OF THE FORECAST AREA. A 50KT
LOW LEVEL JET IS FORECAST TO DEVELOP AHEAD OF AN APPROACHING COLD
FRONT SHIFTING EAST FROM THE WESTERN GREAT LAKES. THIS LOW LEVEL JET
WILL BRING A FEW HOURS OF LOW LEVEL WIND SHEAR TO THE TAF SITES
OVERNIGHT.

WHILE VFR CONDITIONS WILL REMAIN IN PLACE FOR MUCH OF THE
NIGHT...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS DEVELOPING AHEAD
OF THE APPROACHING COLD FRONT COULD IMPACT THE REGION CLOSER TO 12Z
MONDAY.

THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON MONDAY.
THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE STORMS...AS WELL
AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT MOST OF THE TIME
WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM THE WESTERN GREAT LAKES. AN AREA OF STRONG
THUNDERSTORMS OUT WELL AHEAD OF THE FRONT WILL MOVE ACROSS LAKE
ONTARIO TRACKING EAST TOWARD THE SAINT LAWRENCE RIVER THIS EVENING.
THIS LINE OF STORMS IS FORECAST TO WEAKEN/DISSIPATE AS IT MOVES
ACROSS THE LAKE BUT DOES BRING THE POTENTIAL FOR VERY STRONG WIND
GUSTS AND LIGHTNING.

THE GUSTY WINDS ACROSS THE EASTERN GREAT LAKES AHEAD OF THE
APPROACHING COLD FRONT ARE FORECAST TO INCREASE WAVES ON THE
NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES. SMALL CRAFT
ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO COVER FOR
THESE HIGHER WINDS AND WAVES THROUGH MONDAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH




000
FXUS61 KBUF 022147
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
547 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC COAST TONIGHT. A
STRONG COLD FRONT WILL THEN SHIFT ACROSS NEW YORK ON MONDAY WITH
STRONG TO SEVERE THUNDERSTORMS POSSIBLE THROUGH MONDAY AFTERNOON. A
COMFORTABLY COOL AIRMASS WILL THEN FOLLOW THE FRONT MONDAY NIGHT AND
SHOULD BE SETTLE IN PLACE FOR THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
HIGH PRESSURE CENTERED ACROSS THE MID-ATLANTIC REGION WILL MOVE OFF
THE COAST TONIGHT AS A COLD FRONT STRETCHED ACROSS THE WESTERN GREAT
LAKES APPROACHES THE FORECAST AREA. A TIGHT PRESSURE GRADIENT
BETWEEN THESE TWO FEATURES WILL KEEP BREEZY TO GUSTY WINDS WITH
MAINLY CLEAR TO PARTLY CLOUDY SKIES MOST OF THIS EVENING. THE
BUFFALO RADAR IS SHOWING A STRONG BOWING CONVECTIVE SEGMENT JUST
WEST OF LAKE ONTARIO APPROACHING THE GREATER TORONTO AREA WHICH WAS
TRIGGERED BY A SHORTWAVE TROUGH SHIFTING ACROSS A BROAD MID-LEVEL
TROUGH RUNNING WEST TO EAST ACROSS THE GREAT LAKES. RECENT MESOSCALE
GUIDANCE INCLUDING THE HRRR/WRF/SSEO AND NAM ALL GENERALLY DISSIPATE
THIS LINE OF STORMS AS IT TRACKS ACROSS LAKE ONTARIO OVERNIGHT. THIS
DISSIPATION IS LIKELY DUE TO THE CONVECTION MOVING INTO A MORE
STABLE AND MUCH DIRER AIRMASS IN PLACE ACROSS UPSTATE NEW YORK AND
LAKE ONTARIO ALONG WITH ENCOUNTERING STRONG PARALLEL WIND SHEAR FROM
A LOW LEVEL JET FORECAST TO INCREASE AHEAD OF THE COLD FRONT.

THE FORECAST FEATURES A LOWER END CHANCE OF SOME SHOWERS AND
THUNDERSTORMS POSSIBLY REACHING WESTERN NY TOWARD MIDNIGHT FAVORING
THE MESOSCALE MODELS BUT THE BULK OF SHOWER AND THUNDERSTORM
ACTIVITY SHOULD HOLD OFF UNTIL THE LATE OVERNIGHT HOURS...CLOSER TO
DAYBREAK WHEN THE COLD FRONT APPROACHES CLOSER TO THE FORECAST AREA.
THE GUSTY/BREEZY WINDS OVERNIGHT WILL PREVENT TEMPERATURES IN MOST
AREAS FROM FALLING BELOW THE UPPER 60S OR LOWER 70S. AS THE PRESSURE
GRADIENT INCREASES OVERNIGHT...WINDS ACROSS THE HIGHER ELEVATIONS OF
THE SOUTHERN TIER AND CLOSE TO LAKE ERIE COULD GUST TO 35 MPH.

THE COLD FRONT WILL CONTINUE ACROSS THE REGION DURING THE DAY ON
MONDAY. DEWPOINT POOLING AHEAD OF THE FRONT WILL BOOST SURFACE
DEWPOINTS INTO THE MIDDLE TO UPPER 60S...MID AND UPPER LEVEL TEMPS
WILL FALL SLIGHTLY WITH THE APPROACH OF THE UPPER TROUGH ...AND LOW
LEVEL CONVERGENCE ALONG THE FRONT WILL PROVIDE LIFT AND INSTABILITY
TO SUPPORT CONVECTION. STRONG WINDS TOPPING THE BOUNDARY LAYER EARLY
MONDAY WILL ALSO PROVIDE A SEVERE WEATHER THREAT WITH DAMAGING WIND
RISK...LESSENING AS THE STRONG WINDS MOVE FARTHER ALOFT BEHIND THE
FRONT. TEMPERATURES DURING MONDAY WILL CLIMB TO THE UPPER 70S TO
LOWER 80S PRIOR TO THE FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CIGS IN PLACE THROUGH AT LEAST THIS EVENING. A STRONG LINE
OF STORMS NEAR CYYZ SHOULD REMAIN NORTH OF THE FORECAST AREA. A 50KT
LOW LEVEL JET IS FORECAST TO DEVELOP AHEAD OF AN APPROACHING COLD
FRONT SHIFTING EAST FROM THE WESTERN GREAT LAKES. THIS LOW LEVEL JET
WILL BRING A FEW HOURS OF LOW LEVEL WIND SHEAR TO THE TAF SITES
OVERNIGHT.

WHILE VFR CONDITIONS WILL REMAIN IN PLACE FOR MUCH OF THE
NIGHT...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS DEVELOPING AHEAD
OF THE APPROACHING COLD FRONT COULD IMPACT THE REGION CLOSER TO 12Z
MONDAY.

THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON MONDAY.
THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE STORMS...AS WELL
AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT MOST OF THE TIME
WILL BE VFR.

OUTLOOK...

MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW
SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF
THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS WILL CONTINUE TO GUST TOWARD 20 KNOTS TONIGHT AS A
TIGHT PRESSURE GRADIENT IS IN PLACE AHEAD OF A STRONG COLD FRONT
APPROACHING FROM THE WESTERN GREAT LAKES. AN AREA OF STRONG
THUNDERSTORMS OUT WELL AHEAD OF THE FRONT WILL MOVE ACROSS LAKE
ONTARIO TRACKING EAST TOWARD THE SAINT LAWRENCE RIVER THIS EVENING.
THIS LINE OF STORMS IS FORECAST TO WEAKEN/DISSIPATE AS IT MOVES
ACROSS THE LAKE BUT DOES BRING THE POTENTIAL FOR VERY STRONG WIND
GUSTS AND LIGHTNING.

THE GUSTY WINDS ACROSS THE EASTERN GREAT LAKES AHEAD OF THE
APPROACHING COLD FRONT ARE FORECAST TO INCREASE WAVES ON THE
NORTHEASTERN END OF LAKE ERIE TOWARD 6 FEET AT TIMES. SMALL CRAFT
ADVISORIES ARE IN PLACE ACROSS LAKE ERIE AND ONTARIO TO COVER FOR
THESE HIGHER WINDS AND WAVES THROUGH MONDAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042.

&&

$$

SYNOPSIS...SMITH/WCH
NEAR TERM...SMITH/WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WCH
MARINE...SMITH/WCH





000
FXUS61 KBUF 021944
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
344 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC
COAST...THEN A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR
WEATHER LATER TONIGHT AND MONDAY. STRONG TO SEVERE STORMS WILL BE
POSSIBLE AS THE COLD FRONT MOVES EAST ACROSS OUR REGION THROUGH
MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL FOLLOW THE FRONT
MONDAY NIGHT AND SHOULD BE IN PLACE FOR AT LEAST THE REMAINDER OF
THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
HIGH PRESSURE SOUTH OF THE REGION WILL MOVE OFF THE MID ATLANTIC
COAST TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST. CONVECTION
ALONG THE FRONT HAS BEEN ACTIVE ALL DAY ACROSS NORTHERN WISCONSIN
AND NORTHERN MICHIGAN...AND HAS BEEN MOVING EASTWARD WITH THE FRONT.
DEWPOINTS ACROSS OUR AREA ARE IN THE LOWER TO MID 50S AT MID
AFTERNOON...BUT WILL BE ON THE RISE AS SOUTHWESTERLY WINDS ADVECT
HIGHER DEWPOINT AIRMASS THIS EVENING AND TONIGHT. THE UPSTREAM
CONVECTION WILL NOT LIKELY SPREAD INTO THE DRIER AIR CURRENTLY IN
PLACE...BUT WITH INCREASINGLY MOIST AIR WILL COME HIGHER POPS LATER
TONIGHT. SOME SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD
APPROACH WESTERN NY AND THE WATERS OF LAKE ERIE AND WESTERN LAKE
ONTARIO...BUT THE BULK OF THE PRECIPITATION WILL HOLD OFF UNTIL THE
LATE OVERNIGHT HOURS...CLOSER TO DAYBREAK. WITH THE SOUTHWESTERLY TO
SOUTHERLY WINDS TONIGHT...IT WILL BE A BREEZY AND WARM NIGHT. THE
STRENGTHENING WINDS WILL PREVENT TEMPERATURES IN MOST AREAS FROM
FALLING BELOW THE UPPER 60S OR LOWER 70S. AS THE PRESSURE GRADIENT
INCREASES OVERNIGHT...WINDS ACROSS THE HIGHER ELEVATIONS OF THE
SOUTHERN TIER AND CLOSE TO LAKE ERIE COULD GUST TO 35 MPH.

THE COLD FRONT WILL CONTINUE ACROSS THE REGION DURING THE DAY ON
MONDAY. DEWPOINT POOLING AHEAD OF THE FRONT WILL BOOST SURFACE
DEWPOINTS INTO THE MIDDLE TO UPPER 60S...MID AND UPPER LEVEL TEMPS
WILL FALL SLIGHTLY WITH THE APPROACH OF THE UPPER TROUGH ...AND LOW
LEVEL CONVERGENCE ALONG THE FRONT WILL PROVIDE LIFT AND INSTABILITY
TO SUPPORT CONVECTION. STRONG WINDS TOPPING THE BOUNDARY LAYER EARLY
MONDAY WILL ALSO PROVIDE A SEVERE WEATHER THREAT WITH DAMAGING WIND
RISK...LESSENING AS THE STRONG WINDS MOVE FARTHER ALOFT BEHIND THE
FRONT. TEMPERATURES DURING MONDAY WILL CLIMB TO THE UPPER 70S TO
LOWER 80S PRIOR TO THE FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR THIS
WILL COME OVER THE HILLS OF THE SOUTHERN TIER TO THE FINGER LAKES
REGION WHERE THE STRONGER WINDS ALOFT WILL HAVE A LOWER CHANCE OF
MIXING TO THE SFC.

THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON MONDAY.
THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE STORMS...AS WELL
AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT MOST OF THE TIME
WILL BE VFR.

OUTLOOK...

SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS SUSTAINED 10 TO 15 KNOTS WITH GUSTS TO 20 KNOTS WILL
INCREASE ENOUGH TO 15 TO 20 KNOT GUSTING 25 KNOTS THIS AFTERNOON...
SUFFICIENT FOR SMALL CRAFT ADVISORIES ON LAKE ERIE...NIAGARA RIVER
AND WESTERN LAKE ONTARIO.

CONDITIONS WILL FURTHER DETERIORATE TONIGHT AS A STRONG COLD FRONT
WILL TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES AND THE
SURFACE PRESSURE GRADIENT INCREASES. WINDS WILL INCREASE TO NEAR 30
KNOTS ON LAKE ERIE AND PARTS OF WESTERN LAKE ONTARIO LATER
TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING AS WELL. WAVES
ON NORTHEASTERN LAKE ERIE WILL LIKELY REACH 6 FEET AT TIMES BY
DAYBREAK...WITH WIDESPREAD COVERAGE OF WAVES AVERAGING MORE THAN 4
FEET BY 06Z.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042.

&&

$$

SYNOPSIS...WCH
NEAR TERM...WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...WCH
MARINE...WCH




000
FXUS61 KBUF 021944
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
344 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC
COAST...THEN A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR
WEATHER LATER TONIGHT AND MONDAY. STRONG TO SEVERE STORMS WILL BE
POSSIBLE AS THE COLD FRONT MOVES EAST ACROSS OUR REGION THROUGH
MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL FOLLOW THE FRONT
MONDAY NIGHT AND SHOULD BE IN PLACE FOR AT LEAST THE REMAINDER OF
THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
HIGH PRESSURE SOUTH OF THE REGION WILL MOVE OFF THE MID ATLANTIC
COAST TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST. CONVECTION
ALONG THE FRONT HAS BEEN ACTIVE ALL DAY ACROSS NORTHERN WISCONSIN
AND NORTHERN MICHIGAN...AND HAS BEEN MOVING EASTWARD WITH THE FRONT.
DEWPOINTS ACROSS OUR AREA ARE IN THE LOWER TO MID 50S AT MID
AFTERNOON...BUT WILL BE ON THE RISE AS SOUTHWESTERLY WINDS ADVECT
HIGHER DEWPOINT AIRMASS THIS EVENING AND TONIGHT. THE UPSTREAM
CONVECTION WILL NOT LIKELY SPREAD INTO THE DRIER AIR CURRENTLY IN
PLACE...BUT WITH INCREASINGLY MOIST AIR WILL COME HIGHER POPS LATER
TONIGHT. SOME SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD
APPROACH WESTERN NY AND THE WATERS OF LAKE ERIE AND WESTERN LAKE
ONTARIO...BUT THE BULK OF THE PRECIPITATION WILL HOLD OFF UNTIL THE
LATE OVERNIGHT HOURS...CLOSER TO DAYBREAK. WITH THE SOUTHWESTERLY TO
SOUTHERLY WINDS TONIGHT...IT WILL BE A BREEZY AND WARM NIGHT. THE
STRENGTHENING WINDS WILL PREVENT TEMPERATURES IN MOST AREAS FROM
FALLING BELOW THE UPPER 60S OR LOWER 70S. AS THE PRESSURE GRADIENT
INCREASES OVERNIGHT...WINDS ACROSS THE HIGHER ELEVATIONS OF THE
SOUTHERN TIER AND CLOSE TO LAKE ERIE COULD GUST TO 35 MPH.

THE COLD FRONT WILL CONTINUE ACROSS THE REGION DURING THE DAY ON
MONDAY. DEWPOINT POOLING AHEAD OF THE FRONT WILL BOOST SURFACE
DEWPOINTS INTO THE MIDDLE TO UPPER 60S...MID AND UPPER LEVEL TEMPS
WILL FALL SLIGHTLY WITH THE APPROACH OF THE UPPER TROUGH ...AND LOW
LEVEL CONVERGENCE ALONG THE FRONT WILL PROVIDE LIFT AND INSTABILITY
TO SUPPORT CONVECTION. STRONG WINDS TOPPING THE BOUNDARY LAYER EARLY
MONDAY WILL ALSO PROVIDE A SEVERE WEATHER THREAT WITH DAMAGING WIND
RISK...LESSENING AS THE STRONG WINDS MOVE FARTHER ALOFT BEHIND THE
FRONT. TEMPERATURES DURING MONDAY WILL CLIMB TO THE UPPER 70S TO
LOWER 80S PRIOR TO THE FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR THIS
WILL COME OVER THE HILLS OF THE SOUTHERN TIER TO THE FINGER LAKES
REGION WHERE THE STRONGER WINDS ALOFT WILL HAVE A LOWER CHANCE OF
MIXING TO THE SFC.

THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON MONDAY.
THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE STORMS...AS WELL
AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT MOST OF THE TIME
WILL BE VFR.

OUTLOOK...

SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS SUSTAINED 10 TO 15 KNOTS WITH GUSTS TO 20 KNOTS WILL
INCREASE ENOUGH TO 15 TO 20 KNOT GUSTING 25 KNOTS THIS AFTERNOON...
SUFFICIENT FOR SMALL CRAFT ADVISORIES ON LAKE ERIE...NIAGARA RIVER
AND WESTERN LAKE ONTARIO.

CONDITIONS WILL FURTHER DETERIORATE TONIGHT AS A STRONG COLD FRONT
WILL TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES AND THE
SURFACE PRESSURE GRADIENT INCREASES. WINDS WILL INCREASE TO NEAR 30
KNOTS ON LAKE ERIE AND PARTS OF WESTERN LAKE ONTARIO LATER
TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING AS WELL. WAVES
ON NORTHEASTERN LAKE ERIE WILL LIKELY REACH 6 FEET AT TIMES BY
DAYBREAK...WITH WIDESPREAD COVERAGE OF WAVES AVERAGING MORE THAN 4
FEET BY 06Z.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042.

&&

$$

SYNOPSIS...WCH
NEAR TERM...WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...WCH
MARINE...WCH





000
FXUS61 KBUF 021944
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
344 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC
COAST...THEN A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR
WEATHER LATER TONIGHT AND MONDAY. STRONG TO SEVERE STORMS WILL BE
POSSIBLE AS THE COLD FRONT MOVES EAST ACROSS OUR REGION THROUGH
MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL FOLLOW THE FRONT
MONDAY NIGHT AND SHOULD BE IN PLACE FOR AT LEAST THE REMAINDER OF
THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
HIGH PRESSURE SOUTH OF THE REGION WILL MOVE OFF THE MID ATLANTIC
COAST TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST. CONVECTION
ALONG THE FRONT HAS BEEN ACTIVE ALL DAY ACROSS NORTHERN WISCONSIN
AND NORTHERN MICHIGAN...AND HAS BEEN MOVING EASTWARD WITH THE FRONT.
DEWPOINTS ACROSS OUR AREA ARE IN THE LOWER TO MID 50S AT MID
AFTERNOON...BUT WILL BE ON THE RISE AS SOUTHWESTERLY WINDS ADVECT
HIGHER DEWPOINT AIRMASS THIS EVENING AND TONIGHT. THE UPSTREAM
CONVECTION WILL NOT LIKELY SPREAD INTO THE DRIER AIR CURRENTLY IN
PLACE...BUT WITH INCREASINGLY MOIST AIR WILL COME HIGHER POPS LATER
TONIGHT. SOME SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD
APPROACH WESTERN NY AND THE WATERS OF LAKE ERIE AND WESTERN LAKE
ONTARIO...BUT THE BULK OF THE PRECIPITATION WILL HOLD OFF UNTIL THE
LATE OVERNIGHT HOURS...CLOSER TO DAYBREAK. WITH THE SOUTHWESTERLY TO
SOUTHERLY WINDS TONIGHT...IT WILL BE A BREEZY AND WARM NIGHT. THE
STRENGTHENING WINDS WILL PREVENT TEMPERATURES IN MOST AREAS FROM
FALLING BELOW THE UPPER 60S OR LOWER 70S. AS THE PRESSURE GRADIENT
INCREASES OVERNIGHT...WINDS ACROSS THE HIGHER ELEVATIONS OF THE
SOUTHERN TIER AND CLOSE TO LAKE ERIE COULD GUST TO 35 MPH.

THE COLD FRONT WILL CONTINUE ACROSS THE REGION DURING THE DAY ON
MONDAY. DEWPOINT POOLING AHEAD OF THE FRONT WILL BOOST SURFACE
DEWPOINTS INTO THE MIDDLE TO UPPER 60S...MID AND UPPER LEVEL TEMPS
WILL FALL SLIGHTLY WITH THE APPROACH OF THE UPPER TROUGH ...AND LOW
LEVEL CONVERGENCE ALONG THE FRONT WILL PROVIDE LIFT AND INSTABILITY
TO SUPPORT CONVECTION. STRONG WINDS TOPPING THE BOUNDARY LAYER EARLY
MONDAY WILL ALSO PROVIDE A SEVERE WEATHER THREAT WITH DAMAGING WIND
RISK...LESSENING AS THE STRONG WINDS MOVE FARTHER ALOFT BEHIND THE
FRONT. TEMPERATURES DURING MONDAY WILL CLIMB TO THE UPPER 70S TO
LOWER 80S PRIOR TO THE FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR THIS
WILL COME OVER THE HILLS OF THE SOUTHERN TIER TO THE FINGER LAKES
REGION WHERE THE STRONGER WINDS ALOFT WILL HAVE A LOWER CHANCE OF
MIXING TO THE SFC.

THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON MONDAY.
THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE STORMS...AS WELL
AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT MOST OF THE TIME
WILL BE VFR.

OUTLOOK...

SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS SUSTAINED 10 TO 15 KNOTS WITH GUSTS TO 20 KNOTS WILL
INCREASE ENOUGH TO 15 TO 20 KNOT GUSTING 25 KNOTS THIS AFTERNOON...
SUFFICIENT FOR SMALL CRAFT ADVISORIES ON LAKE ERIE...NIAGARA RIVER
AND WESTERN LAKE ONTARIO.

CONDITIONS WILL FURTHER DETERIORATE TONIGHT AS A STRONG COLD FRONT
WILL TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES AND THE
SURFACE PRESSURE GRADIENT INCREASES. WINDS WILL INCREASE TO NEAR 30
KNOTS ON LAKE ERIE AND PARTS OF WESTERN LAKE ONTARIO LATER
TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING AS WELL. WAVES
ON NORTHEASTERN LAKE ERIE WILL LIKELY REACH 6 FEET AT TIMES BY
DAYBREAK...WITH WIDESPREAD COVERAGE OF WAVES AVERAGING MORE THAN 4
FEET BY 06Z.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042.

&&

$$

SYNOPSIS...WCH
NEAR TERM...WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...WCH
MARINE...WCH





000
FXUS61 KBUF 021944
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
344 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE MID ATLANTIC
COAST...THEN A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR
WEATHER LATER TONIGHT AND MONDAY. STRONG TO SEVERE STORMS WILL BE
POSSIBLE AS THE COLD FRONT MOVES EAST ACROSS OUR REGION THROUGH
MONDAY AFTERNOON. A COMFORTABLY COOL AIRMASS WILL FOLLOW THE FRONT
MONDAY NIGHT AND SHOULD BE IN PLACE FOR AT LEAST THE REMAINDER OF
THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
HIGH PRESSURE SOUTH OF THE REGION WILL MOVE OFF THE MID ATLANTIC
COAST TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST. CONVECTION
ALONG THE FRONT HAS BEEN ACTIVE ALL DAY ACROSS NORTHERN WISCONSIN
AND NORTHERN MICHIGAN...AND HAS BEEN MOVING EASTWARD WITH THE FRONT.
DEWPOINTS ACROSS OUR AREA ARE IN THE LOWER TO MID 50S AT MID
AFTERNOON...BUT WILL BE ON THE RISE AS SOUTHWESTERLY WINDS ADVECT
HIGHER DEWPOINT AIRMASS THIS EVENING AND TONIGHT. THE UPSTREAM
CONVECTION WILL NOT LIKELY SPREAD INTO THE DRIER AIR CURRENTLY IN
PLACE...BUT WITH INCREASINGLY MOIST AIR WILL COME HIGHER POPS LATER
TONIGHT. SOME SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD
APPROACH WESTERN NY AND THE WATERS OF LAKE ERIE AND WESTERN LAKE
ONTARIO...BUT THE BULK OF THE PRECIPITATION WILL HOLD OFF UNTIL THE
LATE OVERNIGHT HOURS...CLOSER TO DAYBREAK. WITH THE SOUTHWESTERLY TO
SOUTHERLY WINDS TONIGHT...IT WILL BE A BREEZY AND WARM NIGHT. THE
STRENGTHENING WINDS WILL PREVENT TEMPERATURES IN MOST AREAS FROM
FALLING BELOW THE UPPER 60S OR LOWER 70S. AS THE PRESSURE GRADIENT
INCREASES OVERNIGHT...WINDS ACROSS THE HIGHER ELEVATIONS OF THE
SOUTHERN TIER AND CLOSE TO LAKE ERIE COULD GUST TO 35 MPH.

THE COLD FRONT WILL CONTINUE ACROSS THE REGION DURING THE DAY ON
MONDAY. DEWPOINT POOLING AHEAD OF THE FRONT WILL BOOST SURFACE
DEWPOINTS INTO THE MIDDLE TO UPPER 60S...MID AND UPPER LEVEL TEMPS
WILL FALL SLIGHTLY WITH THE APPROACH OF THE UPPER TROUGH ...AND LOW
LEVEL CONVERGENCE ALONG THE FRONT WILL PROVIDE LIFT AND INSTABILITY
TO SUPPORT CONVECTION. STRONG WINDS TOPPING THE BOUNDARY LAYER EARLY
MONDAY WILL ALSO PROVIDE A SEVERE WEATHER THREAT WITH DAMAGING WIND
RISK...LESSENING AS THE STRONG WINDS MOVE FARTHER ALOFT BEHIND THE
FRONT. TEMPERATURES DURING MONDAY WILL CLIMB TO THE UPPER 70S TO
LOWER 80S PRIOR TO THE FRONTAL PASSAGE.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
WATER VAPOR IMAGERY THIS AFTERNOON NICELY DISPLAYS A SHORTWAVE
TROUGH OF LOW PRESSURE REACHING NORTHERN MINNESOTA. THIS SHORTWAVE
WILL BE FORCING A SURFACE COLD FRONT EASTWARD ACROSS OUR REGION
MONDAY NIGHT. EXPECT SHOWERS AND THUNDERSTORMS TO END THROUGH THE
EVENING HOURS WITH THE PASSAGE OF THE COLD FRONT AND LOSS OF
DAYTIME INSTABILITY.

