000
FXUS63 KAPX 211048
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
648 AM EDT TUE MAY 21 2013
.SYNOPSIS...
ISSUED AT 346 AM EDT TUE MAY 21 2013
A STORM SYSTEM IN THE PLAINS WILL TAKE ITS TIME MOVING INTO THE
GREAT LAKES THIS WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF
THE REGION THURSDAY. THIS PATTERN WILL SET THE STAGE FOR CONTINUED
MILD TEMPERATURES...ALONG WITH SEVERAL CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.UPDATE...
ISSUED AT 634 AM EDT TUE MAY 21 2013
FIRST SWATH OF SHOWERS AND STORMS LIFTING UP TOWARD EASTERN
UPPER...WITH THE STORMS MORE SO LOCKED IN OVER NE LOWER...TRACKING
TOWARD DRUMMOND ISLAND. NEXT BATCH OF RAIN...WITH LESSER CHANCES
FOR EMBEDDED THUNDER...LIFTING INTO THE GTV BAY AND SAGINAW BAY
REGIONS. THERE IS NO LOW CLOUD SEEN...AND ALTHOUGH A BRIEF LOW
CLOUD DECK IS POSSIBLE FOR A BRIEF TIME THIS MORNING...DO BELIEVE
THAT REAL GOOD WARMING WILL OCCUR THROUGH THE DAY ACROSS M-68
SOUTH. THIS WILL ALLOW US TO REVEAL 1500 OR SO J/KG FOR ADDITIONAL
STORM DEVELOPMENT. NOT SEEING A REAL GOOD TRIGGER STILL...WITH THE
EXCEPTION FOR WEAK CONVERGENCE AROUND THE FRONT WHICH WILL TRY AND
EASE ITS WAY NORTH OF M-68. ALSO...MAYBE OROGRAPHIC LIFT CAN BE A
CATALYST FOR ADDITIONAL STORMS. WILL KEEP THE AFTERNOON AND EVENING
FORECAST THE SAME FOR NOW...AS THERE IS NO INDICATION STILL FOR A
CAP...DESPITE THE RISING HEIGHTS LATER TODAY AND THE EXPECTATION
FOR SUBSIDENCE BEHIND DEPARTING MID LEVEL TROUGH/PRECIPITATION.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 346 AM EDT TUE MAY 21 2013
SOMEWHAT OF A MESSY PATTERN OUT THERE RIGHT NOW...WITH CLOSED
UPPER LEVEL LOW PRESSURE ACROSS SOUTH DAKOTA WITH A SHORTWAVE
TROUGH LIFTING NE THROUGH THE MID MISSISSIPPI VALLEY. A
RE-ENERGIZED H8 LLJ OF 35-45KT WAS USHERING IN THE NEXT BATCH OF
DEEPER MOISTURE (PWATS APPROACHING 1.65") UP OUR WAY...AND
PROVIDING THE LOW LEVEL FORCING WHILE THE UPPER LEVELS WERE BEING
AIDED BY UPPER DIVERGENCE ASSOCIATED WITH RIGHT ENTRANCE REGION OF
MID/UPPER LEVEL JET. SOME ISOLATED ACTIVITY WAS DEVELOPING ALONG
M-55...BUT THE MAIN BATCH OF SHOWERS WAS STILL WORKING UP THROUGH
SRN LAKE MICHIGAN. STRONGEST OF STORMS WERE WELL SOUTH OF US
ACROSS NW INDIANA/SW LOWER...WHERE LATEST DATA SUGGESTS THAT THE
LLJ WAS BEING DIRECTED MORE WEST-EAST. WHILE MUCH OF THE MOISTURE
ADVECTION MAY PUSH THE BETTER RAINFALL OFF TO OUR SOUTH...LATEST
VAD WIND PROFILES ARE STILL SHOWING A STRENGTHENING SOUTH WINDS
ACROSS WISCONSIN.
THROUGH THE MORNING...THE UPPER LEVEL JET/DIVERGENCE WILL LIFT
ACROSS THE WESTERN GREAT LAKES ALONG WITH THE AFOREMENTIONED MID
LEVEL TROUGH. DEEP LAYER LIFT AND MOISTURE ADVECTION WILL RESULT
IN A PERIOD OF SHOWERS AND EMBEDDED THUNDERSTORMS. MUCAPE OF
SEVERAL HUNDRED J/KG IS STILL LOOKING TO NOT BE ENOUGH FOR 35-45KT
OF EFFECTIVE BULK SHEAR TO PRODUCE ANY WIDESPREAD SEVERE
WEATHER...BUT ISOLATED SEVERE STORMS WITH HAIL ARE NOT OUT OF THE
QUESTION. WILL SWING THIS INITIAL ROUND OF PRECIPITATION NORTHWARD
THROUGH THE MORNING. AREAS OF FOG...LOCALLY DENSE OFF LAKE
HURON...WILL CONTINUE TO PLAGUE MUCH OF NE LOWER AND THE STRAITS
REGION. THIS IS ALONG AND NORTH OF A NEAR STATIONARY FRONTAL
BOUNDARY WHERE EASTERLY FLOW IS COMING OFF LAKE HURON. I DO
BELIEVE THIS WILL BE A PROBLEM THROUGH A GOOD CHUNK OF THE
DAY...WITH LOW CLOUDS AND SOME FOG TO GRADUALLY DEVELOP INTO
MORE OF EASTERN UPPER. THIS TO OCCUR AS THE LOW LEVEL FLOW TRIES
TO TURN MORE SOUTHERLY BEHIND DEPARTING TROUGH AND ARRIVING WEAK
SFC LOW TRACKING TOWARD THE STRAITS.
THIS AFTERNOON...OF COURSE...THE BIG QUESTION WILL BE HOW MUCH
CLEARING OUT WILL WE GET THIS AFTERNOON?..AND WHAT WILL THE
IMPLICATIONS BE ON TEMPERATURES AND DEVELOPING DIURNAL
INSTABILITY?...ESPECIALLY OF INTEREST CONSIDERING THE DATA SHOWING
AN UNCAPPED ATMOSPHERE WITH WET BULBS DROPPING TO ROUGHLY 9KFT.
CLOUDS ARE LIKELY TO LINGER INTO THE AFTERNOON BEHIND DEPARTING
PRECIPITATION...AIDED BY OVERALL SUBSIDENCE AND HEIGHT RISES
EXPECTED IN THE MID LEVELS. A DEEPER SSW FLOW IS EXPECTED TO
DEVELOP ACROSS NRN LOWER...BUT THE WARM FRONT IS LIKELY TO NOT GET
THROUGH THE STRAITS/LAKE HURON COAST. THIS DEEPER SOUTHERLY
FLOW...IN THEORY...OUGHT TO EAT AWAY AT ANY LINGERING LOW CLOUDS
WITH LATER DAY SUNSHINE RESULTING IN UP TO 1500J/KG. NOT EXACTLY
SURE ON THE CONVECTIVE EVOLUTION...BUT ISOLATED TO SCATTERED
STORMS COULD GET FIRED OFF IN UPSLOPE FLOW WITHIN INTERIOR NRN
LOWER WITH THESE STORMS GETTING SHOVED EASTWARD. THIS IS THE ONLY
FORESEEABLE LIFTING MECHANISM (AS WELL AS THE WARM FRONT). THESE
STORMS...WORKING OFF BETTER/DEEPER INSTABILITY...WOULD HAVE A
BETTER SHOT AT PRODUCING SEVERE WEATHER. LARGE HAIL AND DAMAGING
WINDS (AS WIND PROFILES BECOME MORE UNIDIRECTIONAL) WILL BE THE
MAIN THREATS...BUT ANY TIME THERE IS A LINGERING WARM
FRONT/ENHANCED HELICITIES...A TORNADO CANNOT BE RULED OUT.
TONIGHT...CANNOT SEE A TIME TO ELIMINATE CHANCES FOR SHOWERS AND
STORMS. STRONG SHORTWAVE ENERGY DROPS IN OUT OF NE CANADA AND WILL
GRADUALLY ALLOWS THE FRONTAL SYSTEM TO SINK SOUTHWARD. WHILE THE
H8 LLJ IS NOT EXPECTED TO RAMP UP VERY STRONGLY TONIGHT...THE
SOUTH DAKOTA UPPER LOW PIVOTS INTO IOWA AND WILL LIKELY INDUCE SFC
LOW PRESSURE THAT WILL LIFT INTO LOWER MICHIGAN. ENOUGH CONFIDENCE
IN MY UNCERTAINTY ON WHERE EXACTLY THE EXACT FRONTAL/SFC LOW
POSITIONS WILL BE...BUT CAN FORESEE EITHER ANY DIURNAL CONVECTION
BEING HELD TOGETHER INTO THE EVENING...OR THE POSSIBILITY OF IT
FADING AWAY. THERE IS ALSO THE POSSIBILITY FOR LATE NIGHT
NOCTURNAL SHOWERS AND STORMS LIFTING INTO THE M-55 CORRIDOR AHEAD
OF ENERGY EJECTED FROM THE DAKOTA UPPER LOW. LOTS OF
UNCERTAINTY...BUT THEN AGAIN...THERE ALWAYS IS WITH CONVECTION.
INSTABILITY DOESN`T LOOK ALL THAT IMPRESSIVE OVERNIGHT...SO GOTTA
BELIEVE THAT THE BEST SHOT AT SEVERE WEATHER WILL BE TIED TO LATER
THIS AFTERNOON AND INTO THE EVENING.
HIGH TEMPERATURES WILL RANGE FROM THE LOWER 60S IN EASTERN UPPER
(COOLER IF STRATUS/FOG BECOME WIDESPREAD)...TO WELL INTO THE 70S
AND THE LOWER HALF OF THE 80S IN THE MIXED OUT BL ACROSS NRN
LOWER. OF COURSE...COOLER IN EASTERLY FLOW OFF OF LAKE HURON FROM
ROUGHLY M-68 NORTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EDT TUE MAY 21 2013
WEDNESDAY...BOTH THE GFS AND ECMWF HAVE THE SFC LOW OVER S LOWER,
WITH THE 500 MB LOW TO THE WEST, WITH THE 500 MB JET OVER NE LOWER.
SO THE EXPECTATION IS THAT THE LIKELY AREA OF THUNDERSTORMS WOULD BE
SOUTH AND EAST OF A LINE FROM ALPENA TO MANISTEE. WITH LESS FORCING
IN E UPPER, WOULD EXPECT THAT THE CHANCES ARE MUCH LESS.
WEDNESDAY NIGHT...THE 500 MB TROUGH BEGINS TO MOVE THROUGH THE
FORECAST AREA WITH THE SFC LOW MOVING EAST OF THE REGION. THIS
BRINGS IN LOTS OF COOL DRY AIR WITH THE 70--500 MB LAYER RH FALLING
TO THE SINGLE DIGITS AND THE 850 MB MOISTURE TO AROUND 15%. 850 MB
TEMPERATURES ARE ALSO GOING TO FALL INTO THE SINGLE DIGITS, THAT THE
SET UP FOR THE FOLLOWING DAY, WILL NOW BE CHILLY. ESPECIALLY, SINCE
MOST PEOPLE HAVE GOTTEN USED TO THE 70S AND 80S.
THURSDAY...AS WAS SAID IN THE PREVIOUS PARAGRAPH, THE TEMPERATURES
WILL END UP BEING CHILLY AS THE 850 MB TEMPERATURES APPROACH 0C BY
00Z. THE ONLY THING THAT WE HAVE GOING FOR US WILL BE THE MOSTLY
SUNNY SKY AS THE RH IN THE LOWER AND MID LEVELS OF THE ATMOSPHERE
DRY OUT TO AROUND 10%. THIS WILL ALLOW US TO WARM UNDER FULL SUN.
WITH THE SFC HIGH BUILDING IN THE REGION, WINDS SHOULD BEGIN TO
SETTLE DOWN A BIT AS THE GRADIENT BEGINS TO SLACKEN. OVERNIGHT, AS
THE TEMPERATURES DIP TOWARD FREEZING AND THE WINDS DIMINISH, WILL
EXPECT THAT THE FROST WILL BE AN ISSUE. AT THIS POINT, HAVE PATCHY
AND AREAS OF FROST, BUT IT MAY HAVE TO BE WIDENED AS THE
TEMPERATURES HAVE A CHANCE TO FALL BELOW FREEZING IF CORE OF THE
HIGH SETS UP OVER LIKE THE ECMWF SHOWS.
EXTENDED (FRIDAY THROUGH MONDAY)...FRIDAY, HIGH PRESSURE BUILDS INTO
THE REGION AND KEEPS THE FORECAST AREA DRY. SATURDAY, THE HIGH
PRESSURE REMAINS IN PLACE AND CONTINUES TO KEEP THE PLACE DRY.
SUNDAY, HIGH PRESSURE CONTINUES, SO THE WEEKEND ITSELF LOOKS GOOD
FOR GETTING OUTSIDE. MONDAY, OVER N MICHIGAN LOOKS DRY. IF THE ECMWF
IS RIGHT THEN THE DAY SHOULD TURN OUT MOSTLY SUNNY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 634 AM EDT TUE MAY 21 2013
MOIST FLOW OVER COLD LAKE HURON AND EASTERLY FLOW RESULTING IN
IFR/LIFR STRATUS AND FOG FOR APN AND TO SOME DEGREE PLN...ALTHOUGH
THE ARRIVAL OF SHOWERS AND STORMS HAVE HELPED THE VSBYS. STILL
EXPECTING SOME DETERIORATION OF VSBYS AND LOW CIGS FOR A GOOD
CHUNK OF THE DAY AT APN. THE FLOW DOES TRY AND GO MORE SOUTHERLY
BY LATER TODAY WHICH COULD HELP LIFT THINGS INTO VFR. LESS
CONFIDENCE IN THAT. ELSEWHERE...SOME LIGHT RAIN AND MAYBE SOME
EMBEDDED THUNDER ARRIVES THROUGH THE MORNING...BEFORE A QUIET
PERIOD OF OF WEATHER. HEATING THIS AFTERNOON WILL REVEAL MORE
INSTABILITY...BUT SEEMING LIKE A LACK OF A LIFTING MECHANISM FOR
ANYTHING WIDESPREAD IN ADDITIONAL STORM DEVELOPMENT. THE THUNDER
IS ALREADY IN THE FORECAST FOR THIS AFTERNOON...AND WILL NOT
CHANGE THAT ATTM. STORMS WOULD LIKELY CONTINUE INTO THE
EVENING...WHILE THE FRONT WILL ONLY SLOWLY EASE SOUTHWARD THROUGH
THE NIGHT...WITH ADDITIONAL UPPER LEVEL DISTURBANCES TO POSSIBLY
INITIATE NOCTURNAL SHOWER/STORM DEVELOPMENT LATE IN THE TAF
PERIOD.
WINDS WILL HAVE AN EASTERLY KICK ACROSS APN MUCH OF THE DAY...WITH
THE BL MIXING OUT ELSEWHERE...WITH SSW WINDS GUSTING UP TO 20KTS.
&&
.MARINE...
ISSUED AT 346 AM EDT TUE MAY 21 2013
WARM AIR/MOIST OVER COLD LAKE WATERS WILL KEEP WINDS AT BAY...BUT
AREAS OF FOG AND LOW CLOUDS WILL BE SEEN ACROSS MUCH OF NRN LAKE
HURON AND THE STRAITS/LAKE SUPERIOR INTO TODAY. PERIODS OF SHOWERS
AND STORMS WILL BE COMMON AS WELL...DUE TO A NEAR STATIONARY
FRONTAL ZONE STRETCHED OVER NRN LOWER. THIS FRONT WILL DIVE SOUTH
OF US WEDNESDAY...ALLOWING A TIGHTER PRESSURE GRADIENT TO DEVELOP
WEDNESDAY NIGHT THROUGH THURSDAY. AS COLDER AIR POURS IN...THE
STABILITY WEAKENS AND SMALL CRAFT ADVISORY GUSTS LOOK LIKE A GOOD
BET. HIGHER PRESSURE SETTLES IN FRIDAY AND INTO THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SD
SYNOPSIS...JL
SHORT TERM...SD
LONG TERM...JL
AVIATION...SD
MARINE...SD
000
FXUS63 KAPX 210746
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
346 AM EDT TUE MAY 21 2013
.SYNOPSIS...
ISSUED AT 346 AM EDT TUE MAY 21 2013
A STORM SYSTEM IN THE PLAINS WILL TAKE ITS TIME MOVING INTO THE
GREAT LAKES THIS WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF
THE REGION THURSDAY. THIS PATTERN WILL SET THE STAGE FOR CONTINUED
MILD TEMPERATURES...ALONG WITH SEVERAL CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 346 AM EDT TUE MAY 21 2013
SOMEWHAT OF A MESSY PATTERN OUT THERE RIGHT NOW...WITH CLOSED
UPPER LEVEL LOW PRESSURE ACROSS SOUTH DAKOTA WITH A SHORTWAVE
TROUGH LIFTING NE THROUGH THE MID MISSISSIPPI VALLEY. A
RE-ENERGIZED H8 LLJ OF 35-45KT WAS USHERING IN THE NEXT BATCH OF
DEEPER MOISTURE (PWATS APPROACHING 1.65") UP OUR WAY...AND
PROVIDING THE LOW LEVEL FORCING WHILE THE UPPER LEVELS WERE BEING
AIDED BY UPPER DIVERGENCE ASSOCIATED WITH RIGHT ENTRANCE REGION OF
MID/UPPER LEVEL JET. SOME ISOLATED ACTIVITY WAS DEVELOPING ALONG
M-55...BUT THE MAIN BATCH OF SHOWERS WAS STILL WORKING UP THROUGH
SRN LAKE MICHIGAN. STRONGEST OF STORMS WERE WELL SOUTH OF US
ACROSS NW INDIANA/SW LOWER...WHERE LATEST DATA SUGGESTS THAT THE
LLJ WAS BEING DIRECTED MORE WEST-EAST. WHILE MUCH OF THE MOISTURE
ADVECTION MAY PUSH THE BETTER RAINFALL OFF TO OUR SOUTH...LATEST
VAD WIND PROFILES ARE STILL SHOWING A STRENGTHENING SOUTH WINDS
ACROSS WISCONSIN.
THROUGH THE MORNING...THE UPPER LEVEL JET/DIVERGENCE WILL LIFT
ACROSS THE WESTERN GREAT LAKES ALONG WITH THE AFOREMENTIONED MID
LEVEL TROUGH. DEEP LAYER LIFT AND MOISTURE ADVECTION WILL RESULT
IN A PERIOD OF SHOWERS AND EMBEDDED THUNDERSTORMS. MUCAPE OF
SEVERAL HUNDRED J/KG IS STILL LOOKING TO NOT BE ENOUGH FOR 35-45KT
OF EFFECTIVE BULK SHEAR TO PRODUCE ANY WIDESPREAD SEVERE
WEATHER...BUT ISOLATED SEVERE STORMS WITH HAIL ARE NOT OUT OF THE
QUESTION. WILL SWING THIS INITIAL ROUND OF PRECIPITATION NORTHWARD
THROUGH THE MORNING. AREAS OF FOG...LOCALLY DENSE OFF LAKE
HURON...WILL CONTINUE TO PLAGUE MUCH OF NE LOWER AND THE STRAITS
REGION. THIS IS ALONG AND NORTH OF A NEAR STATIONARY FRONTAL
BOUNDARY WHERE EASTERLY FLOW IS COMING OFF LAKE HURON. I DO
BELIEVE THIS WILL BE A PROBLEM THROUGH A GOOD CHUNK OF THE
DAY...WITH LOW CLOUDS AND SOME FOG TO GRADUALLY DEVELOP INTO
MORE OF EASTERN UPPER. THIS TO OCCUR AS THE LOW LEVEL FLOW TRIES
TO TURN MORE SOUTHERLY BEHIND DEPARTING TROUGH AND ARRIVING WEAK
SFC LOW TRACKING TOWARD THE STRAITS.
THIS AFTERNOON...OF COURSE...THE BIG QUESTION WILL BE HOW MUCH
CLEARING OUT WILL WE GET THIS AFTERNOON?..AND WHAT WILL THE
IMPLICATIONS BE ON TEMPERATURES AND DEVELOPING DIURNAL
INSTABILITY?...ESPECIALLY OF INTEREST CONSIDERING THE DATA SHOWING
AN UNCAPPED ATMOSPHERE WITH WET BULBS DROPPING TO ROUGHLY 9KFT.
CLOUDS ARE LIKELY TO LINGER INTO THE AFTERNOON BEHIND DEPARTING
PRECIPITATION...AIDED BY OVERALL SUBSIDENCE AND HEIGHT RISES
EXPECTED IN THE MID LEVELS. A DEEPER SSW FLOW IS EXPECTED TO
DEVELOP ACROSS NRN LOWER...BUT THE WARM FRONT IS LIKELY TO NOT GET
THROUGH THE STRAITS/LAKE HURON COAST. THIS DEEPER SOUTHERLY
FLOW...IN THEORY...OUGHT TO EAT AWAY AT ANY LINGERING LOW CLOUDS
WITH LATER DAY SUNSHINE RESULTING IN UP TO 1500J/KG. NOT EXACTLY
SURE ON THE CONVECTIVE EVOLUTION...BUT ISOLATED TO SCATTERED
STORMS COULD GET FIRED OFF IN UPSLOPE FLOW WITHIN INTERIOR NRN
LOWER WITH THESE STORMS GETTING SHOVED EASTWARD. THIS IS THE ONLY
FORESEEABLE LIFTING MECHANISM (AS WELL AS THE WARM FRONT). THESE
STORMS...WORKING OFF BETTER/DEEPER INSTABILITY...WOULD HAVE A
BETTER SHOT AT PRODUCING SEVERE WEATHER. LARGE HAIL AND DAMAGING
WINDS (AS WIND PROFILES BECOME MORE UNIDIRECTIONAL) WILL BE THE
MAIN THREATS...BUT ANY TIME THERE IS A LINGERING WARM
FRONT/ENHANCED HELICITIES...A TORNADO CANNOT BE RULED OUT.