THIS SHORTWAVE TROUGH WILL ALSO DRAW A PERSISTENT UPPER LEVEL LOW
OVER EASTERN CANADA SOUTHWARD. ON TUESDAY A POOL OF COOL AIR ALOFT
WILL BE RESIDING OVER SOUTHERN CANADA AND THE GREAT LAKES REGION.
STEEPENING LAPSE RATES THROUGH THE DAY TUESDAY WILL LIKELY BRING
SCATTERED RAIN SHOWERS THROUGH THE PEAK HEATING OF THE AFTERNOON AND
EARLY EVENING HOURS. THIS COOL AIR ALOFT MAY EVEN BRING SOME LAKE
ENHANCED RAIN SHOWERS TO SE AND E OF LAKE ONTARIO WHERE +6 TO +8C AT
850 HPA WILL BE FLOWING OVER A +22C OR SO LAKE TEMPERATURE.

ON WEDNESDAY THE UPPER LEVEL LOW WILL REMAIN NEARBY THE GREAT LAKES
REGION...HOWEVER LOW LEVEL MOISTURE WILL BE MUCH LESS. EVEN THOUGH
INSTABILITY WILL AGAIN INCREASE THROUGH THE AFTERNOON HOURS THE
LESS PLENTIFUL MOISTURE WITHIN THE ATMOSPHERE SHOULD DECREASE THE
AMOUNT OF AFTERNOON SHOWERS. GREATEST CHANCES FOR A SHOWER WEDNESDAY
WILL BE ACROSS OUR EASTERN ZONES WHICH WILL HAVE SLIGHTLY BETTER
MOISTURE PROFILES.

WEDNESDAY NIGHT SHOWERS SHOULD DIMINISH WITH THE LOSS OF DAYTIME
HEATING AND THE INCREASING STABILITY OF THE ATMOSPHERE.

TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL FOR DAYTIME
HIGHS THIS PERIOD...WHILE OVER NIGHT LOWS WILL AVERAGE A FEW DEGREES
BELOW NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE FEATURE OF NOTE TO START THIS TIME PERIOD IS PRESENTLY FOUND
OVER THE STATE OF NEVADA AS A SHORTWAVE SLOWLY RIDES NORTHWARD
ALONG THE WESTERN FLANK OF A LONG RANGE RIDGE. TIMING THIS FEATURE
OVER THE ROCKIES...AND NORTHERN PLAIN STATES WILL BRING THE NEXT
WIDESPREAD THREAT OF SHOWERS AND THUNDERSTORMS INTO THE REGION
FRIDAY. THERE MAY BE A FEW STORMS THURSDAY AHEAD OF THIS FEATURE
NEAR THE STATE LINE...BUT BOTH THE 12Z GFS AND 12Z ECMWF SUGGEST
THAT FRIDAY WILL BE THE BEST DAY FOR PRECIPITATION CHANCES. WILL
MAINTAIN LOW CHANCE POPS FRIDAY AS THE MODELS CONTINUE A HIGH
DEGREE OF UNCERTAINTY TO THIS SHORTWAVE TRACK...POSSIBLY TRACKING
FARTHER SOUTHWARD WHICH WOULD LEAVE FRIDAY DRY...ESPECIALLY OUR
NORTHERN ZONES.

THIS SHORTWAVE MAY DRAW THE UPPER LEVEL LOW OVER EASTERN CANADA BACK
SOUTHWARD...LEAVING CHANCES FOR SHOWERS AND THUNDERSTORMS ON
SATURDAY ACROSS WESTERN AND NORTH CENTRAL NEW YORK STATE. THESE
SHOWERS AND THUNDERSTORMS MAY LINGER INTO SUNDAY DEPENDING UPON HOW
QUICKLY THE LOWER HEIGHTS ASSOCIATED WITH THE QUEBEC LOW LINGER OVER
THE EASTERN GREAT LAKES REGION.

WITH THE UPPER LEVEL LOW OVER QUEBEC NEARBY...TEMPERATURES ARE
EXPECTED TO REMAIN JUST BELOW SEASONAL NORMALS THROUGH THIS TIME
PERIOD.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL KEEP
FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR THIS
WILL COME OVER THE HILLS OF THE SOUTHERN TIER TO THE FINGER LAKES
REGION WHERE THE STRONGER WINDS ALOFT WILL HAVE A LOWER CHANCE OF
MIXING TO THE SFC.

THUNDERSTORMS WILL ACCOMPANY THE COLD FRONTAL PASSAGE ON MONDAY.
THERE MAY BE LOWER MVFR TO IFR CONDITIONS WITH THE STORMS...AS WELL
AS THE RISK OF SEVERE CATEGORY WIND GUSTS...BUT MOST OF THE TIME
WILL BE VFR.

OUTLOOK...

SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.
FRIDAY...CHANCE OF THUNDERSTORMS OVER THE SOUTHERN TIER...OTHERWISE VFR.

&&

.MARINE...
SOUTHWEST WINDS SUSTAINED 10 TO 15 KNOTS WITH GUSTS TO 20 KNOTS WILL
INCREASE ENOUGH TO 15 TO 20 KNOT GUSTING 25 KNOTS THIS AFTERNOON...
SUFFICIENT FOR SMALL CRAFT ADVISORIES ON LAKE ERIE...NIAGARA RIVER
AND WESTERN LAKE ONTARIO.

CONDITIONS WILL FURTHER DETERIORATE TONIGHT AS A STRONG COLD FRONT
WILL TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES AND THE
SURFACE PRESSURE GRADIENT INCREASES. WINDS WILL INCREASE TO NEAR 30
KNOTS ON LAKE ERIE AND PARTS OF WESTERN LAKE ONTARIO LATER
TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING AS WELL. WAVES
ON NORTHEASTERN LAKE ERIE WILL LIKELY REACH 6 FEET AT TIMES BY
DAYBREAK...WITH WIDESPREAD COVERAGE OF WAVES AVERAGING MORE THAN 4
FEET BY 06Z.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES MONDAY
MORNING...WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE. THE SEVERE
THREAT FROM THESE STORMS WILL BE WIND GUSTS NEARING OR EXCEEDING 50
KNOTS. ALONG WITH THE THREAT OF CONVECTION...SMALL CRAFT ADVISORIES
WILL BE IN EFFECT ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE
DAY. WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY
AND MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT MONDAY NIGHT FOR
         LOZ042.

&&

$$

SYNOPSIS...WCH
NEAR TERM...WCH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...WCH
MARINE...WCH




000
FXUS61 KBUF 021445
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1045 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HAVE UPDATED THE FORECAST TO ACCENTUATE THE GUSTY SOUTHWEST WINDS ON
THE LAKESHORES AND NIAGARA RIVER...WITH SMALL CRAFT ADVISORIES IN
EFFECT THIS AFTERNOON THROUGH TONIGHT AND MONDAY AFTERNOON.

HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS AND STORMS PRESSING/DEVELOPING SOUTHEASTWARD ACROSS THE
AREA OVER TIME. WHILE THIS IS NOT COMPLETELY IN LINE WITH THE
THINKING OUTLINED ABOVE...THIS DOES REPRESENT A REASONABLE FIRST
STEP IN TRENDING THE FORECAST IN THAT DIRECTION...AND AT THE SAME
TIME LEAVES ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST
THINGS FURTHER /IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...PLENTY ENOUGH DEEP-LAYER SHEAR (0-6 KM BULK SHEAR
VALUES OF 35-50 KNOTS) STILL LOOKS TO BE PRESENT TO WARRANT AT
LEAST A CHANCE FOR SOME STRONGER TO SEVERE STORMS...WITH THE
PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING THAT DAMAGING WINDS
WOULD BE THE PRIMARY SEVERE WEATHER THREAT. THE LATEST SPC DAY 2
OUTLOOK IS IN AGREEMENT WITH THIS THINKING...AND SUGGESTS A
MARGINAL RISK FOR SEVERE STORMS FROM THE GENESEE VALLEY EASTWARD
AND A SLIGHT RISK FROM OUR SOUTHEASTERN PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR
THIS WILL COME OVER THE FINGER LAKES REGION WHERE THE STRONGER
WINDS ALOFT WILL HAVE A LOWER CHANCE OF MIXING TO THE SFC.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
SOUTHWEST WINDS SUSTAINED 10 TO 15 KNOTS WITH GUSTS TO 20 KNOTS WILL
INCREASE ENOUGH TO 15 TO 20 KNOT GUSTING 25 KNOTS THIS AFTERNOON...
SUFFICIENT FOR SMALL CRAFT ADVISORIES ON LAKE ERIE...NIAGARA RIVER
AND WESTERN LAKE ONTARIO.

CONDITIONS WILL FURTHER DETERIORATE TONIGHT AS A STRONG COLD FRONT
WILL TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE ONTARIO
LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING AS WELL.
WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END SMALL
CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO... BUT
WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY TODAYS FINE
WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT
         EDT MONDAY NIGHT FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM
         EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ043>045.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ042.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH/WCH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH/WCH





000
FXUS61 KBUF 021445
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1045 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HAVE UPDATED THE FORECAST TO ACCENTUATE THE GUSTY SOUTHWEST WINDS ON
THE LAKESHORES AND NIAGARA RIVER...WITH SMALL CRAFT ADVISORIES IN
EFFECT THIS AFTERNOON THROUGH TONIGHT AND MONDAY AFTERNOON.

HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS AND STORMS PRESSING/DEVELOPING SOUTHEASTWARD ACROSS THE
AREA OVER TIME. WHILE THIS IS NOT COMPLETELY IN LINE WITH THE
THINKING OUTLINED ABOVE...THIS DOES REPRESENT A REASONABLE FIRST
STEP IN TRENDING THE FORECAST IN THAT DIRECTION...AND AT THE SAME
TIME LEAVES ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST
THINGS FURTHER /IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...PLENTY ENOUGH DEEP-LAYER SHEAR (0-6 KM BULK SHEAR
VALUES OF 35-50 KNOTS) STILL LOOKS TO BE PRESENT TO WARRANT AT
LEAST A CHANCE FOR SOME STRONGER TO SEVERE STORMS...WITH THE
PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING THAT DAMAGING WINDS
WOULD BE THE PRIMARY SEVERE WEATHER THREAT. THE LATEST SPC DAY 2
OUTLOOK IS IN AGREEMENT WITH THIS THINKING...AND SUGGESTS A
MARGINAL RISK FOR SEVERE STORMS FROM THE GENESEE VALLEY EASTWARD
AND A SLIGHT RISK FROM OUR SOUTHEASTERN PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR
THIS WILL COME OVER THE FINGER LAKES REGION WHERE THE STRONGER
WINDS ALOFT WILL HAVE A LOWER CHANCE OF MIXING TO THE SFC.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
SOUTHWEST WINDS SUSTAINED 10 TO 15 KNOTS WITH GUSTS TO 20 KNOTS WILL
INCREASE ENOUGH TO 15 TO 20 KNOT GUSTING 25 KNOTS THIS AFTERNOON...
SUFFICIENT FOR SMALL CRAFT ADVISORIES ON LAKE ERIE...NIAGARA RIVER
AND WESTERN LAKE ONTARIO.

CONDITIONS WILL FURTHER DETERIORATE TONIGHT AS A STRONG COLD FRONT
WILL TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE ONTARIO
LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING AS WELL.
WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END SMALL
CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO... BUT
WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY TODAYS FINE
WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         MONDAY FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT
         EDT MONDAY NIGHT FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM
         EDT MONDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ043>045.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT
         EDT MONDAY NIGHT FOR LOZ042.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH/WCH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH/WCH




000
FXUS61 KBUF 021138
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
738 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS AND STORMS PRESSING/DEVELOPING SOUTHEASTWARD ACROSS THE
AREA OVER TIME. WHILE THIS IS NOT COMPLETELY IN LINE WITH THE
THINKING OUTLINED ABOVE...THIS DOES REPRESENT A REASONABLE FIRST
STEP IN TRENDING THE FORECAST IN THAT DIRECTION...AND AT THE SAME
TIME LEAVES ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST
THINGS FURTHER /IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...PLENTY ENOUGH DEEP-LAYER SHEAR (0-6 KM BULK SHEAR
VALUES OF 35-50 KNOTS) STILL LOOKS TO BE PRESENT TO WARRANT AT
LEAST A CHANCE FOR SOME STRONGER TO SEVERE STORMS...WITH THE
PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING THAT DAMAGING WINDS
WOULD BE THE PRIMARY SEVERE WEATHER THREAT. THE LATEST SPC DAY 2
OUTLOOK IS IN AGREEMENT WITH THIS THINKING...AND SUGGESTS A
MARGINAL RISK FOR SEVERE STORMS FROM THE GENESEE VALLEY EASTWARD
AND A SLIGHT RISK FROM OUR SOUTHEASTERN PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR
THIS WILL COME OVER THE FINGER LAKES REGION WHERE THE STRONGER
WINDS ALOFT WILL HAVE A LOWER CHANCE OF MIXING TO THE SFC.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL NOSE NORTH
ACROSS THE LOWER GREAT LAKES TODAY. THIS WILL RESULT IN A WEAKER
SFC PRESSURE GRADIENT THAN RECENT DAYS...SO WHILE GENTLE WINDS
WILL FRESHEN TO A MODERATE BREEZE DURING THE COURSE OF THE MORNING
AND MIDDAY...CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.

CONDITIONS WILL DETERIORATE TONIGHT AS A STRONG COLD FRONT WILL
TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE
ONTARIO LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING
AS WELL. WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END
SMALL CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO...
BUT WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY
TODAYS FINE WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH




000
FXUS61 KBUF 021138
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
738 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS AND STORMS PRESSING/DEVELOPING SOUTHEASTWARD ACROSS THE
AREA OVER TIME. WHILE THIS IS NOT COMPLETELY IN LINE WITH THE
THINKING OUTLINED ABOVE...THIS DOES REPRESENT A REASONABLE FIRST
STEP IN TRENDING THE FORECAST IN THAT DIRECTION...AND AT THE SAME
TIME LEAVES ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST
THINGS FURTHER /IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...PLENTY ENOUGH DEEP-LAYER SHEAR (0-6 KM BULK SHEAR
VALUES OF 35-50 KNOTS) STILL LOOKS TO BE PRESENT TO WARRANT AT
LEAST A CHANCE FOR SOME STRONGER TO SEVERE STORMS...WITH THE
PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING THAT DAMAGING WINDS
WOULD BE THE PRIMARY SEVERE WEATHER THREAT. THE LATEST SPC DAY 2
OUTLOOK IS IN AGREEMENT WITH THIS THINKING...AND SUGGESTS A
MARGINAL RISK FOR SEVERE STORMS FROM THE GENESEE VALLEY EASTWARD
AND A SLIGHT RISK FROM OUR SOUTHEASTERN PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR. THE HIGHEST CHANCE FOR
THIS WILL COME OVER THE FINGER LAKES REGION WHERE THE STRONGER
WINDS ALOFT WILL HAVE A LOWER CHANCE OF MIXING TO THE SFC.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL NOSE NORTH
ACROSS THE LOWER GREAT LAKES TODAY. THIS WILL RESULT IN A WEAKER
SFC PRESSURE GRADIENT THAN RECENT DAYS...SO WHILE GENTLE WINDS
WILL FRESHEN TO A MODERATE BREEZE DURING THE COURSE OF THE MORNING
AND MIDDAY...CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.

CONDITIONS WILL DETERIORATE TONIGHT AS A STRONG COLD FRONT WILL
TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE
ONTARIO LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING
AS WELL. WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END
SMALL CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO...
BUT WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY
TODAYS FINE WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 020920
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
520 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS AND STORMS PRESSING/DEVELOPING SOUTHEASTWARD ACROSS THE
AREA OVER TIME. WHILE THIS IS NOT COMPLETELY IN LINE WITH THE
THINKING OUTLINED ABOVE...THIS DOES REPRESENT A REASONABLE FIRST
STEP IN TRENDING THE FORECAST IN THAT DIRECTION...AND AT THE SAME
TIME LEAVES ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST
THINGS FURTHER /IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...PLENTY ENOUGH DEEP-LAYER SHEAR (0-6 KM BULK SHEAR
VALUES OF 35-50 KNOTS) STILL LOOKS TO BE PRESENT TO WARRANT AT
LEAST A CHANCE FOR SOME STRONGER TO SEVERE STORMS...WITH THE
PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING THAT DAMAGING WINDS
WOULD BE THE PRIMARY SEVERE WEATHER THREAT. THE LATEST SPC DAY 2
OUTLOOK IS IN AGREEMENT WITH THIS THINKING...AND SUGGESTS A
MARGINAL RISK FOR SEVERE STORMS FROM THE GENESEE VALLEY EASTWARD
AND A SLIGHT RISK FROM OUR SOUTHEASTERN PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL NOSE NORTH
ACROSS THE LOWER GREAT LAKES TODAY. THIS WILL RESULT IN A WEAKER
SFC PRESSURE GRADIENT THAN RECENT DAYS...SO WHILE GENTLE WINDS
WILL FRESHEN TO A MODERATE BREEZE DURING THE COURSE OF THE MORNING
AND MIDDAY...CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.

CONDITIONS WILL DETERIORATE TONIGHT AS A STRONG COLD FRONT WILL
TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE
ONTARIO LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING
AS WELL. WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END
SMALL CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO...
BUT WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY
TODAYS FINE WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 020816
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
416 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS/STORMS PRESSING SOUTHEASTWARD ACROSS THE AREA OVER TIME.
WHILE THIS IS NOT COMPLETELY IN LINE WITH THE THINKING OUTLINED
ABOVE...THIS DOES REPRESENT A REASONABLE FIRST STEP IN TRENDING
THE FORECAST IN THAT DIRECTION...AND AT THE SAME TIME LEAVES
ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST THINGS FURTHER
/IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...ENOUGH DEEP LAYER-SHEAR STILL LOOKS TO BE PRESENT TO
WARRANT AT LEAST A CHANCE FOR SOME STRONGER TO SEVERE
STORMS...WITH THE PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING
THAT DAMAGING WINDS WOULD BE THE PRIMARY SEVERE WEATHER THREAT.
THE LATEST SPC DAY 2 OUTLOOK IS IN AGREEMENT WITH THIS
THINKING...AND SUGGESTS A MARGINAL RISK FOR SEVERE STORMS FROM THE
GENESEE VALLEY EASTWARD AND A SLIGHT RISK FROM OUR SOUTHEASTERN
PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL NOSE NORTH
ACROSS THE LOWER GREAT LAKES TODAY. THIS WILL RESULT IN A WEAKER
SFC PRESSURE GRADIENT THAN RECENT DAYS...SO WHILE GENTLE WINDS
WILL FRESHEN TO A MODERATE BREEZE DURING THE COURSE OF THE MORNING
AND MIDDAY...CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.

CONDITIONS WILL DETERIORATE TONIGHT AS A STRONG COLD FRONT WILL
TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE
ONTARIO LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING
AS WELL. WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END
SMALL CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO...
BUT WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY
TODAYS FINE WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH




000
FXUS61 KBUF 020816
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
416 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR SOUTH WILL GUARANTEE A NICE SUMMER
DAY ACROSS OUR REGION TODAY...WITH TEMPERATURES CLIMBING WELL INTO
THE 80S. A STRONG COLD FRONT WILL BRING AN END TO OUR FAIR WEATHER
LATER TONIGHT AND MONDAY...WITH STRONG TO SEVERE STORMS POSSIBLE
EAST OF THE GENESEE VALLEY MONDAY AFTERNOON. A COMFORTABLY COOL
AIRMASS WILL FOLLOW THE FRONT MONDAY NIGHT AND SHOULD BE IN PLACE
FOR AT LEAST THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE NOSING NORTH FROM THE UPPER OHIO VALLEY WILL
PRODUCE A FINE SUMMER DAY ACROSS OUR REGION TODAY. IT WILL BE
NOTABLY WARMER THAN SATURDAY...AS THE CLOCKWISE CIRCULATION AROUND
THE FAIR WEATHER SYSTEM WILL PUMP H85 TEMPS TO BETWEEN 16 AND 18C.
THIS WILL EASILY SUPPORT AFTERNOON HIGHS IN THE MID 80S ACROSS THE
LAKE PLAINS AND SRN TIER VALLEYS...WITH SOME SPOTS IN THE GENESEE
VALLEY AND FINGER LAKES POSSIBLY REACHING THE UPPER 80S. THE
WARMTH WILL BE ACCOMPANIED BY A STEADY BREEZE AND RELATIVELY LOW
DEW POINTS THOUGH (MID-UP 50S)...SO CONDITIONS SHOULD BE NICE FOR
OUTDOOR ACTIVITIES.

OUR WEATHER WILL THEN DETERIORATE TONIGHT AS A STRONG COLD FRONT
FROM THE UPPER GREAT LAKES WILL TAKE AIM ON OUR REGION. THE
FRONT... OVER LAKE SUPERIOR THIS MORNING...WILL SETTLE ACROSS THE
UPPER GREAT LAKES THIS AFTERNOON AND EVENING BEFORE PUSHING ITS
WAY ACROSS SOUTHERN ONTARIO DURING THE PRE DAWN HOURS. WHILE SOME
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT COULD ARRIVE LATE
TONIGHT FOR AREAS CLOSE TO LAKES ERIE AND ONTARIO...THE BULK OF
THE PCPN SHOULD HOLD OFF UNTIL DAYBREAK. OTHERWISE IT WILL BE A
BREEZY AND WARM NIGHT... WITH A STRENGTHENING SOUTHERLY FLOW
PREVENTING TEMPERATURES IN MOST AREAS FROM FALLING BELOW THE UPPER
60S. WINDS ACROSS THE HIGHER ELEVATIONS OF THE SRN TIER AND CLOSE
TO LAKE ERIE COULD GUST TO 35 MPH.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ON MONDAY UPPER LEVEL TROUGHING WILL CONTINUE TO DIG
SOUTHEASTWARD ACROSS THE GREAT LAKES REGION. MEANWHILE AT THE
SURFACE...AN ATTENDANT MODEST SURFACE REFLECTION WILL BODILY LIFT
NORTHEASTWARD OVER QUEBEC PROVINCE...WHILE SLOWLY PUSHING ITS
TRAILING COLD FRONT SOUTHEASTWARD ACROSS OUR AREA. OVER THE PAST
24 HOURS...THE OPERATIONAL GUIDANCE SUITE HAS UNIVERSALLY SLOWED
DOWN THE TIMING OF THE FRONTAL PASSAGE... WITH MOST OF THE
GUIDANCE PACKAGES NOW SUGGESTING THAT THE BOUNDARY WILL PASS
THROUGH OUR REGION BETWEEN MID MONDAY AFTERNOON AND EARLY MONDAY
EVENING...WITH THE NAM A SOMEWHAT SLOWER OUTLIER COMPARED TO THE
GLOBAL MODEL CONSENSUS.

WHILE THE GUIDANCE HAS THUS COME INTO BETTER AGREEMENT ON A LATER
TIMING OF THE COLD FRONT...SOME NOTEWORTHY DISAGREEMENT REMAINS ON
THE EXTENT/EVOLUTION OF CONVECTION ALONG AND AHEAD OF THIS
BOUNDARY DURING THE COURSE OF MONDAY. MORE SPECIFICALLY...THE
ECMWF/GEM BOTH MORE OR LESS SEEM TO SUGGEST THAT A PREFRONTAL
SWATH OF CONVECTION WILL WORK INTO THE AREA MONDAY MORNING AND
THEN DEVELOP FURTHER/ BECOME BETTER ORGANIZED AS IT PRESSES
SOUTHEASTWARD DURING THE AFTERNOON AS THE COLD FRONT CROSSES OUR
REGION DURING PEAK DIURNAL HEATING. IN CONTRAST...THE GFS AND
ESPECIALLY THE NAM HINT AT ANY INITIAL MORNING CONVECTION BEING
MUCH MORE SCATTERED IN COVERAGE AND POTENTIALLY EVEN SPLITTING OUR
AREA TO THE NORTH AND SOUTH...RESULTING IN A GENERALLY DRY MORNING
FOLLOWED BY ADDITIONAL CONVECTION DEVELOPING TO THE LEE OF THE
LAKES MONDAY AFTERNOON AS THE COLD FRONT BEGINS PUSHING INTO THE
AREA...A SCENARIO THAT IS ALSO SUGGESTED BY THE HIRESW NMM/ARW.

GIVEN THAT A FAIRLY BRISK SOUTHWESTERLY FLOW WILL ALREADY BE IN
PLACE ACROSS OUR REGION MONDAY MORNING...SUSPECT THAT THE LATTER
BUNCH OF GUIDANCE MAY INDEED BE ON TO SOMETHING...AS SUCH A
SCENARIO TENDS TO BE FAIRLY COMMONPLACE FOR OUR AREA WITH
AFTERNOON COLD FRONTAL PASSAGES DURING THE SUMMER MONTHS. CAN
EASILY FORESEE A SCENARIO WHERE ONLY VERY LIMITED/DISORGANIZED
CONVECTION ENTERS OUR AREA MONDAY MORNING AND POTENTIALLY FALLS
APART AS IT ENCOUNTERS THE INCREASINGLY STABILIZING INFLUENCES OF
THE LAKES...WITH A SECOND ROUND OF MORE NUMEROUS AND BETTER
ORGANIZED SHOWERS/STORMS THEN INITIATING ON LAKE BREEZE BOUNDARIES
AND SWEEPING EASTWARD ACROSS THE AREA MONDAY AFTERNOON.

THIS PRESENTS A BIT OF A FORECAST QUANDARY AS TO HOW TO HANDLE
THE POP FORECAST ON MONDAY...AS OUR PREVIOUS CONTINUITY PRETTY
MUCH BROUGHT A SOLID SWATH OF CATEGORICAL POPS INTO THE AREA
DURING THE MORNING...THEN WORKED THIS SOUTHEASTWARD ACROSS THE
REST OF THE AREA MONDAY AFTERNOON. GIVEN BOTH THIS AND THE
INCREASING AMOUNT OF UNCERTAINTY WITH RESPECT TO THE EXTENT/
ORGANIZATION OF ANY MORNING CONVECTION...AS AN INITIAL STEP HAVE
ELECTED TO CUT POPS BACK TO THE LOWER END OF THE LIKELY RANGE FOR
MONDAY...WHILE STILL MAINTAINING THE GENERAL IDEA OF A REGION OF
SHOWERS/STORMS PRESSING SOUTHEASTWARD ACROSS THE AREA OVER TIME.
WHILE THIS IS NOT COMPLETELY IN LINE WITH THE THINKING OUTLINED
ABOVE...THIS DOES REPRESENT A REASONABLE FIRST STEP IN TRENDING
THE FORECAST IN THAT DIRECTION...AND AT THE SAME TIME LEAVES
ENOUGH WIGGLE ROOM FOR SUBSEQUENT SHIFTS TO ADJUST THINGS FURTHER
/IN EITHER DIRECTION/ AS ULTIMATELY REQUIRED.

WITH RESPECT TO SEVERE POTENTIAL ON MONDAY...THE OPERATIONAL
GUIDANCE SUITE SUGGESTS THAT MODEST TO MODERATE LEVELS OF
INSTABILITY (SBCAPES OF 500-1500 J/KG...WITH LOCALLY HIGHER
POCKETS OF UP TO 2000 J/KG) WILL DEVELOP OUT AHEAD OF THE
APPROACHING COLD FRONT MONDAY AFTERNOON. IF SUCH INSTABILITY IS
REALIZED...ENOUGH DEEP LAYER-SHEAR STILL LOOKS TO BE PRESENT TO
WARRANT AT LEAST A CHANCE FOR SOME STRONGER TO SEVERE
STORMS...WITH THE PRIMARILY UNIDIRECTIONAL FLOW REGIME DICTATING
THAT DAMAGING WINDS WOULD BE THE PRIMARY SEVERE WEATHER THREAT.
THE LATEST SPC DAY 2 OUTLOOK IS IN AGREEMENT WITH THIS
THINKING...AND SUGGESTS A MARGINAL RISK FOR SEVERE STORMS FROM THE
GENESEE VALLEY EASTWARD AND A SLIGHT RISK FROM OUR SOUTHEASTERN
PERIPHERY EASTWARD.

OTHERWISE...EXPECT ONE MORE DAY OF SEASONABLE TO SLIGHTLY ABOVE
NORMAL TEMPERATURES ON MONDAY...WITH 850 MB TEMPS IN THE MID TEENS
SUPPORTING HIGHS MOSTLY IN THE UPPER 70S TO MID 80S...AND EXPECTED
CLOUD COVER/ CONVECTION/LAKE INFLUENCES HOLDING THESE READINGS
DOWN A BIT FROM WHAT THEY OTHERWISE WOULD BE ON A FAIR WEATHER
DAY.

MONDAY NIGHT...ANY LINGERING CONVECTION ASSOCIATED WITH THE FRONT
SHOULD DEPART OUR AREA TO THE SOUTHEAST DURING THE EVENING AS THIS
BOUNDARY CLEARS OUR REGION...WITH A SWATH OF RELATIVELY DRIER AIR
AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRY AND QUIET
CONDITIONS FOR THE BALANCE OF THE NIGHT. WITH SLOW BUT STEADY COOL
AIR ADVECTION ALSO IN PLACE...OVERNIGHT LOWS WILL DROP BACK SOME
FROM THE READINGS OF THE PREVIOUS NIGHT...WITH MOST LOCATIONS
SEEING OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S.

DURING THE REMAINDER OF THE PERIOD...THE AXIS OF THE
AFOREMENTIONED UPPER LEVEL TROUGH WILL THEN CONTINUE TO PRESS
EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW ENGLAND. IN
ASSOCIATION WITH THIS...A SECONDARY COLD FRONT WILL SWING ACROSS
THE REGION ON TUESDAY AND BRING ANOTHER ROUND OF SCATTERED SHOWERS
AND THUNDERSTORMS...WITH LINGERING SYNOPTIC-SCALE SHOWERS /AND
SOME LAKE ENHANCED SHOWERS DOWNWIND OF LAKE ONTARIO/ THEN
DIMINISHING FROM WEST TO EAST TUESDAY NIGHT AND WEDNESDAY AS
SURFACE-BASED RIDGING AND DRIER AIR SETTLES ACROSS OUR REGION.
WITH OUR REGION FIRMLY WITHIN THE GRIP OF THE UPPER LEVEL
TROUGH...A GENERAL WESTERLY FLOW OF PROGRESSIVELY COOLER AIR WILL
ALSO CONTINUE ACROSS OUR REGION...WITH THIS ESPECIALLY THE CASE IN
THE WAKE OF THE SECONDARY COLD FRONT TUESDAY NIGHT AND WEDNESDAY.
THIS WILL RESULT IN TEMPERATURES TRENDING TO SOLIDLY BELOW NORMAL
/BUT ALSO VERY COMFORTABLE/ LEVELS BY MIDWEEK...WITH DAYTIME HIGHS
FALLING MAINLY INTO THE LOWER 70S BY WEDNESDAY...AND NIGHTTIME
LOWS SETTLING INTO THE 50S AREAWIDE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PORTION OF THE FORECAST STILL LOOKS TO FEATURE BROAD
BUT PERSISTENT UPPER LEVEL TROUGHING ACROSS EASTERN NORTH
AMERICA...WHILE SURFACE-BASED RIDGING INITIALLY OVER OUR REGION
WEDNESDAY NIGHT AND THURSDAY GRADUALLY GIVES WAY TO A WAVE OF LOW
PRESSURE PASSING ACROSS THE OHIO VALLEY AND MID ATLANTIC STATES BY
NEXT WEEKEND.

FOR OUR REGION...THIS PATTERN WILL RESULT IN CONTINUED BELOW
NORMAL BUT ALSO PLEASANT TEMPERATURES WITH DAILY HIGHS IN THE
LOWER TO MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE
50S...WHILE GENERALLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY
EVENTUALLY GIVES WAY TO RENEWED CHANCES FOR SOME SHOWERS AND
THUNDERSTORMS BY NEXT WEEKEND.

&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE UPPER OHIO VALLEY WILL
KEEP FAIR VFR CONDITIONS IN PLACE THROUGH AT LEAST THIS EVENING.

A STRONG COLD FRONT OVER THE UPPER GREAT LAKES WILL THEN APPROACH
OUR REGION DURING THE OVERNIGHT HOURS. WHILE VFR CONDITIONS WILL
REMAIN IN PLACE FOR MUCH OF THE NIGHT...SHOWERS AND THUNDERSTORMS
AHEAD OF THE FRONT COULD IMPACT THE REGION AFTER MIDNIGHT.

ALONG WITH THE THREAT FOR LATE NIGHT THUNDERSTORMS...A 40 TO 50
KNOT LOW LEVEL JET AHEAD OF THE FRONT COULD PRODUCE CONDITIONS
FAVORABLE FOR SOME LOW LEVEL WIND SHEAR.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND THUNDERSTORMS AND
ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER 06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL NOSE NORTH
ACROSS THE LOWER GREAT LAKES TODAY. THIS WILL RESULT IN A WEAKER
SFC PRESSURE GRADIENT THAN RECENT DAYS...SO WHILE GENTLE WINDS
WILL FRESHEN TO A MODERATE BREEZE DURING THE COURSE OF THE MORNING
AND MIDDAY...CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.

CONDITIONS WILL DETERIORATE TONIGHT AS A STRONG COLD FRONT WILL
TAKE AIM ON OUR REGION FROM THE UPPER GREAT LAKES. WINDS WILL
FRESHEN TO NEAR 30 KNOTS ON LAKE ERIE AND PARTS OF WRN LAKE
ONTARIO LATER TONIGHT...WITH THE RISK FOR THUNDERSTORMS INCREASING
AS WELL. WAVES ON LK ERIE WILL LIKELY EXCEED 6 FEET AT TIMES BY
DAYBREAK...WITH PROBLEMATIC WAVES POSSIBLE BY 06Z. A HIGH END
SMALL CRAFT ADVISORY WILL CERTAINLY BE NEEDED FOR THIS SCENARIO...
BUT WILL ALLOW RECREATIONAL BOATERS THE OPPORTUNITY TO ENJOY
TODAYS FINE WEATHER BEFORE ISSUING A SCA LATER TODAY.

THE COLD FRONT WILL MAKE ITS WAY ACROSS THE LOWER GREAT LAKES
MONDAY MORNING...WITH STRONG THUNDERSTORMS POSSIBLE. THE HIGHEST
RISK FOR THESE STORMS WILL BE FOUND OVER THE EASTERN HALF OF LAKE
ONTARIO. ALONG WITH THE THREAT OF CONVECTION...SCA`S WILL LIKELY
BE IN PLACE ACROSS THE LOWER GREAT LAKES FOR THE BULK OF THE DAY.
WINDS WILL TEMPORARILY SUBSIDE ACROSS THE REGION LATE MONDAY AND
MONDAY NIGHT.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 020552
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
152 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL PRODUCE A
MOONLIT SKY ACROSS THE BULK OF THE FORECAST AREA OVERNIGHT...WITH
SOME PATCHES OF ALTO-CUMULUS CLOUDS EXPECTED TO CROSS THE NORTH
COUNTRY. IT WILL BE COMFORTABLE FOR SLEEPING AS TEMPERATURES WILL
SETTLE INTO THE 50S AWAY FROM THE LAKES.

ON SUNDAY...HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL KEEP FAIR
VFR CONDITIONS IN PLACE FOR THE REMAINDER OF THE OVERNIGHT WITH
LIGHT WINDS.

AFTER DAYBREAK...HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO
VALLEY TO THE MID ATLANTIC. THIS WILL PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE EARLY SUNDAY NIGHT WITH AN
APPROACHING COLD FRONT.

WHILE SOME GUIDANCE PACKAGES ARE SUGGESTING THAT A 40KT LOW LEVEL JET
WILL BE IN PLACE BY 06Z...WILL KEEP OUT OF THE TAFS FOR NOW AS AT
LEAST A PORTION OF THESE WINDS MAY MIX TO THE SFC.

OUTLOOK... SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER
06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY HAS LESSENED
THE SFC PRESSURE GRADIENT OVER THE LOWER GREAT LAKES...SO GENTLE
TO LIGHT WINDS CAN BE EXPECTED THROUGH DAYBREAK.

WHILE WINDS WILL FRESHEN AS WE PROGRESS THROUGH SUNDAY MORNING...
CONDITIONS ARE LIKELY TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE LOWER GREAT LAKES LATE SUNDAY
NIGHT AND MONDAY AND LIKELY BRING A ROUND OF SMALL CRAFT ADVISORY
CONDITIONS TO LAKES ERIE AND ONTARIO...ALONG WITH THE LIKELIHOOD
OF STRONG TO POTENTIALLY SEVERE THUNDERSTORMS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/RSH
MARINE...RSH




000
FXUS61 KBUF 020552
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
152 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL PRODUCE A
MOONLIT SKY ACROSS THE BULK OF THE FORECAST AREA OVERNIGHT...WITH
SOME PATCHES OF ALTO-CUMULUS CLOUDS EXPECTED TO CROSS THE NORTH
COUNTRY. IT WILL BE COMFORTABLE FOR SLEEPING AS TEMPERATURES WILL
SETTLE INTO THE 50S AWAY FROM THE LAKES.

ON SUNDAY...HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL KEEP FAIR
VFR CONDITIONS IN PLACE FOR THE REMAINDER OF THE OVERNIGHT WITH
LIGHT WINDS.

AFTER DAYBREAK...HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO
VALLEY TO THE MID ATLANTIC. THIS WILL PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE EARLY SUNDAY NIGHT WITH AN
APPROACHING COLD FRONT.

WHILE SOME GUIDANCE PACKAGES ARE SUGGESTING THAT A 40KT LOW LEVEL JET
WILL BE IN PLACE BY 06Z...WILL KEEP OUT OF THE TAFS FOR NOW AS AT
LEAST A PORTION OF THESE WINDS MAY MIX TO THE SFC.

OUTLOOK... SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER
06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY HAS LESSENED
THE SFC PRESSURE GRADIENT OVER THE LOWER GREAT LAKES...SO GENTLE
TO LIGHT WINDS CAN BE EXPECTED THROUGH DAYBREAK.

WHILE WINDS WILL FRESHEN AS WE PROGRESS THROUGH SUNDAY MORNING...
CONDITIONS ARE LIKELY TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE LOWER GREAT LAKES LATE SUNDAY
NIGHT AND MONDAY AND LIKELY BRING A ROUND OF SMALL CRAFT ADVISORY
CONDITIONS TO LAKES ERIE AND ONTARIO...ALONG WITH THE LIKELIHOOD
OF STRONG TO POTENTIALLY SEVERE THUNDERSTORMS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/RSH
MARINE...RSH





000
FXUS61 KBUF 020552
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
152 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL PRODUCE A
MOONLIT SKY ACROSS THE BULK OF THE FORECAST AREA OVERNIGHT...WITH
SOME PATCHES OF ALTO-CUMULUS CLOUDS EXPECTED TO CROSS THE NORTH
COUNTRY. IT WILL BE COMFORTABLE FOR SLEEPING AS TEMPERATURES WILL
SETTLE INTO THE 50S AWAY FROM THE LAKES.

ON SUNDAY...HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL KEEP FAIR
VFR CONDITIONS IN PLACE FOR THE REMAINDER OF THE OVERNIGHT WITH
LIGHT WINDS.

AFTER DAYBREAK...HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO
VALLEY TO THE MID ATLANTIC. THIS WILL PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE EARLY SUNDAY NIGHT WITH AN
APPROACHING COLD FRONT.

WHILE SOME GUIDANCE PACKAGES ARE SUGGESTING THAT A 40KT LOW LEVEL JET
WILL BE IN PLACE BY 06Z...WILL KEEP OUT OF THE TAFS FOR NOW AS AT
LEAST A PORTION OF THESE WINDS MAY MIX TO THE SFC.

OUTLOOK... SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER
06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY HAS LESSENED
THE SFC PRESSURE GRADIENT OVER THE LOWER GREAT LAKES...SO GENTLE
TO LIGHT WINDS CAN BE EXPECTED THROUGH DAYBREAK.

WHILE WINDS WILL FRESHEN AS WE PROGRESS THROUGH SUNDAY MORNING...
CONDITIONS ARE LIKELY TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE LOWER GREAT LAKES LATE SUNDAY
NIGHT AND MONDAY AND LIKELY BRING A ROUND OF SMALL CRAFT ADVISORY
CONDITIONS TO LAKES ERIE AND ONTARIO...ALONG WITH THE LIKELIHOOD
OF STRONG TO POTENTIALLY SEVERE THUNDERSTORMS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/RSH
MARINE...RSH




000
FXUS61 KBUF 020552
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
152 AM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL PRODUCE A
MOONLIT SKY ACROSS THE BULK OF THE FORECAST AREA OVERNIGHT...WITH
SOME PATCHES OF ALTO-CUMULUS CLOUDS EXPECTED TO CROSS THE NORTH
COUNTRY. IT WILL BE COMFORTABLE FOR SLEEPING AS TEMPERATURES WILL
SETTLE INTO THE 50S AWAY FROM THE LAKES.

ON SUNDAY...HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY WILL KEEP FAIR
VFR CONDITIONS IN PLACE FOR THE REMAINDER OF THE OVERNIGHT WITH
LIGHT WINDS.

AFTER DAYBREAK...HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO
VALLEY TO THE MID ATLANTIC. THIS WILL PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE EARLY SUNDAY NIGHT WITH AN
APPROACHING COLD FRONT.

WHILE SOME GUIDANCE PACKAGES ARE SUGGESTING THAT A 40KT LOW LEVEL JET
WILL BE IN PLACE BY 06Z...WILL KEEP OUT OF THE TAFS FOR NOW AS AT
LEAST A PORTION OF THESE WINDS MAY MIX TO THE SFC.

OUTLOOK... SUNDAY NIGHT...MAINLY VFR. SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS AFTER
06Z.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
HIGH PRESSURE NOSING NORTHEAST FROM THE OHIO VALLEY HAS LESSENED
THE SFC PRESSURE GRADIENT OVER THE LOWER GREAT LAKES...SO GENTLE
TO LIGHT WINDS CAN BE EXPECTED THROUGH DAYBREAK.

WHILE WINDS WILL FRESHEN AS WE PROGRESS THROUGH SUNDAY MORNING...
CONDITIONS ARE LIKELY TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE LOWER GREAT LAKES LATE SUNDAY
NIGHT AND MONDAY AND LIKELY BRING A ROUND OF SMALL CRAFT ADVISORY
CONDITIONS TO LAKES ERIE AND ONTARIO...ALONG WITH THE LIKELIHOOD
OF STRONG TO POTENTIALLY SEVERE THUNDERSTORMS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/RSH
MARINE...RSH





000
FXUS61 KBUF 020300
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1100 PM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IS CLEAR LATE THIS EVENING WITH THE MID-LEVEL TROUGH EAST OF
THE FORECAST AREA AND HIGH PRESSURE EDGING IN FROM THE OHIO VALLEY.
BOTH WILL WORK TO KEEP A DRY OVERNIGHT. EXPECT MAINLY CLEAR TO
PARTLY CLOUDY SKIES WITH JUST A FEW PATCHES OF STRATUS DRIFTING
ACROSS THE AREA. THERE WILL BE A WIDE RANGE IN LOWS TONIGHT WITH MID
60S ON THE LAKE PLAINS WHERE A BREEZE WILL STAY UP THROUGH THE
NIGHT. THE SOUTHERN TIER VALLEYS AND TUG HILL REGION WILL DECOUPLE
MORE...WITH LOWS IN THE LOWER TO MID 50S IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
RADAR IS CLEAR ACROSS THE FORECAST AREA LATE THIS EVENING WITH VFR
EXPECTED OVERNIGHT. MAINLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED
WITH JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE
JUST ENOUGH WIND TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE TOWARD 00Z MONDAY WITH AN
APPROACHING COLD FRONT. GUIDANCE INDICATES A 40+ KT LOW LEVEL JET
WILL SHIFT IN AHEAD OF THE COLD FRONT WHICH COULD BRING SOME WIND
SHEAR.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS. LLWS
POSSIBLE IN THE EVENING.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
WINDS HAVE DIMINISHED LATE THIS EVENING AS THE PRESSURE GRADIENT
RELAXES WITH HIGH PRESSURE BUILDING IN FROM THE OHIO VALLEY. WINDS
WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT CONDITIONS
ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 020300
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1100 PM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IS CLEAR LATE THIS EVENING WITH THE MID-LEVEL TROUGH EAST OF
THE FORECAST AREA AND HIGH PRESSURE EDGING IN FROM THE OHIO VALLEY.
BOTH WILL WORK TO KEEP A DRY OVERNIGHT. EXPECT MAINLY CLEAR TO
PARTLY CLOUDY SKIES WITH JUST A FEW PATCHES OF STRATUS DRIFTING
ACROSS THE AREA. THERE WILL BE A WIDE RANGE IN LOWS TONIGHT WITH MID
60S ON THE LAKE PLAINS WHERE A BREEZE WILL STAY UP THROUGH THE
NIGHT. THE SOUTHERN TIER VALLEYS AND TUG HILL REGION WILL DECOUPLE
MORE...WITH LOWS IN THE LOWER TO MID 50S IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
RADAR IS CLEAR ACROSS THE FORECAST AREA LATE THIS EVENING WITH VFR
EXPECTED OVERNIGHT. MAINLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED
WITH JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE
JUST ENOUGH WIND TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE TOWARD 00Z MONDAY WITH AN
APPROACHING COLD FRONT. GUIDANCE INDICATES A 40+ KT LOW LEVEL JET
WILL SHIFT IN AHEAD OF THE COLD FRONT WHICH COULD BRING SOME WIND
SHEAR.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS. LLWS
POSSIBLE IN THE EVENING.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
WINDS HAVE DIMINISHED LATE THIS EVENING AS THE PRESSURE GRADIENT
RELAXES WITH HIGH PRESSURE BUILDING IN FROM THE OHIO VALLEY. WINDS
WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT CONDITIONS
ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 020300
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1100 PM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND WARM CONDITIONS ON SUNDAY TO WRAP
UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND
MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER AIR THAT
WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IS CLEAR LATE THIS EVENING WITH THE MID-LEVEL TROUGH EAST OF
THE FORECAST AREA AND HIGH PRESSURE EDGING IN FROM THE OHIO VALLEY.
BOTH WILL WORK TO KEEP A DRY OVERNIGHT. EXPECT MAINLY CLEAR TO
PARTLY CLOUDY SKIES WITH JUST A FEW PATCHES OF STRATUS DRIFTING
ACROSS THE AREA. THERE WILL BE A WIDE RANGE IN LOWS TONIGHT WITH MID
60S ON THE LAKE PLAINS WHERE A BREEZE WILL STAY UP THROUGH THE
NIGHT. THE SOUTHERN TIER VALLEYS AND TUG HILL REGION WILL DECOUPLE
MORE...WITH LOWS IN THE LOWER TO MID 50S IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
RADAR IS CLEAR ACROSS THE FORECAST AREA LATE THIS EVENING WITH VFR
EXPECTED OVERNIGHT. MAINLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED
WITH JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE
JUST ENOUGH WIND TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.
LOW CHANCES OF -SHRA/TSRA ARRIVE TOWARD 00Z MONDAY WITH AN
APPROACHING COLD FRONT. GUIDANCE INDICATES A 40+ KT LOW LEVEL JET
WILL SHIFT IN AHEAD OF THE COLD FRONT WHICH COULD BRING SOME WIND
SHEAR.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS. LLWS
POSSIBLE IN THE EVENING.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
WINDS HAVE DIMINISHED LATE THIS EVENING AS THE PRESSURE GRADIENT
RELAXES WITH HIGH PRESSURE BUILDING IN FROM THE OHIO VALLEY. WINDS
WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT CONDITIONS
ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...HITCHCOCK/SMITH
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 012347
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
747 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY NEAR 8PM THIS EVENING IS SHOWING ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS WESTERN NEW YORK WITH A BAND OF MORE
INTENSE THUNDERSTORMS APPROACHING THE SAINT LAWRENCE RIVER AND
NORTH COUNTY FROM ACROSS THE CANADIAN BORDER. LINGERING CAPE TO
1000 J/KG AND BULK SHEAR OF 20-40 KTS HAS SUPPORTED A FEW STRONGER
CELLS WITH SMALL HAIL AND GUSTY WINDS. ALL OF THIS CONVECTION IS
SUPPORTED BY THE DIURNAL CYCLE IN THE PRESENCE OF BROAD MID-LEVEL
TROUGH ALOFT...AND WILL QUICKLY END BY MID EVENING WITH THE LOSS
OF DAYTIME HEATING.

OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
RADAR SHOWING THAT ISOLATED SHOWERS AND THUNDERSTORMS ARE WEAKENING
WITH THE LOSS OF DAYTIME HEATING. A FEW SHOWERS/TSRA MAY PASS NEAR
KROC AND KART WITH A SHRA NEAR KJHW BUT EXPECT THIS ACTIVITY WILL
END BY MID EVENING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH
JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE WESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID EVENING.
WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT RELAXES.
WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT
CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 012347
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
747 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY NEAR 8PM THIS EVENING IS SHOWING ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS WESTERN NEW YORK WITH A BAND OF MORE
INTENSE THUNDERSTORMS APPROACHING THE SAINT LAWRENCE RIVER AND
NORTH COUNTY FROM ACROSS THE CANADIAN BORDER. LINGERING CAPE TO
1000 J/KG AND BULK SHEAR OF 20-40 KTS HAS SUPPORTED A FEW STRONGER
CELLS WITH SMALL HAIL AND GUSTY WINDS. ALL OF THIS CONVECTION IS
SUPPORTED BY THE DIURNAL CYCLE IN THE PRESENCE OF BROAD MID-LEVEL
TROUGH ALOFT...AND WILL QUICKLY END BY MID EVENING WITH THE LOSS
OF DAYTIME HEATING.

OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
RADAR SHOWING THAT ISOLATED SHOWERS AND THUNDERSTORMS ARE WEAKENING
WITH THE LOSS OF DAYTIME HEATING. A FEW SHOWERS/TSRA MAY PASS NEAR
KROC AND KART WITH A SHRA NEAR KJHW BUT EXPECT THIS ACTIVITY WILL
END BY MID EVENING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH
JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE WESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID EVENING.
WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT RELAXES.
WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT
CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 012347
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
747 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY NEAR 8PM THIS EVENING IS SHOWING ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS WESTERN NEW YORK WITH A BAND OF MORE
INTENSE THUNDERSTORMS APPROACHING THE SAINT LAWRENCE RIVER AND
NORTH COUNTY FROM ACROSS THE CANADIAN BORDER. LINGERING CAPE TO
1000 J/KG AND BULK SHEAR OF 20-40 KTS HAS SUPPORTED A FEW STRONGER
CELLS WITH SMALL HAIL AND GUSTY WINDS. ALL OF THIS CONVECTION IS
SUPPORTED BY THE DIURNAL CYCLE IN THE PRESENCE OF BROAD MID-LEVEL
TROUGH ALOFT...AND WILL QUICKLY END BY MID EVENING WITH THE LOSS
OF DAYTIME HEATING.

OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
RADAR SHOWING THAT ISOLATED SHOWERS AND THUNDERSTORMS ARE WEAKENING
WITH THE LOSS OF DAYTIME HEATING. A FEW SHOWERS/TSRA MAY PASS NEAR
KROC AND KART WITH A SHRA NEAR KJHW BUT EXPECT THIS ACTIVITY WILL
END BY MID EVENING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH
JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE WESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID EVENING.
WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT RELAXES.
WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT
CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 012347
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
747 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY NEAR 8PM THIS EVENING IS SHOWING ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS WESTERN NEW YORK WITH A BAND OF MORE
INTENSE THUNDERSTORMS APPROACHING THE SAINT LAWRENCE RIVER AND
NORTH COUNTY FROM ACROSS THE CANADIAN BORDER. LINGERING CAPE TO
1000 J/KG AND BULK SHEAR OF 20-40 KTS HAS SUPPORTED A FEW STRONGER
CELLS WITH SMALL HAIL AND GUSTY WINDS. ALL OF THIS CONVECTION IS
SUPPORTED BY THE DIURNAL CYCLE IN THE PRESENCE OF BROAD MID-LEVEL
TROUGH ALOFT...AND WILL QUICKLY END BY MID EVENING WITH THE LOSS
OF DAYTIME HEATING.

OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENHANCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF
LAKE ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUNTRY DROP BACK INTO
THE MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES
WILL FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH
THE COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL
BELOW EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
RADAR SHOWING THAT ISOLATED SHOWERS AND THUNDERSTORMS ARE WEAKENING
WITH THE LOSS OF DAYTIME HEATING. A FEW SHOWERS/TSRA MAY PASS NEAR
KROC AND KART WITH A SHRA NEAR KJHW BUT EXPECT THIS ACTIVITY WILL
END BY MID EVENING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH
JUST A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE WESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID EVENING.
WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT RELAXES.
WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY... BUT
CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY
CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 011950
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
350 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY SHOWING SCATTERED STORMS DEVELOPING ACROSS SOUTHERN
ONTARIO. THIS IS IN RESPONSE TO A MINOR INCREASE IN LARGE SCALE
ASCENT AHEAD OF A SUBTLE SHORTWAVE CROSSING SOUTHERN ONTARIO...AND
MORE IMPORTANTLY ENHANCED LOW LEVEL CONVERGENCE NEAR LAKE BREEZE
BOUNDARIES. ANOTHER AREA OF SCATTERED SHOWERS AND ISOLATED STORMS
HAS DEVELOPED ACROSS THE SAINT LAWRENCE VALLEY.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR HAVE A GOOD HANDLE ON
THE DEVELOPING CONVECTION AND WILL BE FOLLOWED CLOSELY AS A GUIDE
INTO THE EVENING. FOLLOWING THE HIGH RES MODEL GUIDANCE AND RECENT
RADAR TRENDS...THE SOUTHERN ONTARIO CONVECTION WILL CROSS INTO
WESTERN NY ESPECIALLY ALONG THE WELL DEFINED CONVERGENCE BOUNDARY
EXTENDING FROM THE NORTHERN HALF OF THE BUFFALO METRO AREA INTO
GENESEE COUNTY. OTHER SCATTERED STORMS NEAR THE WEST END OF LAKE
ONTARIO MAY TRY TO CROSS THE LAKE AND REACH NIAGARA AND ORLEANS
COUNTIES BY EARLY EVENING...BUT WILL HAVE A DIFFICULT TIME CROSSING
THE STABLE AIR OVER THE LAKE. THE SAINT LAWRENCE VALLEY CONVECTION
WILL CONTINUE IN PLACE FROM THE THOUSAND ISLANDS REGION NORTHEAST
INTO THE NORTHERN ADIRONDACKS.