TONIGHT...CANNOT SEE A TIME TO ELIMINATE CHANCES FOR SHOWERS AND
STORMS. STRONG SHORTWAVE ENERGY DROPS IN OUT OF NE CANADA AND WILL
GRADUALLY ALLOWS THE FRONTAL SYSTEM TO SINK SOUTHWARD. WHILE THE
H8 LLJ IS NOT EXPECTED TO RAMP UP VERY STRONGLY TONIGHT...THE
SOUTH DAKOTA UPPER LOW PIVOTS INTO IOWA AND WILL LIKELY INDUCE SFC
LOW PRESSURE THAT WILL LIFT INTO LOWER MICHIGAN. ENOUGH CONFIDENCE
IN MY UNCERTAINTY ON WHERE EXACTLY THE EXACT FRONTAL/SFC LOW
POSITIONS WILL BE...BUT CAN FORESEE EITHER ANY DIURNAL CONVECTION
BEING HELD TOGETHER INTO THE EVENING...OR THE POSSIBILITY OF IT
FADING AWAY. THERE IS ALSO THE POSSIBILITY FOR LATE NIGHT
NOCTURNAL SHOWERS AND STORMS LIFTING INTO THE M-55 CORRIDOR AHEAD
OF ENERGY EJECTED FROM THE DAKOTA UPPER LOW. LOTS OF
UNCERTAINTY...BUT THEN AGAIN...THERE ALWAYS IS WITH CONVECTION.
INSTABILITY DOESN`T LOOK ALL THAT IMPRESSIVE OVERNIGHT...SO GOTTA
BELIEVE THAT THE BEST SHOT AT SEVERE WEATHER WILL BE TIED TO LATER
THIS AFTERNOON AND INTO THE EVENING.
HIGH TEMPERATURES WILL RANGE FROM THE LOWER 60S IN EASTERN UPPER
(COOLER IF STRATUS/FOG BECOME WIDESPREAD)...TO WELL INTO THE 70S
AND THE LOWER HALF OF THE 80S IN THE MIXED OUT BL ACROSS NRN
LOWER. OF COURSE...COOLER IN EASTERLY FLOW OFF OF LAKE HURON FROM
ROUGHLY M-68 NORTH.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EDT TUE MAY 21 2013
WEDNESDAY...BOTH THE GFS AND ECMWF HAVE THE SFC LOW OVER S LOWER,
WITH THE 500 MB LOW TO THE WEST, WITH THE 500 MB JET OVER NE LOWER.
SO THE EXPECTATION IS THAT THE LIKELY AREA OF THUNDERSTORMS WOULD BE
SOUTH AND EAST OF A LINE FROM ALPENA TO MANISTEE. WITH LESS FORCING
IN E UPPER, WOULD EXPECT THAT THE CHANCES ARE MUCH LESS.
WEDNESDAY NIGHT...THE 500 MB TROUGH BEGINS TO MOVE THROUGH THE
FORECAST AREA WITH THE SFC LOW MOVING EAST OF THE REGION. THIS
BRINGS IN LOTS OF COOL DRY AIR WITH THE 70--500 MB LAYER RH FALLING
TO THE SINGLE DIGITS AND THE 850 MB MOISTURE TO AROUND 15%. 850 MB
TEMPERATURES ARE ALSO GOING TO FALL INTO THE SINGLE DIGITS, THAT THE
SET UP FOR THE FOLLOWING DAY, WILL NOW BE CHILLY. ESPECIALLY, SINCE
MOST PEOPLE HAVE GOTTEN USED TO THE 70S AND 80S.
THURSDAY...AS WAS SAID IN THE PREVIOUS PARAGRAPH, THE TEMPERATURES
WILL END UP BEING CHILLY AS THE 850 MB TEMPERATURES APPROACH 0C BY
00Z. THE ONLY THING THAT WE HAVE GOING FOR US WILL BE THE MOSTLY
SUNNY SKY AS THE RH IN THE LOWER AND MID LEVELS OF THE ATMOSPHERE
DRY OUT TO AROUND 10%. THIS WILL ALLOW US TO WARM UNDER FULL SUN.
WITH THE SFC HIGH BUILDING IN THE REGION, WINDS SHOULD BEGIN TO
SETTLE DOWN A BIT AS THE GRADIENT BEGINS TO SLACKEN. OVERNIGHT, AS
THE TEMPERATURES DIP TOWARD FREEZING AND THE WINDS DIMINISH, WILL
EXPECT THAT THE FROST WILL BE AN ISSUE. AT THIS POINT, HAVE PATCHY
AND AREAS OF FROST, BUT IT MAY HAVE TO BE WIDENED AS THE
TEMPERATURES HAVE A CHANCE TO FALL BELOW FREEZING IF CORE OF THE
HIGH SETS UP OVER LIKE THE ECMWF SHOWS.
EXTENDED (FRIDAY THROUGH MONDAY)...FRIDAY, HIGH PRESSURE BUILDS INTO
THE REGION AND KEEPS THE FORECAST AREA DRY. SATURDAY, THE HIGH
PRESSURE REMAINS IN PLACE AND CONTINUES TO KEEP THE PLACE DRY.
SUNDAY, HIGH PRESSURE CONTINUES, SO THE WEEKEND ITSELF LOOKS GOOD
FOR GETTING OUTSIDE. MONDAY, OVER N MICHIGAN LOOKS DRY. IF THE ECMWF
IS RIGHT THEN THE DAY SHOULD TURN OUT MOSTLY SUNNY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1201 AM EDT TUE MAY 21 2013
NEARLY STATIONARY BOUNDARY CONTINUES TO DISSECT THE TAF SITES
FROM NORTHWEST TO SOUTHEAST. THIS IS EXPECTED TO KEEP PLN AND APN
IN THE LOW CLOUDS AND FOG...DENSE AT APN OVERNIGHT WITH PATCHY FOG
AT TVC AND MBL. ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO MOVE INTO MBL AND TVC EARLY THIS MORNING AND SPREAD INTO PLN
AND APN LATE. MORE SHOWERS AND THUNDERSTORMS ARE LIKELY DURING THE
DAY AS WELL.
&&
.MARINE...
ISSUED AT 346 AM EDT TUE MAY 21 2013
WARM AIR/MOIST OVER COLD LAKE WATERS WILL KEEP WINDS AT BAY...BUT
AREAS OF FOG AND LOW CLOUDS WILL BE SEEN ACROSS MUCH OF NRN LAKE
HURON AND THE STRAITS/LAKE SUPERIOR INTO TODAY. PERIODS OF SHOWERS
AND STORMS WILL BE COMMON AS WELL...DUE TO A NEAR STATIONARY
FRONTAL ZONE STRETCHED OVER NRN LOWER. THIS FRONT WILL DIVE SOUTH
OF US WEDNESDAY...ALLOWING A TIGHTER PRESSURE GRADIENT TO DEVELOP
WEDNESDAY NIGHT THROUGH THURSDAY. AS COLDER AIR POURS IN...THE
STABILITY WEAKENS AND SMALL CRAFT ADVISORY GUSTS LOOK LIKE A GOOD
BET. HIGHER PRESSURE SETTLES IN FRIDAY AND INTO THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...JL
SHORT TERM...SD
LONG TERM...JL
AVIATION...AS
MARINE...SD
000
FXUS63 KAPX 210551
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
151 AM EDT TUE MAY 21 2013
.SYNOPSIS...
ISSUED AT 402 PM EDT MON MAY 20 2013
A STORM SYSTEM IN THE PLAINS WILL MOVE INTO THE GREAT LAKES THIS
WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF THE REGION THURSDAY.
THIS PATTERN WILL SET THE STAGE FOR CONTINUED MILD TEMPERATURES...
ALONG WITH SEVERAL CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.UPDATE...
ISSUED AT 144 AM EDT TUE MAY 21 2013
STATIONARY FRONT REMAINS DRAPED ACROSS FAR NRN LOWER MICHIGAN WITH
AN EASTERLY FLOW BRINGING LOW CLOUDS AND FOG TO AREAS ALONG AND
NORTH OF IT THROUGH THE STRAITS. A DOWNSLOPING FLOW FROM ONTARIO
HAS KEPT FOG FREE FROM MOST OF EASTERN UPPER. MEANWHILE...SHOWERS
AND STORMS WERE DEVELOPING/MOVING UP THROUGH SRN LAKE MICHIGAN AND
WERE SET TO MOVE INTO THE SRN/SW CWA OVER THE NEXT FEW HOURS. THIS
WAS THE GENERAL IDEA OF THE FORECAST AND HAVE JUST DETAILED OUT
TIMING THE PRECIPITATION. LATEST HI RES DATA SUGGESTING THAT
SHOWERS AND STORMS WILL EXPAND ACROSS ALL OF NRN MICHIGAN THROUGH
DAYBREAK. WITH A MID/UPPER JET EJECTING NORTHEAST ASSOCIATED WITH
A MID LEVEL TROUGH AND RAMPED UP H8 LLJ...THIS IDEA SEEMS MORE
THAN APPROPRIATE. SEVERAL HUNDRED J/KG OF MUCAPE IS LIKELY NOT
ENOUGH TO LEAD TO ANY SEVERE WEATHER DESPITE 35-40KT OF EFFECTIVE
BULK SHEAR.
UPDATE ISSUED AT 949 PM EDT MON MAY 20 2013
THE WARM AND HUMID AIRMASS IN COMBINATION WITH LIGHT WINDS AND LOW
LEVEL MOISTURE FROM THE RAIN THAT FELL EARLIER TODAY HAS LED TO
FOG FORMATION ACROSS PORTIONS OF THE FORECAST AREA. THE FOG IS
DENSE IN A COUPLE OF SPOTS AS WELL. WILL HAVE TO MONITOR LATEST
TRENDS ON THIS ONE TO SEE IF THE FOG BECOMES WIDESPREAD OVERNIGHT.
MEANWHILE...THE NEXT SPOKE OF ENERGY ROTATING AROUND LARGE UPPER
LOW CENTERED OVER MINNESOTA IS MOVING UP ACROSS ILLINOIS. IN
ADDITION...SURFACE WARM FRONT CONTINUES TO BE DRAPED FROM NEAR
CHARLEVOIX TO JUST NORTH OF OSCODA. THEREFORE...SHOWER AND
THUNDERSTORM ACTIVITY ASSOCIATED WITH THE UPPER LEVEL FEATURE IS
EXPECTED TO ARRIVE ACROSS SOUTHWESTERN PORTIONS OF THE FORECAST
AREA LATE OVERNIGHT. ACTIVITY SHOULD THEN SPREAD NORTHEAST AS
ANOTHER THETA-E RIDGE BUILDS IN AND COMBINES WITH A STRENGTHENING
LOW LEVEL JET. AT THIS POINT AM NOT EXPECTED SEVERE STORMS AS
OVERALL INSTABILITY IS MINIMAL...THOUGH IT CAN NOT BE TOTALLY
RULED OUT WITH EFFECTIVE BULK SHEAR OF 35 TO 40 KNOTS AND MOST
UNSTABLE CAPE NEAR 1000 J/KG.
UPDATE ISSUED AT 741 PM EDT MON MAY 20 2013
FIRST ROUND OF CONVECTION NOW TO THE EAST OF THE FORECAST AREA
WITH SATELLITE/RADAR/SURFACE DATA SUGGESTING A BREAK IN THE ACTION OVER
THE NEXT FEW HOURS AT A MINIMUM. MODELS ARE BRINGING ANOTHER ROUND
OF SHOWERS AND THUNDERSTORMS BACK INTO THE REGION OVERNIGHT...SO
THAT WILL BE THE MAIN CHALLENGE OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
OVERVIEW: SPLIT FLOW PATTERN ACROSS THE CONUS WITH A BROAD CLOSED
TROUGH IN THE PLAINS CENTERED OVER THE EASTERN DAKOTAS. STRONG
IMPULSE ROTATING AROUND THE EASTERN FLANK OF THE LOW NOW PRESSING UP
INTO THE WESTERN GREAT LAKES. ACTING ON DECENT INSTABILITY AXIS
STRETCHED UP THROUGH NRN LOWER MICHIGAN (MLCAPE VALUES RUNNING
UPWARD OF 1500 J/KG)...PRODUCING A THIN CORRIDOR OF STORMS ADVANCING
THROUGH THE REGION. A FEW SEVERE HAIL REPORTS AND GUSTS OF 40 TO 50
MPH...BUT OVERALL EVENT IS A LITTLE DISAPPOINTING...SO FAR.
TONIGHT...LINE OF STORMS LOOKING TO ADVANCE OUT OF THE CWA BY EARLY
EVENING WITH A WEDGE OF DRIER AIR/SUBSIDENCE/NO PRECIP BUILDING INTO
THE AREA FOR THE BULK OF THE EVENING. WINDS WEAKEN...AND WITH THE
AFTERNOON RAINFALL...A PRETTY GOOD SETUP FOR DEVELOPMENT OF SOME LOW
CLOUDS AND FOG AS WE GO THROUGH THE EVENING.
THEN...FORECAST A BIT MORE NEBULOUS OVERNIGHT INTO TUESDAY. LOW
PRESSURE IN THE NRN PLAINS TODAY SLOWLY DRIFTS EASTWARD INTO THE
WESTERN GREAT LAKES WITH THE SFC FRONT REMAINING STRETCHED OUT INTO
LOWER MICHIGAN. STILL A DECENT SIGNAL THAT WE SEE RENEWED CONVECTIVE
DEVELOPMENT ALONG THAT FRONT LATER TONIGHT AS THE LOW LEVEL JET
INCREASES AND SO WILL CONTINUE WITH OUR GOING FORECAST OF LIKELY
POPS ADVANCING WEST-EAST INTO THE CWA DURING THE OVERNIGHT PERIOD.
LOW SEVERE THREAT OVERNIGHT...BETTER SEVERE THREAT ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
AMPLIFIED PATTERN WILL CONTINUE TO PUMP GULF MOISTURE INTO NORTHERN
MICHIGAN THROUGH WEDNESDAY...PROVIDING CHANCES FOR RAIN AND
THUNDERSTORMS. THUNDERSTORM KINEMATICS ARE GREAT TUESDAY AFTERNOON.
ALTHOUGH IF THERE IS LINGERING CLOUDS FROM TONIGHT AND EARLY TUESDAY
MORNING/S CONVECTION...DIURNAL HEATING MAY BE VERY
MINIMAL...HINDERING ATMOSPHERIC DESTABILIZATION NEEDED FOR
THUNDERSTORM DEVELOPMENT. THERE WILL BE A COOL DOWN ONCE
THIS SLOW MOVING AMPLIFIED TROUGH MOVES THROUGH THE GREAT LAKES
REGION WITH CHILLY FRIDAY AND SATURDAY MORNINGS AND MAX TEMPERATURES
ONLY REACHING INTO THE MID 50S TO MID 60S THURSDAY AND RIGHT ON
THROUGH THE MEMORIAL DAY WEEKEND.
TUESDAY MORNING THROUGH WEDNESDAY NIGHT...ANY LINGERING PATCHY FOG
WILL DIMINISH IN THE EARLY MORNING HOURS. IN DAY 2 SLIGHT RISK FROM
SPC. SO THE BIG QUESTION IS...WILL THE SUN BREAK OUT OVER NORTHERN
MICHIGAN TUESDAY BEHIND TONIGHT/S CONVECTION? THE INGREDIENTS FOR
STRONG/SEVERE THUNDERSTORMS ARE MOST CERTAINLY THERE WITH SFC DEW
POINTS FORECAST TO BE IN THE UPPER 50S TO LOW 60S...GOOD LOW TO
MID-LEVEL DIRECTIONAL SHEAR...0-6KM BULK SHEAR 50-60 KTS...GOOD JET
DYNAMICS AND MLCAPE 1100 J/KG WITH VERY MINIMAL MLCINH. WITH THE
0-6KM BULK SHEAR VECTORS AT A 45 DEGREE ANGLE TO THE EAST-WEST
ORIENTED BOUNDARY LAYER DRAPED OVER NORTHERN LOWER MICHIGAN...ANY
STORMS THAT DO DEVELOP SHOULD BE CELLULAR AT FIRST AND CHANGE TO
LINEAR WITH TIME. WITH -10 TO -30C CAPE OF 500-600 J/KG AND LAPSE
RATES BETWEEN 6.5-7 C/KM...HAIL WILL BE A THREAT WITH ANY STORM THAT
DOES DEVELOP. OF COURSE LOCATION WILL PROBABLY CHANGE BY
TOMORROW...BUT AS OF RIGHT NOW OUR SOUTHERN CWA SEEMS TO BE THE
FAVORED AREA TOMORROW FOR THUNDERSTORM ACTIVITY.
WEDNESDAY...ALTHOUGH THUNDERSTORMS ARE ONCE AGAIN POSSIBLE WEDNESDAY
AFTERNOON THE SEVERE THREAT SHOULD BE GONE. DIURNAL HEATING WILL
PRODUCE CHANCES OF RAIN AND THUNDERSTORMS WEDNESDAY AFTERNOON. STILL
TAPPED INTO GULF MOISTURE WITH PWAT VALUES ABOVE 1.00 INCH AND
AROUND 1000 J/KG OF SKINNY CAPE...EXPECT ANY RAIN OR THUNDERSTORMS
THAT DO DEVELOP TO PRODUCE HEAVY RAIN.
THURSDAY...LOW PRESSURE CENTER MOVES DIRECTLY OVER
MICHIGAN...PRODUCING RAIN WHICH MAY BE HEAVY AT TIMES. AS THE LOW
PRESSURE CENTER FINALLY BEGINS TO MOVE OFF TO THE EAST...A LARGE
HIGH PRESSURE CENTER OVER WESTERN CANADA BUILDS INTO THE
REGION...ENDING PRECIPITATION FROM NORTHWEST TO SOUTHEAST BEGINNING
IN THE EARLY AFTERNOON HOURS AS MUCH DRIER AND COOLER AIR MOVES IN
OVER NORTHERN MICHIGAN.
MEMORIAL DAY WEEKEND (FRIDAY THROUGH MONDAY)...DRY FORECAST FOR THE
EXTENDED HOLIDAY WEEKEND WITH A LARGE AREA OF HIGH PRESSURE
CONTINUING TO BUILD OVER THE GREAT LAKES REGION. COOLER...WITH
TEMPERATURES ONLY REACHING INTO THE 60S. FROST IS POSSIBLE FRIDAY
AND SATURDAY MORNING...ALTHOUGH MODELS HAVE BEEN TRENDING SOMEWHAT
WARMER. LEFT INHERITED FROST IN THE GRIDS FOR SATURDAY MORNING UNTIL
MORE CONFIDENCE IS ACHIEVED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1201 AM EDT TUE MAY 21 2013
NEARLY STATIONARY BOUNDARY CONTINUES TO DISSECT THE TAF SITES
FROM NORTHWEST TO SOUTHEAST. THIS IS EXPECTED TO KEEP PLN AND APN
IN THE LOW CLOUDS AND FOG...DENSE AT APN OVERNIGHT WITH PATCHY FOG
AT TVC AND MBL. ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO MOVE INTO MBL AND TVC EARLY THIS MORNING AND SPREAD INTO PLN
AND APN LATE. MORE SHOWERS AND THUNDERSTORMS ARE LIKELY DURING THE
DAY AS WELL.
&&
.MARINE...
ISSUED AT 402 PM EDT MON MAY 20 2013
SOME GUSTINESS WILL BE FELT ON THE LAKES INTO THE EVENING WITH A
FEW GUSTS INTO THE 20 TO 25 KNOT RANGE. BUT WINDS DIMINISH TONIGHT
AND REMAIN ON THE LIGHTER SIDE THROUGH WEDNESDAY AS AN AREA OF
LOW PRESSURE SLOWLY WORKS THROUGH THE REGION.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SD
SYNOPSIS...SR
SHORT TERM...BA
LONG TERM...TL
AVIATION...AS
MARINE...BA
000
FXUS63 KAPX 210405
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1205 AM EDT TUE MAY 21 2013
.SYNOPSIS...
ISSUED AT 402 PM EDT MON MAY 20 2013
A STORM SYSTEM IN THE PLAINS WILL MOVE INTO THE GREAT LAKES THIS
WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF THE REGION THURSDAY.
THIS PATTERN WILL SET THE STAGE FOR CONTINUED MILD TEMPERATURES...
ALONG WITH SEVERAL CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.UPDATE...
ISSUED AT 949 PM EDT MON MAY 20 2013
THE WARM AND HUMID AIRMASS IN COMBINATION WITH LIGHT WINDS AND LOW
LEVEL MOISTURE FROM THE RAIN THAT FELL EARLIER TODAY HAS LED TO
FOG FORMATION ACROSS PORTIONS OF THE FORECAST AREA. THE FOG IS
DENSE IN A COUPLE OF SPOTS AS WELL. WILL HAVE TO MONITOR LATEST
TRENDS ON THIS ONE TO SEE IF THE FOG BECOMES WIDESPREAD OVERNIGHT.
MEANWHILE...THE NEXT SPOKE OF ENERGY ROTATING AROUND LARGE UPPER
LOW CENTERED OVER MINNESOTA IS MOVING UP ACROSS ILLINOIS. IN
ADDITION...SURFACE WARM FRONT CONTINUES TO BE DRAPED FROM NEAR
CHARLEVOIX TO JUST NORTH OF OSCODA. THEREFORE...SHOWER AND
THUNDERSTORM ACTIVITY ASSOCIATED WITH THE UPPER LEVEL FEATURE IS
EXPECTED TO ARRIVE ACROSS SOUTHWESTERN PORTIONS OF THE FORECAST
AREA LATE OVERNIGHT. ACTIVITY SHOULD THEN SPREAD NORTHEAST AS
ANOTHER THETA-E RIDGE BUILDS IN AND COMBINES WITH A STRENGTHENING
LOW LEVEL JET. AT THIS POINT AM NOT EXPECTED SEVERE STORMS AS
OVERALL INSTABILITY IS MINIMAL...THOUGH IT CAN NOT BE TOTALLY
RULED OUT WITH EFFECTIVE BULK SHEAR OF 35 TO 40 KNOTS AND MOST
UNSTABLE CAPE NEAR 1000 J/KG.
UPDATE ISSUED AT 741 PM EDT MON MAY 20 2013
FIRST ROUND OF CONVECTION NOW TO THE EAST OF THE FORECAST AREA
WITH SATELLITE/RADAR/SURFACE DATA SUGGESTING A BREAK IN THE ACTION OVER
THE NEXT FEW HOURS AT A MINIMUM. MODELS ARE BRINGING ANOTHER ROUND
OF SHOWERS AND THUNDERSTORMS BACK INTO THE REGION OVERNIGHT...SO
THAT WILL BE THE MAIN CHALLENGE OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
OVERVIEW: SPLIT FLOW PATTERN ACROSS THE CONUS WITH A BROAD CLOSED
TROUGH IN THE PLAINS CENTERED OVER THE EASTERN DAKOTAS. STRONG
IMPULSE ROTATING AROUND THE EASTERN FLANK OF THE LOW NOW PRESSING UP
INTO THE WESTERN GREAT LAKES. ACTING ON DECENT INSTABILITY AXIS
STRETCHED UP THROUGH NRN LOWER MICHIGAN (MLCAPE VALUES RUNNING
UPWARD OF 1500 J/KG)...PRODUCING A THIN CORRIDOR OF STORMS ADVANCING
THROUGH THE REGION. A FEW SEVERE HAIL REPORTS AND GUSTS OF 40 TO 50
MPH...BUT OVERALL EVENT IS A LITTLE DISAPPOINTING...SO FAR.