ALL OF THIS CONVECTION IS SUPPORTED BY THE DIURNAL CYCLE...AND WILL
QUICKLY END BY MID EVENING WITH THE LOSS OF DAYTIME HEATING.
OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENAHNCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF LAKE
ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUTNRY DROP BACK INTO THE
MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES WILL
FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH THE
COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL BELOW
EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VISIBLE SATELLITE IMAGERY SHOWING EXTENSIVE CUMULUS FIELDS THIS
AFTERNOON INLAND FROM THE STABILIZING INFLUENCE OF THE COOLER LAKES.
MOST OF THE AREA WILL STAY DRY THROUGH THIS EVENING...BUT WIDELY
SCATTERED STORMS WILL CONTINUE TO DEVELOP IN A FEW AREAS. EXPECT THE
BEST COVERAGE TO BE ACROSS THE SAINT LAWRENCE VALLEY MAINLY NORTH
AND EAST OF KART THROUGH MID EVENING WHERE DEEPER MOISTURE AND
INSTABILITY IS FOUND. A CONVERGENCE ZONE WILL ALSO SET UP VERY CLOSE
TO KIAG AND KBUF MARKING THE BOUNDARY BETWEEN THE STRONGER WSW FLOW
OFF LAKE ERIE AND THE WNW FLOW OFF THE NIAGARA PENINSULA. A FEW
WIDELY SCATTERED THUNDERSTORMS WILL DRIFT FROM SOUTHERN ONTARIO TO
NEAR KBUF AND KIAG FROM 19Z-23Z. VFR WILL PREVAIL...BUT ANY OF THESE
STORMS MAY PRODUCE VERY BRIEF MVFR/IFR CONDITIONS.

ANY ISOLATED CONVECTION WILL END BY MID EVENING WITH THE LOSS OF
DAYTIME HEATING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH JUST
A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL
CRAFT ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID
EVENING. WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT
RELAXES. WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY...
BUT CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT
ADVISORY CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK
MARINE...HITCHCOCK




000
FXUS61 KBUF 011950
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
350 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY SHOWING SCATTERED STORMS DEVELOPING ACROSS SOUTHERN
ONTARIO. THIS IS IN RESPONSE TO A MINOR INCREASE IN LARGE SCALE
ASCENT AHEAD OF A SUBTLE SHORTWAVE CROSSING SOUTHERN ONTARIO...AND
MORE IMPORTANTLY ENHANCED LOW LEVEL CONVERGENCE NEAR LAKE BREEZE
BOUNDARIES. ANOTHER AREA OF SCATTERED SHOWERS AND ISOLATED STORMS
HAS DEVELOPED ACROSS THE SAINT LAWRENCE VALLEY.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR HAVE A GOOD HANDLE ON
THE DEVELOPING CONVECTION AND WILL BE FOLLOWED CLOSELY AS A GUIDE
INTO THE EVENING. FOLLOWING THE HIGH RES MODEL GUIDANCE AND RECENT
RADAR TRENDS...THE SOUTHERN ONTARIO CONVECTION WILL CROSS INTO
WESTERN NY ESPECIALLY ALONG THE WELL DEFINED CONVERGENCE BOUNDARY
EXTENDING FROM THE NORTHERN HALF OF THE BUFFALO METRO AREA INTO
GENESEE COUNTY. OTHER SCATTERED STORMS NEAR THE WEST END OF LAKE
ONTARIO MAY TRY TO CROSS THE LAKE AND REACH NIAGARA AND ORLEANS
COUNTIES BY EARLY EVENING...BUT WILL HAVE A DIFFICULT TIME CROSSING
THE STABLE AIR OVER THE LAKE. THE SAINT LAWRENCE VALLEY CONVECTION
WILL CONTINUE IN PLACE FROM THE THOUSAND ISLANDS REGION NORTHEAST
INTO THE NORTHERN ADIRONDACKS.

ALL OF THIS CONVECTION IS SUPPORTED BY THE DIURNAL CYCLE...AND WILL
QUICKLY END BY MID EVENING WITH THE LOSS OF DAYTIME HEATING.
OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENAHNCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF LAKE
ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUTNRY DROP BACK INTO THE
MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES WILL
FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH THE
COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL BELOW
EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VISIBLE SATELLITE IMAGERY SHOWING EXTENSIVE CUMULUS FIELDS THIS
AFTERNOON INLAND FROM THE STABILIZING INFLUENCE OF THE COOLER LAKES.
MOST OF THE AREA WILL STAY DRY THROUGH THIS EVENING...BUT WIDELY
SCATTERED STORMS WILL CONTINUE TO DEVELOP IN A FEW AREAS. EXPECT THE
BEST COVERAGE TO BE ACROSS THE SAINT LAWRENCE VALLEY MAINLY NORTH
AND EAST OF KART THROUGH MID EVENING WHERE DEEPER MOISTURE AND
INSTABILITY IS FOUND. A CONVERGENCE ZONE WILL ALSO SET UP VERY CLOSE
TO KIAG AND KBUF MARKING THE BOUNDARY BETWEEN THE STRONGER WSW FLOW
OFF LAKE ERIE AND THE WNW FLOW OFF THE NIAGARA PENINSULA. A FEW
WIDELY SCATTERED THUNDERSTORMS WILL DRIFT FROM SOUTHERN ONTARIO TO
NEAR KBUF AND KIAG FROM 19Z-23Z. VFR WILL PREVAIL...BUT ANY OF THESE
STORMS MAY PRODUCE VERY BRIEF MVFR/IFR CONDITIONS.

ANY ISOLATED CONVECTION WILL END BY MID EVENING WITH THE LOSS OF
DAYTIME HEATING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH JUST
A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL
CRAFT ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID
EVENING. WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT
RELAXES. WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY...
BUT CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT
ADVISORY CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK
MARINE...HITCHCOCK





000
FXUS61 KBUF 011950
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
350 PM EDT SAT AUG 1 2015

.SYNOPSIS...
A FEW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL END LATER THIS
EVENING. HIGH PRESSURE WILL THEN BRING DRY AND WARM CONDITIONS ON
SUNDAY TO WRAP UP THE WEEKEND. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT AND MONDAY WITH A BETTER CHANCE OF MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS. THIS COLD FRONT WILL USHER IN MUCH COOLER
AIR THAT WILL LAST FOR ALL OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
RADAR IMAGERY SHOWING SCATTERED STORMS DEVELOPING ACROSS SOUTHERN
ONTARIO. THIS IS IN RESPONSE TO A MINOR INCREASE IN LARGE SCALE
ASCENT AHEAD OF A SUBTLE SHORTWAVE CROSSING SOUTHERN ONTARIO...AND
MORE IMPORTANTLY ENHANCED LOW LEVEL CONVERGENCE NEAR LAKE BREEZE
BOUNDARIES. ANOTHER AREA OF SCATTERED SHOWERS AND ISOLATED STORMS
HAS DEVELOPED ACROSS THE SAINT LAWRENCE VALLEY.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR HAVE A GOOD HANDLE ON
THE DEVELOPING CONVECTION AND WILL BE FOLLOWED CLOSELY AS A GUIDE
INTO THE EVENING. FOLLOWING THE HIGH RES MODEL GUIDANCE AND RECENT
RADAR TRENDS...THE SOUTHERN ONTARIO CONVECTION WILL CROSS INTO
WESTERN NY ESPECIALLY ALONG THE WELL DEFINED CONVERGENCE BOUNDARY
EXTENDING FROM THE NORTHERN HALF OF THE BUFFALO METRO AREA INTO
GENESEE COUNTY. OTHER SCATTERED STORMS NEAR THE WEST END OF LAKE
ONTARIO MAY TRY TO CROSS THE LAKE AND REACH NIAGARA AND ORLEANS
COUNTIES BY EARLY EVENING...BUT WILL HAVE A DIFFICULT TIME CROSSING
THE STABLE AIR OVER THE LAKE. THE SAINT LAWRENCE VALLEY CONVECTION
WILL CONTINUE IN PLACE FROM THE THOUSAND ISLANDS REGION NORTHEAST
INTO THE NORTHERN ADIRONDACKS.

ALL OF THIS CONVECTION IS SUPPORTED BY THE DIURNAL CYCLE...AND WILL
QUICKLY END BY MID EVENING WITH THE LOSS OF DAYTIME HEATING.
OVERNIGHT EXPECT MAINLY CLEAR TO PARTLY CLOUDY SKIES WITH JUST A FEW
PATCHES OF STRATUS DRIFTING ACROSS THE AREA. THERE WILL BE A WIDE
RANGE IN LOWS TONIGHT WITH MID 60S ON THE LAKE PLAINS WHERE A BREEZE
WILL STAY UP THROUGH THE NIGHT. THE SOUTHERN TIER VALLEYS AND TUG
HILL REGION WILL DECOUPLE MORE...WITH LOWS IN THE LOWER TO MID 50S
IN THE COOLEST LOCATIONS.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO
THE MID ATLANTIC. THIS HIGH WILL BE CLOSE ENOUGH TO PROVIDE
SUBSIDENCE AND DRYING...WHICH WILL LIKELY PREVENT ANY DIURNAL
CONVECTION DESPITE THE WARM TEMPERATURES. EXPECT NOTHING MORE THAN
SCT DIURNAL CUMULUS TO DEVELOP ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES AND ALSO SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS
DURING THE AFTERNOON. WARM ADVECTION AHEAD OF THE NEXT SYSTEM WILL
BOOST 850MB TEMPS TO AROUND +16...WHICH WILL SUPPORT HIGHS IN THE
MID 80S ACROSS LOWER ELEVATIONS AND AROUND 80 ON THE HILLS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
SUNDAY NIGHT A SHORTWAVE TROUGH OF LOW PRESSURE WILL DIG TOWARDS
THE BASE OF AN UPPER LEVEL LOW THAT IS SPINNING OVER ONTARIO
PROVINCE CANADA. AT THE SURFACE AN AREA OF LOW PRESSURE NEAR THE
SOUTHERN TIP OF JAMES BAY WILL BE DRAGGING A COLD FRONT ACROSS THE
CENTRAL GREAT LAKES.

FOR OUR REGION A WARM AND SOMEWHAT HUMID NIGHT IS ON TAP AS A STRONG
LOW LEVEL JET OF 45 TO 60 KNOTS WITHIN THE 850 - 700 HPA LAYER
STRENGTHENS THE WARM AIR ADVECTION. THIS JET WILL ALSO BE DRAWING
MOISTURE NORTHWARD AS PWATS CLIMB TO NEAR 1.5 INCHES ACROSS
WESTERN AND CENTRAL NEW YORK THROUGH THE NIGHT.

THE COLD FRONT WILL BE SLICING ACROSS THE CENTRAL GREAT LAKES REGION
SUNDAY NIGHT...TO BE KNOCKING ON OUR WESTERN DOORSTEPS MONDAY
MORNING. THROUGH THE OVERNIGHT A FEW SHOWERS ARE POSSIBLE AS
CONVERGENCE AHEAD OF THE LOW LEVEL JET PRODUCES ENOUGH LIFT TO FORM
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. GREATEST COVERAGE
AREA WILL BE NEAR THE LAKES...WHICH WILL BE HOLDING ONTO INSTABILITY
THROUGH THE OVERNIGHT. LATER IN THE NIGHT SHOWERS WILL BEGIN TO
INCREASE IN NUMBER ACROSS FAR WESTERN NEW YORK AND THE SAINT
LAWRENCE VALLEY AS THE COLD FRONT DRAWS NEAR.

ON MONDAY THE UPPER LEVEL SHORTWAVE WILL BE PUSHING A FAIRLY STRONG
COLD FRONT ACROSS THE REGION. AHEAD OF THE COLD FRONT A PREFRONTAL
TROUGH IS EXPECTED TO FORM WITH A LINE OF SHOWERS AND THUNDERSTORMS
ADVANCING EASTWARD ACROSS THE BUFFALO CWA. CURRENT MODEL/THINKING
FOR THE TIMING OF THIS INITIAL LINE OF STORMS IS TO BE ACROSS WNY
MONDAY MORNING...REACHING CENTRAL NEW YORK MIDDAY. THOUGH THIS IS AN
EARLY IN THE DAY TIMING TO THE BAND OF THUNDERSTORMS (AND NOT DURING
THE TIME OF PEAK HEATING AND INSTABILITY)...THERE WILL STILL BE A
DECENT AMOUNT OF INSTABILITY AROUND COUPLED WITH STEEPING LAPSE
RATES TO NEAR 7 TO 8 C/KM AND 0-6KM BULK SHEAR VALUES UP TO 40 KNOTS
TO ALLOW A FEW OF THESE THUNDERSTORMS TO BECOME STRONG TO POSSIBLY
SEVERE. WILL MENTION THIS PROSPECT IN THE HWO.

FOLLOWING THE INITIAL LINE OF SHOWERS AND THUNDERSTORMS THERE WILL
BE A BRIEF BREAK IN PRECIPITATION. IN FACT THE SUN MIGHT EVEN APPEAR
BRIEFLY DURING THE MIDDAY AND EARLY AFTERNOON HOURS. WITHIN THIS
SUNSHINE SOUTHWEST WINDS COULD BECOME GUSTY AS MIXING HEIGHTS RISE.
GUSTS UP TO 20 TO 25 MPH...AND NEAR 30 MPH DOWNWIND OF THE EASTERN
GREAT LAKES WILL BE POSSIBLE AHEAD OF THE COLD FRONT. CLOUDS WILL
THICKEN AGAIN IN THE AFTERNOON AND SHOWER CHANCES SHALL INCREASE
WITH THE LATE DAY PASSAGE OF THE SURFACE COLD FRONT. MUCH OF THE
INSTABILITY WILL LIKELY BE USED TO FUEL THE INITIAL LINE OF
STORMS...SUCH THAT THE SECOND LINE WILL TEND TO BE MORE OF A BROKEN
LINE OF SHOWERS WITH ISOLATED THUNDER CHANCES.

FOLLOWING THE PASSAGE OF THIS COLD FRONT OUR 850 HPA TEMPERATURES
WILL DROP FROM THE HIGH TEENS DOWN TO NEAR 10C BY TUESDAY MORNING.
SHOWER CHANCES WILL DIMINISH THROUGH THE NIGHT MONDAY NIGHT WITH
SOME PATCHY AREAS OF FOG FORMING OVER A WET GROUND.

TUESDAY WILL HAVE MORE OF A FALLISH FEEL TO THE DAY AS A POOL OF
COLD AIR ALOFT PASSES OVER THE EASTERN GREAT LAKES. TEMPERATURES AT
850 HPA IN THE HIGH SINGLE DIGITS WILL GENERATE STEEP LAPSE RATES
THAT COULD GENERATE A FEW SHOWERS. IN ADDITION TO THE INSTABILITY
SHOWERS A WESTERLY FLOW OVER THE WARM GREAT LAKES COULD BRING SOME
LAKE ENAHNCED SHOWERS ACROSS SW NYS AS WELL AS SE AND EAST OF LAKE
ONTARIO. EXPECT SHOWER COVERAGE TO DIMINISH THROUGH THE NIGHT
TUESDAY NIGHT AS LAPSE RATES WEAKEN WITH THE SETTING SUN.

TEMPERATURES SUNDAY NIGHT WILL REMAIN MILD OVERNIGHT WITH LOWS
REMAINING IN THE LOWER 70S FOR MOST LOCATIONS NEAR THE GREAT
LAKES...WHILE INLAND AREAS AND THE NORTH COUTNRY DROP BACK INTO THE
MID TO UPPER 60S. ON MONDAY THESE SEASONABLY WARM TEMPERATURES WILL
FALL BACK INTO THE UPPER 50S AND LOWER 60S MONDAY NIGHT. WITH THE
COOL POOL OVER THE REGION TUESDAY EXPECT HIGHS TO BE WELL BELOW
EARLY AUGUST NORMALS...WITH HIGHS ONLY IN THE LOWER 70S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN UPPER LEVEL TROUGH WILL START THIS TIME PERIOD OVER EASTERN
CANADA...WITH BELOW NORMAL TEMPERATURES FOUND UNDER THIS FEATURE.
THIS TROUGH WILL WEAKEN SOME THROUGH THE TIME PERIOD BUT WILL
REMAIN GENERALLY IN PLACE AND NOT ALLOW FOR AN UPPER LEVEL RIDGE
FOUND OVER THE DESERT SOUTHWEST...AND PLAIN STATES TO PUSH
EASTWARD TO THE ATLANTIC COASTLINE.

MOISTURE WILL BE LIMITED THE FIRST PART OF THE EXTENDED TIME FRAME
WITH PARTLY SUNNY SKIES PREDOMINATE. THERE WILL BE SMALL CHANCES FOR
SHOWERS...WITH CONFIDENCE FOR CHANCE POPS ONLY EAST OF LAKE ONTARIO
WHICH WILL BE CLOSER TO BOTH THE UPPER LEVEL TROUGH AND DEEPER
MOISTURE. IN ADDITION ON WEDNESDAY A COOL POOL ALOFT MAY BRING
ENOUGH INSTABILITY OVER LAKE ONTARIO TO BRING SOME LAKE ENHANCED
RAIN SHOWERS SE AND E OF THE LAKE.

TOWARDS THE END OF THE EXTENDED PERIOD DEEPER MOISTURE WILL ADVECT
NORTHWARD AND ADDITIONAL SHORTWAVES ROUNDING THE UPPER LEVEL TROUGH
WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO CLOSE
OUT THE EXTENDED. TEMPERATURES WILL REMAIN SLIGHTLY COOLER THAN
NORMAL THIS PERIOD.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VISIBLE SATELLITE IMAGERY SHOWING EXTENSIVE CUMULUS FIELDS THIS
AFTERNOON INLAND FROM THE STABILIZING INFLUENCE OF THE COOLER LAKES.
MOST OF THE AREA WILL STAY DRY THROUGH THIS EVENING...BUT WIDELY
SCATTERED STORMS WILL CONTINUE TO DEVELOP IN A FEW AREAS. EXPECT THE
BEST COVERAGE TO BE ACROSS THE SAINT LAWRENCE VALLEY MAINLY NORTH
AND EAST OF KART THROUGH MID EVENING WHERE DEEPER MOISTURE AND
INSTABILITY IS FOUND. A CONVERGENCE ZONE WILL ALSO SET UP VERY CLOSE
TO KIAG AND KBUF MARKING THE BOUNDARY BETWEEN THE STRONGER WSW FLOW
OFF LAKE ERIE AND THE WNW FLOW OFF THE NIAGARA PENINSULA. A FEW
WIDELY SCATTERED THUNDERSTORMS WILL DRIFT FROM SOUTHERN ONTARIO TO
NEAR KBUF AND KIAG FROM 19Z-23Z. VFR WILL PREVAIL...BUT ANY OF THESE
STORMS MAY PRODUCE VERY BRIEF MVFR/IFR CONDITIONS.

ANY ISOLATED CONVECTION WILL END BY MID EVENING WITH THE LOSS OF
DAYTIME HEATING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH JUST
A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL
CRAFT ADVISORY CONDITIONS ON LAKES ERIE AND ONTARIO THROUGH MID
EVENING. WINDS WILL DIMINISH OVERNIGHT AS THE PRESSURE GRADIENT
RELAXES. WINDS WILL INCREASE TO AROUND 15 KNOTS AGAIN ON SUNDAY...
BUT CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT
ADVISORY CRITERIA.

A STRONGER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
AND LIKELY BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS TO
LAKES ERIE AND ONTARIO.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK
MARINE...HITCHCOCK





000
FXUS61 KBUF 011729
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
129 PM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL NOSE NORTHWARDS TO
THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL PROVIDE THE BULK OF
OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER IMPULSE OF
ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR LATER THIS
AFTERNOON AND EVENING. AS OF 17Z THIS CAN BE SEEN IN WATER VAPOR
IMAGERY MOVING EAST OF GEORGIAN BAY. THIS WEAK VORTICITY MAXIMA WILL
PROVIDE MODEST LARGE SCALE ASCENT DURING THE LATE AFTERNOON AND
EVENING AS IT CROSSES THE LOWER LAKES.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR ARE NOT DEVELOPING MUCH
IN THE WAY OF CONVECTION THIS AFTERNOON WITH A FEW EXCEPTIONS.
SOMEWHAT DEEPER MOISTURE AND BETTER ASCENT THIS AFTERNOON ACROSS THE
SAINT LAWRENCE VALLEY SHOULD SUPPORT SCATTERED CONVECTION WITH
DAYTIME HEATING...MAINLY NORTH AND EAST OF THE WATERTOWN AREA. THE
HIGH RES GUIDANCE ALSO TARGETS THE NIAGARA FRONTIER CONVERGENCE ZONE
FOR LATE AFTERNOON AND EARLY EVENING CONVECTION. THE ENHANCED WSW
FLOW OFF LAKE ERIE AND GENERAL WNW FLOW OVER THE NIAGARA PENINSULA
WILL DEVELOP A NICE CONVERGENCE ZONE FROM NEAR GRAND ISLAND ACROSS
THE NORTHERN SUBURBS OF BUFFALO AND INTO GENESEE COUNTY LATER THIS
AFTERNOON...A LITTLE SOUTH OF ITS CLIMATOLOGICAL PLACEMENT GIVEN THE
WNW FLOW ALOFT. THIS BOUNDARY MAY BE THE FOCUS FOR A FEW HOURS OF
WIDELY SCATTERED CONVECTION FROM MID TO LATE AFTERNOON INTO THE
EVENING. OUTSIDE OF THE TWO AREAS MENTIONED ABOVE...EXPECT ANY
AFTERNOON CONVECTIVE COVERAGE TO REMAIN VERY SPARSE...IF ANYTHING
FORMS AT ALL. STABLE LAKE SHADOWS EAST OF LAKE ERIE AND ONTARIO WILL
KEEP AREAS EAST OF BOTH LAKES DRY.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VISIBLE SATELLITE IMAGERY SHOWING EXTENSIVE CUMULUS FIELDS THIS
AFTERNOON INLAND FROM THE STABILIZING INFLUENCE OF THE COOLER LAKES.
MOST OF THE AREA WILL STAY DRY THROUGH THIS EVENING...BUT WIDELY
SCATTERED STORMS WILL DEVELOP IN A FEW AREAS. EXPECT THE BEST
COVERAGE TO BE ACROSS THE SAINT LAWRENCE VALLEY MAINLY NORTH AND EAST
OF KART FROM MID AFTERNOON THROUGH MID EVENING WHERE DEEPER MOISTURE
AND INSTABILITY IS FOUND. A CONVERGENCE ZONE WILL ALSO SET UP VERY
CLOSE TO KIAG AND KBUF MARKING THE BOUNDARY BETWEEN THE STRONGER WSW
FLOW OFF LAKE ERIE AND THE WNW FLOW OFF THE NIAGARA PENINSULA. THIS
MAY ALLOW A FEW WIDELY SCATTERED THUNDERSTORMS TO DEVELOP FROM ABOUT
20Z-00Z NEAR KBUF AND KIAG. VFR WILL PREVAIL...BUT ANY OF THESE
STORMS MAY PRODUCE VERY BRIEF MVFR/IFR CONDITIONS.

ANY ISOLATED CONVECTION WILL END BY MID EVENING WITH THE LOSS OF
DAYTIME HEATING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH JUST
A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...HITCHCOCK
MARINE...RSH





000
FXUS61 KBUF 011729
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
129 PM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL NOSE NORTHWARDS TO
THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL PROVIDE THE BULK OF
OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER IMPULSE OF
ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR LATER THIS
AFTERNOON AND EVENING. AS OF 17Z THIS CAN BE SEEN IN WATER VAPOR
IMAGERY MOVING EAST OF GEORGIAN BAY. THIS WEAK VORTICITY MAXIMA WILL
PROVIDE MODEST LARGE SCALE ASCENT DURING THE LATE AFTERNOON AND
EVENING AS IT CROSSES THE LOWER LAKES.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR ARE NOT DEVELOPING MUCH
IN THE WAY OF CONVECTION THIS AFTERNOON WITH A FEW EXCEPTIONS.
SOMEWHAT DEEPER MOISTURE AND BETTER ASCENT THIS AFTERNOON ACROSS THE
SAINT LAWRENCE VALLEY SHOULD SUPPORT SCATTERED CONVECTION WITH
DAYTIME HEATING...MAINLY NORTH AND EAST OF THE WATERTOWN AREA. THE
HIGH RES GUIDANCE ALSO TARGETS THE NIAGARA FRONTIER CONVERGENCE ZONE
FOR LATE AFTERNOON AND EARLY EVENING CONVECTION. THE ENHANCED WSW
FLOW OFF LAKE ERIE AND GENERAL WNW FLOW OVER THE NIAGARA PENINSULA
WILL DEVELOP A NICE CONVERGENCE ZONE FROM NEAR GRAND ISLAND ACROSS
THE NORTHERN SUBURBS OF BUFFALO AND INTO GENESEE COUNTY LATER THIS
AFTERNOON...A LITTLE SOUTH OF ITS CLIMATOLOGICAL PLACEMENT GIVEN THE
WNW FLOW ALOFT. THIS BOUNDARY MAY BE THE FOCUS FOR A FEW HOURS OF
WIDELY SCATTERED CONVECTION FROM MID TO LATE AFTERNOON INTO THE
EVENING. OUTSIDE OF THE TWO AREAS MENTIONED ABOVE...EXPECT ANY
AFTERNOON CONVECTIVE COVERAGE TO REMAIN VERY SPARSE...IF ANYTHING
FORMS AT ALL. STABLE LAKE SHADOWS EAST OF LAKE ERIE AND ONTARIO WILL
KEEP AREAS EAST OF BOTH LAKES DRY.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VISIBLE SATELLITE IMAGERY SHOWING EXTENSIVE CUMULUS FIELDS THIS
AFTERNOON INLAND FROM THE STABILIZING INFLUENCE OF THE COOLER LAKES.
MOST OF THE AREA WILL STAY DRY THROUGH THIS EVENING...BUT WIDELY
SCATTERED STORMS WILL DEVELOP IN A FEW AREAS. EXPECT THE BEST
COVERAGE TO BE ACROSS THE SAINT LAWRENCE VALLEY MAINLY NORTH AND EAST
OF KART FROM MID AFTERNOON THROUGH MID EVENING WHERE DEEPER MOISTURE
AND INSTABILITY IS FOUND. A CONVERGENCE ZONE WILL ALSO SET UP VERY
CLOSE TO KIAG AND KBUF MARKING THE BOUNDARY BETWEEN THE STRONGER WSW
FLOW OFF LAKE ERIE AND THE WNW FLOW OFF THE NIAGARA PENINSULA. THIS
MAY ALLOW A FEW WIDELY SCATTERED THUNDERSTORMS TO DEVELOP FROM ABOUT
20Z-00Z NEAR KBUF AND KIAG. VFR WILL PREVAIL...BUT ANY OF THESE
STORMS MAY PRODUCE VERY BRIEF MVFR/IFR CONDITIONS.