TONIGHT...LINE OF STORMS LOOKING TO ADVANCE OUT OF THE CWA BY EARLY
EVENING WITH A WEDGE OF DRIER AIR/SUBSIDENCE/NO PRECIP BUILDING INTO
THE AREA FOR THE BULK OF THE EVENING. WINDS WEAKEN...AND WITH THE
AFTERNOON RAINFALL...A PRETTY GOOD SETUP FOR DEVELOPMENT OF SOME LOW
CLOUDS AND FOG AS WE GO THROUGH THE EVENING.
THEN...FORECAST A BIT MORE NEBULOUS OVERNIGHT INTO TUESDAY. LOW
PRESSURE IN THE NRN PLAINS TODAY SLOWLY DRIFTS EASTWARD INTO THE
WESTERN GREAT LAKES WITH THE SFC FRONT REMAINING STRETCHED OUT INTO
LOWER MICHIGAN. STILL A DECENT SIGNAL THAT WE SEE RENEWED CONVECTIVE
DEVELOPMENT ALONG THAT FRONT LATER TONIGHT AS THE LOW LEVEL JET
INCREASES AND SO WILL CONTINUE WITH OUR GOING FORECAST OF LIKELY
POPS ADVANCING WEST-EAST INTO THE CWA DURING THE OVERNIGHT PERIOD.
LOW SEVERE THREAT OVERNIGHT...BETTER SEVERE THREAT ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
AMPLIFIED PATTERN WILL CONTINUE TO PUMP GULF MOISTURE INTO NORTHERN
MICHIGAN THROUGH WEDNESDAY...PROVIDING CHANCES FOR RAIN AND
THUNDERSTORMS. THUNDERSTORM KINEMATICS ARE GREAT TUESDAY AFTERNOON.
ALTHOUGH IF THERE IS LINGERING CLOUDS FROM TONIGHT AND EARLY TUESDAY
MORNING/S CONVECTION...DIURNAL HEATING MAY BE VERY
MINIMAL...HINDERING ATMOSPHERIC DESTABILIZATION NEEDED FOR
THUNDERSTORM DEVELOPMENT. THERE WILL BE A COOL DOWN ONCE
THIS SLOW MOVING AMPLIFIED TROUGH MOVES THROUGH THE GREAT LAKES
REGION WITH CHILLY FRIDAY AND SATURDAY MORNINGS AND MAX TEMPERATURES
ONLY REACHING INTO THE MID 50S TO MID 60S THURSDAY AND RIGHT ON
THROUGH THE MEMORIAL DAY WEEKEND.
TUESDAY MORNING THROUGH WEDNESDAY NIGHT...ANY LINGERING PATCHY FOG
WILL DIMINISH IN THE EARLY MORNING HOURS. IN DAY 2 SLIGHT RISK FROM
SPC. SO THE BIG QUESTION IS...WILL THE SUN BREAK OUT OVER NORTHERN
MICHIGAN TUESDAY BEHIND TONIGHT/S CONVECTION? THE INGREDIENTS FOR
STRONG/SEVERE THUNDERSTORMS ARE MOST CERTAINLY THERE WITH SFC DEW
POINTS FORECAST TO BE IN THE UPPER 50S TO LOW 60S...GOOD LOW TO
MID-LEVEL DIRECTIONAL SHEAR...0-6KM BULK SHEAR 50-60 KTS...GOOD JET
DYNAMICS AND MLCAPE 1100 J/KG WITH VERY MINIMAL MLCINH. WITH THE
0-6KM BULK SHEAR VECTORS AT A 45 DEGREE ANGLE TO THE EAST-WEST
ORIENTED BOUNDARY LAYER DRAPED OVER NORTHERN LOWER MICHIGAN...ANY
STORMS THAT DO DEVELOP SHOULD BE CELLULAR AT FIRST AND CHANGE TO
LINEAR WITH TIME. WITH -10 TO -30C CAPE OF 500-600 J/KG AND LAPSE
RATES BETWEEN 6.5-7 C/KM...HAIL WILL BE A THREAT WITH ANY STORM THAT
DOES DEVELOP. OF COURSE LOCATION WILL PROBABLY CHANGE BY
TOMORROW...BUT AS OF RIGHT NOW OUR SOUTHERN CWA SEEMS TO BE THE
FAVORED AREA TOMORROW FOR THUNDERSTORM ACTIVITY.
WEDNESDAY...ALTHOUGH THUNDERSTORMS ARE ONCE AGAIN POSSIBLE WEDNESDAY
AFTERNOON THE SEVERE THREAT SHOULD BE GONE. DIURNAL HEATING WILL
PRODUCE CHANCES OF RAIN AND THUNDERSTORMS WEDNESDAY AFTERNOON. STILL
TAPPED INTO GULF MOISTURE WITH PWAT VALUES ABOVE 1.00 INCH AND
AROUND 1000 J/KG OF SKINNY CAPE...EXPECT ANY RAIN OR THUNDERSTORMS
THAT DO DEVELOP TO PRODUCE HEAVY RAIN.
THURSDAY...LOW PRESSURE CENTER MOVES DIRECTLY OVER
MICHIGAN...PRODUCING RAIN WHICH MAY BE HEAVY AT TIMES. AS THE LOW
PRESSURE CENTER FINALLY BEGINS TO MOVE OFF TO THE EAST...A LARGE
HIGH PRESSURE CENTER OVER WESTERN CANADA BUILDS INTO THE
REGION...ENDING PRECIPITATION FROM NORTHWEST TO SOUTHEAST BEGINNING
IN THE EARLY AFTERNOON HOURS AS MUCH DRIER AND COOLER AIR MOVES IN
OVER NORTHERN MICHIGAN.
MEMORIAL DAY WEEKEND (FRIDAY THROUGH MONDAY)...DRY FORECAST FOR THE
EXTENDED HOLIDAY WEEKEND WITH A LARGE AREA OF HIGH PRESSURE
CONTINUING TO BUILD OVER THE GREAT LAKES REGION. COOLER...WITH
TEMPERATURES ONLY REACHING INTO THE 60S. FROST IS POSSIBLE FRIDAY
AND SATURDAY MORNING...ALTHOUGH MODELS HAVE BEEN TRENDING SOMEWHAT
WARMER. LEFT INHERITED FROST IN THE GRIDS FOR SATURDAY MORNING UNTIL
MORE CONFIDENCE IS ACHIEVED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1201 AM EDT TUE MAY 21 2013
NEARLY STATIONARY BOUNDARY CONTINUES TO DISSECT THE TAF SITES
FROM NORTHWEST TO SOUTHEAST. THIS IS EXPECTED TO KEEP PLN AND APN
IN THE LOW CLOUDS AND FOG...DENSE AT APN OVERNIGHT WITH PATCHY FOG
AT TVC AND MBL. ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO MOVE INTO MBL AND TVC EARLY THIS MORNING AND SPREAD INTO PLN
AND APN LATE. MORE SHOWERS AND THUNDERSTORMS ARE LIKELY DURING THE
DAY AS WELL.
&&
.MARINE...
ISSUED AT 402 PM EDT MON MAY 20 2013
SOME GUSTINESS WILL BE FELT ON THE LAKES INTO THE EVENING WITH A
FEW GUSTS INTO THE 20 TO 25 KNOT RANGE. BUT WINDS DIMINISH TONIGHT
AND REMAIN ON THE LIGHTER SIDE THROUGH WEDNESDAY AS AN AREA OF
LOW PRESSURE SLOWLY WORKS THROUGH THE REGION.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...AS
SYNOPSIS...SR
SHORT TERM...BA
LONG TERM...TL
AVIATION...AS
MARINE...BA
000
FXUS63 KAPX 210217
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1017 PM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 402 PM EDT MON MAY 20 2013
A STORM SYSTEM IN THE PLAINS WILL MOVE INTO THE GREAT LAKES THIS
WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF THE REGION THURSDAY.
THIS PATTERN WILL SET THE STAGE FOR CONTINUED MILD TEMPERATURES...
ALONG WITH SEVERAL CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.UPDATE...
ISSUED AT 949 PM EDT MON MAY 20 2013
THE WARM AND HUMID AIRMASS IN COMBINATION WITH LIGHT WINDS AND LOW
LEVEL MOISTURE FROM THE RAIN THAT FELL EARLIER TODAY HAS LED TO
FOG FORMATION ACROSS PORTIONS OF THE FORECAST AREA. THE FOG IS
DENSE IN A COUPLE OF SPOTS AS WELL. WILL HAVE TO MONITOR LATEST
TRENDS ON THIS ONE TO SEE IF THE FOG BECOMES WIDESPREAD OVERNIGHT.
MEANWHILE...THE NEXT SPOKE OF ENERGY ROTATING AROUND LARGE UPPER
LOW CENTERED OVER MINNESOTA IS MOVING UP ACROSS ILLINOIS. IN
ADDITION...SURFACE WARM FRONT CONTINUES TO BE DRAPED FROM NEAR
CHARLEVOIX TO JUST NORTH OF OSCODA. THEREFORE...SHOWER AND
THUNDERSTORM ACTIVITY ASSOCIATED WITH THE UPPER LEVEL FEATURE IS
EXPECTED TO ARRIVE ACROSS SOUTHWESTERN PORTIONS OF THE FORECAST
AREA LATE OVERNIGHT. ACTIVITY SHOULD THEN SPREAD NORTHEAST AS
ANOTHER THETA-E RIDGE BUILDS IN AND COMBINES WITH A STRENGTHENING
LOW LEVEL JET. AT THIS POINT AM NOT EXPECTED SEVERE STORMS AS
OVERALL INSTABILITY IS MINIMAL...THOUGH IT CAN NOT BE TOTALLY
RULED OUT WITH EFFECTIVE BULK SHEAR OF 35 TO 40 KNOTS AND MOST
UNSTABLE CAPE NEAR 1000 J/KG.
UPDATE ISSUED AT 741 PM EDT MON MAY 20 2013
FIRST ROUND OF CONVECTION NOW TO THE EAST OF THE FORECAST AREA
WITH SATELLITE/RADAR/SURFACE DATA SUGGESTING A BREAK IN THE ACTION OVER
THE NEXT FEW HOURS AT A MINIMUM. MODELS ARE BRINGING ANOTHER ROUND
OF SHOWERS AND THUNDERSTORMS BACK INTO THE REGION OVERNIGHT...SO
THAT WILL BE THE MAIN CHALLENGE OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
OVERVIEW: SPLIT FLOW PATTERN ACROSS THE CONUS WITH A BROAD CLOSED
TROUGH IN THE PLAINS CENTERED OVER THE EASTERN DAKOTAS. STRONG
IMPULSE ROTATING AROUND THE EASTERN FLANK OF THE LOW NOW PRESSING UP
INTO THE WESTERN GREAT LAKES. ACTING ON DECENT INSTABILITY AXIS
STRETCHED UP THROUGH NRN LOWER MICHIGAN (MLCAPE VALUES RUNNING
UPWARD OF 1500 J/KG)...PRODUCING A THIN CORRIDOR OF STORMS ADVANCING
THROUGH THE REGION. A FEW SEVERE HAIL REPORTS AND GUSTS OF 40 TO 50
MPH...BUT OVERALL EVENT IS A LITTLE DISAPPOINTING...SO FAR.
TONIGHT...LINE OF STORMS LOOKING TO ADVANCE OUT OF THE CWA BY EARLY
EVENING WITH A WEDGE OF DRIER AIR/SUBSIDENCE/NO PRECIP BUILDING INTO
THE AREA FOR THE BULK OF THE EVENING. WINDS WEAKEN...AND WITH THE
AFTERNOON RAINFALL...A PRETTY GOOD SETUP FOR DEVELOPMENT OF SOME LOW
CLOUDS AND FOG AS WE GO THROUGH THE EVENING.
THEN...FORECAST A BIT MORE NEBULOUS OVERNIGHT INTO TUESDAY. LOW
PRESSURE IN THE NRN PLAINS TODAY SLOWLY DRIFTS EASTWARD INTO THE
WESTERN GREAT LAKES WITH THE SFC FRONT REMAINING STRETCHED OUT INTO
LOWER MICHIGAN. STILL A DECENT SIGNAL THAT WE SEE RENEWED CONVECTIVE
DEVELOPMENT ALONG THAT FRONT LATER TONIGHT AS THE LOW LEVEL JET
INCREASES AND SO WILL CONTINUE WITH OUR GOING FORECAST OF LIKELY
POPS ADVANCING WEST-EAST INTO THE CWA DURING THE OVERNIGHT PERIOD.
LOW SEVERE THREAT OVERNIGHT...BETTER SEVERE THREAT ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
AMPLIFIED PATTERN WILL CONTINUE TO PUMP GULF MOISTURE INTO NORTHERN
MICHIGAN THROUGH WEDNESDAY...PROVIDING CHANCES FOR RAIN AND
THUNDERSTORMS. THUNDERSTORM KINEMATICS ARE GREAT TUESDAY AFTERNOON.
ALTHOUGH IF THERE IS LINGERING CLOUDS FROM TONIGHT AND EARLY TUESDAY
MORNING/S CONVECTION...DIURNAL HEATING MAY BE VERY
MINIMAL...HINDERING ATMOSPHERIC DESTABILIZATION NEEDED FOR
THUNDERSTORM DEVELOPMENT. THERE WILL BE A COOL DOWN ONCE
THIS SLOW MOVING AMPLIFIED TROUGH MOVES THROUGH THE GREAT LAKES
REGION WITH CHILLY FRIDAY AND SATURDAY MORNINGS AND MAX TEMPERATURES
ONLY REACHING INTO THE MID 50S TO MID 60S THURSDAY AND RIGHT ON
THROUGH THE MEMORIAL DAY WEEKEND.
TUESDAY MORNING THROUGH WEDNESDAY NIGHT...ANY LINGERING PATCHY FOG
WILL DIMINISH IN THE EARLY MORNING HOURS. IN DAY 2 SLIGHT RISK FROM
SPC. SO THE BIG QUESTION IS...WILL THE SUN BREAK OUT OVER NORTHERN
MICHIGAN TUESDAY BEHIND TONIGHT/S CONVECTION? THE INGREDIENTS FOR
STRONG/SEVERE THUNDERSTORMS ARE MOST CERTAINLY THERE WITH SFC DEW
POINTS FORECAST TO BE IN THE UPPER 50S TO LOW 60S...GOOD LOW TO
MID-LEVEL DIRECTIONAL SHEAR...0-6KM BULK SHEAR 50-60 KTS...GOOD JET
DYNAMICS AND MLCAPE 1100 J/KG WITH VERY MINIMAL MLCINH. WITH THE
0-6KM BULK SHEAR VECTORS AT A 45 DEGREE ANGLE TO THE EAST-WEST
ORIENTED BOUNDARY LAYER DRAPED OVER NORTHERN LOWER MICHIGAN...ANY
STORMS THAT DO DEVELOP SHOULD BE CELLULAR AT FIRST AND CHANGE TO
LINEAR WITH TIME. WITH -10 TO -30C CAPE OF 500-600 J/KG AND LAPSE
RATES BETWEEN 6.5-7 C/KM...HAIL WILL BE A THREAT WITH ANY STORM THAT
DOES DEVELOP. OF COURSE LOCATION WILL PROBABLY CHANGE BY
TOMORROW...BUT AS OF RIGHT NOW OUR SOUTHERN CWA SEEMS TO BE THE
FAVORED AREA TOMORROW FOR THUNDERSTORM ACTIVITY.
WEDNESDAY...ALTHOUGH THUNDERSTORMS ARE ONCE AGAIN POSSIBLE WEDNESDAY
AFTERNOON THE SEVERE THREAT SHOULD BE GONE. DIURNAL HEATING WILL
PRODUCE CHANCES OF RAIN AND THUNDERSTORMS WEDNESDAY AFTERNOON. STILL
TAPPED INTO GULF MOISTURE WITH PWAT VALUES ABOVE 1.00 INCH AND
AROUND 1000 J/KG OF SKINNY CAPE...EXPECT ANY RAIN OR THUNDERSTORMS
THAT DO DEVELOP TO PRODUCE HEAVY RAIN.
THURSDAY...LOW PRESSURE CENTER MOVES DIRECTLY OVER
MICHIGAN...PRODUCING RAIN WHICH MAY BE HEAVY AT TIMES. AS THE LOW
PRESSURE CENTER FINALLY BEGINS TO MOVE OFF TO THE EAST...A LARGE
HIGH PRESSURE CENTER OVER WESTERN CANADA BUILDS INTO THE
REGION...ENDING PRECIPITATION FROM NORTHWEST TO SOUTHEAST BEGINNING
IN THE EARLY AFTERNOON HOURS AS MUCH DRIER AND COOLER AIR MOVES IN
OVER NORTHERN MICHIGAN.
MEMORIAL DAY WEEKEND (FRIDAY THROUGH MONDAY)...DRY FORECAST FOR THE
EXTENDED HOLIDAY WEEKEND WITH A LARGE AREA OF HIGH PRESSURE
CONTINUING TO BUILD OVER THE GREAT LAKES REGION. COOLER...WITH
TEMPERATURES ONLY REACHING INTO THE 60S. FROST IS POSSIBLE FRIDAY
AND SATURDAY MORNING...ALTHOUGH MODELS HAVE BEEN TRENDING SOMEWHAT
WARMER. LEFT INHERITED FROST IN THE GRIDS FOR SATURDAY MORNING UNTIL
MORE CONFIDENCE IS ACHIEVED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 741 PM EDT MON MAY 20 2013
FIRST ROUND OF SHOWERS AND THUNDERSTORMS NOW EAST OF ALL TAF
SITES. NEARLY STATIONARY BOUNDARY DISSECTS THE TAF SITES FROM
NORTHWEST TO SOUTHEAST. THIS IS EXPECTED TO KEEP PLN AND APN IN
THE LOW CLOUDS AND FOG OVERNIGHT WITH FOG POSSIBLY FORMING AFTER
MIDNIGHT AT TVC AND MBL. ADDITIONAL SHOWERS AND POSSIBLY
THUNDERSTORMS MAY DEVELOP OVERNIGHT AS WELL...WITH A BETTER CHANCE
OF OCCURRENCE DURING THE DAY ON TUESDAY.
&&
.MARINE...
ISSUED AT 402 PM EDT MON MAY 20 2013
SOME GUSTINESS WILL BE FELT ON THE LAKES INTO THE EVENING WITH A
FEW GUSTS INTO THE 20 TO 25 KNOT RANGE. BUT WINDS DIMINISH TONIGHT
AND REMAIN ON THE LIGHTER SIDE THROUGH WEDNESDAY AS AN AREA OF
LOW PRESSURE SLOWLY WORKS THROUGH THE REGION.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...AS
SYNOPSIS...SR
SHORT TERM...BA
LONG TERM...TL
AVIATION...AS
MARINE...BA
000
FXUS63 KAPX 202347
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
747 PM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 402 PM EDT MON MAY 20 2013
A STORM SYSTEM IN THE PLAINS WILL MOVE INTO THE GREAT LAKES THIS
WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF THE REGION THURSDAY.
THIS PATTERN WILL SET THE STAGE FOR CONTINUED MILD TEMPERATURES...
ALONG WITH SEVERAL CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.UPDATE...
ISSUED AT 741 PM EDT MON MAY 20 2013
FIRST ROUND OF CONVECTION NOW TO THE EAST OF THE FORECAST AREA
WITH SATELLITE/RADAR/SURFACE DATA SUGGESTING A BREAK IN THE ACTION OVER
THE NEXT FEW HOURS AT A MINIMUM. MODELS ARE BRINGING ANOTHER ROUND
OF SHOWERS AND THUNDERSTORMS BACK INTO THE REGION OVERNIGHT...SO
THAT WILL BE THE MAIN CHALLENGE OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
OVERVIEW: SPLIT FLOW PATTERN ACROSS THE CONUS WITH A BROAD CLOSED
TROUGH IN THE PLAINS CENTERED OVER THE EASTERN DAKOTAS. STRONG
IMPULSE ROTATING AROUND THE EASTERN FLANK OF THE LOW NOW PRESSING UP
INTO THE WESTERN GREAT LAKES. ACTING ON DECENT INSTABILITY AXIS
STRETCHED UP THROUGH NRN LOWER MICHIGAN (MLCAPE VALUES RUNNING
UPWARD OF 1500 J/KG)...PRODUCING A THIN CORRIDOR OF STORMS ADVANCING
THROUGH THE REGION. A FEW SEVERE HAIL REPORTS AND GUSTS OF 40 TO 50
MPH...BUT OVERALL EVENT IS A LITTLE DISAPPOINTING...SO FAR.
TONIGHT...LINE OF STORMS LOOKING TO ADVANCE OUT OF THE CWA BY EARLY
EVENING WITH A WEDGE OF DRIER AIR/SUBSIDENCE/NO PRECIP BUILDING INTO
THE AREA FOR THE BULK OF THE EVENING. WINDS WEAKEN...AND WITH THE
AFTERNOON RAINFALL...A PRETTY GOOD SETUP FOR DEVELOPMENT OF SOME LOW
CLOUDS AND FOG AS WE GO THROUGH THE EVENING.
THEN...FORECAST A BIT MORE NEBULOUS OVERNIGHT INTO TUESDAY. LOW
PRESSURE IN THE NRN PLAINS TODAY SLOWLY DRIFTS EASTWARD INTO THE
WESTERN GREAT LAKES WITH THE SFC FRONT REMAINING STRETCHED OUT INTO
LOWER MICHIGAN. STILL A DECENT SIGNAL THAT WE SEE RENEWED CONVECTIVE
DEVELOPMENT ALONG THAT FRONT LATER TONIGHT AS THE LOW LEVEL JET
INCREASES AND SO WILL CONTINUE WITH OUR GOING FORECAST OF LIKELY
POPS ADVANCING WEST-EAST INTO THE CWA DURING THE OVERNIGHT PERIOD.
LOW SEVERE THREAT OVERNIGHT...BETTER SEVERE THREAT ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
AMPLIFIED PATTERN WILL CONTINUE TO PUMP GULF MOISTURE INTO NORTHERN
MICHIGAN THROUGH WEDNESDAY...PROVIDING CHANCES FOR RAIN AND
THUNDERSTORMS. THUNDERSTORM KINEMATICS ARE GREAT TUESDAY AFTERNOON.