ANY ISOLATED CONVECTION WILL END BY MID EVENING WITH THE LOSS OF
DAYTIME HEATING. THIS WILL LEAVE VFR TO PREVAIL OVERNIGHT WITH JUST
A FEW PATCHES OF VFR LEVEL STRATUS. THERE SHOULD BE ENOUGH WIND
TO PREVENT ANY RIVER VALLEY FOG LATE TONIGHT.

ON SUNDAY HIGH PRESSURE WILL REMAIN IN CONTROL FROM THE OHIO VALLEY
TO THE MID ATLANTIC. THIS SHOULD PROVIDE ENOUGH SUBSIDENCE TO
PREVENT ANY CONVECTION UNTIL A SYSTEM BEGINS TO APPROACH FROM THE
WEST SUNDAY EVENING. VFR WILL PREVAIL THROUGH THE DAY WITH JUST SCT
DIURNAL CUMULUS AND SOME MODEST INCREASE IN CIRRUS LEVEL CLOUDINESS.

OUTLOOK...
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS
AND ASSOCIATED BRIEF/LOCAL MVFR/IFR CONDITIONS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY AND THURSDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...HITCHCOCK
MARINE...RSH




000
FXUS61 KBUF 011427
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1027 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY THIS MORNING WILL NOSE
NORTHWARDS TO THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH
ANOTHER IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED
FOR LATER THIS AFTERNOON AND EVENING. AS OF 14Z THIS CAN BE SEEN IN
WATER VAPOR IMAGERY CROSSING LAKE HURON. THIS WEAK VORTICITY MAXIMA
WILL PROVIDE MODEST LARGE SCALE ASCENT DURING THE LATE AFTERNOON AND
EVENING AS IT CROSSES THE LOWER LAKES.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR ARE NOT DEVELOPING MUCH
IN THE WAY OF CONVECTION THIS AFTERNOON WITH A FEW EXCEPTIONS.
SOMEWHAT DEEPER MOISTURE AND BETTER ASCENT THIS AFTERNOON ACROSS THE
SAINT LAWRENCE VALLEY SHOULD SUPPORT SCATTERED CONVECTION WITH
DAYTIME HEATING...MAINLY NORTH AND EAST OF THE WATERTOWN AREA. THE
HIGH RES GUIDANCE ALSO TARGETS THE NIAGARA FRONTIER CONVERGENCE ZONE
FOR LATE AFTERNOON AND EARLY EVENING CONVECTION. THE ENHANCED WSW
FLOW OFF LAKE ERIE AND GENERAL WNW FLOW OVER THE NIAGARA PENINSULA
WILL DEVELOP A NICE CONVERGENCE ZONE FROM NEAR GRAND ISLAND ACROSS
THE NORTHERN SUBURBS OF BUFFALO AND INTO GENESEE COUNTY LATER THIS
AFTERNOON...A LITTLE SOUTH OF ITS CLIMATOLOGICAL PLACEMENT GIVEN THE
WNW FLOW ALOFT. THIS BOUNDARY MAY BE THE FOCUS FOR A FEW HOURS OF
WIDELY SCATTERED CONVECTION FROM MID TO LATE AFTERNOON INTO THE
EVENING. OUTSIDE OF THE TWO AREAS MENTIONED ABOVE...EXPECT ANY
AFTERNOON CONVECTIVE COVERAGE TO REMAIN VERY SPARSE...IF ANYTHING
FORMS AT ALL. STABLE LAKE SHADOWS EAST OF LAKE ERIE AND ONTARIO WILL
KEEP AREAS EAST OF BOTH LAKES DRY.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE LOWER
GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH FAIR DRY
WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON SHOWERS OR
THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE STABILIZING INFLUENCES
OF THE LAKES. THE BEST CHANCES WILL BE NEAR KIAG AND KBUF FROM ABOUT
20Z-01Z AS A CONVERGENCE ZONE DEVELOPS NEAR THOSE TAF SITES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...HITCHCOCK/RSH
MARINE...RSH





000
FXUS61 KBUF 011427
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1027 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY THIS MORNING WILL NOSE
NORTHWARDS TO THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH
ANOTHER IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED
FOR LATER THIS AFTERNOON AND EVENING. AS OF 14Z THIS CAN BE SEEN IN
WATER VAPOR IMAGERY CROSSING LAKE HURON. THIS WEAK VORTICITY MAXIMA
WILL PROVIDE MODEST LARGE SCALE ASCENT DURING THE LATE AFTERNOON AND
EVENING AS IT CROSSES THE LOWER LAKES.

LATEST HIGH RESOLUTION MESOSCALE MODEL GUIDANCE SUCH AS THE HRRR...
OPERATIONAL NAM...AND EXPERIMENTAL 3KM NAMRR ARE NOT DEVELOPING MUCH
IN THE WAY OF CONVECTION THIS AFTERNOON WITH A FEW EXCEPTIONS.
SOMEWHAT DEEPER MOISTURE AND BETTER ASCENT THIS AFTERNOON ACROSS THE
SAINT LAWRENCE VALLEY SHOULD SUPPORT SCATTERED CONVECTION WITH
DAYTIME HEATING...MAINLY NORTH AND EAST OF THE WATERTOWN AREA. THE
HIGH RES GUIDANCE ALSO TARGETS THE NIAGARA FRONTIER CONVERGENCE ZONE
FOR LATE AFTERNOON AND EARLY EVENING CONVECTION. THE ENHANCED WSW
FLOW OFF LAKE ERIE AND GENERAL WNW FLOW OVER THE NIAGARA PENINSULA
WILL DEVELOP A NICE CONVERGENCE ZONE FROM NEAR GRAND ISLAND ACROSS
THE NORTHERN SUBURBS OF BUFFALO AND INTO GENESEE COUNTY LATER THIS
AFTERNOON...A LITTLE SOUTH OF ITS CLIMATOLOGICAL PLACEMENT GIVEN THE
WNW FLOW ALOFT. THIS BOUNDARY MAY BE THE FOCUS FOR A FEW HOURS OF
WIDELY SCATTERED CONVECTION FROM MID TO LATE AFTERNOON INTO THE
EVENING. OUTSIDE OF THE TWO AREAS MENTIONED ABOVE...EXPECT ANY
AFTERNOON CONVECTIVE COVERAGE TO REMAIN VERY SPARSE...IF ANYTHING
FORMS AT ALL. STABLE LAKE SHADOWS EAST OF LAKE ERIE AND ONTARIO WILL
KEEP AREAS EAST OF BOTH LAKES DRY.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE LOWER
GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH FAIR DRY
WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON SHOWERS OR
THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE STABILIZING INFLUENCES
OF THE LAKES. THE BEST CHANCES WILL BE NEAR KIAG AND KBUF FROM ABOUT
20Z-01Z AS A CONVERGENCE ZONE DEVELOPS NEAR THOSE TAF SITES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...HITCHCOCK/RSH
MARINE...RSH




000
FXUS61 KBUF 011143
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
743 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY THIS MORNING WILL NOSE
NORTHWARDS TO THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH
ANOTHER IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED
FOR LATER THIS AFTERNOON AND EVENING. AS OF 11Z...THE SHORTWAVE
COULD BE SEEN IN WV IMAGERY DIGGING ITS WAY SOUTHEASTWARD FROM LAKE
SUPERIOR. IT WILL CROSS LAKE ONTARIO LATER THIS AFTERNOON AND EARLY
EVENING...JUST AS OUR AIRMASS REACHES ITS GREATEST DIURNAL
INSTABILITY. SBCAPES WILL APPROACH 1000 J/KG AT THE TIME OF ITS
PASSAGE...BUT WITH A RELATIVELY DRY AIRMASS IN PLACE AND A STRONG
LAKE BREEZE EXTENDING NORTHEAST FROM LAKE ERIE...THE CONVECTION IS
NOT EXPECTED TO BE WIDESPREAD. THE GREATEST CHANCE FOR ANY
THUNDERSTORM ACTIVITY WILL BE FOUND WELL INLAND FROM LAKE ERIE AND
ITS SHADOW...PLACING THE FOCUS FROM ABOUT GENESEE COUNTY TO THE
FINGER LAKES REGION. ALL IN ALL THOUGH...THE DAY WILL BE LARGELY
RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE LOWER
GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH FAIR DRY
WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON SHOWERS OR
THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE STABILIZING INFLUENCES
OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 011143
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
743 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY THIS MORNING WILL NOSE
NORTHWARDS TO THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH
ANOTHER IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED
FOR LATER THIS AFTERNOON AND EVENING. AS OF 11Z...THE SHORTWAVE
COULD BE SEEN IN WV IMAGERY DIGGING ITS WAY SOUTHEASTWARD FROM LAKE
SUPERIOR. IT WILL CROSS LAKE ONTARIO LATER THIS AFTERNOON AND EARLY
EVENING...JUST AS OUR AIRMASS REACHES ITS GREATEST DIURNAL
INSTABILITY. SBCAPES WILL APPROACH 1000 J/KG AT THE TIME OF ITS
PASSAGE...BUT WITH A RELATIVELY DRY AIRMASS IN PLACE AND A STRONG
LAKE BREEZE EXTENDING NORTHEAST FROM LAKE ERIE...THE CONVECTION IS
NOT EXPECTED TO BE WIDESPREAD. THE GREATEST CHANCE FOR ANY
THUNDERSTORM ACTIVITY WILL BE FOUND WELL INLAND FROM LAKE ERIE AND
ITS SHADOW...PLACING THE FOCUS FROM ABOUT GENESEE COUNTY TO THE
FINGER LAKES REGION. ALL IN ALL THOUGH...THE DAY WILL BE LARGELY
RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE LOWER
GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH FAIR DRY
WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON SHOWERS OR
THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE STABILIZING INFLUENCES
OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 011143
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
743 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY THIS MORNING WILL NOSE
NORTHWARDS TO THE LOWER GREAT LAKES THIS AFTERNOON. THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH
ANOTHER IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED
FOR LATER THIS AFTERNOON AND EVENING. AS OF 11Z...THE SHORTWAVE
COULD BE SEEN IN WV IMAGERY DIGGING ITS WAY SOUTHEASTWARD FROM LAKE
SUPERIOR. IT WILL CROSS LAKE ONTARIO LATER THIS AFTERNOON AND EARLY
EVENING...JUST AS OUR AIRMASS REACHES ITS GREATEST DIURNAL
INSTABILITY. SBCAPES WILL APPROACH 1000 J/KG AT THE TIME OF ITS
PASSAGE...BUT WITH A RELATIVELY DRY AIRMASS IN PLACE AND A STRONG
LAKE BREEZE EXTENDING NORTHEAST FROM LAKE ERIE...THE CONVECTION IS
NOT EXPECTED TO BE WIDESPREAD. THE GREATEST CHANCE FOR ANY
THUNDERSTORM ACTIVITY WILL BE FOUND WELL INLAND FROM LAKE ERIE AND
ITS SHADOW...PLACING THE FOCUS FROM ABOUT GENESEE COUNTY TO THE
FINGER LAKES REGION. ALL IN ALL THOUGH...THE DAY WILL BE LARGELY
RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE LOWER
GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH FAIR DRY
WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON SHOWERS OR
THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE STABILIZING INFLUENCES
OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH




000
FXUS61 KBUF 010820
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
420 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A FAIRLY ROBUST MID LEVEL DISTURBANCE TRACKING EAST ACROSS LAKE
ONTARIO (AS OF THE WRITING OF THIS DISCUSSION) PUSHED A COOL
FRONTAL BOUNDARY ACROSS OUR FORECAST AREA OVERNIGHT. THIS RESULTED
IN A FEW SHOWERS AND THUNDERSTORMS...PARTICULARLY OVER THE EASTERN
LAKE ONTARIO REGION WHERE THE CONVECTION INTENSIFIED TO SEVERE
LEVELS. THIS ACTIVITY HAS SINCE WEAKENED AND IS NOW IN THE PROCESS
OF PUSHING EAST ACROSS THE ADIRONDACKS.

AS FOR TODAY...HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL
NOSE NORTHWARDS TO THE LOWER GREAT LAKES. THIS WILL PROVIDE THE
BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER
IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR
THIS AFTERNOON AND EVENING. AS OF 08Z...THE SHORTWAVE COULD BE
SEEN IN WV IMAGERY DIGGING ITS WAY SOUTHEASTWARD ACROSS LAKE
SUPERIOR. IT WILL CROSS LAKE ONTARIO LATER THIS AFTERNOON AND
EARLY EVENING...JUST AS OUR AIRMASS REACHES ITS GREATEST DIURNAL
INSTABILITY. SBCAPES WILL APPROACH 1000 J/KG AT THE TIME OF ITS
PASSAGE...BUT WITH A RELATIVELY DRY AIRMASS IN PLACE AND A STRONG
LAKE BREEZE EXTENDING NORTHEAST FROM LAKE ERIE...THE CONVECTION IS
NOT EXPECTED TO BE WIDESPREAD. THE GREATEST CHANCE FOR ANY
THUNDERSTORM ACTIVITY WILL BE FOUND WELL INLAND FROM LAKE ERIE AND
ITS SHADOW...PLACING THE FOCUS FROM ABOUT GENESEE COUNTY TO THE
FINGER LAKES REGION. ALL IN ALL THOUGH...THE DAY WILL BE LARGELY
RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE
LOWER GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH
FAIR DRY WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON
SHOWERS OR THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE
STABILIZING INFLUENCES OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM
         EDT THIS EVENING FOR LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH




000
FXUS61 KBUF 010820
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
420 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND NORTH
TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL PROVIDE
THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A FAIRLY ROBUST MID LEVEL DISTURBANCE TRACKING EAST ACROSS LAKE
ONTARIO (AS OF THE WRITING OF THIS DISCUSSION) PUSHED A COOL
FRONTAL BOUNDARY ACROSS OUR FORECAST AREA OVERNIGHT. THIS RESULTED
IN A FEW SHOWERS AND THUNDERSTORMS...PARTICULARLY OVER THE EASTERN
LAKE ONTARIO REGION WHERE THE CONVECTION INTENSIFIED TO SEVERE
LEVELS. THIS ACTIVITY HAS SINCE WEAKENED AND IS NOW IN THE PROCESS
OF PUSHING EAST ACROSS THE ADIRONDACKS.

AS FOR TODAY...HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL
NOSE NORTHWARDS TO THE LOWER GREAT LAKES. THIS WILL PROVIDE THE
BULK OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER
IMPULSE OF ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR
THIS AFTERNOON AND EVENING. AS OF 08Z...THE SHORTWAVE COULD BE
SEEN IN WV IMAGERY DIGGING ITS WAY SOUTHEASTWARD ACROSS LAKE
SUPERIOR. IT WILL CROSS LAKE ONTARIO LATER THIS AFTERNOON AND
EARLY EVENING...JUST AS OUR AIRMASS REACHES ITS GREATEST DIURNAL
INSTABILITY. SBCAPES WILL APPROACH 1000 J/KG AT THE TIME OF ITS
PASSAGE...BUT WITH A RELATIVELY DRY AIRMASS IN PLACE AND A STRONG
LAKE BREEZE EXTENDING NORTHEAST FROM LAKE ERIE...THE CONVECTION IS
NOT EXPECTED TO BE WIDESPREAD. THE GREATEST CHANCE FOR ANY
THUNDERSTORM ACTIVITY WILL BE FOUND WELL INLAND FROM LAKE ERIE AND
ITS SHADOW...PLACING THE FOCUS FROM ABOUT GENESEE COUNTY TO THE
FINGER LAKES REGION. ALL IN ALL THOUGH...THE DAY WILL BE LARGELY
RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE
MERCURY TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

TONIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY DIE OFF
EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE AFOREMENTIONED
SFC HIGH AS THE DOMINATING WEATHER FEATURE. TEMPERATURES TONIGHT
WILL DROP INTO THE LOWER 60S ACROSS THE LAKE PLAINS WHILE MINS
WILL BE FOUND IN THE MID 50S IN THE COOLER SRN TIER VALLEYS AND
POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ON SUNDAY SURFACE HIGH PRESSURE WILL REMAIN ANCHORED FROM THE
CENTRAL APPALACHIANS TO NEW ENGLAND...WHILE UPSTREAM THE NEXT
SIGNIFICANT SHORTWAVE TROUGH WILL DIG ACROSS THE UPPER GREAT
LAKES...ALONG WITH ITS ATTENDANT COLD FRONT. WITH THE 00Z GUIDANCE
SUITE HAVING UNIVERSALLY SLOWED THE TIMING OF THIS NEXT
SYSTEM...IT NOW APPEARS THAT SUNDAY SHOULD REMAIN MOSTLY IF NOT
ENTIRELY DRY...WITH JUST SOME LOW-END CHANCES OF A
SHOWER/THUNDERSTORM REACHING THE SAINT LAWRENCE VALLEY AND EXTREME
FAR WESTERN NEW YORK BY VERY LATE SUNDAY AFTERNOON/EARLY SUNDAY
EVENING. WITH THE WARM ADVECTION REGIME OUT AHEAD OF THE
APPROACHING SHORTWAVE HELPING TO PUSH 850 MB TEMPS INTO THE +13C
TO +16C RANGE AND A TIGHTENING PRESSURE GRADIENT PROMOTING AN
INCREASING SOUTHWESTERLY BREEZE/CONSEQUENT GOOD MIXING...AFTERNOON
HIGH TEMPERATURES SHOULD MOSTLY RANGE IN THE LOWER TO MID 80S.

DURING THE COURSE OF SUNDAY NIGHT AND MONDAY...THE AFOREMENTIONED
SHORTWAVE TROUGH WILL DIG FURTHER SOUTHEASTWARD INTO THE LOWER
GREAT LAKES...WHILE AT THE SURFACE A PRE-COLD FRONTAL TROUGH WILL
EASE INTO THE REGION SUNDAY NIGHT...FOLLOWED BY THE TRAILING COLD
FRONTAL BOUNDARY ON MONDAY. WHILE THE MAIN OPERATIONAL MODELS
CONTINUE TO EXHIBIT SOME MODEST TIMING DIFFERENCES...IN GENERAL
THE INCREASING MOISTURE AND LARGE-SCALE LIFT ATTENDANT TO THESE
FEATURES WILL BRING AN INCREASED RISK FOR SHOWERS AND
THUNDERSTORMS DURING THIS PERIOD. AT THIS JUNCTURE THE GREATEST
CONVECTIVE POTENTIAL/COVERAGE APPEARS AS IF IT WILL LIKELY FOCUS
ON THE OVERNIGHT SUNDAY NIGHT AND MONDAY TIME FRAME...DURING WHICH
THE LOW LIKELY POPS FROM OUR EXISTING CONTINUITY LOOKED VERY
REASONABLE AND HAVE THUS BEEN MAINTAINED.

WITH RESPECT TO SEVERE POTENTIAL...INSTABILITY LEVELS SHOULD
INITIALLY BE HELD IN CHECK BY THE UNFAVORABLE PORTION OF THE
DIURNAL CYCLE LATER SUNDAY NIGHT THROUGH THE FIRST PART OF MONDAY
MORNING...WHICH SHOULD HELP TO GREATLY LIMIT THE POTENTIAL FOR
STRONGER STORMS THROUGH THAT TIME. THIS COULD HOWEVER CHANGE BY
LATER MONDAY MORNING/AFTERNOON AS RENEWED DIURNAL HEATING MAY LEAD
TO INCREASING INSTABILITY OUT AHEAD OF THE APPROACHING COLD
FRONT...WITH THE EXACT AMOUNT OF DESTABILIZATION WE CAN EXPECT
REMAINING UNCERTAIN AT THIS POINT AND HIGHLY DEPENDENT ON BOTH THE
TIMING OF THE FRONT AND THE AMOUNT OF ANY CLOUD COVER/PRECIP
INITIALLY PRESENT MONDAY MORNING. SHOULD SUFFICIENT
DESTABILIZATION BE REALIZED...ENOUGH DEEP-LAYER SHEAR LOOKS TO BE
IN PLACE TO SUPPORT AT LEAST A LOW CHANCE FOR SOME STRONGER TO
MARGINALLY SEVERE STORMS. IN THEIR NEW DAY 3 CONVECTIVE
OUTLOOK...SPC HAS PLACED MUCH OF OUR REGION IN A MARGINAL RISK FOR
SEVERE STORMS ON MONDAY...AND THIS LOOKS QUITE REASONABLE GIVEN
THE ABOVE FACTORS.

FOLLOWING THE PASSAGE OF THE COLD FRONT...SUBSIDENCE IN ITS WAKE
ALONG WITH THE ARRIVAL OF A SWATH OF SOMEWHAT DRIER AIR SHOULD
LEAD TO PRECIP CHANCES DIMINISHING FROM WEST TO EAST LATER MONDAY
AFTERNOON AND EVENING... WITH MAINLY DRY WEATHER THEN FOLLOWING
FOR THE SECOND HALF OF MONDAY NIGHT.

WITH REGARD TO TEMPERATURES FROM SUNDAY NIGHT ONWARD...LOWS
SUNDAY NIGHT SHOULD RANGE SOLIDLY ABOVE NORMAL OUT AHEAD OF THE
APPROACHING COLD FRONT...WITH READINGS RANGING FROM THE LOWER 60S
ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER/NORTH COUNTRY TO
NEAR 70 ALONG THE LAKESHORES. AFTER THAT...EXPECT READINGS TO
RETURN TO NEAR NORMAL LEVELS FOR THE BALANCE OF THE PERIOD...WITH
DAYTIME HIGHS AVERAGING OUT NEAR 80 ON MONDAY...AND NIGHTTIME LOWS
THEN DROPPING BACK INTO THE UPPER 50S TO LOWER 60S MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
IN THE BIG PICTURE...THE EXTENDED PORTION OF THE FORECAST WILL
FEATURE UPPER LEVEL TROUGHING DIGGING ACROSS THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK...BEFORE GRADUALLY LIFTING OUT INTO THE
CANADIAN MARITIMES THURSDAY AND FRIDAY AND ALLOWING THE LARGE-
SCALE FLOW ACROSS OUR REGION TO TREND MORE QUASI-ZONAL AGAIN BY
THE END OF THE PERIOD. FOR OUR REGION...THIS WILL RESULT IN
TEMPERATURES FALLING BACK TO BELOW NORMAL LEVELS FOR MOST IF NOT
ALL OF THIS PERIOD...WHEN DAILY HIGHS WILL MAINLY BE IN THE LOWER
TO MIDDLE 70S...AND NIGHTTIME LOWS WILL RANGE THROUGH THE 50S.

IN TERMS OF PRECIPITATION CHANCES...THE TREND TOWARD COOLER
WEATHER WILL BE USHERED IN BY THE PASSAGE OF A SECONDARY COLD
FRONT LATER TUESDAY AND TUESDAY NIGHT...WHICH WILL PROBABLY BE
ACCOMPANIED BY ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS AS IT CROSSES OUR REGION. ADDITIONAL SCATTERED
SHOWERS MAY THEN LINGER INTO WEDNESDAY ACROSS THE EASTERN HALF OF
THE AREA IN CONJUNCTION WITH THE PASSAGE OF THE MAIN UPPER LEVEL
TROUGH AXIS AND POSSIBLE LAKE ENHANCEMENT DOWNWIND OF LAKE
ONTARIO...BEFORE INCREASING SURFACE- BASED RIDGING AND DRIER AIR
THEN BRINGS A RETURN TO MAINLY DRY WEATHER FOR BOTH THURSDAY AND
FRIDAY.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE NORTH ACROSS THE
LOWER GREAT LAKES TODAY. WHILE THIS WILL SUPPLY OUR REGION WITH
FAIR DRY WEATHER FOR THE BULK OF THE DAY...A COUPLE AFTERNOON
SHOWERS OR THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE
STABILIZING INFLUENCES OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR TONIGHT AS HIGH PRESSURE
CENTERED TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY...VFR.
SUNDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
MONDAY...VFR TO OCCASIONALLY MVFR WITH SHOWERS AND STORMS LIKELY.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR.

&&

.MARINE...
ANOTHER WEAK TROUGH AND RELATIVELY TIGHT SFC PRESSURE GRADIENT
WILL PRODUCE ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS
TODAY ACROSS THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH
WINDS DROPPING OFF SOME TONIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS AGAIN ON BOTH LAKES LATER
SUNDAY. THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT
INTO MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM
         EDT THIS EVENING FOR LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH





000
FXUS61 KBUF 010619
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
219 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND
NORTH TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A MID LEVEL DISTURBANCE CROSSING SOUTHERN ONTARIO AT 06Z IS
PUSHING A WEAK FRONTAL BOUNDARY ACROSS OUR FORECAST AREA. THESE
FEATURES WILL BE RESPONSIBLE FOR THE SHOWERS AND THUNDERSTORMS THAT
WILL CROSS THE EASTERN LAKE ONTARIO REGION DURING THE REMAINING PRE
DAWN HOURS. OTHERWISE...PARTLY MOONLIT SKIES ARE ANTICIPATED WITH
TEMPERATURES IN THE 60S.

AFTER DAYBREAK...HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL
NOSE NORTHWARDS TO THE LOWER GREAT LAKES. THIS WILL PROVIDE THE BULK
OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER IMPULSE OF
ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR THIS AFTERNOON
AND EVENING. AS OF 06Z...THE SHORTWAVE COULD BE SEEN IN WV IMAGERY
DIGGING ITS WAY SOUTHEASTWARD TOWARDS LAKE SUPERIOR. IT WILL CROSS
LAKE ONTARIO LATER THIS AFTERNOON AND EARLY EVENING...JUST AS OUR
AIRMASS REACHES ITS GREATEST DIURNAL INSTABILITY. SBCAPES WILL
APPROACH 1000 J/KG AT THE TIME OF ITS PASSAGE...BUT WITH A
RELATIVELY DRY AIRMASS IN PLACE...CONVECTION IS NOT EXPECTED TO BE
WIDESPREAD. THE GREATEST CHANCE FOR ANY THUNDERSTORM ACTIVITY WILL
BE FOUND WELL INLAND FROM LAKE ERIE AND ITS SHADOW...PLACING THE
FOCUS FROM ABOUT GENESEE COUNTY TO THE FINGER LAKES REGION. ALL IN
ALL THOUGH...THE DAY WILL BE LARGELY RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE MERCURY
TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

FOR THE UPCOMING NIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY
DIE OFF EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE
AFOREMENTIONED SFC HIGH AS THE DOMINATING WEATHER FEATURE.
TEMPERATURES TONIGHT WILL DROP INTO THE LOWER 60S ACROSS THE LAKE
PLAINS WHILE MINS WILL BE FOUND IN THE MID 50S IN THE COOLER SRN
TIER VALLEYS AND POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE
OVER THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW
PRESSURE NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER
AIR NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS.
DAYTIME INSTABILITY MAY TRIGGER A SHOWER OR
THUNDERSTORM...ESPECIALLY ON LAKE BREEZE BOUNDARIES...BUT LACKING
A GOOD FORCING MECHANISM DONT EXPECT TOO MANY STORMS. SUNDAY WILL
ALSO BE BREEZY AS AREAS DOWNWIND OF THE EASTERN GREAT LAKES ON A
SOUTHWEST WIND MAY GUST 25 TO 30 MPH THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CROSS THE EASTERN LAKE
ONTARIO REGION BETWEEN 06 AND 09Z AS A WEAK FRONTAL BOUNDARY MAKES
ITS WAY THROUGH OUR REGION. OTHERWISE...FAIR VFR CONDITIONS WILL BE
IN PLACE.

LATER THIS SATURDAY...HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE
NORTH ACROSS THE LOWER GREAT LAKES. WHILE THIS WILL SUPPLY OUR
REGION WITH FAIR DRY WEATHER FOR THE BULK OF THE DAY...A COUPLE
AFTERNOON SHOWERS OR THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE
STABILIZING INFLUENCES OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR SATURDAY NIGHT AS HIGH
PRESSURE TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
ANOTHER WEAK TROUGH AND DECENT PRESSURE GRADIENT WILL PRODUCE
ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS ON SATURDAY TO THE
EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM
         EDT THIS EVENING FOR LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...APFFEL/THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...HITCHCOCK/RSH/SMITH




000
FXUS61 KBUF 010619
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
219 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND
NORTH TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A MID LEVEL DISTURBANCE CROSSING SOUTHERN ONTARIO AT 06Z IS
PUSHING A WEAK FRONTAL BOUNDARY ACROSS OUR FORECAST AREA. THESE
FEATURES WILL BE RESPONSIBLE FOR THE SHOWERS AND THUNDERSTORMS THAT
WILL CROSS THE EASTERN LAKE ONTARIO REGION DURING THE REMAINING PRE
DAWN HOURS. OTHERWISE...PARTLY MOONLIT SKIES ARE ANTICIPATED WITH
TEMPERATURES IN THE 60S.

AFTER DAYBREAK...HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL
NOSE NORTHWARDS TO THE LOWER GREAT LAKES. THIS WILL PROVIDE THE BULK
OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER IMPULSE OF
ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR THIS AFTERNOON
AND EVENING. AS OF 06Z...THE SHORTWAVE COULD BE SEEN IN WV IMAGERY
DIGGING ITS WAY SOUTHEASTWARD TOWARDS LAKE SUPERIOR. IT WILL CROSS
LAKE ONTARIO LATER THIS AFTERNOON AND EARLY EVENING...JUST AS OUR
AIRMASS REACHES ITS GREATEST DIURNAL INSTABILITY. SBCAPES WILL
APPROACH 1000 J/KG AT THE TIME OF ITS PASSAGE...BUT WITH A
RELATIVELY DRY AIRMASS IN PLACE...CONVECTION IS NOT EXPECTED TO BE
WIDESPREAD. THE GREATEST CHANCE FOR ANY THUNDERSTORM ACTIVITY WILL
BE FOUND WELL INLAND FROM LAKE ERIE AND ITS SHADOW...PLACING THE
FOCUS FROM ABOUT GENESEE COUNTY TO THE FINGER LAKES REGION. ALL IN
ALL THOUGH...THE DAY WILL BE LARGELY RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE MERCURY
TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

FOR THE UPCOMING NIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY
DIE OFF EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE
AFOREMENTIONED SFC HIGH AS THE DOMINATING WEATHER FEATURE.
TEMPERATURES TONIGHT WILL DROP INTO THE LOWER 60S ACROSS THE LAKE
PLAINS WHILE MINS WILL BE FOUND IN THE MID 50S IN THE COOLER SRN
TIER VALLEYS AND POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE
OVER THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW
PRESSURE NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER
AIR NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS.
DAYTIME INSTABILITY MAY TRIGGER A SHOWER OR
THUNDERSTORM...ESPECIALLY ON LAKE BREEZE BOUNDARIES...BUT LACKING
A GOOD FORCING MECHANISM DONT EXPECT TOO MANY STORMS. SUNDAY WILL
ALSO BE BREEZY AS AREAS DOWNWIND OF THE EASTERN GREAT LAKES ON A
SOUTHWEST WIND MAY GUST 25 TO 30 MPH THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CROSS THE EASTERN LAKE
ONTARIO REGION BETWEEN 06 AND 09Z AS A WEAK FRONTAL BOUNDARY MAKES
ITS WAY THROUGH OUR REGION. OTHERWISE...FAIR VFR CONDITIONS WILL BE
IN PLACE.

LATER THIS SATURDAY...HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE
NORTH ACROSS THE LOWER GREAT LAKES. WHILE THIS WILL SUPPLY OUR
REGION WITH FAIR DRY WEATHER FOR THE BULK OF THE DAY...A COUPLE
AFTERNOON SHOWERS OR THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE
STABILIZING INFLUENCES OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR SATURDAY NIGHT AS HIGH
PRESSURE TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
ANOTHER WEAK TROUGH AND DECENT PRESSURE GRADIENT WILL PRODUCE
ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS ON SATURDAY TO THE
EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM
         EDT THIS EVENING FOR LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...APFFEL/THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...HITCHCOCK/RSH/SMITH





000
FXUS61 KBUF 010619
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
219 AM EDT SAT AUG 1 2015

.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY THIS MORNING WILL EXTEND
NORTH TO THE LOWER GREAT LAKES THIS AFTERNOON. WHILE THIS WILL
PROVIDE THE BULK OF OUR REGION WITH FAIR DRY WEATHER THROUGH THE
WEEKEND...A ROBUST MID LEVEL DISTURBANCE COULD TOUCH OFF A SHOWER
OR THUNDERSTORM THIS AFTERNOON OR EVENING. A COLD FRONT WILL THEN
BRING A HIGHER CHANCE FOR SHOWERS AND STORMS TO THE REGION SUNDAY
NIGHT AND MONDAY. THIS FRONT WILL USHER IN A MUCH COOLER AIRMASS
FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A MID LEVEL DISTURBANCE CROSSING SOUTHERN ONTARIO AT 06Z IS
PUSHING A WEAK FRONTAL BOUNDARY ACROSS OUR FORECAST AREA. THESE
FEATURES WILL BE RESPONSIBLE FOR THE SHOWERS AND THUNDERSTORMS THAT
WILL CROSS THE EASTERN LAKE ONTARIO REGION DURING THE REMAINING PRE
DAWN HOURS. OTHERWISE...PARTLY MOONLIT SKIES ARE ANTICIPATED WITH
TEMPERATURES IN THE 60S.

AFTER DAYBREAK...HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL
NOSE NORTHWARDS TO THE LOWER GREAT LAKES. THIS WILL PROVIDE THE BULK
OF OUR REGION WITH FAIR DRY WEATHER...ALTHOUGH ANOTHER IMPULSE OF
ENERGY IN THE MID LEVELS WILL HAVE TO BE WATCHED FOR THIS AFTERNOON
AND EVENING. AS OF 06Z...THE SHORTWAVE COULD BE SEEN IN WV IMAGERY
DIGGING ITS WAY SOUTHEASTWARD TOWARDS LAKE SUPERIOR. IT WILL CROSS
LAKE ONTARIO LATER THIS AFTERNOON AND EARLY EVENING...JUST AS OUR
AIRMASS REACHES ITS GREATEST DIURNAL INSTABILITY. SBCAPES WILL
APPROACH 1000 J/KG AT THE TIME OF ITS PASSAGE...BUT WITH A
RELATIVELY DRY AIRMASS IN PLACE...CONVECTION IS NOT EXPECTED TO BE
WIDESPREAD. THE GREATEST CHANCE FOR ANY THUNDERSTORM ACTIVITY WILL
BE FOUND WELL INLAND FROM LAKE ERIE AND ITS SHADOW...PLACING THE
FOCUS FROM ABOUT GENESEE COUNTY TO THE FINGER LAKES REGION. ALL IN
ALL THOUGH...THE DAY WILL BE LARGELY RAIN FREE.

TEMPERATURES TODAY WILL BE A FEW DEGREES LOWER THAN THOSE FROM
FRIDAY...AS H85 TEMPS AVERAGING 12C WILL ONLY ENCOURAGE THE MERCURY
TO CLIMB INTO THE UPPER 70S TO NEAR 80 IN MOST LOCATIONS.

FOR THE UPCOMING NIGHT...ANY LATE AFTERNOON CONVECTION WILL QUICKLY
DIE OFF EARLY IN THE EVENING...LEAVING SUBSIDENCE FROM THE
AFOREMENTIONED SFC HIGH AS THE DOMINATING WEATHER FEATURE.
TEMPERATURES TONIGHT WILL DROP INTO THE LOWER 60S ACROSS THE LAKE
PLAINS WHILE MINS WILL BE FOUND IN THE MID 50S IN THE COOLER SRN
TIER VALLEYS AND POSSIBLY THE FOOTHILLS OF THE ADIRONDACKS.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE
OVER THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW
PRESSURE NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER
AIR NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS.
DAYTIME INSTABILITY MAY TRIGGER A SHOWER OR
THUNDERSTORM...ESPECIALLY ON LAKE BREEZE BOUNDARIES...BUT LACKING
A GOOD FORCING MECHANISM DONT EXPECT TOO MANY STORMS. SUNDAY WILL
ALSO BE BREEZY AS AREAS DOWNWIND OF THE EASTERN GREAT LAKES ON A
SOUTHWEST WIND MAY GUST 25 TO 30 MPH THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CROSS THE EASTERN LAKE
ONTARIO REGION BETWEEN 06 AND 09Z AS A WEAK FRONTAL BOUNDARY MAKES
ITS WAY THROUGH OUR REGION. OTHERWISE...FAIR VFR CONDITIONS WILL BE
IN PLACE.

LATER THIS SATURDAY...HIGH PRESSURE OVER THE OHIO VALLEY WILL NOSE
NORTH ACROSS THE LOWER GREAT LAKES. WHILE THIS WILL SUPPLY OUR
REGION WITH FAIR DRY WEATHER FOR THE BULK OF THE DAY...A COUPLE
AFTERNOON SHOWERS OR THUNDERSTORMS WILL BE POSSIBLE AWAY FROM THE
STABILIZING INFLUENCES OF THE LAKES.

VFR CONDITIONS ARE THEN ANTICIPATED FOR SATURDAY NIGHT AS HIGH
PRESSURE TO OUR SOUTH SHOULD REMAIN IN CONTROL.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
ANOTHER WEAK TROUGH AND DECENT PRESSURE GRADIENT WILL PRODUCE
ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS ON SATURDAY TO THE
EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM EDT
         THIS EVENING FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM
         EDT THIS EVENING FOR LOZ043>045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...APFFEL/THOMAS
LONG TERM...THOMAS
AVIATION...RSH
MARINE...HITCHCOCK/RSH/SMITH




000
FXUS61 KBUF 010302
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1102 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION OVERNIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION OVERNIGHT. RADAR MOSAIC AT 11PM
SHOWS WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WORKING
ACROSS WESTERN AND NORTH-CENTRAL NEW YORK. THE BACK EDGE IS SHOWING
UP NEAR MISSISSAUGA ONTARIO ALONG THE LEADING EDGE OF THE SURFACE
TROUGH. AS THE TROUGH PASSES WEST TO EAST ACROSS THE FORECAST EXPECT
SHOWER AND THUNDERSTORM ACTIVITY TO ALSO TAPER OFF.

PARTLY SUNNY SKIES ARE THEN EXPECTED SATURDAY MORNING BEFORE ANOTHER
WEAK TROUGH IS EXPECTED TO CROSS THE AREA DURING THE AFTERNOON.
TEMPERATURES WILL BE COOLER ALOFT ON SATURDAY...AND THE SUBSEQUENT
STEEP LOW/MID LEVEL LAPSE RATES AND SUFFICIENT LOW LEVEL MOISTURE
WILL PRODUCE A WIDESPREAD AREA OF CONGESTED CUMULUS DURING THE LATE
MORNING AND AFTERNOON. MOST AREAS INLAND FROM THE LAKES WILL TREND
TOWARDS MOSTLY CLOUDY SKIES WITH WIDELY SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS DURING THE AFTERNOON IN RESPONSE TO LAKE
BREEZE CONVERGENCE AND WEAK ASCENT FROM THE APPROACHING MID LEVEL
TROUGH. STABLE LAKE SHADOWS WILL KEEP AREAS EAST OF BOTH LAKES
SUNNIER AND DRIER THROUGH AT LEAST MID AFTERNOON...ALTHOUGH THE
APPROACH OF THE MID LEVEL TROUGH MAY FORCE A SHOWER OR TWO THROUGH
THE STABLE LAKE SHADOWS BY LATE AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
NO CHANGES TO THE SHORT TERM FORECAST THIS EVENING.

PREVIOUS DISCUSSION...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OBSERVED ON
RADAR AT 11PM SHIFTING ACROSS WESTERN AND NORTH-CENTRAL NEW YORK AS
A WEAK TROUGH CROSSES THE EASTERN GREAT LAKES. ANY HEAVIER SHOWERS
MAY CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL
PREVAIL THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END OVERNIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
ANOTHER WEAK TROUGH AND DECENT PRESSURE GRADIENT WILL
BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS ON SATURDAY
TO THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...APFFEL/THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 010302
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1102 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION OVERNIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION OVERNIGHT. RADAR MOSAIC AT 11PM
SHOWS WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WORKING
ACROSS WESTERN AND NORTH-CENTRAL NEW YORK. THE BACK EDGE IS SHOWING
UP NEAR MISSISSAUGA ONTARIO ALONG THE LEADING EDGE OF THE SURFACE
TROUGH. AS THE TROUGH PASSES WEST TO EAST ACROSS THE FORECAST EXPECT
SHOWER AND THUNDERSTORM ACTIVITY TO ALSO TAPER OFF.

PARTLY SUNNY SKIES ARE THEN EXPECTED SATURDAY MORNING BEFORE ANOTHER
WEAK TROUGH IS EXPECTED TO CROSS THE AREA DURING THE AFTERNOON.
TEMPERATURES WILL BE COOLER ALOFT ON SATURDAY...AND THE SUBSEQUENT
STEEP LOW/MID LEVEL LAPSE RATES AND SUFFICIENT LOW LEVEL MOISTURE
WILL PRODUCE A WIDESPREAD AREA OF CONGESTED CUMULUS DURING THE LATE
MORNING AND AFTERNOON. MOST AREAS INLAND FROM THE LAKES WILL TREND
TOWARDS MOSTLY CLOUDY SKIES WITH WIDELY SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS DURING THE AFTERNOON IN RESPONSE TO LAKE
BREEZE CONVERGENCE AND WEAK ASCENT FROM THE APPROACHING MID LEVEL
TROUGH. STABLE LAKE SHADOWS WILL KEEP AREAS EAST OF BOTH LAKES
SUNNIER AND DRIER THROUGH AT LEAST MID AFTERNOON...ALTHOUGH THE
APPROACH OF THE MID LEVEL TROUGH MAY FORCE A SHOWER OR TWO THROUGH
THE STABLE LAKE SHADOWS BY LATE AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
NO CHANGES TO THE SHORT TERM FORECAST THIS EVENING.

PREVIOUS DISCUSSION...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OBSERVED ON
RADAR AT 11PM SHIFTING ACROSS WESTERN AND NORTH-CENTRAL NEW YORK AS
A WEAK TROUGH CROSSES THE EASTERN GREAT LAKES. ANY HEAVIER SHOWERS
MAY CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL
PREVAIL THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END OVERNIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
ANOTHER WEAK TROUGH AND DECENT PRESSURE GRADIENT WILL
BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS ON SATURDAY
TO THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...APFFEL/THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 010302
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1102 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION OVERNIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION OVERNIGHT. RADAR MOSAIC AT 11PM
SHOWS WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WORKING
ACROSS WESTERN AND NORTH-CENTRAL NEW YORK. THE BACK EDGE IS SHOWING
UP NEAR MISSISSAUGA ONTARIO ALONG THE LEADING EDGE OF THE SURFACE
TROUGH. AS THE TROUGH PASSES WEST TO EAST ACROSS THE FORECAST EXPECT
SHOWER AND THUNDERSTORM ACTIVITY TO ALSO TAPER OFF.

PARTLY SUNNY SKIES ARE THEN EXPECTED SATURDAY MORNING BEFORE ANOTHER
WEAK TROUGH IS EXPECTED TO CROSS THE AREA DURING THE AFTERNOON.
TEMPERATURES WILL BE COOLER ALOFT ON SATURDAY...AND THE SUBSEQUENT
STEEP LOW/MID LEVEL LAPSE RATES AND SUFFICIENT LOW LEVEL MOISTURE
WILL PRODUCE A WIDESPREAD AREA OF CONGESTED CUMULUS DURING THE LATE
MORNING AND AFTERNOON. MOST AREAS INLAND FROM THE LAKES WILL TREND
TOWARDS MOSTLY CLOUDY SKIES WITH WIDELY SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS DURING THE AFTERNOON IN RESPONSE TO LAKE
BREEZE CONVERGENCE AND WEAK ASCENT FROM THE APPROACHING MID LEVEL
TROUGH. STABLE LAKE SHADOWS WILL KEEP AREAS EAST OF BOTH LAKES
SUNNIER AND DRIER THROUGH AT LEAST MID AFTERNOON...ALTHOUGH THE
APPROACH OF THE MID LEVEL TROUGH MAY FORCE A SHOWER OR TWO THROUGH
THE STABLE LAKE SHADOWS BY LATE AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
NO CHANGES TO THE SHORT TERM FORECAST THIS EVENING.

PREVIOUS DISCUSSION...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OBSERVED ON
RADAR AT 11PM SHIFTING ACROSS WESTERN AND NORTH-CENTRAL NEW YORK AS
A WEAK TROUGH CROSSES THE EASTERN GREAT LAKES. ANY HEAVIER SHOWERS
MAY CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL
PREVAIL THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END OVERNIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
ANOTHER WEAK TROUGH AND DECENT PRESSURE GRADIENT WILL
BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY CONDITIONS ON SATURDAY
TO THE EASTERN ENDS OF BOTH LAKES ERIE AND ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...APFFEL/THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 010011
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
811 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT. THE STRONGER LARGE
SCALE SUPPORT IN THE FORM OF DPVA AND HEIGHT FALLS WILL REMAIN WELL
NORTH OF THE AREA ACROSS QUEBEC...WITH THE TRAILING LOW LEVEL TROUGH
FEATURING RELATIVELY WEAK CONVERGENCE AND MOISTURE POOLING. THIS
MATCHES WELL WITH THE RADAR MOSAIC AT 8PM SHOWING WIDELY SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WORKING ACROSS THE EASTERN GREAT
LAKES. THESE WIDELY SCATTERED SHOWERS AND ISOLATED STORMS WILL CROSS
WESTERN AND NORTH-CENTRAL NY THROUGH THE EVENING HOURS TAPERING OFF
WEST TO EAST AFTER MIDNIGHT AS THE TROUGH SHIFTS EAST. GIVEN THE
WEAK FORCING AND MARGINAL INSTABILITY EXPECT ANY STORMS TO REMAIN
WEAK...ALTHOUGH A FEW ISOLATED DOWNPOURS ARE POSSIBLE.

ANY SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST BEFORE DAYBREAK
WITH MOST AREAS SEEING AT LEAST PARTIAL CLEARING BY SATURDAY
MORNING. THE CLEARING WILL BE SHORT LIVED AS ANOTHER WEAK TROUGH
CROSSES THE AREA SATURDAY AFTERNOON. TEMPERATURES WILL BE COOLER
ALOFT ON SATURDAY...AND THE SUBSEQUENT STEEP LOW/MID LEVEL LAPSE
RATES AND SUFFICIENT LOW LEVEL MOISTURE WILL PRODUCE A WIDESPREAD
AREA OF CONGESTED CUMULUS DURING THE LATE MORNING AND AFTERNOON.
MOST AREAS INLAND FROM THE LAKES WILL TREND TOWARDS MOSTLY CLOUDY
SKIES WITH WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
DURING THE AFTERNOON IN RESPONSE TO LAKE BREEZE CONVERGENCE AND WEAK
ASCENT FROM THE APPROACHING MID LEVEL TROUGH. STABLE LAKE SHADOWS
WILL KEEP AREAS EAST OF BOTH LAKES SUNNIER AND DRIER THROUGH AT
LEAST MID AFTERNOON...ALTHOUGH THE APPROACH OF THE MID LEVEL TROUGH
MAY FORCE A SHOWER OR TWO THROUGH THE STABLE LAKE SHADOWS BY LATE
AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS OBSERVED ON RADAR AT 8PM WILL SHIFT ACROSS
WESTERN AND NORTH-CENTRAL NEW YORK THIS EVENING AS A WEAK TROUGH
CROSSES THE EASTERN GREAT LAKES. THE COVERAGE OF THIS ACTIVITY LOOKS
TO REMAIN ON THE SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH
QUALIFIERS AT THE TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY
CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL
THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE INTO THIS EVENING ON LAKE
ERIE BEFORE DIMINISHING OVERNIGHT. ANOTHER WEAK TROUGH AND DECENT
PRESSURE GRADIENT WILL BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY
CONDITIONS ON SATURDAY TO THE EASTERN ENDS OF BOTH LAKES ERIE AND
ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 010011
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
811 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT. THE STRONGER LARGE
SCALE SUPPORT IN THE FORM OF DPVA AND HEIGHT FALLS WILL REMAIN WELL
NORTH OF THE AREA ACROSS QUEBEC...WITH THE TRAILING LOW LEVEL TROUGH
FEATURING RELATIVELY WEAK CONVERGENCE AND MOISTURE POOLING. THIS
MATCHES WELL WITH THE RADAR MOSAIC AT 8PM SHOWING WIDELY SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WORKING ACROSS THE EASTERN GREAT
LAKES. THESE WIDELY SCATTERED SHOWERS AND ISOLATED STORMS WILL CROSS
WESTERN AND NORTH-CENTRAL NY THROUGH THE EVENING HOURS TAPERING OFF
WEST TO EAST AFTER MIDNIGHT AS THE TROUGH SHIFTS EAST. GIVEN THE
WEAK FORCING AND MARGINAL INSTABILITY EXPECT ANY STORMS TO REMAIN
WEAK...ALTHOUGH A FEW ISOLATED DOWNPOURS ARE POSSIBLE.

ANY SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST BEFORE DAYBREAK
WITH MOST AREAS SEEING AT LEAST PARTIAL CLEARING BY SATURDAY
MORNING. THE CLEARING WILL BE SHORT LIVED AS ANOTHER WEAK TROUGH
CROSSES THE AREA SATURDAY AFTERNOON. TEMPERATURES WILL BE COOLER
ALOFT ON SATURDAY...AND THE SUBSEQUENT STEEP LOW/MID LEVEL LAPSE
RATES AND SUFFICIENT LOW LEVEL MOISTURE WILL PRODUCE A WIDESPREAD
AREA OF CONGESTED CUMULUS DURING THE LATE MORNING AND AFTERNOON.
MOST AREAS INLAND FROM THE LAKES WILL TREND TOWARDS MOSTLY CLOUDY
SKIES WITH WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
DURING THE AFTERNOON IN RESPONSE TO LAKE BREEZE CONVERGENCE AND WEAK
ASCENT FROM THE APPROACHING MID LEVEL TROUGH. STABLE LAKE SHADOWS
WILL KEEP AREAS EAST OF BOTH LAKES SUNNIER AND DRIER THROUGH AT
LEAST MID AFTERNOON...ALTHOUGH THE APPROACH OF THE MID LEVEL TROUGH
MAY FORCE A SHOWER OR TWO THROUGH THE STABLE LAKE SHADOWS BY LATE
AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS OBSERVED ON RADAR AT 8PM WILL SHIFT ACROSS
WESTERN AND NORTH-CENTRAL NEW YORK THIS EVENING AS A WEAK TROUGH
CROSSES THE EASTERN GREAT LAKES. THE COVERAGE OF THIS ACTIVITY LOOKS
TO REMAIN ON THE SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH
QUALIFIERS AT THE TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY
CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL
THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE INTO THIS EVENING ON LAKE
ERIE BEFORE DIMINISHING OVERNIGHT. ANOTHER WEAK TROUGH AND DECENT
PRESSURE GRADIENT WILL BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY
CONDITIONS ON SATURDAY TO THE EASTERN ENDS OF BOTH LAKES ERIE AND
ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 010011
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
811 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT. THE STRONGER LARGE
SCALE SUPPORT IN THE FORM OF DPVA AND HEIGHT FALLS WILL REMAIN WELL
NORTH OF THE AREA ACROSS QUEBEC...WITH THE TRAILING LOW LEVEL TROUGH
FEATURING RELATIVELY WEAK CONVERGENCE AND MOISTURE POOLING. THIS
MATCHES WELL WITH THE RADAR MOSAIC AT 8PM SHOWING WIDELY SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WORKING ACROSS THE EASTERN GREAT
LAKES. THESE WIDELY SCATTERED SHOWERS AND ISOLATED STORMS WILL CROSS
WESTERN AND NORTH-CENTRAL NY THROUGH THE EVENING HOURS TAPERING OFF
WEST TO EAST AFTER MIDNIGHT AS THE TROUGH SHIFTS EAST. GIVEN THE
WEAK FORCING AND MARGINAL INSTABILITY EXPECT ANY STORMS TO REMAIN
WEAK...ALTHOUGH A FEW ISOLATED DOWNPOURS ARE POSSIBLE.