ALTHOUGH IF THERE IS LINGERING CLOUDS FROM TONIGHT AND EARLY TUESDAY
MORNING/S CONVECTION...DIURNAL HEATING MAY BE VERY
MINIMAL...HINDERING ATMOSPHERIC DESTABILIZATION NEEDED FOR
THUNDERSTORM DEVELOPMENT. THERE WILL BE A COOL DOWN ONCE
THIS SLOW MOVING AMPLIFIED TROUGH MOVES THROUGH THE GREAT LAKES
REGION WITH CHILLY FRIDAY AND SATURDAY MORNINGS AND MAX TEMPERATURES
ONLY REACHING INTO THE MID 50S TO MID 60S THURSDAY AND RIGHT ON
THROUGH THE MEMORIAL DAY WEEKEND.
TUESDAY MORNING THROUGH WEDNESDAY NIGHT...ANY LINGERING PATCHY FOG
WILL DIMINISH IN THE EARLY MORNING HOURS. IN DAY 2 SLIGHT RISK FROM
SPC. SO THE BIG QUESTION IS...WILL THE SUN BREAK OUT OVER NORTHERN
MICHIGAN TUESDAY BEHIND TONIGHT/S CONVECTION? THE INGREDIENTS FOR
STRONG/SEVERE THUNDERSTORMS ARE MOST CERTAINLY THERE WITH SFC DEW
POINTS FORECAST TO BE IN THE UPPER 50S TO LOW 60S...GOOD LOW TO
MID-LEVEL DIRECTIONAL SHEAR...0-6KM BULK SHEAR 50-60 KTS...GOOD JET
DYNAMICS AND MLCAPE 1100 J/KG WITH VERY MINIMAL MLCINH. WITH THE
0-6KM BULK SHEAR VECTORS AT A 45 DEGREE ANGLE TO THE EAST-WEST
ORIENTED BOUNDARY LAYER DRAPED OVER NORTHERN LOWER MICHIGAN...ANY
STORMS THAT DO DEVELOP SHOULD BE CELLULAR AT FIRST AND CHANGE TO
LINEAR WITH TIME. WITH -10 TO -30C CAPE OF 500-600 J/KG AND LAPSE
RATES BETWEEN 6.5-7 C/KM...HAIL WILL BE A THREAT WITH ANY STORM THAT
DOES DEVELOP. OF COURSE LOCATION WILL PROBABLY CHANGE BY
TOMORROW...BUT AS OF RIGHT NOW OUR SOUTHERN CWA SEEMS TO BE THE
FAVORED AREA TOMORROW FOR THUNDERSTORM ACTIVITY.
WEDNESDAY...ALTHOUGH THUNDERSTORMS ARE ONCE AGAIN POSSIBLE WEDNESDAY
AFTERNOON THE SEVERE THREAT SHOULD BE GONE. DIURNAL HEATING WILL
PRODUCE CHANCES OF RAIN AND THUNDERSTORMS WEDNESDAY AFTERNOON. STILL
TAPPED INTO GULF MOISTURE WITH PWAT VALUES ABOVE 1.00 INCH AND
AROUND 1000 J/KG OF SKINNY CAPE...EXPECT ANY RAIN OR THUNDERSTORMS
THAT DO DEVELOP TO PRODUCE HEAVY RAIN.
THURSDAY...LOW PRESSURE CENTER MOVES DIRECTLY OVER
MICHIGAN...PRODUCING RAIN WHICH MAY BE HEAVY AT TIMES. AS THE LOW
PRESSURE CENTER FINALLY BEGINS TO MOVE OFF TO THE EAST...A LARGE
HIGH PRESSURE CENTER OVER WESTERN CANADA BUILDS INTO THE
REGION...ENDING PRECIPITATION FROM NORTHWEST TO SOUTHEAST BEGINNING
IN THE EARLY AFTERNOON HOURS AS MUCH DRIER AND COOLER AIR MOVES IN
OVER NORTHERN MICHIGAN.
MEMORIAL DAY WEEKEND (FRIDAY THROUGH MONDAY)...DRY FORECAST FOR THE
EXTENDED HOLIDAY WEEKEND WITH A LARGE AREA OF HIGH PRESSURE
CONTINUING TO BUILD OVER THE GREAT LAKES REGION. COOLER...WITH
TEMPERATURES ONLY REACHING INTO THE 60S. FROST IS POSSIBLE FRIDAY
AND SATURDAY MORNING...ALTHOUGH MODELS HAVE BEEN TRENDING SOMEWHAT
WARMER. LEFT INHERITED FROST IN THE GRIDS FOR SATURDAY MORNING UNTIL
MORE CONFIDENCE IS ACHIEVED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 741 PM EDT MON MAY 20 2013
FIRST ROUND OF SHOWERS AND THUNDERSTORMS NOW EAST OF ALL TAF
SITES. NEARLY STATIONARY BOUNDARY DISSECTS THE TAF SITES FROM
NORTHWEST TO SOUTHEAST. THIS IS EXPECTED TO KEEP PLN AND APN IN
THE LOW CLOUDS AND FOG OVERNIGHT WITH FOG POSSIBLY FORMING AFTER
MIDNIGHT AT TVC AND MBL. ADDITIONAL SHOWERS AND POSSIBLY
THUNDERSTORMS MAY DEVELOP OVERNIGHT AS WELL...WITH A BETTER CHANCE
OF OCCURRENCE DURING THE DAY ON TUESDAY.
&&
.MARINE...
ISSUED AT 402 PM EDT MON MAY 20 2013
SOME GUSTINESS WILL BE FELT ON THE LAKES INTO THE EVENING WITH A
FEW GUSTS INTO THE 20 TO 25 KNOT RANGE. BUT WINDS DIMINISH TONIGHT
AND REMAIN ON THE LIGHTER SIDE THROUGH WEDNESDAY AS AN AREA OF
LOW PRESSURE SLOWLY WORKS THROUGH THE REGION.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...AS
SYNOPSIS...SR
SHORT TERM...BA
LONG TERM...TL
AVIATION...AS
MARINE...BA
000
FXUS63 KAPX 202005
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
405 PM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 402 PM EDT MON MAY 20 2013
A STORM SYSTEM IN THE PLAINS WILL MOVE INTO THE GREAT LAKES THIS
WEEK. THE STORM SYSTEM WILL EVENTUALLY EXIT EAST OF THE REGION THURSDAY.
THIS PATTERN WILL SET THE STAGE FOR CONTINUED MILD TEMPERATURES...
ALONG WITH SEVERAL CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
MIDWEEK.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FRIDAY AND SATURDAY.
THIS PATTERN WILL GENERATE PLENTY OF SUN AND SEASONAL
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH THE UPCOMING HOLIDAY
WEEKEND.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
OVERVIEW: SPLIT FLOW PATTERN ACROSS THE CONUS WITH A BROAD CLOSED
TROUGH IN THE PLAINS CENTERED OVER THE EASTERN DAKOTAS. STRONG
IMPULSE ROTATING AROUND THE EASTERN FLANK OF THE LOW NOW PRESSING UP
INTO THE WESTERN GREAT LAKES. ACTING ON DECENT INSTABILITY AXIS
STRETCHED UP THROUGH NRN LOWER MICHIGAN (MLCAPE VALUES RUNNING
UPWARD OF 1500 J/KG)...PRODUCING A THIN CORRIDOR OF STORMS ADVANCING
THROUGH THE REGION. A FEW SEVERE HAIL REPORTS AND GUSTS OF 40 TO 50
MPH...BUT OVERALL EVENT IS A LITTLE DISAPPOINTING...SO FAR.
TONIGHT...LINE OF STORMS LOOKING TO ADVANCE OUT OF THE CWA BY EARLY
EVENING WITH A WEDGE OF DRIER AIR/SUBSIDENCE/NO PRECIP BUILDING INTO
THE AREA FOR THE BULK OF THE EVENING. WINDS WEAKEN...AND WITH THE
AFTERNOON RAINFALL...A PRETTY GOOD SETUP FOR DEVELOPMENT OF SOME LOW
CLOUDS AND FOG AS WE GO THROUGH THE EVENING.
THEN...FORECAST A BIT MORE NEBULOUS OVERNIGHT INTO TUESDAY. LOW
PRESSURE IN THE NRN PLAINS TODAY SLOWLY DRIFTS EASTWARD INTO THE
WESTERN GREAT LAKES WITH THE SFC FRONT REMAINING STRETCHED OUT INTO
LOWER MICHIGAN. STILL A DECENT SIGNAL THAT WE SEE RENEWED CONVECTIVE
DEVELOPMENT ALONG THAT FRONT LATER TONIGHT AS THE LOW LEVEL JET
INCREASES AND SO WILL CONTINUE WITH OUR GOING FORECAST OF LIKELY
POPS ADVANCING WEST-EAST INTO THE CWA DURING THE OVERNIGHT PERIOD.
LOW SEVERE THREAT OVERNIGHT...BETTER SEVERE THREAT ON TUESDAY.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 402 PM EDT MON MAY 20 2013
AMPLIFIED PATTERN WILL CONTINUE TO PUMP GULF MOISTURE INTO NORTHERN
MICHIGAN THROUGH WEDNESDAY...PROVIDING CHANCES FOR RAIN AND
THUNDERSTORMS. THUNDERSTORM KINEMATICS ARE GREAT TUESDAY AFTERNOON.
ALTHOUGH IF THERE IS LINGERING CLOUDS FROM TONIGHT AND EARLY TUESDAY
MORNING/S CONVECTION...DIURNAL HEATING MAY BE VERY
MINIMAL...HINDERING ATMOSPHERIC DESTABILIZATION NEEDED FOR
THUNDERSTORM DEVELOPMENT. THERE WILL BE A COOL DOWN ONCE
THIS SLOW MOVING AMPLIFIED TROUGH MOVES THROUGH THE GREAT LAKES
REGION WITH CHILLY FRIDAY AND SATURDAY MORNINGS AND MAX TEMPERATURES
ONLY REACHING INTO THE MID 50S TO MID 60S THURSDAY AND RIGHT ON
THROUGH THE MEMORIAL DAY WEEKEND.
TUESDAY MORNING THROUGH WEDNESDAY NIGHT...ANY LINGERING PATCHY FOG
WILL DIMINISH IN THE EARLY MORNING HOURS. IN DAY 2 SLIGHT RISK FROM
SPC. SO THE BIG QUESTION IS...WILL THE SUN BREAK OUT OVER NORTHERN
MICHIGAN TUESDAY BEHIND TONIGHT/S CONVECTION? THE INGREDIENTS FOR
STRONG/SEVERE THUNDERSTORMS ARE MOST CERTAINLY THERE WITH SFC DEW
POINTS FORECAST TO BE IN THE UPPER 50S TO LOW 60S...GOOD LOW TO
MID-LEVEL DIRECTIONAL SHEAR...0-6KM BULK SHEAR 50-60 KTS...GOOD JET
DYNAMICS AND MLCAPE 1100 J/KG WITH VERY MINIMAL MLCINH. WITH THE
0-6KM BULK SHEAR VECTORS AT A 45 DEGREE ANGLE TO THE EAST-WEST
ORIENTED BOUNDARY LAYER DRAPED OVER NORTHERN LOWER MICHIGAN...ANY
STORMS THAT DO DEVELOP SHOULD BE CELLULAR AT FIRST AND CHANGE TO
LINEAR WITH TIME. WITH -10 TO -30C CAPE OF 500-600 J/KG AND LAPSE
RATES BETWEEN 6.5-7 C/KM...HAIL WILL BE A THREAT WITH ANY STORM THAT
DOES DEVELOP. OF COURSE LOCATION WILL PROBABLY CHANGE BY
TOMORROW...BUT AS OF RIGHT NOW OUR SOUTHERN CWA SEEMS TO BE THE
FAVORED AREA TOMORROW FOR THUNDERSTORM ACTIVITY.
WEDNESDAY...ALTHOUGH THUNDERSTORMS ARE ONCE AGAIN POSSIBLE WEDNESDAY
AFTERNOON THE SEVERE THREAT SHOULD BE GONE. DIURNAL HEATING WILL
PRODUCE CHANCES OF RAIN AND THUNDERSTORMS WEDNESDAY AFTERNOON. STILL
TAPPED INTO GULF MOISTURE WITH PWAT VALUES ABOVE 1.00 INCH AND
AROUND 1000 J/KG OF SKINNY CAPE...EXPECT ANY RAIN OR THUNDERSTORMS
THAT DO DEVELOP TO PRODUCE HEAVY RAIN.
THURSDAY...LOW PRESSURE CENTER MOVES DIRECTLY OVER
MICHIGAN...PRODUCING RAIN WHICH MAY BE HEAVY AT TIMES. AS THE LOW
PRESSURE CENTER FINALLY BEGINS TO MOVE OFF TO THE EAST...A LARGE
HIGH PRESSURE CENTER OVER WESTERN CANADA BUILDS INTO THE
REGION...ENDING PRECIPITATION FROM NORTHWEST TO SOUTHEAST BEGINNING
IN THE EARLY AFTERNOON HOURS AS MUCH DRIER AND COOLER AIR MOVES IN
OVER NORTHERN MICHIGAN.
MEMORIAL DAY WEEKEND (FRIDAY THROUGH MONDAY)...DRY FORECAST FOR THE
EXTENDED HOLIDAY WEEKEND WITH A LARGE AREA OF HIGH PRESSURE
CONTINUING TO BUILD OVER THE GREAT LAKES REGION. COOLER...WITH
TEMPERATURES ONLY REACHING INTO THE 60S. FROST IS POSSIBLE FRIDAY
AND SATURDAY MORNING...ALTHOUGH MODELS HAVE BEEN TRENDING SOMEWHAT
WARMER. LEFT INHERITED FROST IN THE GRIDS FOR SATURDAY MORNING UNTIL
MORE CONFIDENCE IS ACHIEVED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 217 PM EDT MON MAY 20 2013
THIN LINE OF STRONG STORMS WILL SWING THROUGH NRN LOWER MICHIGAN
OVER THE NEXT 4 HOURS OR SO...IMPACTING TVC FIRST...THEN
ULTIMATELY PLN AND APN AS WE GO THROUGH THE AFTERNOON HOURS. IFR
CONDITIONS LOCKED IN AT APN CURRENTLY...BUT THINK STRATUS WILL MIX
OUT WITHIN ANOTHER HOUR OR TWO LEAVING A PERIOD OF VFR WEATHER
BEFORE STORMS ARRIVE.
LINE EXITS NRN LOWER MICHIGAN THIS EVENING AND WOULD EXPECT SOME
FOG DEVELOPMENT WITH MVFR OR EVEN IFR CONDITIONS AS WINDS WEAKEN
AND WITH THE AFTERNOON RAINS. ANOTHER ROUND OF SHOWERS AND STORMS
MAY DEVELOP UPSTREAM LATER TONIGHT AND PUSH INTO NRN LOWER
MICHIGAN LATE OVERNIGHT THROUGH TUESDAY MORNING.
&&
.MARINE...
ISSUED AT 402 PM EDT MON MAY 20 2013
SOME GUSTINESS WILL BE FELT ON THE LAKES INTO THE EVENING WITH A
FEW GUSTS INTO THE 20 TO 25 KNOT RANGE. BUT WINDS DIMINISH TONIGHT
AND REMAIN ON THE LIGHTER SIDE THROUGH WEDNESDAY AS AN AREA OF
LOW PRESSURE SLOWLY WORKS THROUGH THE REGION.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...SEVERE THUNDERSTORM WATCH TIL 8 PM FOR MIC019-055-089-101-165
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...SR
SHORT TERM...BA
LONG TERM...TL
AVIATION...BA
MARINE...BA
000
FXUS63 KAPX 201818
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
218 PM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 953 AM EDT MON MAY 20 2013
A STORM SYSTEM ORGANIZING OVER THE PLAINS WILL SLOWLY MOVE ACROSS
THE GREAT LAKES REGION THROUGH MID-WEEK. THIS SYSTEM WILL GENERATE
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS ACROSS NORTHERN
MICHIGAN THROUGH WEDNESDAY NIGHT. DRY AND SEASONABLY COOL CONDITIONS
ARE EXPECTED FOR THE UPCOMING HOLIDAY WEEKEND.
&&
.UPDATE...
ISSUED AT 217 PM EDT MON MAY 20 2013
AXIS OF DECENT INSTABILITY STRETCHES UP THROUGH LOWER MICHIGAN
WITH MLCAPE VALUES EXCEEDING 2000 J/KG. COMBINED WITH MID LEVEL
IMPULSE PRESSING INTO THE WESTERN PART OF LOWER MICHIGAN AND
PERHAPS AIDED BY THE MARINE LAYER...THIN LINE OF STRONG TO SEVERE
STORMS NOW DEVELOPING UPSCALE ACROSS NW LOWER MICHIGAN. THIS WILL
OBVIOUSLY BE THE CASE FOR THE NEXT FEW HOURS AS IMPULSE SWINGS
THROUGH. BASED ON TRENDS AND WITH WEDGE OF DRIER AIR NOW FAR
BEHIND ACROSS EASTERN WISCONSIN...EVENT MAY BE OVER AROUND 6 PM OR
SO ALTHOUGH WATCH CURRENTLY RUNS THROUGH 8 PM.
UPDATE ISSUED AT 1100 AM EDT MON MAY 20 2013
HAVE MADE SOME CHANGES TO THE GOING FORECAST THIS AFTERNOON. FIRST
OFF...WARM FRONT CURRENTLY BISECTS NRN LOWER MICHIGAN WITH EASTERLY
FLOW FROM M-32 NORTHWARD. NORTH OF THE FRONT...MARINE STRATUS OFF
LAKE HURON HAS EXPANDED INTO NORTHEAST LOWER MICHIGAN/TIP OF THE
MITT AREA AND INTO THE STRAITS AND EASTERN UPPER MICHIGAN THIS
MORNING. FRONT NOT EXPECTED TO MOVE MUCH TODAY AND FEAR THAT
STRATUS WILL BE AN ISSUE FOR THE NRN PART OF THE CWA THROUGH THE
AFTERNOON AND PERHAPS EVEN THROUGH TONIGHT. HAVE TWEAKED FORECAST
TEMPS WAY DOWN FOR AREAS SUCH AS APN/PLN...ETC. HAVE ALSO TWEAKED
SKY COVER AND TAF FORECASTS TO MAINLY CLOUDY SKIES NORTH OF M-32.
WEATHER WISE...ONE BATCH OF SHOWERS AND A FEW STORMS PUSHING
NORTHEASTWARD OUT OF EASTERN UPPER MICHIGAN CURRENTLY. A FEW THIN
BANDS OF SHOWERS AND STORMS HAVE ALSO DEVELOPED IN THE LAST FEW
HOURS APPARENTLY ALONG EXISTING GRAVITY WAVES INTERACTING WITH
PLUME OF STEEP MID LEVEL LAPSE RATES CURRENTLY OVER THE REGION.
THESE SHOWERS/FEW STORMS WILL MOVE ON THROUGH THE ARE THROUGH THE
REST OF THE MORNING BEFORE STEEP LAPSE RATE PLUME PUSHES EAST OF
THE REGION.
FOR THE AFTERNOON INTO THE EVENING...OBVIOUSLY THE FRONT LOCATION
WILL BE A BIG PLAYER FOR TSTM DEVELOPMENT AND I DONT EXPECT IT TO
MOVE MUCH FROM ITS CURRENT LOCATION (DAYTIME HEATING MAY HELP TO
NUDGE IT NORTHWARD JUST A BIT...BUT TIP OF THE MITT MAY BE STUCK
INTO THE MUD ALL DAY). SOUTH OF THE FRONT...MODIFIED 12Z APX
SOUNDING WITH AFTERNOON TEMPS IN THE LOWER 80S AND SFC DEWPOINTS
IN THE LOWER 60S YIELDS AROUND 1500 J/KG MLCAPE VALUES ASSUMING WE
CAN MAINTAIN THOSE DEWPOINTS (ALREADY SEEING SOME CU DEVELOPMENT
DOWN AROUND CADILLAC). BUT WE ALSO HAVE A SUBTLE CAPPING LAYER
AROUND 750 MB AND IT/S UNCLEAR WHAT WILL HAPPEN IN THAT LAYER THIS
AFTERNOON. KICKER MAY BE THE MID LEVEL IMPULSE AND CORRIDOR OF
STRONGER WINDS ALOFT NOTED UPSTREAM OVER IOWA AND WILL PUSH UP
INTO EASTERN WISCONSIN/FAR WESTERN PART OF THE CWA LATER THIS
AFTERNOON...BRINGING SOME MODEST SYNOPTIC FORCING AS WELL AS
BETTER 0-6KM BULK SHEAR VALUES OF 30 TO 40 KNOTS FOR STORM
ORGANIZATION.
SO AT THIS POINT...THINK THUNDERSTORM DEVELOPMENT IS LIKELY LATER
THIS AFTERNOON EITHER UPSTREAM AND MOVING INTO THE REGION FROM THE
SW OR DEVELOPING OVER THE SRN TIER OF COUNTIES OF THIS CWA...OR
BOTH. ANY STORMS THAT DEVELOP WILL BE CAPABLE OF STRONG WINDS AND
HAIL. HAVE TO WATCH JUST WHERE THIS FRONT ENDS UP WITH RESULTING
BACKED FLOW AND ROTATING STORM POTENTIAL AS WELL.
UPDATE ISSUED AT 650 AM EDT MON MAY 20 2013
RESIDUAL AREA SHOWER AND STORMS HAS REACHED NRN LAKE MICHIGAN
EARLY THIS MORNING...AND AS GREATLY DIMINISHED IN BOTH INTENSITY
AND AREAL COVERAGE AS IT MOVES INTO THE MORE STABLE AND DRIER
AIRMASS OVER OUR CWA. THIS ARE OF CONVECTION WILL CLIP OUR
COUNTIES IN ERN UPR MICHIGAN BEFORE EXITING N/NE INTO ONTARIO...
CONTINUING TO DIMINISH AS IT DOES SO. CERTAINLY EXPECT PRECIP
CHANCES WILL INCREASE FROM WEST TO EAST THROUGHOUT THE DAY. HAVE
MADE SOME MINOR TIMING ADJUSTMENTS TO WX/POPS THIS MORNING BASED
ON RADAR TRENDS. SEVERAL LOCATIONS ARE STILL IN THE LOWER 60S THIS
MORNING...AND WE SHOULD HAVE NO PROBLEM REACHING WELL INTO THE 70S
AND LOWER 80S ACROSS NRN LWR MICHIGAN SOUTH OF THE STATIONARY
FRONT IN WAA PATTERN.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 323 AM EDT MON MAY 20 2013
CURRENTLY, SFC AND 500 MB LOWS IN THE PLAINS ARE BEGINNING TO STACK
UP WITH THE WARM FRONT EXTENDING ACROSS NORTHERN LOWER THIS MORNING,
THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS DROPS SOUTH INTO THE
SOUTHERN PLAINS AND INTO WEST TEXAS. ON THE KAPX RADAR, A FEW LIGHT
SHOWERS IN AND AROUND EASTERN UPPER, OTHERWISE, THE STORMS IN
WISCONSIN, ARE HEADING NNE AND AREN`T MAKING MUCH IN EASTWARD
PROGRESSION.
TODAY...WHILE THE GFS CONTINUES IT`S PRECIP BULL`S EYES OVER THE
FORECAST AREA, THE ECMWF CONTINUES TO SHOW A PATTERN OF ISOLATED
SHOWERS FOR THE MORNING WHILE LEAVING THE MAIN BULK OF THE THUNDER
IN WISCONSIN AND W UPPER. THE WARM FRONT OVER THE NEXT COUPLE OF
HOURS WILL MOVE NORTH THROUGH THE STRAITS LEAVING A CAPPED MOIST
LOWER LEVEL RIPE FOR THE AFTERNOON. THE MAIN PROBLEM WITH THE GFS
IDEA IS THE OVERLY AGGRESSIVE DEWPOINTS, WHICH IT HAS ALREADY IN THE
LOWER 60S. WHILE THE ECMWF HAS THE SFC DEWPOINTS IN THE UPPER 50S.
BASED ON THE TRAJECTORIES, NOT EXPECTING THE LOWER TO MID 60S
DEWPOINTS HERE UNTIL CLOSER TO 15Z. BY THE AFTERNOON, BOTH THE
MODELS HAVE THE 500 MB JET STREAK MOVING INTO NORTHERN LAKE
MICHIGAN. THIS INCREASES THE 0-6KM BULK SHEAR TO AROUND 40KTS. THE
ECMWF SHOWS A 500 M ML CAPE OF AROUND 1000 J/KG AT 18Z WHILE THE GFS
IS TWICE THIS, PROBABLY DUE TO THE SFC MOISTURE PROBLEMS NOTED BY
NCEP.
TONIGHT...THE MODELS CONTINUE THE HIGH 500 M ML CAPE VALUES INTO THE
EARLY EVENING. AS THE SFC HEATING SUBSIDES, THE EXPECTATION WILL BE
THAT THE SEVERE THREAT WILL DIMINISH. HOWEVER, WHILE THE INSTABILITY
WANES, THE MOISTURE WILL REMAIN HIGH WITH THE 500 MB JET STREAK OVER
THE REGION. THIS COULD CAUSE PROBLEMS WITH HEAVY RAIN AT TIMES.
WHILE I DON`T TRUST THE SFC MOISTURE IN THE GFS, EVEN IF YOU SCALE
BACK THE PWAT THERE IS STILL ABOUT 1" OR SO OF MOISTURE THERE. SO
CONTINUE THE LIKELY SHOWERS AND THUNDERSTORMS. ALTHOUGH THE THUNDER
SHOULD BECOME LESS AND LESS GOING INTO THE OVERNIGHT PERIOD.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM EDT MON MAY 20 2013
TUESDAY THRU WEDNESDAY...VERTICALLY STACKED LOW PRESSURE OVER THE
NRN PLAINS AND UPPER MISSISSIPPI VALLEY WILL BEGIN TO TAP INTO GULF
MOISTURE IN ERNEST ON TUESDAY...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. THIS
DEEPER MOISTURE WILL INTERACT WITH THE STATIONARY FRONT AND A SERIES
OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING UPPER
LOWER...LENDING TO CONTINUED DEVELOPMENT OF NUMEROUS SHOWERS AND
THUNDERSTORMS THRU WEDNESDAY. BROAD 850 MB THETA E RIDGING WILL HOLD
OVER MAINLY LWR MICHIGAN TUESDAY THRU WEDNESDAY...BUT LOW LEVEL JET
SOUTH OF MICHIGAN WILL LIKELY FOCUS STRONGER CONVECTION TO OUR
SOUTH. CERTAINLY CANNOT RULE OUT THE POSSIBILITY OF A FEW ISOLD
STRONGER/SVR STORMS THRU THIS PERIOD GIVEN DEEP MOISTURE AND GOOD
DYNAMICS. WILL MAINTAIN LIKELY POPS FOR OUR ENTIRE CWA TUESDAY THRU
WEDNESDAY NIGHT...WITH THUNDER CHANCES ENDING BY WEDNESDAY NIGHT AS
THE SURFACE LOW TRACKS RIGHT OVER OUR CWA. AFTER A RATHER WARM START
TO THE WORK WEEK...HIGH TEMPS WILL RANGE FROM AROUND 60 DEGREES IN
ERN UPR MICHIGAN NORTH OF THE FRONT TO THE UPPER 60S TO MID 70S IN
THE VCNTY OF THE FRONT IN NRN LWR MICHIGAN. LOW TEMPS TUESDAY NIGHT
WILL RANGE FROM THE UPPER 40S IN ERN UPR MICHIGAN TO AROUND 60 ALONG
OUR SRN COUNTIES. LOW TEMPS WEDNESDAY NIGHT WILL BE IN THE MID 40S
TO LOWER 50S.
AS WE HEAD INTO MEMORIAL DAY WEEKEND...THURSDAY THRU SUNDAY...
SLOWLY MORNING SURFACE AND UPPER LOW CENTERS WILL EXIT EAST TOWARD
NEW ENGLAND THURSDAY. SOME SHOWERS WILL LINGER ACROSS OUR CWA ON
THURSDAY...BUT SHOULD COME TO AN END BY THURSDAY NIGHT AS COLDER AND
DRIER AIR FILTER INTO THE REGION BEHIND THE DEPARTING LOW. COOL
CANADIAN HIGH PRESSURE WILL SETTLE INTO MICHIGAN FOR MEMORIAL
WEEKEND. CORE OF THE COLD AIR WILL REMAIN NE OF MICHIGAN...BUT
LIMITED CAA WILL DROP HIGH TEMPS INTO THE MID 50S TO TO LOWER 60S
FOR BOTH THURSDAY AND FRIDAY. THE WEEKEND STILL LOOKS DRY WITH
COOLER THAN NORMAL TEMPS AS THE SURFACE HIGH AND BROAD UPPER LEVEL
TROUGHING BOTH REMAIN LOCKED OVER THE GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 217 PM EDT MON MAY 20 2013
THIN LINE OF STRONG STORMS WILL SWING THROUGH NRN LOWER MICHIGAN
OVER THE NEXT 4 HOURS OR SO...IMPACTING TVC FIRST...THEN
ULTIMATELY PLN AND APN AS WE GO THROUGH THE AFTERNOON HOURS. IFR
CONDITIONS LOCKED IN AT APN CURRENTLY...BUT THINK STRATUS WILL MIX
OUT WITHIN ANOTHER HOUR OR TWO LEAVING A PERIOD OF VFR WEATHER
BEFORE STORMS ARRIVE.
LINE EXITS NRN LOWER MICHIGAN THIS EVENING AND WOULD EXPECT SOME
FOG DEVELOPMENT WITH MVFR OR EVEN IFR CONDITIONS AS WINDS WEAKEN
AND WITH THE AFTERNOON RAINS. ANOTHER ROUND OF SHOWERS AND STORMS
MAY DEVELOP UPSTREAM LATER TONIGHT AND PUSH INTO NRN LOWER
MICHIGAN LATE OVERNIGHT THROUGH TUESDAY MORNING.
&&
.MARINE...
ISSUED AT 323 AM EDT MON MAY 20 2013
IF THE WARM FRONT GETS NORTH OF THE FORECAST AREA, THEN THE ECMWF
IDEA OF THE SLACK GRADIENT THROUGH TODAY AND TONIGHT WILL BE RIGHT.
WHICH WILL KEEP THE WINDS BELOW SMALL CRAFT, AN IDEA THAT THE GFS
ALLOWS OVERNIGHT. HOWEVER, BY TUESDAY, THE GRADIENT WILL TIGHTEN AS
THE SFC LOW APPROACHES THE REGION. THIS COULD, WITH SOME COASTAL
CONVERGENCE, ALLOW THE WINDS TO GUST TO OVER SMALL CRAFT ADVISORY
CRITERIA FOR THE DAY, BUT AS THE SFC LOW DRAWS CLOSER, THE WINDS
WILL DIMINISH WITH THE SLACKENING GRADIENT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...BA
SYNOPSIS...MSB
SHORT TERM...JL
LONG TERM...MR
AVIATION...BA
MARINE...JL
000
FXUS63 KAPX 201501
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1101 AM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 953 AM EDT MON MAY 20 2013
A STORM SYSTEM ORGANIZING OVER THE PLAINS WILL SLOWLY MOVE ACROSS
THE GREAT LAKES REGION THROUGH MID-WEEK. THIS SYSTEM WILL GENERATE
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS ACROSS NORTHERN
MICHIGAN THROUGH WEDNESDAY NIGHT. DRY AND SEASONABLY COOL CONDITIONS
ARE EXPECTED FOR THE UPCOMING HOLIDAY WEEKEND.
&&
.UPDATE...
ISSUED AT 1100 AM EDT MON MAY 20 2013
HAVE MADE SOME CHANGES TO THE GOING FORECAST THIS AFTERNOON. FIRST
OFF...WARM FRONT CURRENTLY BISECTS NRN LOWER MICHIGAN WITH EASTERLY
FLOW FROM M-32 NORTHWARD. NORTH OF THE FRONT...MARINE STRATUS OFF
LAKE HURON HAS EXPANDED INTO NORTHEAST LOWER MICHIGAN/TIP OF THE
MITT AREA AND INTO THE STRAITS AND EASTERN UPPER MICHIGAN THIS
MORNING. FRONT NOT EXPECTED TO MOVE MUCH TODAY AND FEAR THAT
STRATUS WILL BE AN ISSUE FOR THE NRN PART OF THE CWA THROUGH THE
AFTERNOON AND PERHAPS EVEN THROUGH TONIGHT. HAVE TWEAKED FORECAST
TEMPS WAY DOWN FOR AREAS SUCH AS APN/PLN...ETC. HAVE ALSO TWEAKED
SKY COVER AND TAF FORECASTS TO MAINLY CLOUDY SKIES NORTH OF M-32.
WEATHER WISE...ONE BATCH OF SHOWERS AND A FEW STORMS PUSHING
NORTHEASTWARD OUT OF EASTERN UPPER MICHIGAN CURRENTLY. A FEW THIN
BANDS OF SHOWERS AND STORMS HAVE ALSO DEVELOPED IN THE LAST FEW
HOURS APPARENTLY ALONG EXISTING GRAVITY WAVES INTERACTING WITH
PLUME OF STEEP MID LEVEL LAPSE RATES CURRENTLY OVER THE REGION.
THESE SHOWERS/FEW STORMS WILL MOVE ON THROUGH THE ARE THROUGH THE
REST OF THE MORNING BEFORE STEEP LAPSE RATE PLUME PUSHES EAST OF
THE REGION.
FOR THE AFTERNOON INTO THE EVENING...OBVIOUSLY THE FRONT LOCATION
WILL BE A BIG PLAYER FOR TSTM DEVELOPMENT AND I DONT EXPECT IT TO
MOVE MUCH FROM ITS CURRENT LOCATION (DAYTIME HEATING MAY HELP TO
NUDGE IT NORTHWARD JUST A BIT...BUT TIP OF THE MITT MAY BE STUCK
INTO THE MUD ALL DAY). SOUTH FO THE FRONT...MODIFIED 12Z APX
SOUNDING WITH AFTERNOON TEMPS IN THE LOWER 80S AND SFC DEWPOINTS
IN THE LOWER 60S YIELDS AROUND 1500 J/KG MLCAPE VALUES ASSUMING WE
CAN MAINTAIN THOSE DEWPOINTS (ALREADY SEEING SOME CU DEVELOPMENT
DOWN AROUND CADILLAC). BUT WE ALSO HAVE A SUBTLE CAPPING LAYER
AROUND 750 MB AND IT/S UNCLEAR WHAT WILL HAPPEN IN THAT LAYER THIS
AFTERNOON. KICKER MAY BE THE MID LEVEL IMPULSE AND CORRIDOR OF
STRONGER WINDS ALOFT NOTED UPSTREAM OVER IOWA AND WILL PUSH UP
INTO EASTERN WISCONSIN/FAR WESTERN PART OF THE CWA LATER THIS
AFTERNOON...BRINGING SOME MODEST SYNOPTIC FORCING AS WELL AS
BETTER 0-6KM BULK SHEAR VALUES OF 30 TO 40 KNOTS FOR STORM
ORGANIZATION.
SO AT THIS POINT...THINK THUNDERSTORM DEVELOPMENT IS LIKELY LATER
THIS AFTERNOON EITHER UPSTREAM AND MOVING INTO THE REGION FROM THE
SW OR DEVELOPING OVER THE SRN TIER OF COUNTIES OF THIS CWA...OR
BOTH. ANY STORMS THAT DEVELOP WILL BE CAPABLE OF STRONG WINDS AND
HAIL. HAVE TO WATCH JUST WHERE THIS FRONT ENDS UP WITH RESULTING
BACKED FLOW AND ROTATING STORM POTENTIAL AS WELL.
UPDATE ISSUED AT 650 AM EDT MON MAY 20 2013
RESIDUAL AREA SHOWER AND STORMS HAS REACHED NRN LAKE MICHIGAN
EARLY THIS MORNING...AND AS GREATLY DIMINISHED IN BOTH INTENSITY
AND AREAL COVERAGE AS IT MOVES INTO THE MORE STABLE AND DRIER
AIRMASS OVER OUR CWA. THIS ARE OF CONVECTION WILL CLIP OUR
COUNTIES IN ERN UPR MICHIGAN BEFORE EXITING N/NE INTO ONTARIO...
CONTINUING TO DIMINISH AS IT DOES SO. CERTAINLY EXPECT PRECIP
CHANCES WILL INCREASE FROM WEST TO EAST THROUGHOUT THE DAY. HAVE
MADE SOME MINOR TIMING ADJUSTMENTS TO WX/POPS THIS MORNING BASED
ON RADAR TRENDS. SEVERAL LOCATIONS ARE STILL IN THE LOWER 60S THIS
MORNING...AND WE SHOULD HAVE NO PROBLEM REACHING WELL INTO THE 70S
AND LOWER 80S ACROSS NRN LWR MICHIGAN SOUTH OF THE STATIONARY
FRONT IN WAA PATTERN.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 323 AM EDT MON MAY 20 2013
CURRENTLY, SFC AND 500 MB LOWS IN THE PLAINS ARE BEGINNING TO STACK
UP WITH THE WARM FRONT EXTENDING ACROSS NORTHERN LOWER THIS MORNING,
THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS DROPS SOUTH INTO THE
SOUTHERN PLAINS AND INTO WEST TEXAS. ON THE KAPX RADAR, A FEW LIGHT
SHOWERS IN AND AROUND EASTERN UPPER, OTHERWISE, THE STORMS IN
WISCONSIN, ARE HEADING NNE AND AREN`T MAKING MUCH IN EASTWARD
PROGRESSION.
TODAY...WHILE THE GFS CONTINUES IT`S PRECIP BULL`S EYES OVER THE
FORECAST AREA, THE ECMWF CONTINUES TO SHOW A PATTERN OF ISOLATED
SHOWERS FOR THE MORNING WHILE LEAVING THE MAIN BULK OF THE THUNDER
IN WISCONSIN AND W UPPER. THE WARM FRONT OVER THE NEXT COUPLE OF
HOURS WILL MOVE NORTH THROUGH THE STRAITS LEAVING A CAPPED MOIST
LOWER LEVEL RIPE FOR THE AFTERNOON. THE MAIN PROBLEM WITH THE GFS
IDEA IS THE OVERLY AGGRESSIVE DEWPOINTS, WHICH IT HAS ALREADY IN THE
LOWER 60S. WHILE THE ECMWF HAS THE SFC DEWPOINTS IN THE UPPER 50S.
BASED ON THE TRAJECTORIES, NOT EXPECTING THE LOWER TO MID 60S
DEWPOINTS HERE UNTIL CLOSER TO 15Z. BY THE AFTERNOON, BOTH THE
MODELS HAVE THE 500 MB JET STREAK MOVING INTO NORTHERN LAKE
MICHIGAN. THIS INCREASES THE 0-6KM BULK SHEAR TO AROUND 40KTS. THE
ECMWF SHOWS A 500 M ML CAPE OF AROUND 1000 J/KG AT 18Z WHILE THE GFS
IS TWICE THIS, PROBABLY DUE TO THE SFC MOISTURE PROBLEMS NOTED BY
NCEP.
TONIGHT...THE MODELS CONTINUE THE HIGH 500 M ML CAPE VALUES INTO THE
EARLY EVENING. AS THE SFC HEATING SUBSIDES, THE EXPECTATION WILL BE
THAT THE SEVERE THREAT WILL DIMINISH. HOWEVER, WHILE THE INSTABILITY
WANES, THE MOISTURE WILL REMAIN HIGH WITH THE 500 MB JET STREAK OVER
THE REGION. THIS COULD CAUSE PROBLEMS WITH HEAVY RAIN AT TIMES.
WHILE I DON`T TRUST THE SFC MOISTURE IN THE GFS, EVEN IF YOU SCALE
BACK THE PWAT THERE IS STILL ABOUT 1" OR SO OF MOISTURE THERE. SO
CONTINUE THE LIKELY SHOWERS AND THUNDERSTORMS. ALTHOUGH THE THUNDER
SHOULD BECOME LESS AND LESS GOING INTO THE OVERNIGHT PERIOD.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM EDT MON MAY 20 2013
TUESDAY THRU WEDNESDAY...VERTICALLY STACKED LOW PRESSURE OVER THE
NRN PLAINS AND UPPER MISSISSIPPI VALLEY WILL BEGIN TO TAP INTO GULF
MOISTURE IN ERNEST ON TUESDAY...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. THIS
DEEPER MOISTURE WILL INTERACT WITH THE STATIONARY FRONT AND A SERIES
OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING UPPER
LOWER...LENDING TO CONTINUED DEVELOPMENT OF NUMEROUS SHOWERS AND
THUNDERSTORMS THRU WEDNESDAY. BROAD 850 MB THETA E RIDGING WILL HOLD
OVER MAINLY LWR MICHIGAN TUESDAY THRU WEDNESDAY...BUT LOW LEVEL JET
SOUTH OF MICHIGAN WILL LIKELY FOCUS STRONGER CONVECTION TO OUR
SOUTH. CERTAINLY CANNOT RULE OUT THE POSSIBILITY OF A FEW ISOLD
STRONGER/SVR STORMS THRU THIS PERIOD GIVEN DEEP MOISTURE AND GOOD
DYNAMICS. WILL MAINTAIN LIKELY POPS FOR OUR ENTIRE CWA TUESDAY THRU
WEDNESDAY NIGHT...WITH THUNDER CHANCES ENDING BY WEDNESDAY NIGHT AS
THE SURFACE LOW TRACKS RIGHT OVER OUR CWA. AFTER A RATHER WARM START
TO THE WORK WEEK...HIGH TEMPS WILL RANGE FROM AROUND 60 DEGREES IN
ERN UPR MICHIGAN NORTH OF THE FRONT TO THE UPPER 60S TO MID 70S IN
THE VCNTY OF THE FRONT IN NRN LWR MICHIGAN. LOW TEMPS TUESDAY NIGHT
WILL RANGE FROM THE UPPER 40S IN ERN UPR MICHIGAN TO AROUND 60 ALONG
OUR SRN COUNTIES. LOW TEMPS WEDNESDAY NIGHT WILL BE IN THE MID 40S
TO LOWER 50S.
AS WE HEAD INTO MEMORIAL DAY WEEKEND...THURSDAY THRU SUNDAY...
SLOWLY MORNING SURFACE AND UPPER LOW CENTERS WILL EXIT EAST TOWARD
NEW ENGLAND THURSDAY. SOME SHOWERS WILL LINGER ACROSS OUR CWA ON
THURSDAY...BUT SHOULD COME TO AN END BY THURSDAY NIGHT AS COLDER AND
DRIER AIR FILTER INTO THE REGION BEHIND THE DEPARTING LOW. COOL
CANADIAN HIGH PRESSURE WILL SETTLE INTO MICHIGAN FOR MEMORIAL
WEEKEND. CORE OF THE COLD AIR WILL REMAIN NE OF MICHIGAN...BUT
LIMITED CAA WILL DROP HIGH TEMPS INTO THE MID 50S TO TO LOWER 60S
FOR BOTH THURSDAY AND FRIDAY. THE WEEKEND STILL LOOKS DRY WITH
COOLER THAN NORMAL TEMPS AS THE SURFACE HIGH AND BROAD UPPER LEVEL
TROUGHING BOTH REMAIN LOCKED OVER THE GREAT LAKES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 650 AM EDT MON MAY 20 2013
MAINLY VFR CONDITIONS ARE EXPECTED THRU TUESDAY MORNING DESPITE
INCREASING CHANCES OF SHOWERS AND STORMS ALONG A STATIONARY FRONT
OVER NRN LWR MICHIGAN. VSBYS AND CIGS MAY TEMPORARILY DROP TO MVFR
WITHIN HEAVIER SHOWERS/STORMS. WINDS WILL REMAIN OUT OF THE SE AT
AROUND 10 KTS.
&&
.MARINE...
ISSUED AT 323 AM EDT MON MAY 20 2013
IF THE WARM FRONT GETS NORTH OF THE FORECAST AREA, THEN THE ECMWF
IDEA OF THE SLACK GRADIENT THROUGH TODAY AND TONIGHT WILL BE RIGHT.
WHICH WILL KEEP THE WINDS BELOW SMALL CRAFT, AN IDEA THAT THE GFS
ALLOWS OVERNIGHT. HOWEVER, BY TUESDAY, THE GRADIENT WILL TIGHTEN AS
THE SFC LOW APPROACHES THE REGION. THIS COULD, WITH SOME COASTAL
CONVERGENCE, ALLOW THE WINDS TO GUST TO OVER SMALL CRAFT ADVISORY
CRITERIA FOR THE DAY, BUT AS THE SFC LOW DRAWS CLOSER, THE WINDS
WILL DIMINISH WITH THE SLACKENING GRADIENT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...BA
SYNOPSIS...MSB
SHORT TERM...JL
LONG TERM...MR
AVIATION...MR
MARINE...JL
000
FXUS63 KAPX 201050
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
650 AM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 323 AM EDT MON MAY 20 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.UPDATE...