ANY SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST BEFORE DAYBREAK
WITH MOST AREAS SEEING AT LEAST PARTIAL CLEARING BY SATURDAY
MORNING. THE CLEARING WILL BE SHORT LIVED AS ANOTHER WEAK TROUGH
CROSSES THE AREA SATURDAY AFTERNOON. TEMPERATURES WILL BE COOLER
ALOFT ON SATURDAY...AND THE SUBSEQUENT STEEP LOW/MID LEVEL LAPSE
RATES AND SUFFICIENT LOW LEVEL MOISTURE WILL PRODUCE A WIDESPREAD
AREA OF CONGESTED CUMULUS DURING THE LATE MORNING AND AFTERNOON.
MOST AREAS INLAND FROM THE LAKES WILL TREND TOWARDS MOSTLY CLOUDY
SKIES WITH WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
DURING THE AFTERNOON IN RESPONSE TO LAKE BREEZE CONVERGENCE AND WEAK
ASCENT FROM THE APPROACHING MID LEVEL TROUGH. STABLE LAKE SHADOWS
WILL KEEP AREAS EAST OF BOTH LAKES SUNNIER AND DRIER THROUGH AT
LEAST MID AFTERNOON...ALTHOUGH THE APPROACH OF THE MID LEVEL TROUGH
MAY FORCE A SHOWER OR TWO THROUGH THE STABLE LAKE SHADOWS BY LATE
AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS OBSERVED ON RADAR AT 8PM WILL SHIFT ACROSS
WESTERN AND NORTH-CENTRAL NEW YORK THIS EVENING AS A WEAK TROUGH
CROSSES THE EASTERN GREAT LAKES. THE COVERAGE OF THIS ACTIVITY LOOKS
TO REMAIN ON THE SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH
QUALIFIERS AT THE TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY
CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL
THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE INTO THIS EVENING ON LAKE
ERIE BEFORE DIMINISHING OVERNIGHT. ANOTHER WEAK TROUGH AND DECENT
PRESSURE GRADIENT WILL BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY
CONDITIONS ON SATURDAY TO THE EASTERN ENDS OF BOTH LAKES ERIE AND
ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH





000
FXUS61 KBUF 010011
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
811 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT. THE STRONGER LARGE
SCALE SUPPORT IN THE FORM OF DPVA AND HEIGHT FALLS WILL REMAIN WELL
NORTH OF THE AREA ACROSS QUEBEC...WITH THE TRAILING LOW LEVEL TROUGH
FEATURING RELATIVELY WEAK CONVERGENCE AND MOISTURE POOLING. THIS
MATCHES WELL WITH THE RADAR MOSAIC AT 8PM SHOWING WIDELY SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WORKING ACROSS THE EASTERN GREAT
LAKES. THESE WIDELY SCATTERED SHOWERS AND ISOLATED STORMS WILL CROSS
WESTERN AND NORTH-CENTRAL NY THROUGH THE EVENING HOURS TAPERING OFF
WEST TO EAST AFTER MIDNIGHT AS THE TROUGH SHIFTS EAST. GIVEN THE
WEAK FORCING AND MARGINAL INSTABILITY EXPECT ANY STORMS TO REMAIN
WEAK...ALTHOUGH A FEW ISOLATED DOWNPOURS ARE POSSIBLE.

ANY SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST BEFORE DAYBREAK
WITH MOST AREAS SEEING AT LEAST PARTIAL CLEARING BY SATURDAY
MORNING. THE CLEARING WILL BE SHORT LIVED AS ANOTHER WEAK TROUGH
CROSSES THE AREA SATURDAY AFTERNOON. TEMPERATURES WILL BE COOLER
ALOFT ON SATURDAY...AND THE SUBSEQUENT STEEP LOW/MID LEVEL LAPSE
RATES AND SUFFICIENT LOW LEVEL MOISTURE WILL PRODUCE A WIDESPREAD
AREA OF CONGESTED CUMULUS DURING THE LATE MORNING AND AFTERNOON.
MOST AREAS INLAND FROM THE LAKES WILL TREND TOWARDS MOSTLY CLOUDY
SKIES WITH WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
DURING THE AFTERNOON IN RESPONSE TO LAKE BREEZE CONVERGENCE AND WEAK
ASCENT FROM THE APPROACHING MID LEVEL TROUGH. STABLE LAKE SHADOWS
WILL KEEP AREAS EAST OF BOTH LAKES SUNNIER AND DRIER THROUGH AT
LEAST MID AFTERNOON...ALTHOUGH THE APPROACH OF THE MID LEVEL TROUGH
MAY FORCE A SHOWER OR TWO THROUGH THE STABLE LAKE SHADOWS BY LATE
AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
SATURDAY NIGHT A SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN
UPPER LEVEL LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A
FEW REMAINING SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE
EARLY SATURDAY EVENING...BUT WITH WANING DAYTIME INSTABILITY AND
THE RISING HEIGHTS ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE LONG RANGE MODELS OF THE GFS/ECMWF ARE
IN GOOD AGREEMENT WITH PLACEMENT OF AN UPPER LEVEL LOW OVER
EASTERN CANADA...AND A SECOND UPPER LEVEL LOW NEAR THE BRITISH
COLUMBIA COASTLINE. A RIDGE OF HIGH PRESSURE WILL BE FOUND BETWEEN
THESE TWO UPPER LEVEL LOWS...THOUGH THE RIDGE WILL LIKELY REMAIN
WEAK AND FARTHER WEST ENOUGH TO NOT BE ABLE TO DISLODGE THE UPPER
LEVEL TROUGH OVER EASTERN CANADA. THOUGH THIS UPPER LEVEL TROUGH
WILL RETREAT SOME...ITS GENERAL PRESENCE WILL SPELL AN EXTENDED
PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
WIDELY SCATTERED SHOWERS OBSERVED ON RADAR AT 8PM WILL SHIFT ACROSS
WESTERN AND NORTH-CENTRAL NEW YORK THIS EVENING AS A WEAK TROUGH
CROSSES THE EASTERN GREAT LAKES. THE COVERAGE OF THIS ACTIVITY LOOKS
TO REMAIN ON THE SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH
QUALIFIERS AT THE TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY
CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL
THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE INTO THIS EVENING ON LAKE
ERIE BEFORE DIMINISHING OVERNIGHT. ANOTHER WEAK TROUGH AND DECENT
PRESSURE GRADIENT WILL BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY
CONDITIONS ON SATURDAY TO THE EASTERN ENDS OF BOTH LAKES ERIE AND
ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK/SMITH
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK/SMITH
MARINE...HITCHCOCK/SMITH




000
FXUS61 KBUF 311937
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
337 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
VISIBLE SATELLITE IMAGERY SHOWING BANDS OF AGITATED CUMULUS ALONG
THE EDGES OF THE ENHANCED SOUTHWEST FLOW OFF LAKE ERIE. THE BAND OF
TOWERING CUMULUS FROM NEAR NIAGARA FALLS TO HAMLIN HAS PRODUCED A
FEW SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS SO FAR...AND WILL
CONTINUE TO DO SO THROUGH THE LATE AFTERNOON OR EARLY EVENING WHERE
LOW LEVEL CONVERGENCE IS MAXIMIZED. WELL ESTABLISHED STABLE LAKE
SHADOWS WILL KEEP AREAS EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO
SUNNY THROUGH THE EARLY EVENING INCLUDING THE BUFFALO AND WATERTOWN
AREAS.

A WEAK TROUGH WILL CROSS THE REGION TONIGHT. THE STRONGER LARGE
SCALE SUPPORT IN THE FORM OF DPVA AND HEIGHT FALLS WILL REMAIN WELL
NORTH OF THE AREA ACROSS QUEBEC...WITH THE TRAILING LOW LEVEL TROUGH
FEATURING RELATIVELY WEAK CONVERGENCE AND MOISTURE POOLING. THE
LATEST 12Z MODEL GUIDANCE HAS TRENDED WEAKER WITH THIS FEATURE...
AND COMBINED WITH THE LACK OF ANY ORGANIZED UPSTREAM ACTIVITY WAS
COMPELLED TO BACK OFF SOME ON POPS FOR TONIGHT. THE WEAK TROUGH MAY
BRING A FEW WIDELY SCATTERED SHOWERS AND ISOLATED STORMS TO WESTERN
NY AND THE SAINT LAWRENCE VALLEY BY LATER THIS EVENING...THEN
CROSSING THE REST OF THE AREA DURING THE LATE EVENING AND EARLY
OVERNIGHT. GIVEN THE WEAK FORCING AND MARGINAL INSTABILITY EXPECT
ANY STORMS TO REMAIN WEAK...ALTHOUGH A FEW ISOLATED DOWNPOURS ARE
POSSIBLE.

ANY SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST BEFORE DAYBREAK
WITH MOST AREAS SEEING AT LEAST PARTIAL CLEARING BY SATURDAY
MORNING. THE CLEARING WILL BE SHORT LIVED AS ANOTHER WEAK TROUGH
CROSSES THE AREA SATURDAY AFTERNOON. TEMPERATURES WILL BE COOLER
ALOFT ON SATURDAY...AND THE SUBSEQUENT STEEP LOW/MID LEVEL LAPSE
RATES AND SUFFICIENT LOW LEVEL MOISTURE WILL PRODUCE A WIDESPREAD
AREA OF CONGESTED CUMULUS DURING THE LATE MORNING AND AFTERNOON.
MOST AREAS INLAND FROM THE LAKES WILL TREND TOWARDS MOSTLY CLOUDY
SKIES WITH WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
DURING THE AFTERNOON IN RESPONSE TO LAKE BREEZE CONVERGENCE AND WEAK
ASCENT FROM THE APPROACHING MID LEVEL TROUGH. STABLE LAKE SHADOWS
WILL KEEP AREAS EAST OF BOTH LAKES SUNNIER AND DRIER THROUGH AT
LEAST MID AFTERNOON...ALTHOUGH THE APPROACH OF THE MID LEVEL TROUGH
MAY FORCE A SHOWER OR TWO THROUGH THE STABLE LAKE SHADOWS BY LATE
AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
SATURDAY NIGHT A
SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN UPPER LEVEL
LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A FEW REMAINING
SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE EARLY SATURDAY
EVENING...BUT WITH WANING DAYTIME INSTABILITY AND THE RISING HEIGHTS
ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE
LONG RANGE MODELS OF THE GFS/ECMWF ARE IN GOOD AGREEMENT WITH
PLACEMENT OF AN UPPER LEVEL LOW OVER EASTERN CANADA...AND A SECOND
UPPER LEVEL LOW NEAR THE BRITISH COLUMBIA COASTLINE. A RIDGE OF HIGH
PRESSURE WILL BE FOUND BETWEEN THESE TWO UPPER LEVEL LOWS...THOUGH
THE RIDGE WILL LIKELY REMAIN WEAK AND FARTHER WEST ENOUGH TO NOT BE
ABLE TO DISLODGE THE UPPER LEVEL TROUGH OVER EASTERN CANADA. THOUGH
THIS UPPER LEVEL TROUGH WILL RETREAT SOME...ITS GENERAL PRESENCE
WILL SPELL AN EXTENDED PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
SCT-BKN DIURNAL CUMULUS WILL CONTINUE THROUGH THE AFTERNOON HOURS
ACROSS MUCH OF WESTERN NY ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES WITH BASES IN THE 4-6K FOOT RANGE. STABLE LAKE SHADOWS
ENE OF LAKES ERIE AND ONTARIO WILL KEEP THE KBUF AND KART AREAS
MAINLY CLEAR.

WIDELY SCATTERED CONVECTION WILL CONTINUE TO FORM ALONG THE
CONVERGENCE ZONE OVER THE NIAGARA PENINSULA NEAR KIAG. TONIGHT A
WEAK TROUGH WILL CROSS THE AREA WITH WIDELY SCATTERED SHOWERS AND
STORMS MOVING IN A BROKEN LINE FROM NORTHWEST TO SOUTHEAST ACROSS
THE AREA. THE COVERAGE OF THIS ACTIVITY LOOKS TO REMAIN ON THE
SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH QUALIFIERS AT THE
TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY CONTAIN BRIEF/LOCAL
MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL THE MAJORITY OF THE
TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE INTO THIS EVENING ON LAKE
ERIE BEFORE DIMINISHING OVERNIGHT. ANOTHER WEAK TROUGH AND DECENT
PRESSURE GRADIENT WILL BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY
CONDITIONS ON SATURDAY TO THE EASTERN ENDS OF BOTH LAKES ERIE AND
ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK
MARINE...HITCHCOCK





000
FXUS61 KBUF 311937
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
337 PM EDT FRI JUL 31 2015

.SYNOPSIS...
A WEAK TROUGH WILL CROSS THE REGION TONIGHT WITH WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE AGAIN SATURDAY AFTERNOON AND SUNDAY
AFTERNOON BUT THE VAST MAJORITY OF THE TIME IS EXPECTED TO BE RAIN
FREE. A STRONGER FRONT WILL CROSS THE AREA SUNDAY NIGHT AND MONDAY
WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS FRONT WILL
USHER IN A MUCH COOLER AIRMASS FOR MUCH OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
VISIBLE SATELLITE IMAGERY SHOWING BANDS OF AGITATED CUMULUS ALONG
THE EDGES OF THE ENHANCED SOUTHWEST FLOW OFF LAKE ERIE. THE BAND OF
TOWERING CUMULUS FROM NEAR NIAGARA FALLS TO HAMLIN HAS PRODUCED A
FEW SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS SO FAR...AND WILL
CONTINUE TO DO SO THROUGH THE LATE AFTERNOON OR EARLY EVENING WHERE
LOW LEVEL CONVERGENCE IS MAXIMIZED. WELL ESTABLISHED STABLE LAKE
SHADOWS WILL KEEP AREAS EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO
SUNNY THROUGH THE EARLY EVENING INCLUDING THE BUFFALO AND WATERTOWN
AREAS.

A WEAK TROUGH WILL CROSS THE REGION TONIGHT. THE STRONGER LARGE
SCALE SUPPORT IN THE FORM OF DPVA AND HEIGHT FALLS WILL REMAIN WELL
NORTH OF THE AREA ACROSS QUEBEC...WITH THE TRAILING LOW LEVEL TROUGH
FEATURING RELATIVELY WEAK CONVERGENCE AND MOISTURE POOLING. THE
LATEST 12Z MODEL GUIDANCE HAS TRENDED WEAKER WITH THIS FEATURE...
AND COMBINED WITH THE LACK OF ANY ORGANIZED UPSTREAM ACTIVITY WAS
COMPELLED TO BACK OFF SOME ON POPS FOR TONIGHT. THE WEAK TROUGH MAY
BRING A FEW WIDELY SCATTERED SHOWERS AND ISOLATED STORMS TO WESTERN
NY AND THE SAINT LAWRENCE VALLEY BY LATER THIS EVENING...THEN
CROSSING THE REST OF THE AREA DURING THE LATE EVENING AND EARLY
OVERNIGHT. GIVEN THE WEAK FORCING AND MARGINAL INSTABILITY EXPECT
ANY STORMS TO REMAIN WEAK...ALTHOUGH A FEW ISOLATED DOWNPOURS ARE
POSSIBLE.

ANY SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST BEFORE DAYBREAK
WITH MOST AREAS SEEING AT LEAST PARTIAL CLEARING BY SATURDAY
MORNING. THE CLEARING WILL BE SHORT LIVED AS ANOTHER WEAK TROUGH
CROSSES THE AREA SATURDAY AFTERNOON. TEMPERATURES WILL BE COOLER
ALOFT ON SATURDAY...AND THE SUBSEQUENT STEEP LOW/MID LEVEL LAPSE
RATES AND SUFFICIENT LOW LEVEL MOISTURE WILL PRODUCE A WIDESPREAD
AREA OF CONGESTED CUMULUS DURING THE LATE MORNING AND AFTERNOON.
MOST AREAS INLAND FROM THE LAKES WILL TREND TOWARDS MOSTLY CLOUDY
SKIES WITH WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
DURING THE AFTERNOON IN RESPONSE TO LAKE BREEZE CONVERGENCE AND WEAK
ASCENT FROM THE APPROACHING MID LEVEL TROUGH. STABLE LAKE SHADOWS
WILL KEEP AREAS EAST OF BOTH LAKES SUNNIER AND DRIER THROUGH AT
LEAST MID AFTERNOON...ALTHOUGH THE APPROACH OF THE MID LEVEL TROUGH
MAY FORCE A SHOWER OR TWO THROUGH THE STABLE LAKE SHADOWS BY LATE
AFTERNOON OR EARLY EVENING.

TEMPERATURES WILL BE A LITTLE COOLER ON SATURDAY WITH 850MB TEMPS
AROUND +11C. EXPECT HIGHS IN THE UPPER 70S TO AROUND 80 AT LOWER
ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN. IT WILL BECOME BREEZY
AGAIN EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO WITH GUSTS AROUND
30 MPH DURING THE MIDDAY AND AFTERNOON.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
SATURDAY NIGHT A
SHORTWAVE WILL BE PASSING THROUGH THE BASE OF AN UPPER LEVEL
LOW...SHIFTING THE AXIS OF LOWER HEIGHTS EASTWARD. A FEW REMAINING
SHOWERS OR PERHAPS A THUNDERSTORMS WILL BE POSSIBLE EARLY SATURDAY
EVENING...BUT WITH WANING DAYTIME INSTABILITY AND THE RISING HEIGHTS
ALOFT EXPECT THE BULK OF THE NIGHT TO BE DRY.

SUNDAY WILL START DRY AS SOUTHWEST FLOW IS FOUND OVER THE EASTERN
GREAT LAKES REGION...THIS FLOW BETWEEN AN AREA OF HIGH PRESSURE OVER
THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS...AND LOW PRESSURE
NEAR HUDSON BAY. THIS SOUTHWEST FLOW WILL BRING WARMER AIR
NORTHWARD...ALONG WITH A DEGREE OR TWO RISE IN DEWPOINTS. DAYTIME
INSTABILITY MAY TRIGGER A SHOWER OR THUNDERSTORM...ESPECIALLY ON LAKE
BREEZE BOUNDARIES...BUT LACKING A GOOD FORCING MECHANISM DONT EXPECT
TOO MANY STORMS. SUNDAY WILL ALSO BE BREEZY AS AREAS DOWNWIND OF THE
EASTERN GREAT LAKES ON A SOUTHWEST WIND MAY GUST 25 TO 30 MPH
THROUGH THE AFTERNOON HOURS.

SUNDAY NIGHT ANOTHER SHORTWAVE TROUGH WILL ROUND THE LARGE HUDSON
BAY UPPER LEVEL LOW. THIS SHORTWAVE IS A LITTLE MORE POTENT AND LIFT
FROM THIS FEATURE/NEARING OF AN UPPER LEVEL THERMAL GRADIENT AND
BUILDING MOISTURE AHEAD OF A COLD FRONT WILL BRING INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS LATE OVERNIGHT SUNDAY...ESPECIALLY
OVER FAR NW AREAS OF THE NIAGARA FRONTIER AND THE SAINT LAWRENCE
VALLEY.

TEMPERATURES WILL REMAIN SEASONABLE THROUGH THIS TIME PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
FOR THIS TIME PERIOD THE
LONG RANGE MODELS OF THE GFS/ECMWF ARE IN GOOD AGREEMENT WITH
PLACEMENT OF AN UPPER LEVEL LOW OVER EASTERN CANADA...AND A SECOND
UPPER LEVEL LOW NEAR THE BRITISH COLUMBIA COASTLINE. A RIDGE OF HIGH
PRESSURE WILL BE FOUND BETWEEN THESE TWO UPPER LEVEL LOWS...THOUGH
THE RIDGE WILL LIKELY REMAIN WEAK AND FARTHER WEST ENOUGH TO NOT BE
ABLE TO DISLODGE THE UPPER LEVEL TROUGH OVER EASTERN CANADA. THOUGH
THIS UPPER LEVEL TROUGH WILL RETREAT SOME...ITS GENERAL PRESENCE
WILL SPELL AN EXTENDED PERIOD OF COOL TIME FOR THE NORTHEAST.

MONDAY WILL BE THE LAST OF NEAR-TO SLIGHTLY ABOVE NORMAL DAY
TEMPERATURE WISE AS THE AXIS OF THE UPPER LEVEL TROUGH REMAINS JUST
TO OUR WEST. THROUGH THE DAY THIS AXIS WILL SWING ACROSS THE EASTERN
GREAT LAKES REGION DRIVING A SURFACE COLD FRONT THAT WILL TRIGGER
SHOWERS AND THUNDERSTORMS. THIS ACTIVITY WILL END FROM WEST TO EAST
THROUGH THE OVERNIGHT HOURS AS THE SURFACE COLD FRONT EVENTUALLY
CLEARS THE REGION. THE GFS IS DEPICTING A FAIR AMOUNT OF INSTABILITY
WITH SBCAPE VALUES EDGING OVER 1000 J/KG OVER THE GENESEE VALLEY AND
FINGER LAKES REGION. A 40 KNOT LLJ PRODUCING LOW LEVEL CONVERGENCE
MAY BE ABLE TO ORGANIZE A FEW OF THESE THUNDERSTORMS INTO STRONG
STORMS.

TUESDAY THROUGH FRIDAY WILL BE COOL WITH CHANCES FOR A RAIN SHOWER
EACH DAY. MULTIPLE VORTICITY MAXIMA ROTATING THROUGH THIS UPPER
LEVEL TROUGH...COMBINED WITH DAY TIME INSTABILITY MAY BRING A FEW
SHOWERS TO THE BUFFALO CWA. WITH LAKE TEMPERATURES NOW IN THE +21 TO
+23C RANGE...AND 850 HPA DROPPING DOWN TO +6 TO +10C...THERE MAY
EVEN BE SOME LAKE ENHANCEMENT TO THESE SHOWERS DOWNWIND OF BOTH
LAKES ERIE AND ONTARIO.

HIGHS TUESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 60S TO
LOW-MID 70S...ABOUT 5-10 DEGREES BELOW NORMAL...WHILE OVERNIGHT LOWS
WILL RUN IN THE 50S. SOME WARMING IS POSSIBLE FRIDAY AS THE UPPER
LEVEL LOW RETREATS NORTHWARD SOME AND A WARM FRONT NEARS THE REGION.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
SCT-BKN DIURNAL CUMULUS WILL CONTINUE THROUGH THE AFTERNOON HOURS
ACROSS MUCH OF WESTERN NY ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES WITH BASES IN THE 4-6K FOOT RANGE. STABLE LAKE SHADOWS
ENE OF LAKES ERIE AND ONTARIO WILL KEEP THE KBUF AND KART AREAS
MAINLY CLEAR.

WIDELY SCATTERED CONVECTION WILL CONTINUE TO FORM ALONG THE
CONVERGENCE ZONE OVER THE NIAGARA PENINSULA NEAR KIAG. TONIGHT A
WEAK TROUGH WILL CROSS THE AREA WITH WIDELY SCATTERED SHOWERS AND
STORMS MOVING IN A BROKEN LINE FROM NORTHWEST TO SOUTHEAST ACROSS
THE AREA. THE COVERAGE OF THIS ACTIVITY LOOKS TO REMAIN ON THE
SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH QUALIFIERS AT THE
TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY CONTAIN BRIEF/LOCAL
MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL THE MAJORITY OF THE
TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
MODERATE SOUTHWESTERLIES WILL CONTINUE INTO THIS EVENING ON LAKE
ERIE BEFORE DIMINISHING OVERNIGHT. ANOTHER WEAK TROUGH AND DECENT
PRESSURE GRADIENT WILL BRING ANOTHER ROUND OF SMALL CRAFT ADVISORY
CONDITIONS ON SATURDAY TO THE EASTERN ENDS OF BOTH LAKES ERIE AND
ONTARIO.

THIS SAME BASIC PATTERN WILL CONTINUE THROUGH THE WEEKEND WITH WINDS
DROPPING OFF SOME SATURDAY NIGHT AND EARLY SUNDAY BEFORE INCREASING
TO NEAR SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES LATER SUNDAY.
THE SMALL CRAFT ADVISORY CONDITIONS MAY LAST SUNDAY NIGHT INTO
MONDAY AS A STRONGER COLD FRONT CROSSES THE REGION.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY FROM 1 PM TO 11 PM EDT SATURDAY FOR
         LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 1 PM TO 8 PM EDT SATURDAY FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 10 AM TO 11 PM EDT SATURDAY
         FOR LOZ043>045.

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK
MARINE...HITCHCOCK




000
FXUS61 KBUF 311731
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
131 PM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
VISIBLE SATELLITE IMAGERY SHOWING PLENTY OF DIURNAL CUMULUS
DEVELOPING EARLY THIS AFTERNOON ALONG AND INLAND FROM THE LAKE
BREEZE BOUNDARIES. SKIES MAY BRIEFLY GO MOSTLY CLOUDY ACROSS THE
HIGHER TERRAIN OF THE WESTERN SOUTHERN TIER...BUT THESE CONGESTED
CUMULUS SHOULD SCATTER OUT AGAIN AS THE MEAGER LOW LEVEL MOISTURE
BECOMES DILUTED THROUGH THE MIXED COLUMN. STABLE LAKE SHADOWS WILL
KEEP AREAS ENE OF LAKES ERIE AND ONTARIO INCLUDING BUFFALO AND
WATERTOWN WITH FULL SUNSHINE THROUGH THE AFTERNOON.

FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SCT-BKN DIURNAL CUMULUS WILL CONTINUE THROUGH THE AFTERNOON HOURS
ACROSS MUCH OF WESTERN NY ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES WITH BASES IN THE 4-6K FOOT RANGE. STABLE LAKE SHADOWS
ENE OF LAKES ERIE AND ONTARIO WILL KEEP THE KBUF AND KART AREAS
MAINLY CLEAR.

BY LATE AFTERNOON WIDELY SCATTERED CONVECTION MAY BEGIN TO FORM
ALONG THE CONVERGENCE ZONE OVER THE NIAGARA PENINSULA NEAR KIAG.
TONIGHT A WEAK TROUGH WILL CROSS THE AREA WITH WIDELY SCATTERED
SHOWERS AND STORMS MOVING IN A BROKEN LINE FROM NORTHWEST TO
SOUTHEAST ACROSS THE AREA. THE COVERAGE OF THIS ACTIVITY LOOKS TO
REMAIN ON THE SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH
QUALIFIERS AT THE TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY
CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL
THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL INCREASE THIS AFTERNOON...THEN WILL LINGER
INTO THE EARLY EVENING HOURS. FOR THIS REASON SMALL CRAFT ADVISORIES
REMAIN IN EFFECT FOR LAKE ERIE AND THE BUFFALO HARBOR/NIAGARA RIVER.