ISSUED AT 650 AM EDT MON MAY 20 2013
RESIDUAL AREA SHOWER AND STORMS HAS REACHED NRN LAKE MICHIGAN
EARLY THIS MORNING...AND AS GREATLY DIMINISHED IN BOTH INTENSITY
AND AREAL COVERAGE AS IT MOVES INTO THE MORE STABLE AND DRIER
AIRMASS OVER OUR CWA. THIS ARE OF CONVECTION WILL CLIP OUR
COUNTIES IN ERN UPR MICHIGAN BEFORE EXITING N/NE INTO ONTARIO...
CONTINUING TO DIMINISH AS IT DOES SO. CERTAINLY EXPECT PRECIP
CHANCES WILL INCREASE FROM WEST TO EAST THROUGHOUT THE DAY. HAVE
MADE SOME MINOR TIMING ADJUSTMENTS TO WX/POPS THIS MORNING BASED
ON RADAR TRENDS. SEVERAL LOCATIONS ARE STILL IN THE LOWER 60S THIS
MORNING...AND WE SHOULD HAVE NO PROBLEM REACHING WELL INTO THE 70S
AND LOWER 80S ACROSS NRN LWR MICHIGAN SOUTH OF THE STATIONARY
FRONT IN WAA PATTERN.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 323 AM EDT MON MAY 20 2013
CURRENTLY, SFC AND 500 MB LOWS IN THE PLAINS ARE BEGINNING TO STACK
UP WITH THE WARM FRONT EXTENDING ACROSS NORTHERN LOWER THIS MORNING,
THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS DROPS SOUTH INTO THE
SOUTHERN PLAINS AND INTO WEST TEXAS. ON THE KAPX RADAR, A FEW LIGHT
SHOWERS IN AND AROUND EASTERN UPPER, OTHERWISE, THE STORMS IN
WISCONSIN, ARE HEADING NNE AND AREN`T MAKING MUCH IN EASTWARD
PROGRESSION.
TODAY...WHILE THE GFS CONTINUES IT`S PRECIP BULL`S EYES OVER THE
FORECAST AREA, THE ECMWF CONTINUES TO SHOW A PATTERN OF ISOLATED
SHOWERS FOR THE MORNING WHILE LEAVING THE MAIN BULK OF THE THUNDER
IN WISCONSIN AND W UPPER. THE WARM FRONT OVER THE NEXT COUPLE OF
HOURS WILL MOVE NORTH THROUGH THE STRAITS LEAVING A CAPPED MOIST
LOWER LEVEL RIPE FOR THE AFTERNOON. THE MAIN PROBLEM WITH THE GFS
IDEA IS THE OVERLY AGGRESSIVE DEWPOINTS, WHICH IT HAS ALREADY IN THE
LOWER 60S. WHILE THE ECMWF HAS THE SFC DEWPOINTS IN THE UPPER 50S.
BASED ON THE TRAJECTORIES, NOT EXPECTING THE LOWER TO MID 60S
DEWPOINTS HERE UNTIL CLOSER TO 15Z. BY THE AFTERNOON, BOTH THE
MODELS HAVE THE 500 MB JET STREAK MOVING INTO NORTHERN LAKE
MICHIGAN. THIS INCREASES THE 0-6KM BULK SHEAR TO AROUND 40KTS. THE
ECMWF SHOWS A 500 M ML CAPE OF AROUND 1000 J/KG AT 18Z WHILE THE GFS
IS TWICE THIS, PROBABLY DUE TO THE SFC MOISTURE PROBLEMS NOTED BY
NCEP.
TONIGHT...THE MODELS CONTINUE THE HIGH 500 M ML CAPE VALUES INTO THE
EARLY EVENING. AS THE SFC HEATING SUBSIDES, THE EXPECTATION WILL BE
THAT THE SEVERE THREAT WILL DIMINISH. HOWEVER, WHILE THE INSTABILITY
WANES, THE MOISTURE WILL REMAIN HIGH WITH THE 500 MB JET STREAK OVER
THE REGION. THIS COULD CAUSE PROBLEMS WITH HEAVY RAIN AT TIMES.
WHILE I DON`T TRUST THE SFC MOISTURE IN THE GFS, EVEN IF YOU SCALE
BACK THE PWAT THERE IS STILL ABOUT 1" OR SO OF MOISTURE THERE. SO
CONTINUE THE LIKELY SHOWERS AND THUNDERSTORMS. ALTHOUGH THE THUNDER
SHOULD BECOME LESS AND LESS GOING INTO THE OVERNIGHT PERIOD.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM EDT MON MAY 20 2013
TUESDAY THRU WEDNESDAY...VERTICALLY STACKED LOW PRESSURE OVER THE
NRN PLAINS AND UPPER MISSISSIPPI VALLEY WILL BEGIN TO TAP INTO GULF
MOISTURE IN ERNEST ON TUESDAY...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. THIS
DEEPER MOISTURE WILL INTERACT WITH THE STATIONARY FRONT AND A SERIES
OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING UPPER
LOWER...LENDING TO CONTINUED DEVELOPMENT OF NUMEROUS SHOWERS AND
THUNDERSTORMS THRU WEDNESDAY. BROAD 850 MB THETA E RIDGING WILL HOLD
OVER MAINLY LWR MICHIGAN TUESDAY THRU WEDNESDAY...BUT LOW LEVEL JET
SOUTH OF MICHIGAN WILL LIKELY FOCUS STRONGER CONVECTION TO OUR
SOUTH. CERTAINLY CANNOT RULE OUT THE POSSIBILITY OF A FEW ISOLD
STRONGER/SVR STORMS THRU THIS PERIOD GIVEN DEEP MOISTURE AND GOOD
DYNAMICS. WILL MAINTAIN LIKELY POPS FOR OUR ENTIRE CWA TUESDAY THRU
WEDNESDAY NIGHT...WITH THUNDER CHANCES ENDING BY WEDNESDAY NIGHT AS
THE SURFACE LOW TRACKS RIGHT OVER OUR CWA. AFTER A RATHER WARM START
TO THE WORK WEEK...HIGH TEMPS WILL RANGE FROM AROUND 60 DEGREES IN
ERN UPR MICHIGAN NORTH OF THE FRONT TO THE UPPER 60S TO MID 70S IN
THE VCNTY OF THE FRONT IN NRN LWR MICHIGAN. LOW TEMPS TUESDAY NIGHT
WILL RANGE FROM THE UPPER 40S IN ERN UPR MICHIGAN TO AROUND 60 ALONG
OUR SRN COUNTIES. LOW TEMPS WEDNESDAY NIGHT WILL BE IN THE MID 40S
TO LOWER 50S.
AS WE HEAD INTO MEMORIAL DAY WEEKEND...THURSDAY THRU SUNDAY...
SLOWLY MORNING SURFACE AND UPPER LOW CENTERS WILL EXIT EAST TOWARD
NEW ENGLAND THURSDAY. SOME SHOWERS WILL LINGER ACROSS OUR CWA ON
THURSDAY...BUT SHOULD COME TO AN END BY THURSDAY NIGHT AS COLDER AND
DRIER AIR FILTER INTO THE REGION BEHIND THE DEPARTING LOW. COOL
CANADIAN HIGH PRESSURE WILL SETTLE INTO MICHIGAN FOR MEMORIAL
WEEKEND. CORE OF THE COLD AIR WILL REMAIN NE OF MICHIGAN...BUT
LIMITED CAA WILL DROP HIGH TEMPS INTO THE MID 50S TO TO LOWER 60S
FOR BOTH THURSDAY AND FRIDAY. THE WEEKEND STILL LOOKS DRY WITH
COOLER THAN NORMAL TEMPS AS THE SURFACE HIGH AND BROAD UPPER LEVEL
TROUGHING BOTH REMAIN LOCKED OVER THE GREAT LAKES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 650 AM EDT MON MAY 20 2013
MAINLY VFR CONDITIONS ARE EXPECTED THRU TUESDAY MORNING DESPITE
INCREASING CHANCES OF SHOWERS AND STORMS ALONG A STATIONARY FRONT
OVER NRN LWR MICHIGAN. VSBYS AND CIGS MAY TEMPORARILY DROP TO MVFR
WITHIN HEAVIER SHOWERS/STORMS. WINDS WILL REMAIN OUT OF THE SE AT
AROUND 10 KTS.
&&
.MARINE...
ISSUED AT 323 AM EDT MON MAY 20 2013
IF THE WARM FRONT GETS NORTH OF THE FORECAST AREA, THEN THE ECMWF
IDEA OF THE SLACK GRADIENT THROUGH TODAY AND TONIGHT WILL BE RIGHT.
WHICH WILL KEEP THE WINDS BELOW SMALL CRAFT, AN IDEA THAT THE GFS
ALLOWS OVERNIGHT. HOWEVER, BY TUESDAY, THE GRADIENT WILL TIGHTEN AS
THE SFC LOW APPROACHES THE REGION. THIS COULD, WITH SOME COASTAL
CONVERGENCE, ALLOW THE WINDS TO GUST TO OVER SMALL CRAFT ADVISORY
CRITERIA FOR THE DAY, BUT AS THE SFC LOW DRAWS CLOSER, THE WINDS
WILL DIMINISH WITH THE SLACKENING GRADIENT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...MR
SYNOPSIS...MR
SHORT TERM...JL
LONG TERM...MR
AVIATION...MR
MARINE...JL
000
FXUS63 KAPX 200743
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
343 AM EDT MON MAY 20 2013
.SYNOPSIS...
ISSUED AT 323 AM EDT MON MAY 20 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 323 AM EDT MON MAY 20 2013
CURRENTLY, SFC AND 500 MB LOWS IN THE PLAINS ARE BEGINNING TO STACK
UP WITH THE WARM FRONT EXTENDING ACROSS NORTHERN LOWER THIS MORNING,
THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS DROPS SOUTH INTO THE
SOUTHERN PLAINS AND INTO WEST TEXAS. ON THE KAPX RADAR, A FEW LIGHT
SHOWERS IN AND AROUND EASTERN UPPER, OTHERWISE, THE STORMS IN
WISCONSIN, ARE HEADING NNE AND AREN`T MAKING MUCH IN EASTWARD
PROGRESSION.
TODAY...WHILE THE GFS CONTINUES IT`S PRECIP BULL`S EYES OVER THE
FORECAST AREA, THE ECMWF CONTINUES TO SHOW A PATTERN OF ISOLATED
SHOWERS FOR THE MORNING WHILE LEAVING THE MAIN BULK OF THE THUNDER
IN WISCONSIN AND W UPPER. THE WARM FRONT OVER THE NEXT COUPLE OF
HOURS WILL MOVE NORTH THROUGH THE STRAITS LEAVING A CAPPED MOIST
LOWER LEVEL RIPE FOR THE AFTERNOON. THE MAIN PROBLEM WITH THE GFS
IDEA IS THE OVERLY AGGRESSIVE DEWPOINTS, WHICH IT HAS ALREADY IN THE
LOWER 60S. WHILE THE ECMWF HAS THE SFC DEWPOINTS IN THE UPPER 50S.
BASED ON THE TRAJECTORIES, NOT EXPECTING THE LOWER TO MID 60S
DEWPOINTS HERE UNTIL CLOSER TO 15Z. BY THE AFTERNOON, BOTH THE
MODELS HAVE THE 500 MB JET STREAK MOVING INTO NORTHERN LAKE
MICHIGAN. THIS INCREASES THE 0-6KM BULK SHEAR TO AROUND 40KTS. THE
ECMWF SHOWS A 500 M ML CAPE OF AROUND 1000 J/KG AT 18Z WHILE THE GFS
IS TWICE THIS, PROBABLY DUE TO THE SFC MOISTURE PROBLEMS NOTED BY
NCEP.
TONIGHT...THE MODELS CONTINUE THE HIGH 500 M ML CAPE VALUES INTO THE
EARLY EVENING. AS THE SFC HEATING SUBSIDES, THE EXPECTATION WILL BE
THAT THE SEVERE THREAT WILL DIMINISH. HOWEVER, WHILE THE INSTABILITY
WANES, THE MOISTURE WILL REMAIN HIGH WITH THE 500 MB JET STREAK OVER
THE REGION. THIS COULD CAUSE PROBLEMS WITH HEAVY RAIN AT TIMES.
WHILE I DON`T TRUST THE SFC MOISTURE IN THE GFS, EVEN IF YOU SCALE
BACK THE PWAT THERE IS STILL ABOUT 1" OR SO OF MOISTURE THERE. SO
CONTINUE THE LIKELY SHOWERS AND THUNDERSTORMS. ALTHOUGH THE THUNDER
SHOULD BECOME LESS AND LESS GOING INTO THE OVERNIGHT PERIOD.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM EDT MON MAY 20 2013
TUESDAY THRU WEDNESDAY...VERTICALLY STACKED LOW PRESSURE OVER THE
NRN PLAINS AND UPPER MISSISSIPPI VALLEY WILL BEGIN TO TAP INTO GULF
MOISTURE IN ERNEST ON TUESDAY...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. THIS
DEEPER MOISTURE WILL INTERACT WITH THE STATIONARY FRONT AND A SERIES
OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING UPPER
LOWER...LENDING TO CONTINUED DEVELOPMENT OF NUMEROUS SHOWERS AND
THUNDERSTORMS THRU WEDNESDAY. BROAD 850 MB THETA E RIDGING WILL HOLD
OVER MAINLY LWR MICHIGAN TUESDAY THRU WEDNESDAY...BUT LOW LEVEL JET
SOUTH OF MICHIGAN WILL LIKELY FOCUS STRONGER CONVECTION TO OUR
SOUTH. CERTAINLY CANNOT RULE OUT THE POSSIBILITY OF A FEW ISOLD
STRONGER/SVR STORMS THRU THIS PERIOD GIVEN DEEP MOISTURE AND GOOD
DYNAMICS. WILL MAINTAIN LIKELY POPS FOR OUR ENTIRE CWA TUESDAY THRU
WEDNESDAY NIGHT...WITH THUNDER CHANCES ENDING BY WEDNESDAY NIGHT AS
THE SURFACE LOW TRACKS RIGHT OVER OUR CWA. AFTER A RATHER WARM START
TO THE WORK WEEK...HIGH TEMPS WILL RANGE FROM AROUND 60 DEGREES IN
ERN UPR MICHIGAN NORTH OF THE FRONT TO THE UPPER 60S TO MID 70S IN
THE VCNTY OF THE FRONT IN NRN LWR MICHIGAN. LOW TEMPS TUESDAY NIGHT
WILL RANGE FROM THE UPPER 40S IN ERN UPR MICHIGAN TO AROUND 60 ALONG
OUR SRN COUNTIES. LOW TEMPS WEDNESDAY NIGHT WILL BE IN THE MID 40S
TO LOWER 50S.
AS WE HEAD INTO MEMORIAL DAY WEEKEND...THURSDAY THRU SUNDAY...
SLOWLY MORNING SURFACE AND UPPER LOW CENTERS WILL EXIT EAST TOWARD
NEW ENGLAND THURSDAY. SOME SHOWERS WILL LINGER ACROSS OUR CWA ON
THURSDAY...BUT SHOULD COME TO AN END BY THURSDAY NIGHT AS COLDER AND
DRIER AIR FILTER INTO THE REGION BEHIND THE DEPARTING LOW. COOL
CANADIAN HIGH PRESSURE WILL SETTLE INTO MICHIGAN FOR MEMORIAL
WEEKEND. CORE OF THE COLD AIR WILL REMAIN NE OF MICHIGAN...BUT
LIMITED CAA WILL DROP HIGH TEMPS INTO THE MID 50S TO TO LOWER 60S
FOR BOTH THURSDAY AND FRIDAY. THE WEEKEND STILL LOOKS DRY WITH
COOLER THAN NORMAL TEMPS AS THE SURFACE HIGH AND BROAD UPPER LEVEL
TROUGHING BOTH REMAIN LOCKED OVER THE GREAT LAKES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1153 PM EDT SUN MAY 19 2013
MOSTLY VFR...THOUGH THE CHANCE FOR RESTRICTIONS DUE TO SHRA/TSRA
WILL INCREASE THRU THE FORECAST. ALSO SOME PATCHY MVFR VSBYS IN
FOG/HAZE OVERNIGHT.
IN ADVANCE OF A COMPLEX LOW PRESSURE SYSTEM IN THE PLAINS...WARMER
AND MORE HUMID AIR CONTINUES TO GRADUALLY WORK NORTHWARD INTO MI.
THE CHANCE FOR THIS AIRMASS TO PRODUCE SHRA/TSRA WILL
INCREASE...ESPECIALLY ON MONDAY AFTERNOON. HAVE CONTINUED TO
CARRY VCTS AT ALL TAF SITES FOR A SEVERAL HOURS IN THE
AFTERNOON/EARLY EVENING. THAT IS CERTAINLY NOT THE ONLY TIME
DURING WHICH SHRA/TSRA COULD OCCUR...BUT DO NOT WANT TO BE
CARRYING TSRA FOR MANY MANY HOURS...SO TRIED TO IDENTIFY THE MOST
LIKELY PERIOD.
SOME POTENTIAL FOR VSBY RESTRICTIONS IN BR OVERNIGHT...AND ALL
TAFS BUT PLN HAVE TEMPO GROUPS FOR MVFR VSBYS.
LIGHT WINDS TONIGHT...BECOMING SOMEWHAT BREEZY FROM THE EAST AT
APN/PLN MONDAY...LESS BLUSTERY FROM THE SOUTH TVC/MBL.
&&
.MARINE...
ISSUED AT 323 AM EDT MON MAY 20 2013
IF THE WARM FRONT GETS NORTH OF THE FORECAST AREA, THEN THE ECMWF
IDEA OF THE SLACK GRADIENT THROUGH TODAY AND TONIGHT WILL BE RIGHT.
WHICH WILL KEEP THE WINDS BELOW SMALL CRAFT, AN IDEA THAT THE GFS
ALLOWS OVERNIGHT. HOWEVER, BY TUESDAY, THE GRADIENT WILL TIGHTEN AS
THE SFC LOW APPROACHES THE REGION. THIS COULD, WITH SOME COASTAL
CONVERGENCE, ALLOW THE WINDS TO GUST TO OVER SMALL CRAFT ADVISORY
CRITERIA FOR THE DAY, BUT AS THE SFC LOW DRAWS CLOSER, THE WINDS
WILL DIMINISH WITH THE SLACKENING GRADIENT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...MR
SHORT TERM...JL
LONG TERM...MR
AVIATION...JZ
MARINE...JL
000
FXUS63 KAPX 200353
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1153 PM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.UPDATE...
ISSUED AT 945 PM EDT SUN MAY 19 2013
A FEW MID-LEVEL RETURNS ARE GETTING GOING IN PARTS OF LUCE/
CHIPPEWA COUNTIES...WITH SOMEWHAT MORE VIGOROUS SHRA OUT OVER THE
BIG LAKE. IN NORTHERN LOWER...HIGH-BASED CU ARE FOUND IN FAR
NORTHERN AND NE SECTIONS. 00Z APX SOUNDING SHOWS ONLY A NARROW
MOIST LAYER UP AT 775MB...ONE THAT LEAVES SOME 70-80J/KG OF CIN TO
OVERCOME. SATURATION IN LOWER LEVELS (LIKE THE NAM SHOWS AT
800-850MB) WOULD GIVE US A MUCH BETTER CHANCE OF GETTING PAST THE
CAP AT 700MB. AS IS...GETTING CONVECTION GOING IN NORTHERN LOWER
IN THE VERY SHORT TERM LOOKS TO BE DIFFICULT.
SO...THE GOING FORECAST IS IN REASONABLY SOUND SHAPE...WITH CHANCE
POPS BEGINNING ABOUT NOW IN PARTS OF EASTERN UPPER...AND EXPANDING
SE-WARD INTO NW AND N CENTRAL LOWER LATE. TEMPS WILL BE
MILD...WITH ONLY SMALL ADJUSTMENTS NEEDED.
UPDATE ISSUED AT 742 PM EDT SUN MAY 19 2013
RECENTLY DEVELOPED CU FIELD HAS DECIDED TO BE RATHER
TRANSIENT...RACING OFF INTO N CENTRAL LOWER MI. THERE ARE SOME CU
LINES LEFT BEHIND IN NW LOWER. THERE IS PERHAPS A VERY SLIGHT
CHANCE FOR THESE TO DEVELOP INTO CONVECTION BETWEEN 00Z AND 03Z IF
THE CAP WEAKENS AS MUCH AS PROGGED BY THE NAM (SEE EARLIER
UPDATE). WILL CONTINUE TO CHASE CLOUD TRENDS...OTHERWISE NO
CHANGES.
UPDATE ISSUED AT 635 PM EDT SUN MAY 19 2013
SOME INTERESTING TRENDS OVER THE LAST HOUR OR SO. 1ST...CU FIELD
OVER THE INTERIOR OF NORTHERN LOWER MI CONTINUES TO DIMINISH...NOW
LARGELY CONFINED TO MIO AND THE SURROUNDING AREA. RAPIDLY RUNNING
OUT OF TIME TO SEE ANYTHING FIRE THERE.
2ND...A HIGH-BASED CU FIELD HAS RAPIDLY DEVELOPED ALONG THE LAKE
MI COAST WEST OF TVC OVER THE PAST HOUR. OBVIOUSLY NOT DIRECTLY
ASSOCIATED WITH DIURNAL HEATING...GIVEN THE LOCATION OVER THE
MARINE LAYER. A FEW SHORT-TERM MODEL SOUNDINGS (LED OF COURSE BY
THE NAM) ARE SHOWING ENOUGH MOISTURE ADVECTION INTO THE 850-800MB
LAYER TO PRODUCE SATURATION. THE NAM ALSO LEADS THE WAY IN THE
RESULTING ELEVATED INSTABILITY...WITH MUCAPES NEARING 1K J/KG BY
03Z...AND A WEAKENING OF THE CAP (10C 750MB TEMPS OFF THE NAM...12C
FROM THE RUC/LOCAL WRF). THOUGH THE NAM IS MOIST TO A FAULT...IT
DOES AT LEAST REFLECT THE CLOUD DEVELOPMENT THAT WE ARE SEEING IN
THE AREA. AND IT WOULD SUGGEST THAT ANY SORT OF WEAK IMPULSE
(SAY...EXPELLED BY THE DYING CLUSTER OF CONVECTION NEAR LK
WINNEBAGO) MIGHT KICK SOMETHING OFF.
AM INCREASING CLOUD COVER...BUT /FOR NOW/ WILL NOT INTRODUCE POPS
ANY EARLIER THAN IS ALREADY IN THE FORECAST (06Z/2AM).
HOWEVER...WILL TAKE A VERY CLOSE LOOK AT 00Z GRB/APX SOUNDINGS AND
OTHER DATA THAT IS SOON TO ARRIVE...IN PARTICULAR LOOKING AT HOW
THE CAP MIGHT BEHAVE THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
POSSIBLY AN ISOLATED EARLY EVENING SHOWER OVER INTERIOR AREAS MAINLY
INVOF LAKE BREEZE BOUNDARIES. THESE SHOULD DISSIPATE EARLY WITH LOSS
OF DAYTIME HEATING. AN ELEVATED WARM FRONT LIFTS THROUGH THE REGION
LATE TONIGHT /AFTER 06Z/...WITH SURFACE FRONTAL BOUNDARY DRAPED
ACROSS THE AREA. UNIMPRESSIVE KINEMATICS...WITH BEST FORCING
REMAINING WEST OF THE AREA CLOSER TO UPPER TROUGH. 850M THETA-E
RIDGE FOLDS OVER INTO THE AREA LATE TONIGHT WITH STEEPER MID LEVEL
LAPSE RATES AND MUCAPES OVER 500 J/KG. THIS ALL POINTS TO AT LEAST
A CHANCE OF THUNDER OVER NRN/WRN AREAS. FAIRLY MILD...WITH LOWS
IN THE 50S NORTH TO 60S SOUTH. WILL ALSO ADD FOG FOR LATER TONIGHT TO
NEARSHORE WATERS AND PORTIONS OF NORTHERN LOWER MICHIGAN...AS LOW
LEVEL MOISTURE CONTINUES TO INCREASE AND POOL INVOF BOUNDARY.
MONDAY...CHALLENGING FORECAST GIVEN QUESTIONABLE EVOLUTION OF
UPSTREAM CONVECTION. PRECIP CHANCES WILL CONTINUE TO INCREASE FROM
WEST TO EAST WITH FRONTAL BOUNDARY DRAPED ACROSS NRN LOWER
MICHIGAN. DEEPENING TROUGH/LOW PRESSURE IN THE PLAINS WILL BEGIN TO
TAP INTO GULF MOISTURE...ADVECTING DEEPER MOISTURE NORTHWARD THRU
THE LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES.
AS THIS DEEPER MOISTURE BEGINS TO INTERACT WITH FRONTAL BOUNDARY AND
A SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE
DEEPENING UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL
INCREASE. DIFFICULT TO PINPOINT EXACT DETAILS GIVEN UNCERTAINTY IN
FRONTAL LOCATION/CONVECTIVE EVOLUTION...BUT BROAD LARGE-SCALE ASCENT
ON THE ERN EDGE OF UPPER TROUGH AND AIRMASS DESTABILIZATION SHOULD
RESULT IN A GOOD CHANCE OF SHOWERS/STORMS FOR THE AFTN HOURS.
BACKWARD TRAJECTORY OF DWPTS SHOW PARCEL ORIGINATION FROM CENTRAL
INDIANA FOR MONDAY AFTN...WHICH BRINGS SFC DWPTS INTO THE LOWER
60S FOR PORTIONS OF THE AREA MONDAY AFTERNOON. MODIFYING FCST
SOUNDINGS FOR A PARCEL TEMP OF 79/62 YIELD SBCAPES OF 1200 J/KG.
WITH STEEPENING MID LEVEL LAPSE RATES ARRIVING OVER SOUTHWEST
AREAS LATE IN THE DAY AND STRONG BOUNDARY LAYER HEATING
/DESTABILIZATION/...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH
THE MAIN THREAT BEING LARGE HAIL. HIGH TEMPERATURES ANOTHER
CHALLENGE GIVEN CLOUD/PCPN UNCERTAINTY AND WILL BASICALLY TAKE A
MODEL BLEND...WHICH GIVES HIGHS IN THE UPPER 60S OVER ERN UPPER TO
THE LOWER 80S SOUTH. WITH ENOUGH SUNSHINE...TEMPS ALOFT CERTAINLY
WARM ENOUGH TO SUPPORT HIGH TEMPS IN THE MID 80S SOUTH OF M-72.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
INCREASINGLY AMPLIFIED AND SLOW MOVING PATTERN LOOKS TO LOCK IN A
RATHER WET PERIOD OF WEATHER RIGHT THROUGH MID-WEEK. IMPETUS BEHIND
THE RAINS WILL BE PERSISTENT MOISTURE RICH LOW AND MID LEVEL
CONVERGENCE ZONE LAYING OUT ACROSS THE AREA...ALL THE WHILE SLOW
MOVING CENTRAL PLAINS LOW SENDS VARIOUS POCKETS OF ENERGY UP ALONG
IT. FROM A CONCEPTUAL STANDPOINT...MOISTURE SUPPLY LOOKS RATHER
IDEAL...WITH WIDE OPEN GULF OF MEXICO MOISTURE FEED SPIKING PWAT
VALUES UP TO AND EXCEEDING AN INCH AND A HALF RIGHT THROUGH
WEDNESDAY. THAT SAID...CONVECTIVE SEASON NOW IN OVERDRIVE TO OUR
SOUTH AND SOUTHWEST...AND WILL NO DOUBT HAVE PLENTY TO SAY ON THE
OVERALL EVOLUTION OF THIS EVENT. EARLY MEMORIAL DAY WEEKEND GUIDANCE
TRENDS CONTINUE TO INDICATE DEVELOPMENT OF RATHER DEEP WEST/EAST
COAST TROUGHS...WITH HIGH PLAINS RIDGING TUCKED UP IN-BETWEEN. THIS
SHOULD...THEORETICALLY...OPEN THE DOOR FOR A SHOT OF RATHER COOL
CANADIAN AIR AND PERHAPS THE POTENTIALLY FOR ANOTHER OVERNIGHT FROST
EVENT...ESPECIALLY FOR FRIDAY NIGHT. ABOVE YIELDS PLENTY TO TALK
ABOUT...WITH MUCH OF THE FOCUS CENTERED ON IMPENDING WET WEATHER AND
SEVERE WEATHER POTENTIAL.
AS MENTIONED...UPCOMING SET-UP LOOKS RATHER FAVORABLE FOR SOME MUCH
NEEDED RAINS...WITH PERSISTENT MOIST SOUTH FLOW ON FRONT SIDE OF
SLOW MOVING CENTRAL PLAIN LOW PRESSURE INTERSECTING LOW/MID LEVEL
BAROCLINIC AXIS. SURFACE WARM FRONT LOOKS TO GRADUALLY MIX SOUTH
MONDAY NIGHT...AIDED BY COLD LAKE WATERS AND PERIODIC BOUTS OF
CONVECTION...BEFORE PERHAPS BEING PROPELLED BACK NORTH TUESDAY INTO
WEDNESDAY WITH APPROACH OF PRIMARY UPSTREAM WAVE. HARD TO TIME
PERIODS OF BETTER SHOWER AND STORM POTENTIAL...ESPECIALLY WITH
UPSTREAM CONVECTIVE TRENDS AND TIMING OF VARIOUS IMPULSES DICTATING
SUCH. DESPITE PERSISTENCE FOR RAINS SEEN IN GUIDANCE...PREFER TO
KEEP JUST LIKELY WORDING IN THE FORECAST (LEARNED UP HERE TO
NEVER...NEVER TRUST CONVECTION). INITIAL SEVERE THREAT SHOULD REMAIN
TO OUR SOUTHWEST MONDAY NIGHT WHERE MORE PRONOUNCED LOW LEVEL
INSTABILITY AXIS AND DEEPER SHEAR ARE BETTER JUXTAPOSED. INCREASING
CONCERN FOR AT LEAST A MINIMAL SEVERE THREAT HEADING INTO TUESDAY
AND WEDNESDAY AS SURFACE WARM FRONT KICKS BACK NORTH...PERHAPS
REACHING AS FAR NORTH AS THE STRAITS BY WEDNESDAY. MUCH TOO EARLY TO
GET TOO SPECIFIC...BUT NORTHWARD SURGING WARM FRONT ITSELF IS
DISCONCERTING...AS IS POTENTIALLY BREAKING INTO THE WARM SECTOR FOR
AT LEAST PARTS OF THE AREA. MUCH...OF COURSE...WILL DEPEND ON
UPSTREAM CONVECTIVE EVOLUTION...BUT WOULD NOT BE AT ALL SURPRISED TO
SEE OUR FIRST SEVERE THUNDERSTORM EVENT OF THE SEASON (AND ENDING
ONE OF THE LATEST STARTS TO SUCH IN OUR RECENT HISTORY). OVERNIGHT
ISSUED SPC SEVERE GRAPHICS CONCUR...BRINGING TUESDAY INTO WEDNESDAY
SLIGHT RISK CATEGORY UP TO ABOUT M-32. DEFINITELY SOMETHING TO
MONITOR IN THE COMING DAYS...BUT WILL DEFER INTRODUCING THIS THREAT
IN THE LATEST RENDITION OF THE HAZARDOUS WEATHER OUTLOOK UNTIL
BETTER CONFIDENCE IS REALIZED. FORECASTING TEMPERATURES EVEN A MUCH
LOWER CONFIDENCE ENDEAVOR THAN ALL THE ABOVE. WILL SIMPLY USE A
CONSENSUS APPROACH FOR NOW...AND WILL HONESTLY STATE FORECAST WILL
LIKELY IN NO WAY MIMIC REALITY.
MID LEVEL LOW OPENS UP AS IT PASSES OVERHEAD LATER WEDNESDAY AND
WEDNESDAY NIGHT (TIMING SUBJECT TO CHANGE...OF COURSE)...EVENTUALLY
BECOMING ABSORBED IN DEEPENING EASTERN TROUGH TO END THE WEEK. RAINS
LOOK TO CONTINUE WEDNESDAY NIGHT...PERHAPS LINGERING INTO THURSDAY.
START OF THE HOLIDAY WEEKEND CONTINUES TO LOOK DRY AND SEASONABLY
COOL AS STRONG CANADIAN HIGH PRESSURE BUILDS SOUTH FRIDAY AND
SATURDAY BETWEEN EASTERN TROUGHING AND HIGH PLAIN RIDGING. HIGHS
TEMPERATURES NOT EXCEPTIONALLY COOL...BUT STILL A FEW DEGREES BELOW
NORMAL...WITH READINGS FRIDAY IN THE UPPER 50S AND LOWER
60S....WARMING SLIGHTLY INTO THE 60S FOR SATURDAY. BIGGER CONCERN
REMAINS FOR SOME RATHER CHILLY OVERNIGHT LOWS. COULD SEE SOME
READINGS DIP INTO THE MIDDLE AND UPPER 30S AS QUICKLY AS THURSDAY
NIGHT...DRIVEN SIMPLY BY SHOT OF CAA ON NORTHEAST TO NORTH WINDS.
PER PATTERN RECOGNITION...FRIDAY NIGHT CONTINUES TO LOOK DOWNRIGHT
CHILLY WITH COOL HIGH PRESSURE AND ATTENDANT DRY AIR CENTERED
DIRECTLY OVERHEAD. DESPITE BEING AT LEAST PARTIALLY CLIMATOLOGICALLY
INFLUENCED AT THIS TIME FRAME...LATEST ECMWF MOS PROGS CONTINUE TO
LOOK RATHER DISCONCERTING...FEATURING WIDESPREAD LOWER AND MIDDLE 30
DEGREE READINGS BY EARLY SATURDAY MORNING (GFS MEX PROGS ALSO
TRENDING COOLER...ALTHOUGH NOT YET TO THIS EXTREME). WILL START THE
PROCESS OF TRENDING COOLER THROUGH THIS PERIOD AND INTRODUCE THE
MENTION OF THIS FROST POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK FOR
NORTHERN LOWER MICHIGAN (FROST/FREEZE SEASON DOESN`T KICK OFF FOR
UPPER MICHIGAN UNTIL MEMORIAL DAY). JUST TOOK A QUICK PERUSAL OF
LATEST 12Z ECMWF...WHICH HAS TRENDED MUCH STRONGER WITH CAA THURSDAY
NIGHT THROUGH SUNDAY. IF THIS IS REALIZED...HIGHS FRIDAY WILL LIKELY
BE STUCK IN THE 50S...WITH OVERNIGHT LOWS RANGING FROM THE MID AND
UPPER 30S THURSDAY NIGHT AND AGAIN SATURDAY NIGHT...WITH WIDESPREAD
UPPER 20 TO MID 30 DEGREE READINGS FRIDAY NIGHT. QUESTIONS ABOUND BY
SUNDAY...WITH SOME POTENTIAL FOR DEVELOPING WAA TO KICK OFF AT LEAST
THE THREAT FOR A FEW SHOWERS. IN NO HURRY TO INTRODUCE THIS JUST YET
GIVEN INHERENT TIMING CONCERNS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1153 PM EDT SUN MAY 19 2013
MOSTLY VFR...THOUGH THE CHANCE FOR RESTRICTIONS DUE TO SHRA/TSRA
WILL INCREASE THRU THE FORECAST. ALSO SOME PATCHY MVFR VSBYS IN
FOG/HAZE OVERNIGHT.
IN ADVANCE OF A COMPLEX LOW PRESSURE SYSTEM IN THE PLAINS...WARMER
AND MORE HUMID AIR CONTINUES TO GRADUALLY WORK NORTHWARD INTO MI.
THE CHANCE FOR THIS AIRMASS TO PRODUCE SHRA/TSRA WILL
INCREASE...ESPECIALLY ON MONDAY AFTERNOON. HAVE CONTINUED TO
CARRY VCTS AT ALL TAF SITES FOR A SEVERAL HOURS IN THE
AFTERNOON/EARLY EVENING. THAT IS CERTAINLY NOT THE ONLY TIME
DURING WHICH SHRA/TSRA COULD OCCUR...BUT DO NOT WANT TO BE
CARRYING TSRA FOR MANY MANY HOURS...SO TRIED TO IDENTIFY THE MOST
LIKELY PERIOD.
SOME POTENTIAL FOR VSBY RESTRICTIONS IN BR OVERNIGHT...AND ALL
TAFS BUT PLN HAVE TEMPO GROUPS FOR MVFR VSBYS.
LIGHT WINDS TONIGHT...BECOMING SOMEWHAT BREEZY FROM THE EAST AT
APN/PLN MONDAY...LESS BLUSTERY FROM THE SOUTH TVC/MBL.
&&
.MARINE...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY THRU TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JZ
MARINE...JK
000
FXUS63 KAPX 200145
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
945 PM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.UPDATE...
ISSUED AT 945 PM EDT SUN MAY 19 2013
A FEW MID-LEVEL RETURNS ARE GETTING GOING IN PARTS OF LUCE/
CHIPPEWA COUNTIES...WITH SOMEWHAT MORE VIGOROUS SHRA OUT OVER THE
BIG LAKE. IN NORTHERN LOWER...HIGH-BASED CU ARE FOUND IN FAR
NORTHERN AND NE SECTIONS. 00Z APX SOUNDING SHOWS ONLY A NARROW
MOIST LAYER UP AT 775MB...ONE THAT LEAVES SOME 70-80J/KG OF CIN TO
OVERCOME. SATURATION IN LOWER LEVELS (LIKE THE NAM SHOWS AT
800-850MB) WOULD GIVE US A MUCH BETTER CHANCE OF GETTING PAST THE
CAP AT 700MB. AS IS...GETTING CONVECTION GOING IN NORTHERN LOWER
IN THE VERY SHORT TERM LOOKS TO BE DIFFICULT.
SO...THE GOING FORECAST IS IN REASONABLY SOUND SHAPE...WITH CHANCE
POPS BEGINNING ABOUT NOW IN PARTS OF EASTERN UPPER...AND EXPANDING
SE-WARD INTO NW AND N CENTRAL LOWER LATE. TEMPS WILL BE
MILD...WITH ONLY SMALL ADJUSTMENTS NEEDED.
UPDATE ISSUED AT 742 PM EDT SUN MAY 19 2013
RECENTLY DEVELOPED CU FIELD HAS DECIDED TO BE RATHER
TRANSIENT...RACING OFF INTO N CENTRAL LOWER MI. THERE ARE SOME CU
LINES LEFT BEHIND IN NW LOWER. THERE IS PERHAPS A VERY SLIGHT
CHANCE FOR THESE TO DEVELOP INTO CONVECTION BETWEEN 00Z AND 03Z IF
THE CAP WEAKENS AS MUCH AS PROGGED BY THE NAM (SEE EARLIER
UPDATE). WILL CONTINUE TO CHASE CLOUD TRENDS...OTHERWISE NO
CHANGES.
UPDATE ISSUED AT 635 PM EDT SUN MAY 19 2013
SOME INTERESTING TRENDS OVER THE LAST HOUR OR SO. 1ST...CU FIELD
OVER THE INTERIOR OF NORTHERN LOWER MI CONTINUES TO DIMINISH...NOW
LARGELY CONFINED TO MIO AND THE SURROUNDING AREA. RAPIDLY RUNNING
OUT OF TIME TO SEE ANYTHING FIRE THERE.
2ND...A HIGH-BASED CU FIELD HAS RAPIDLY DEVELOPED ALONG THE LAKE
MI COAST WEST OF TVC OVER THE PAST HOUR. OBVIOUSLY NOT DIRECTLY
ASSOCIATED WITH DIURNAL HEATING...GIVEN THE LOCATION OVER THE
MARINE LAYER. A FEW SHORT-TERM MODEL SOUNDINGS (LED OF COURSE BY
THE NAM) ARE SHOWING ENOUGH MOISTURE ADVECTION INTO THE 850-800MB
LAYER TO PRODUCE SATURATION. THE NAM ALSO LEADS THE WAY IN THE
RESULTING ELEVATED INSTABILITY...WITH MUCAPES NEARING 1K J/KG BY
03Z...AND A WEAKENING OF THE CAP (10C 750MB TEMPS OFF THE NAM...12C
FROM THE RUC/LOCAL WRF). THOUGH THE NAM IS MOIST TO A FAULT...IT
DOES AT LEAST REFLECT THE CLOUD DEVELOPMENT THAT WE ARE SEEING IN
THE AREA. AND IT WOULD SUGGEST THAT ANY SORT OF WEAK IMPULSE
(SAY...EXPELLED BY THE DYING CLUSTER OF CONVECTION NEAR LK
WINNEBAGO) MIGHT KICK SOMETHING OFF.
AM INCREASING CLOUD COVER...BUT /FOR NOW/ WILL NOT INTRODUCE POPS
ANY EARLIER THAN IS ALREADY IN THE FORECAST (06Z/2AM).
HOWEVER...WILL TAKE A VERY CLOSE LOOK AT 00Z GRB/APX SOUNDINGS AND
OTHER DATA THAT IS SOON TO ARRIVE...IN PARTICULAR LOOKING AT HOW
THE CAP MIGHT BEHAVE THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
POSSIBLY AN ISOLATED EARLY EVENING SHOWER OVER INTERIOR AREAS MAINLY
INVOF LAKE BREEZE BOUNDARIES. THESE SHOULD DISSIPATE EARLY WITH LOSS
OF DAYTIME HEATING. AN ELEVATED WARM FRONT LIFTS THROUGH THE REGION
LATE TONIGHT /AFTER 06Z/...WITH SURFACE FRONTAL BOUNDARY DRAPED
ACROSS THE AREA. UNIMPRESSIVE KINEMATICS...WITH BEST FORCING
REMAINING WEST OF THE AREA CLOSER TO UPPER TROUGH. 850M THETA-E
RIDGE FOLDS OVER INTO THE AREA LATE TONIGHT WITH STEEPER MID LEVEL
LAPSE RATES AND MUCAPES OVER 500 J/KG. THIS ALL POINTS TO AT LEAST
A CHANCE OF THUNDER OVER NRN/WRN AREAS. FAIRLY MILD...WITH LOWS
IN THE 50S NORTH TO 60S SOUTH. WILL ALSO ADD FOG FOR LATER TONIGHT TO
NEARSHORE WATERS AND PORTIONS OF NORTHERN LOWER MICHIGAN...AS LOW
LEVEL MOISTURE CONTINUES TO INCREASE AND POOL INVOF BOUNDARY.
MONDAY...CHALLENGING FORECAST GIVEN QUESTIONABLE EVOLUTION OF
UPSTREAM CONVECTION. PRECIP CHANCES WILL CONTINUE TO INCREASE FROM
WEST TO EAST WITH FRONTAL BOUNDARY DRAPED ACROSS NRN LOWER
MICHIGAN. DEEPENING TROUGH/LOW PRESSURE IN THE PLAINS WILL BEGIN TO
TAP INTO GULF MOISTURE...ADVECTING DEEPER MOISTURE NORTHWARD THRU
THE LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES.
AS THIS DEEPER MOISTURE BEGINS TO INTERACT WITH FRONTAL BOUNDARY AND
A SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE
DEEPENING UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL
INCREASE. DIFFICULT TO PINPOINT EXACT DETAILS GIVEN UNCERTAINTY IN
FRONTAL LOCATION/CONVECTIVE EVOLUTION...BUT BROAD LARGE-SCALE ASCENT
ON THE ERN EDGE OF UPPER TROUGH AND AIRMASS DESTABILIZATION SHOULD
RESULT IN A GOOD CHANCE OF SHOWERS/STORMS FOR THE AFTN HOURS.
BACKWARD TRAJECTORY OF DWPTS SHOW PARCEL ORIGINATION FROM CENTRAL
INDIANA FOR MONDAY AFTN...WHICH BRINGS SFC DWPTS INTO THE LOWER
60S FOR PORTIONS OF THE AREA MONDAY AFTERNOON. MODIFYING FCST
SOUNDINGS FOR A PARCEL TEMP OF 79/62 YIELD SBCAPES OF 1200 J/KG.