WINDS WILL INCREASE AGAIN ON SATURDAY ON BOTH LAKES ERIE AND THE
EAST HALF OF LAKE ONTARIO. ADDITIONAL SMALL CRAFT ADVISORIES MAY BE
NEEDED FOR THIS TIME FRAME.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...HITCHCOCK/JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HITCHCOCK
MARINE...HITCHCOCK/JJR




000
FXUS61 KBUF 311731
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
131 PM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
VISIBLE SATELLITE IMAGERY SHOWING PLENTY OF DIURNAL CUMULUS
DEVELOPING EARLY THIS AFTERNOON ALONG AND INLAND FROM THE LAKE
BREEZE BOUNDARIES. SKIES MAY BRIEFLY GO MOSTLY CLOUDY ACROSS THE
HIGHER TERRAIN OF THE WESTERN SOUTHERN TIER...BUT THESE CONGESTED
CUMULUS SHOULD SCATTER OUT AGAIN AS THE MEAGER LOW LEVEL MOISTURE
BECOMES DILUTED THROUGH THE MIXED COLUMN. STABLE LAKE SHADOWS WILL
KEEP AREAS ENE OF LAKES ERIE AND ONTARIO INCLUDING BUFFALO AND
WATERTOWN WITH FULL SUNSHINE THROUGH THE AFTERNOON.

FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SCT-BKN DIURNAL CUMULUS WILL CONTINUE THROUGH THE AFTERNOON HOURS
ACROSS MUCH OF WESTERN NY ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES WITH BASES IN THE 4-6K FOOT RANGE. STABLE LAKE SHADOWS
ENE OF LAKES ERIE AND ONTARIO WILL KEEP THE KBUF AND KART AREAS
MAINLY CLEAR.

BY LATE AFTERNOON WIDELY SCATTERED CONVECTION MAY BEGIN TO FORM
ALONG THE CONVERGENCE ZONE OVER THE NIAGARA PENINSULA NEAR KIAG.
TONIGHT A WEAK TROUGH WILL CROSS THE AREA WITH WIDELY SCATTERED
SHOWERS AND STORMS MOVING IN A BROKEN LINE FROM NORTHWEST TO
SOUTHEAST ACROSS THE AREA. THE COVERAGE OF THIS ACTIVITY LOOKS TO
REMAIN ON THE SPARSE SIDE...SO FOR NOW HAVE JUST GONE WITH VCSH
QUALIFIERS AT THE TAF SITES. ANY HEAVIER SHOWERS THAT DEVELOP MAY
CONTAIN BRIEF/LOCAL MVFR OR IFR CONDITIONS...BUT VFR WILL PREVAIL
THE MAJORITY OF THE TIME.

ANY SCATTERED CONVECTION WILL END LATE TONIGHT WITH AT LEAST PARTIAL
CLEARING FOR SATURDAY MORNING. EXTENSIVE DIURNAL CUMULUS ARE THEN
EXPECTED TO DEVELOP FROM LATE MORNING THROUGH THE AFTERNOON ON
SATURDAY WITH MOST AREAS GOING BKN BY MIDDAY. STABLE LAKE SHADOWS
WILL KEEP SKIES MORE CLEAR EAST OF BOTH LAKES. WIDELY SCATTERED
SHOWERS AND ISOLATED STORMS WILL DEVELOP DURING THE AFTERNOON MAINLY
ALONG AND INLAND FROM THE LAKE BREEZES...BUT AGAIN COVERAGE SHOULD
REMAIN SPARSE.

OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH A CHANCE OF A FEW LIGHT SHOWERS.
WEDNESDAY...MAINLY VFR WITH A SLIGHT CHANCE OF A LIGHT SHOWER.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL INCREASE THIS AFTERNOON...THEN WILL LINGER
INTO THE EARLY EVENING HOURS. FOR THIS REASON SMALL CRAFT ADVISORIES
REMAIN IN EFFECT FOR LAKE ERIE AND THE BUFFALO HARBOR/NIAGARA RIVER.

WINDS WILL INCREASE AGAIN ON SATURDAY ON BOTH LAKES ERIE AND THE
EAST HALF OF LAKE ONTARIO. ADDITIONAL SMALL CRAFT ADVISORIES MAY BE
NEEDED FOR THIS TIME FRAME.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...HITCHCOCK/JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HITCHCOCK
MARINE...HITCHCOCK/JJR





000
FXUS61 KBUF 311435
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1035 AM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
VISIBLE SATELLITE IMAGERY SHOWING ABUNDANT SUNSHINE ACROSS THE
REGION LATE THIS MORNING WITH JUST ONE SMALL PATCH OF CIRRUS ACROSS
THE NIAGARA FRONTIER AND SOME DIURNAL CUMULUS STARTING TO DEVELOP
ACROSS THE HIGHER TERRAIN EAST OF LAKE ONTARIO. EXPECT NEARLY FULL
SUNSHINE THROUGH AT LEAST MID AFTERNOON BEFORE CUMULUS BEGIN TO
BECOME MORE PREVALENT ALONG AND INLAND FROM THE BOUNDARIES PRODUCED
BY THE GRADIENT ONSHORE FLOW OFF THE LAKES.

FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
VFR WILL PREVAIL TODAY WITH CLEAR SKIES IN MOST AREAS.

LATE THIS AFTERNOON...THE NEXT IN A SERIES OF SHORTWAVE IMPULSES
WILL BEGIN TO IMPINGE UPON THE REGION. COUPLED WITH LIFT FROM A
LAKE BREEZE CONVERGENCE ZONE...THIS COULD TOUCH OF A SHOWER OR
THUNDERSTORM NEAR KIAG. THE SHORTWAVE WILL THEN PUSH DEEPER INTO
OUR REGION TONIGHT...BRINGING MORE GENERAL CHANCES FOR SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS. ANY OF THESE WILL HAVE THE
POTENTIAL TO PRODUCE BRIEF/LOCALIZED REDUCTIONS IN CIG/VSBY...WITH
VFR CONDITIONS OTHERWISE PREVAILING.

OUTLOOK...
SATURDAY THROUGH MONDAY...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL REDEVELOP ON LAKE ERIE THIS AFTERNOON...
THEN WILL LINGER INTO THE EARLY EVENING HOURS. FOR THIS REASON...
A FRESH BATCH OF SMALL CRAFT ADVISORIES HAVE BEEN HOISTED FOR THE
NEARSHORE WATERS OF LAKE ERIE AND THE UPPER NIAGARA RIVER AND
BUFFALO HARBOR...WITH THE START AND END TIMES OF THESE AS OUTLINED
BELOW.

OTHERWISE...WINDS AND WAVES ARE MOSTLY EXPECTED TO REMAIN BELOW
ADVISORY LEVELS THROUGH THE FIRST HALF OF THE WEEKEND...THOUGH
LOCALLY STRONGER WINDS/HIGHER WAVES WILL BE POSSIBLE IN AND NEAR
ANY SHOWERS AND THUNDERSTORMS TONIGHT AND SATURDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
         SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...HITCHCOCK/JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HITCHCOCK/JJR
MARINE...JJR




000
FXUS61 KBUF 311435
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1035 AM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
VISIBLE SATELLITE IMAGERY SHOWING ABUNDANT SUNSHINE ACROSS THE
REGION LATE THIS MORNING WITH JUST ONE SMALL PATCH OF CIRRUS ACROSS
THE NIAGARA FRONTIER AND SOME DIURNAL CUMULUS STARTING TO DEVELOP
ACROSS THE HIGHER TERRAIN EAST OF LAKE ONTARIO. EXPECT NEARLY FULL
SUNSHINE THROUGH AT LEAST MID AFTERNOON BEFORE CUMULUS BEGIN TO
BECOME MORE PREVALENT ALONG AND INLAND FROM THE BOUNDARIES PRODUCED
BY THE GRADIENT ONSHORE FLOW OFF THE LAKES.

FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
VFR WILL PREVAIL TODAY WITH CLEAR SKIES IN MOST AREAS.

LATE THIS AFTERNOON...THE NEXT IN A SERIES OF SHORTWAVE IMPULSES
WILL BEGIN TO IMPINGE UPON THE REGION. COUPLED WITH LIFT FROM A
LAKE BREEZE CONVERGENCE ZONE...THIS COULD TOUCH OF A SHOWER OR
THUNDERSTORM NEAR KIAG. THE SHORTWAVE WILL THEN PUSH DEEPER INTO
OUR REGION TONIGHT...BRINGING MORE GENERAL CHANCES FOR SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS. ANY OF THESE WILL HAVE THE
POTENTIAL TO PRODUCE BRIEF/LOCALIZED REDUCTIONS IN CIG/VSBY...WITH
VFR CONDITIONS OTHERWISE PREVAILING.

OUTLOOK...
SATURDAY THROUGH MONDAY...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL REDEVELOP ON LAKE ERIE THIS AFTERNOON...
THEN WILL LINGER INTO THE EARLY EVENING HOURS. FOR THIS REASON...
A FRESH BATCH OF SMALL CRAFT ADVISORIES HAVE BEEN HOISTED FOR THE
NEARSHORE WATERS OF LAKE ERIE AND THE UPPER NIAGARA RIVER AND
BUFFALO HARBOR...WITH THE START AND END TIMES OF THESE AS OUTLINED
BELOW.

OTHERWISE...WINDS AND WAVES ARE MOSTLY EXPECTED TO REMAIN BELOW
ADVISORY LEVELS THROUGH THE FIRST HALF OF THE WEEKEND...THOUGH
LOCALLY STRONGER WINDS/HIGHER WAVES WILL BE POSSIBLE IN AND NEAR
ANY SHOWERS AND THUNDERSTORMS TONIGHT AND SATURDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
         SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...HITCHCOCK/JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HITCHCOCK/JJR
MARINE...JJR




000
FXUS61 KBUF 311435
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1035 AM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
VISIBLE SATELLITE IMAGERY SHOWING ABUNDANT SUNSHINE ACROSS THE
REGION LATE THIS MORNING WITH JUST ONE SMALL PATCH OF CIRRUS ACROSS
THE NIAGARA FRONTIER AND SOME DIURNAL CUMULUS STARTING TO DEVELOP
ACROSS THE HIGHER TERRAIN EAST OF LAKE ONTARIO. EXPECT NEARLY FULL
SUNSHINE THROUGH AT LEAST MID AFTERNOON BEFORE CUMULUS BEGIN TO
BECOME MORE PREVALENT ALONG AND INLAND FROM THE BOUNDARIES PRODUCED
BY THE GRADIENT ONSHORE FLOW OFF THE LAKES.

FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
VFR WILL PREVAIL TODAY WITH CLEAR SKIES IN MOST AREAS.

LATE THIS AFTERNOON...THE NEXT IN A SERIES OF SHORTWAVE IMPULSES
WILL BEGIN TO IMPINGE UPON THE REGION. COUPLED WITH LIFT FROM A
LAKE BREEZE CONVERGENCE ZONE...THIS COULD TOUCH OF A SHOWER OR
THUNDERSTORM NEAR KIAG. THE SHORTWAVE WILL THEN PUSH DEEPER INTO
OUR REGION TONIGHT...BRINGING MORE GENERAL CHANCES FOR SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS. ANY OF THESE WILL HAVE THE
POTENTIAL TO PRODUCE BRIEF/LOCALIZED REDUCTIONS IN CIG/VSBY...WITH
VFR CONDITIONS OTHERWISE PREVAILING.

OUTLOOK...
SATURDAY THROUGH MONDAY...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL REDEVELOP ON LAKE ERIE THIS AFTERNOON...
THEN WILL LINGER INTO THE EARLY EVENING HOURS. FOR THIS REASON...
A FRESH BATCH OF SMALL CRAFT ADVISORIES HAVE BEEN HOISTED FOR THE
NEARSHORE WATERS OF LAKE ERIE AND THE UPPER NIAGARA RIVER AND
BUFFALO HARBOR...WITH THE START AND END TIMES OF THESE AS OUTLINED
BELOW.

OTHERWISE...WINDS AND WAVES ARE MOSTLY EXPECTED TO REMAIN BELOW
ADVISORY LEVELS THROUGH THE FIRST HALF OF THE WEEKEND...THOUGH
LOCALLY STRONGER WINDS/HIGHER WAVES WILL BE POSSIBLE IN AND NEAR
ANY SHOWERS AND THUNDERSTORMS TONIGHT AND SATURDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
         SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...HITCHCOCK/JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HITCHCOCK/JJR
MARINE...JJR





000
FXUS61 KBUF 311121
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
721 AM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
OUTSIDE OF SOME LIMITED SOUTHERN TIER VALLEY FOG THAT SHOULD
QUICKLY MIX OUT BY MID MORNING...UNLIMITED VFR CONDITIONS WILL
CONTINUE TO PREVAIL FOR MUCH OF TODAY.

LATE THIS AFTERNOON...THE NEXT IN A SERIES OF SHORTWAVE IMPULSES
WILL BEGIN TO IMPINGE UPON THE REGION. COUPLED WITH LIFT FROM A
LAKE BREEZE CONVERGENCE ZONE...THIS COULD TOUCH OF A SHOWER OR
THUNDERSTORM NEAR KIAG. THE SHORTWAVE WILL THEN PUSH DEEPER INTO
OUR REGION TONIGHT...BRINGING MORE GENERAL CHANCES FOR SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS. ANY OF THESE WILL HAVE THE
POTENTIAL TO PRODUCE BRIEF/LOCALIZED REDUCTIONS IN CIG/VSBY...WITH
VFR CONDITIONS OTHERWISE PREVAILING.

OUTLOOK...
SATURDAY THROUGH MONDAY...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL REDEVELOP ON LAKE ERIE THIS AFTERNOON...
THEN WILL LINGER INTO THE EARLY EVENING HOURS. FOR THIS REASON...
A FRESH BATCH OF SMALL CRAFT ADVISORIES HAVE BEEN HOISTED FOR THE
NEARSHORE WATERS OF LAKE ERIE AND THE UPPER NIAGARA RIVER AND
BUFFALO HARBOR...WITH THE START AND END TIMES OF THESE AS OUTLINED
BELOW.

OTHERWISE...WINDS AND WAVES ARE MOSTLY EXPECTED TO REMAIN BELOW
ADVISORY LEVELS THROUGH THE FIRST HALF OF THE WEEKEND...THOUGH
LOCALLY STRONGER WINDS/HIGHER WAVES WILL BE POSSIBLE IN AND NEAR
ANY SHOWERS AND THUNDERSTORMS TONIGHT AND SATURDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
         SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...JJR
MARINE...JJR




000
FXUS61 KBUF 311121
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
721 AM EDT FRI JUL 31 2015

.SYNOPSIS...
HIGH PRESSURE RIDGED FROM THE OHIO VALLEY INTO NEW YORK STATE
WILL KEEP DRY AND QUIET WEATHER ACROSS OUR REGION THROUGH MOST OF
TODAY. A NUMBER OF DISTURBANCES PASSING THROUGH A BROAD UPPER
LEVEL TROUGH WILL THEN BRING PERIODIC OPPORTUNITIES FOR SCATTERED
SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON AND EVENING
ONWARD INTO EARLY NEXT WEEK...THOUGH MUCH OF THE TIME WILL STILL
BE RAIN FREE.

&&

.NEAR TERM /THROUGH TONIGHT/...
FOR MUCH OF TODAY...OUR REGION WILL REMAIN UNDER THE INFLUENCE OF
HIGH PRESSURE AND DRY AIR RIDGED FROM THE OHIO VALLEY INTO NEW
YORK STATE. THIS WILL RESULT IN FAIR/DRY WEATHER AND MOSTLY SUNNY
SKIES PERSISTING THROUGH THE BULK OF THE DAY...WITH 850 MB TEMPS
OF +14C TO +16C SUPPORTING WIDESPREAD HIGHS IN THE LOWER TO MID
80S. COUPLED WITH DEWPOINTS RANGING FROM THE MID 50S TO AROUND 60
AND A DECENT BREEZE...THIS WILL RESULT IN A PLEASANTLY WARM LAST
DAY OF JULY.

LATE THIS AFTERNOON AND TONIGHT...THE NEXT IN A SERIES OF
SHORTWAVE IMPULSES WILL ROUND THE BASE OF THE DEEPENING LARGE-
SCALE UPPER TROUGH ACROSS THE GREAT LAKES AND NORTHEAST...AND IN
THE PROCESS WILL PUSH INTO OUR REGION IN CONCERT WITH ITS
ATTENDANT WEAK SURFACE REFLECTION. AS THESE FEATURES BEGIN TO
IMPINGE UPON OUR AREA LATE THIS AFTERNOON...INCREASING
LIFT/MOISTURE ASSOCIATED WITH BOTH THESE AND A LAKE BREEZE
CONVERGENCE ZONE COULD TOUCH OFF A SHOWER/THUNDERSTORM OR TWO
ACROSS NIAGARA AND ORLEANS COUNTIES...FOR WHICH SOME LOW CHANCE
POPS REMAIN IN PLAY. BETTER AND MORE GENERAL OPPORTUNITIES FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL THEN FOLLOW
FOR TONIGHT AS THE SHORTWAVE DIGS FURTHER INTO OUR REGION...WITH
CONVECTIVE COVERAGE MOST LIKELY TO PEAK DURING THE LATE EVENING
AND EARLY OVERNIGHT HOURS...THEN DIMINISH OVERNIGHT. AS FOR
TEMPS...OVERNIGHT LOWS ARE AGAIN EXPECTED TO RANGE FROM THE UPPER
50S ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER AND NORTH
COUNTRY TO THE LOWER AND MID 60S ELSEWHERE...WITH THE WARMEST
OVERALL TEMPS FOUND ALONG THE IMMEDIATE LAKESHORES.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A SOMEWHAT AMPLIFIED UPPER LEVEL PATTERN WILL BE IN PLACE OVER
NORTH AMERICA DURING THIS PERIOD. BROAD TROUGHINESS OVER THE GREAT
LAKES WILL BE ANCHORED BY AN ANOMALOUSLY DEEP CLOSED LOW OVER
JAMES BAY... WHILE A STRONG SUB-TROPICAL RIDGE WILL BE CENTERED
OVER NEW MEXICO. THIS WILL KEEP OPPRESSIVE SUMMER HEAT OUT WEST
WHILE OUR REGION WILL EXPERIENCE TEMPERATURES THAT WILL AVERAGE
WITHIN A COUPLE DEGREES OF NORMAL.

IN TERMS OF RAINFALL...IMPULSES TRACKING SOUTHEAST FROM THE
CANADIAN PRAIRIES AND UPPER GREAT LAKES WILL BE CONDUCIVE FOR
PERIODIC SHOWER AND THUNDERSTORM ACTIVITY...BUT THE BULK OF THE
PERIOD WILL BE PCPN FREE. THE DEEP CYCLONIC FLOW WILL ESSENTIALLY
CUT OFF ANY GULF MOISTURE...AND WITHOUT ANY ORGANIZED SFC
FEATURES...PCPN WILL BE SCATTERED IN NATURE WITH GENERAL
INSIGNIFICANT QPF. THIS IS IMPORTANT TO NOTE AS PARTS OF WRN NEW
YORK HAVE RECEIVED LITTLE RAINFALL OVER THE PAST TWO WEEKS.

GETTING TO THE DETAILS... WHILE SATURDAY WILL BE LARGELY DRY
ACROSS THE REGION...A SHORTWAVE WILL TRACK SOUTHEAST FROM LAKE
HURON DURING THE MORNING HOURS AND CROSS TO OUR NORTH DURING THE
MIDDAY AND AFTERNOON. GIVEN THE DISCREPANCIES BETWEEN THE GUIDANCE
PACKAGES...THERE IS RELATIVELY LOW CONFIDENCE WITH THE TIMING OF
THIS FEATURE. THIS IS IMPORTANT IN THAT A SLOWER PASSAGE WOULD
ALLOW FOR INCREASED DIURNAL INSTABILITY AND THEREBY A GREATER
COVERAGE OF MIDDAY AND AFTERNOON CONVECTION. WILL FOLLOW
CONTINUITY...WHICH FAVORS CHC POPS FOR THE SECOND HALF OF THE DAY.
A SLOWER PASSAGE OF THE MID LEVEL FEATURE WOULD ALSO INCREASE THE
RISK FOR STRONG TO SEVERE CONVECTION. WHILE SBCAPES OF 1000-1500
J/KG STILL APPEAR POSSIBLE...AM LESS IMPRESSED WITH THE AMOUNT OF
SHEAR (BULK <30KTS) BEING EXPRESSED BY THE NEW GUIDANCE PACKAGE.
SPC ALSO LOOKS TO BE UNIMPRESSED AS THE AREA IS ONLY IN A GENERAL
RISK FOR THUNDERSTORMS. OTHERWISE THE VAST MAJORITY OF THE DAY
THOUGH WILL BE RAIN FREE. MAX TEMPS WILL GENERALLY RANGE FROM 75
TO 80...WITH THE HIGHER END OF THE RANGE BEING FOUND IN THE
GENESEE VALLEY AND ON THE LAKE PLAINS SOUTH OF LK ONTARIO.

IN THE WAKE OF THE DEPARTING MID LEVEL SHORTWAVE SATURDAY
EVENING... ANY RESIDUAL AFTERNOON CONVECTION WILL DIE OFF FAIRLY
QUICKLY WITH THE LOSS OF DAYTIME HEATING. THIS SHOULD LEAVE A
MAINLY DRY NIGHT ACROSS OUR REGION WITH TEMPERATURES SETTLING TO
NEAR 60 ACROSS THE LAKE PLAINS AND THE MID TO UPPER 50S EAST OF LK
ONTARIO AND ACROSS THE BULK OF THE SRN TIER.

SUNDAY SHOULD FEATURE GENERALLY FAIR WEATHER AND SLIGHTLY HIGHER
TEMPERATURES AS LOW LEVEL RIDGING WILL EXTEND ACROSS OUR REGION
FROM THE UPPER OHIO VALLEY. IT IS WORTH NOTING THOUGH THAT THE GFS
IS PAINTING A MUCH MORE UNSETTLED DAY. THE PROBLEM WITH THIS
SOLUTION THOUGH IS THAT IT STEMS FROM A SPURIOUS LOOKING AREA OF
CONVECTION THAT THE 00Z GFS GENERATES OVER THE CENTRAL PLAINS
SATURDAY EVENING...THEN TRACKS THE REMNANTS EAST ACROSS OUR REGION
FOR SUNDAY. WILL CONTINUE WITH OUR LOW CHC AFTERNOON POPS FROM
CONTINUITY...WHICH IS SUPPORTED BY THE ECMWF.

WHILE THERE WILL BE SEVERAL SHORTWAVES PASSING ACROSS OR JUST
NORTH OF OUR REGION DURING THIS PARTICULAR PERIOD...THE STRONGEST
IMPULSE IS FORECAST TO MOVE THROUGH OUR REGION MONDAY AFTERNOON OR
EVENING. THIS FEATURE WILL PUSH A FAIRLY STRONG COLD FRONT ACROSS
OUR REGION...BUT AS HIGHLIGHTED IN PREVIOUS DISCUSSIONS...THE MAIN
FORCING FOR CONVECTION MAY COME FROM A PRE-FRONTAL TROUGH. IN
EITHER CASE...HAVE BUMPED POPS TO HIGH CHC FOR THE SECOND HALF OF
MONDAY WHEN THE DEEPEST MOISTURE FIELD...JET INDUCED LIFT AND
DIURNAL INSTABILITY IS EXPECTED TO BE THE GREATEST. THE CONVECTION
WILL THEN WEAKEN AND DISSIPATE DURING THE COURSE OF MONDAY NIGHT
WHEN THE FRONT WILL PUSH TO OUR EAST.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A GENERAL DEAMPLIFICATION OF THE LONGWAVE PATTERN IS EXPECTED
OVER NORTH AMERICA DURING THIS PERIOD...AS THE GFS AND ECMWF BASED
ENSEMBLES ARE SUGGESTING THAT THE ANOMALOUSLY DEEP CLOSED LOW
CENTERED NEAR JAMES BAY WILL OPEN UP AND PUSH OUT ACROSS FAR
EASTERN QUEBEC. MEANWHILE...EXPANSIVE SFC HIGH PRESSURE OVER THE
CANADIAN PRAIRIES WILL NOSE SOUTHEAST ACROSS THE UPPER GREAT LAKES
TO THE OHIO VALLEY. THIS SHOULD PROVIDE MAINLY FAIR DRY WEATHER
ACROSS OUR REGION...WITH THE CANADIAN BASED AIRMASS SUPPORTING
BELOW NORMAL TEMPERATURES. MAX TEMPS WILL BE IN THE 70S WHILE
OVERNIGHT LOWS WILL BE IN THE 50S.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
OUTSIDE OF SOME LIMITED SOUTHERN TIER VALLEY FOG THAT SHOULD
QUICKLY MIX OUT BY MID MORNING...UNLIMITED VFR CONDITIONS WILL
CONTINUE TO PREVAIL FOR MUCH OF TODAY.

LATE THIS AFTERNOON...THE NEXT IN A SERIES OF SHORTWAVE IMPULSES
WILL BEGIN TO IMPINGE UPON THE REGION. COUPLED WITH LIFT FROM A
LAKE BREEZE CONVERGENCE ZONE...THIS COULD TOUCH OF A SHOWER OR
THUNDERSTORM NEAR KIAG. THE SHORTWAVE WILL THEN PUSH DEEPER INTO
OUR REGION TONIGHT...BRINGING MORE GENERAL CHANCES FOR SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS. ANY OF THESE WILL HAVE THE
POTENTIAL TO PRODUCE BRIEF/LOCALIZED REDUCTIONS IN CIG/VSBY...WITH
VFR CONDITIONS OTHERWISE PREVAILING.

OUTLOOK...
SATURDAY THROUGH MONDAY...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS.
TUESDAY...MAINLY VFR.

&&

.MARINE...
IN ADVANCE OF AN APPROACHING SURFACE TROUGH...A BRISK WEST-
SOUTHWESTERLY FLOW WILL REDEVELOP ON LAKE ERIE THIS AFTERNOON...
THEN WILL LINGER INTO THE EARLY EVENING HOURS. FOR THIS REASON...
A FRESH BATCH OF SMALL CRAFT ADVISORIES HAVE BEEN HOISTED FOR THE
NEARSHORE WATERS OF LAKE ERIE AND THE UPPER NIAGARA RIVER AND
BUFFALO HARBOR...WITH THE START AND END TIMES OF THESE AS OUTLINED
BELOW.

OTHERWISE...WINDS AND WAVES ARE MOSTLY EXPECTED TO REMAIN BELOW
ADVISORY LEVELS THROUGH THE FIRST HALF OF THE WEEKEND...THOUGH
LOCALLY STRONGER WINDS/HIGHER WAVES WILL BE POSSIBLE IN AND NEAR
ANY SHOWERS AND THUNDERSTORMS TONIGHT AND SATURDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
         SATURDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
         THIS EVENING FOR LEZ020.

&&

$$

SYNOPSIS...JJR
NEAR TERM...JJR
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...JJR
MARINE...JJR





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