WITH STEEPENING MID LEVEL LAPSE RATES ARRIVING OVER SOUTHWEST
AREAS LATE IN THE DAY AND STRONG BOUNDARY LAYER HEATING
/DESTABILIZATION/...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH
THE MAIN THREAT BEING LARGE HAIL. HIGH TEMPERATURES ANOTHER
CHALLENGE GIVEN CLOUD/PCPN UNCERTAINTY AND WILL BASICALLY TAKE A
MODEL BLEND...WHICH GIVES HIGHS IN THE UPPER 60S OVER ERN UPPER TO
THE LOWER 80S SOUTH. WITH ENOUGH SUNSHINE...TEMPS ALOFT CERTAINLY
WARM ENOUGH TO SUPPORT HIGH TEMPS IN THE MID 80S SOUTH OF M-72.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
INCREASINGLY AMPLIFIED AND SLOW MOVING PATTERN LOOKS TO LOCK IN A
RATHER WET PERIOD OF WEATHER RIGHT THROUGH MID-WEEK. IMPETUS BEHIND
THE RAINS WILL BE PERSISTENT MOISTURE RICH LOW AND MID LEVEL
CONVERGENCE ZONE LAYING OUT ACROSS THE AREA...ALL THE WHILE SLOW
MOVING CENTRAL PLAINS LOW SENDS VARIOUS POCKETS OF ENERGY UP ALONG
IT. FROM A CONCEPTUAL STANDPOINT...MOISTURE SUPPLY LOOKS RATHER
IDEAL...WITH WIDE OPEN GULF OF MEXICO MOISTURE FEED SPIKING PWAT
VALUES UP TO AND EXCEEDING AN INCH AND A HALF RIGHT THROUGH
WEDNESDAY. THAT SAID...CONVECTIVE SEASON NOW IN OVERDRIVE TO OUR
SOUTH AND SOUTHWEST...AND WILL NO DOUBT HAVE PLENTY TO SAY ON THE
OVERALL EVOLUTION OF THIS EVENT. EARLY MEMORIAL DAY WEEKEND GUIDANCE
TRENDS CONTINUE TO INDICATE DEVELOPMENT OF RATHER DEEP WEST/EAST
COAST TROUGHS...WITH HIGH PLAINS RIDGING TUCKED UP IN-BETWEEN. THIS
SHOULD...THEORETICALLY...OPEN THE DOOR FOR A SHOT OF RATHER COOL
CANADIAN AIR AND PERHAPS THE POTENTIALLY FOR ANOTHER OVERNIGHT FROST
EVENT...ESPECIALLY FOR FRIDAY NIGHT. ABOVE YIELDS PLENTY TO TALK
ABOUT...WITH MUCH OF THE FOCUS CENTERED ON IMPENDING WET WEATHER AND
SEVERE WEATHER POTENTIAL.
AS MENTIONED...UPCOMING SET-UP LOOKS RATHER FAVORABLE FOR SOME MUCH
NEEDED RAINS...WITH PERSISTENT MOIST SOUTH FLOW ON FRONT SIDE OF
SLOW MOVING CENTRAL PLAIN LOW PRESSURE INTERSECTING LOW/MID LEVEL
BAROCLINIC AXIS. SURFACE WARM FRONT LOOKS TO GRADUALLY MIX SOUTH
MONDAY NIGHT...AIDED BY COLD LAKE WATERS AND PERIODIC BOUTS OF
CONVECTION...BEFORE PERHAPS BEING PROPELLED BACK NORTH TUESDAY INTO
WEDNESDAY WITH APPROACH OF PRIMARY UPSTREAM WAVE. HARD TO TIME
PERIODS OF BETTER SHOWER AND STORM POTENTIAL...ESPECIALLY WITH
UPSTREAM CONVECTIVE TRENDS AND TIMING OF VARIOUS IMPULSES DICTATING
SUCH. DESPITE PERSISTENCE FOR RAINS SEEN IN GUIDANCE...PREFER TO
KEEP JUST LIKELY WORDING IN THE FORECAST (LEARNED UP HERE TO
NEVER...NEVER TRUST CONVECTION). INITIAL SEVERE THREAT SHOULD REMAIN
TO OUR SOUTHWEST MONDAY NIGHT WHERE MORE PRONOUNCED LOW LEVEL
INSTABILITY AXIS AND DEEPER SHEAR ARE BETTER JUXTAPOSED. INCREASING
CONCERN FOR AT LEAST A MINIMAL SEVERE THREAT HEADING INTO TUESDAY
AND WEDNESDAY AS SURFACE WARM FRONT KICKS BACK NORTH...PERHAPS
REACHING AS FAR NORTH AS THE STRAITS BY WEDNESDAY. MUCH TOO EARLY TO
GET TOO SPECIFIC...BUT NORTHWARD SURGING WARM FRONT ITSELF IS
DISCONCERTING...AS IS POTENTIALLY BREAKING INTO THE WARM SECTOR FOR
AT LEAST PARTS OF THE AREA. MUCH...OF COURSE...WILL DEPEND ON
UPSTREAM CONVECTIVE EVOLUTION...BUT WOULD NOT BE AT ALL SURPRISED TO
SEE OUR FIRST SEVERE THUNDERSTORM EVENT OF THE SEASON (AND ENDING
ONE OF THE LATEST STARTS TO SUCH IN OUR RECENT HISTORY). OVERNIGHT
ISSUED SPC SEVERE GRAPHICS CONCUR...BRINGING TUESDAY INTO WEDNESDAY
SLIGHT RISK CATEGORY UP TO ABOUT M-32. DEFINITELY SOMETHING TO
MONITOR IN THE COMING DAYS...BUT WILL DEFER INTRODUCING THIS THREAT
IN THE LATEST RENDITION OF THE HAZARDOUS WEATHER OUTLOOK UNTIL
BETTER CONFIDENCE IS REALIZED. FORECASTING TEMPERATURES EVEN A MUCH
LOWER CONFIDENCE ENDEAVOR THAN ALL THE ABOVE. WILL SIMPLY USE A
CONSENSUS APPROACH FOR NOW...AND WILL HONESTLY STATE FORECAST WILL
LIKELY IN NO WAY MIMIC REALITY.
MID LEVEL LOW OPENS UP AS IT PASSES OVERHEAD LATER WEDNESDAY AND
WEDNESDAY NIGHT (TIMING SUBJECT TO CHANGE...OF COURSE)...EVENTUALLY
BECOMING ABSORBED IN DEEPENING EASTERN TROUGH TO END THE WEEK. RAINS
LOOK TO CONTINUE WEDNESDAY NIGHT...PERHAPS LINGERING INTO THURSDAY.
START OF THE HOLIDAY WEEKEND CONTINUES TO LOOK DRY AND SEASONABLY
COOL AS STRONG CANADIAN HIGH PRESSURE BUILDS SOUTH FRIDAY AND
SATURDAY BETWEEN EASTERN TROUGHING AND HIGH PLAIN RIDGING. HIGHS
TEMPERATURES NOT EXCEPTIONALLY COOL...BUT STILL A FEW DEGREES BELOW
NORMAL...WITH READINGS FRIDAY IN THE UPPER 50S AND LOWER
60S....WARMING SLIGHTLY INTO THE 60S FOR SATURDAY. BIGGER CONCERN
REMAINS FOR SOME RATHER CHILLY OVERNIGHT LOWS. COULD SEE SOME
READINGS DIP INTO THE MIDDLE AND UPPER 30S AS QUICKLY AS THURSDAY
NIGHT...DRIVEN SIMPLY BY SHOT OF CAA ON NORTHEAST TO NORTH WINDS.
PER PATTERN RECOGNITION...FRIDAY NIGHT CONTINUES TO LOOK DOWNRIGHT
CHILLY WITH COOL HIGH PRESSURE AND ATTENDANT DRY AIR CENTERED
DIRECTLY OVERHEAD. DESPITE BEING AT LEAST PARTIALLY CLIMATOLOGICALLY
INFLUENCED AT THIS TIME FRAME...LATEST ECMWF MOS PROGS CONTINUE TO
LOOK RATHER DISCONCERTING...FEATURING WIDESPREAD LOWER AND MIDDLE 30
DEGREE READINGS BY EARLY SATURDAY MORNING (GFS MEX PROGS ALSO
TRENDING COOLER...ALTHOUGH NOT YET TO THIS EXTREME). WILL START THE
PROCESS OF TRENDING COOLER THROUGH THIS PERIOD AND INTRODUCE THE
MENTION OF THIS FROST POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK FOR
NORTHERN LOWER MICHIGAN (FROST/FREEZE SEASON DOESN`T KICK OFF FOR
UPPER MICHIGAN UNTIL MEMORIAL DAY). JUST TOOK A QUICK PERUSAL OF
LATEST 12Z ECMWF...WHICH HAS TRENDED MUCH STRONGER WITH CAA THURSDAY
NIGHT THROUGH SUNDAY. IF THIS IS REALIZED...HIGHS FRIDAY WILL LIKELY
BE STUCK IN THE 50S...WITH OVERNIGHT LOWS RANGING FROM THE MID AND
UPPER 30S THURSDAY NIGHT AND AGAIN SATURDAY NIGHT...WITH WIDESPREAD
UPPER 20 TO MID 30 DEGREE READINGS FRIDAY NIGHT. QUESTIONS ABOUND BY
SUNDAY...WITH SOME POTENTIAL FOR DEVELOPING WAA TO KICK OFF AT LEAST
THE THREAT FOR A FEW SHOWERS. IN NO HURRY TO INTRODUCE THIS JUST YET
GIVEN INHERENT TIMING CONCERNS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 742 PM EDT SUN MAY 19 2013
MOSTLY VFR...THOUGH THE CHANCE FOR BRIEF RESTRICTIONS DUE TO
SHRA/TSRA WILL INCREASE THRU THE FORECAST. ALSO A SLIGHT CHANCE
FOR FOG LATE TONIGHT.
IN ADVANCE OF A COMPLEX LOW PRESSURE SYSTEM IN THE PLAINS...WARMER
AND MORE HUMID AIR CONTINUES TO GRADUALLY WORK NORTHWARD INTO MI.
THE CHANCE FOR THIS AIRMASS TO PRODUCE SHRA/TSRA WILL
INCREASE...AND ESPECIALLY ON MONDAY AFTERNOON. HAVE INTRODUCED
VCTS INTO ALL TAFS FOR A FEW HOURS. THERE ARE SMALLER CHANCE FOR
PRECIP EVEN BEFORE THAT...BUT THESE CHANCES ARE NOT HIGH ENOUGH TO
WARRANT MENTION IN THE TAFS AT THIS TIME.
SOME POTENTIAL FOR VSBYS RESTRICTIONS IN BR LATE TONIGHT...AND 06Z
TAFS COULD SEE SOME TEMPO GROUPS INTRODUCED TO ACCOUNT FOR THIS.
LIGHT WINDS TONIGHT...BECOMING SOMEWHAT BREEZY FROM THE EAST AT
APN/PLN MONDAY...LESS BLUSTERY FROM THE SOUTH TVC/MBL.
&&
.MARINE...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY THRU TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JZ
MARINE...JK
000
FXUS63 KAPX 192342
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
742 PM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.UPDATE...
ISSUED AT 742 PM EDT SUN MAY 19 2013
RECENTLY DEVELOPED CU FIELD HAS DECIDED TO BE RATHER
TRANSIENT...RACING OFF INTO N CENTRAL LOWER MI. THERE ARE SOME CU
LINES LEFT BEHIND IN NW LOWER. THERE IS PERHAPS A VERY SLIGHT
CHANCE FOR THESE TO DEVELOP INTO CONVECTION BETWEEN 00Z AND 03Z IF
THE CAP WEAKENS AS MUCH AS PROGGED BY THE NAM (SEE EARLIER
UPDATE). WILL CONTINUE TO CHASE CLOUD TRENDS...OTHERWISE NO
CHANGES.
UPDATE ISSUED AT 635 PM EDT SUN MAY 19 2013
SOME INTERESTING TRENDS OVER THE LAST HOUR OR SO. 1ST...CU FIELD
OVER THE INTERIOR OF NORTHERN LOWER MI CONTINUES TO DIMINISH...NOW
LARGELY CONFINED TO MIO AND THE SURROUNDING AREA. RAPIDLY RUNNING
OUT OF TIME TO SEE ANYTHING FIRE THERE.
2ND...A HIGH-BASED CU FIELD HAS RAPIDLY DEVELOPED ALONG THE LAKE
MI COAST WEST OF TVC OVER THE PAST HOUR. OBVIOUSLY NOT DIRECTLY
ASSOCIATED WITH DIURNAL HEATING...GIVEN THE LOCATION OVER THE
MARINE LAYER. A FEW SHORT-TERM MODEL SOUNDINGS (LED OF COURSE BY
THE NAM) ARE SHOWING ENOUGH MOISTURE ADVECTION INTO THE 850-800MB
LAYER TO PRODUCE SATURATION. THE NAM ALSO LEADS THE WAY IN THE
RESULTING ELEVATED INSTABILITY...WITH MUCAPES NEARING 1K J/KG BY
03Z...AND A WEAKENING OF THE CAP (10C 750MB TEMPS OFF THE NAM...12C
FROM THE RUC/LOCAL WRF). THOUGH THE NAM IS MOIST TO A FAULT...IT
DOES AT LEAST REFLECT THE CLOUD DEVELOPMENT THAT WE ARE SEEING IN
THE AREA. AND IT WOULD SUGGEST THAT ANY SORT OF WEAK IMPULSE
(SAY...EXPELLED BY THE DYING CLUSTER OF CONVECTION NEAR LK
WINNEBAGO) MIGHT KICK SOMETHING OFF.
AM INCREASING CLOUD COVER...BUT /FOR NOW/ WILL NOT INTRODUCE POPS
ANY EARLIER THAN IS ALREADY IN THE FORECAST (06Z/2AM).
HOWEVER...WILL TAKE A VERY CLOSE LOOK AT 00Z GRB/APX SOUNDINGS AND
OTHER DATA THAT IS SOON TO ARRIVE...IN PARTICULAR LOOKING AT HOW
THE CAP MIGHT BEHAVE THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
POSSIBLY AN ISOLATED EARLY EVENING SHOWER OVER INTERIOR AREAS MAINLY
INVOF LAKE BREEZE BOUNDARIES. THESE SHOULD DISSIPATE EARLY WITH LOSS
OF DAYTIME HEATING. AN ELEVATED WARM FRONT LIFTS THROUGH THE REGION
LATE TONIGHT /AFTER 06Z/...WITH SURFACE FRONTAL BOUNDARY DRAPED
ACROSS THE AREA. UNIMPRESSIVE KINEMATICS...WITH BEST FORCING
REMAINING WEST OF THE AREA CLOSER TO UPPER TROUGH. 850M THETA-E
RIDGE FOLDS OVER INTO THE AREA LATE TONIGHT WITH STEEPER MID LEVEL
LAPSE RATES AND MUCAPES OVER 500 J/KG. THIS ALL POINTS TO AT LEAST
A CHANCE OF THUNDER OVER NRN/WRN AREAS. FAIRLY MILD...WITH LOWS
IN THE 50S NORTH TO 60S SOUTH. WILL ALSO ADD FOG FOR LATER TONIGHT TO
NEARSHORE WATERS AND PORTIONS OF NORTHERN LOWER MICHIGAN...AS LOW
LEVEL MOISTURE CONTINUES TO INCREASE AND POOL INVOF BOUNDARY.
MONDAY...CHALLENGING FORECAST GIVEN QUESTIONABLE EVOLUTION OF
UPSTREAM CONVECTION. PRECIP CHANCES WILL CONTINUE TO INCREASE FROM
WEST TO EAST WITH FRONTAL BOUNDARY DRAPED ACROSS NRN LOWER
MICHIGAN. DEEPENING TROUGH/LOW PRESSURE IN THE PLAINS WILL BEGIN TO
TAP INTO GULF MOISTURE...ADVECTING DEEPER MOISTURE NORTHWARD THRU
THE LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES.
AS THIS DEEPER MOISTURE BEGINS TO INTERACT WITH FRONTAL BOUNDARY AND
A SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE
DEEPENING UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL
INCREASE. DIFFICULT TO PINPOINT EXACT DETAILS GIVEN UNCERTAINTY IN
FRONTAL LOCATION/CONVECTIVE EVOLUTION...BUT BROAD LARGE-SCALE ASCENT
ON THE ERN EDGE OF UPPER TROUGH AND AIRMASS DESTABILIZATION SHOULD
RESULT IN A GOOD CHANCE OF SHOWERS/STORMS FOR THE AFTN HOURS.
BACKWARD TRAJECTORY OF DWPTS SHOW PARCEL ORIGINATION FROM CENTRAL
INDIANA FOR MONDAY AFTN...WHICH BRINGS SFC DWPTS INTO THE LOWER
60S FOR PORTIONS OF THE AREA MONDAY AFTERNOON. MODIFYING FCST
SOUNDINGS FOR A PARCEL TEMP OF 79/62 YIELD SBCAPES OF 1200 J/KG.
WITH STEEPENING MID LEVEL LAPSE RATES ARRIVING OVER SOUTHWEST
AREAS LATE IN THE DAY AND STRONG BOUNDARY LAYER HEATING
/DESTABILIZATION/...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH
THE MAIN THREAT BEING LARGE HAIL. HIGH TEMPERATURES ANOTHER
CHALLENGE GIVEN CLOUD/PCPN UNCERTAINTY AND WILL BASICALLY TAKE A
MODEL BLEND...WHICH GIVES HIGHS IN THE UPPER 60S OVER ERN UPPER TO
THE LOWER 80S SOUTH. WITH ENOUGH SUNSHINE...TEMPS ALOFT CERTAINLY
WARM ENOUGH TO SUPPORT HIGH TEMPS IN THE MID 80S SOUTH OF M-72.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
INCREASINGLY AMPLIFIED AND SLOW MOVING PATTERN LOOKS TO LOCK IN A
RATHER WET PERIOD OF WEATHER RIGHT THROUGH MID-WEEK. IMPETUS BEHIND
THE RAINS WILL BE PERSISTENT MOISTURE RICH LOW AND MID LEVEL
CONVERGENCE ZONE LAYING OUT ACROSS THE AREA...ALL THE WHILE SLOW
MOVING CENTRAL PLAINS LOW SENDS VARIOUS POCKETS OF ENERGY UP ALONG
IT. FROM A CONCEPTUAL STANDPOINT...MOISTURE SUPPLY LOOKS RATHER
IDEAL...WITH WIDE OPEN GULF OF MEXICO MOISTURE FEED SPIKING PWAT
VALUES UP TO AND EXCEEDING AN INCH AND A HALF RIGHT THROUGH
WEDNESDAY. THAT SAID...CONVECTIVE SEASON NOW IN OVERDRIVE TO OUR
SOUTH AND SOUTHWEST...AND WILL NO DOUBT HAVE PLENTY TO SAY ON THE
OVERALL EVOLUTION OF THIS EVENT. EARLY MEMORIAL DAY WEEKEND GUIDANCE
TRENDS CONTINUE TO INDICATE DEVELOPMENT OF RATHER DEEP WEST/EAST
COAST TROUGHS...WITH HIGH PLAINS RIDGING TUCKED UP IN-BETWEEN. THIS
SHOULD...THEORETICALLY...OPEN THE DOOR FOR A SHOT OF RATHER COOL
CANADIAN AIR AND PERHAPS THE POTENTIALLY FOR ANOTHER OVERNIGHT FROST
EVENT...ESPECIALLY FOR FRIDAY NIGHT. ABOVE YIELDS PLENTY TO TALK
ABOUT...WITH MUCH OF THE FOCUS CENTERED ON IMPENDING WET WEATHER AND
SEVERE WEATHER POTENTIAL.
AS MENTIONED...UPCOMING SET-UP LOOKS RATHER FAVORABLE FOR SOME MUCH
NEEDED RAINS...WITH PERSISTENT MOIST SOUTH FLOW ON FRONT SIDE OF
SLOW MOVING CENTRAL PLAIN LOW PRESSURE INTERSECTING LOW/MID LEVEL
BAROCLINIC AXIS. SURFACE WARM FRONT LOOKS TO GRADUALLY MIX SOUTH
MONDAY NIGHT...AIDED BY COLD LAKE WATERS AND PERIODIC BOUTS OF
CONVECTION...BEFORE PERHAPS BEING PROPELLED BACK NORTH TUESDAY INTO
WEDNESDAY WITH APPROACH OF PRIMARY UPSTREAM WAVE. HARD TO TIME
PERIODS OF BETTER SHOWER AND STORM POTENTIAL...ESPECIALLY WITH
UPSTREAM CONVECTIVE TRENDS AND TIMING OF VARIOUS IMPULSES DICTATING
SUCH. DESPITE PERSISTENCE FOR RAINS SEEN IN GUIDANCE...PREFER TO
KEEP JUST LIKELY WORDING IN THE FORECAST (LEARNED UP HERE TO
NEVER...NEVER TRUST CONVECTION). INITIAL SEVERE THREAT SHOULD REMAIN
TO OUR SOUTHWEST MONDAY NIGHT WHERE MORE PRONOUNCED LOW LEVEL
INSTABILITY AXIS AND DEEPER SHEAR ARE BETTER JUXTAPOSED. INCREASING
CONCERN FOR AT LEAST A MINIMAL SEVERE THREAT HEADING INTO TUESDAY
AND WEDNESDAY AS SURFACE WARM FRONT KICKS BACK NORTH...PERHAPS
REACHING AS FAR NORTH AS THE STRAITS BY WEDNESDAY. MUCH TOO EARLY TO
GET TOO SPECIFIC...BUT NORTHWARD SURGING WARM FRONT ITSELF IS
DISCONCERTING...AS IS POTENTIALLY BREAKING INTO THE WARM SECTOR FOR
AT LEAST PARTS OF THE AREA. MUCH...OF COURSE...WILL DEPEND ON
UPSTREAM CONVECTIVE EVOLUTION...BUT WOULD NOT BE AT ALL SURPRISED TO
SEE OUR FIRST SEVERE THUNDERSTORM EVENT OF THE SEASON (AND ENDING
ONE OF THE LATEST STARTS TO SUCH IN OUR RECENT HISTORY). OVERNIGHT
ISSUED SPC SEVERE GRAPHICS CONCUR...BRINGING TUESDAY INTO WEDNESDAY
SLIGHT RISK CATEGORY UP TO ABOUT M-32. DEFINITELY SOMETHING TO
MONITOR IN THE COMING DAYS...BUT WILL DEFER INTRODUCING THIS THREAT
IN THE LATEST RENDITION OF THE HAZARDOUS WEATHER OUTLOOK UNTIL
BETTER CONFIDENCE IS REALIZED. FORECASTING TEMPERATURES EVEN A MUCH
LOWER CONFIDENCE ENDEAVOR THAN ALL THE ABOVE. WILL SIMPLY USE A
CONSENSUS APPROACH FOR NOW...AND WILL HONESTLY STATE FORECAST WILL
LIKELY IN NO WAY MIMIC REALITY.
MID LEVEL LOW OPENS UP AS IT PASSES OVERHEAD LATER WEDNESDAY AND
WEDNESDAY NIGHT (TIMING SUBJECT TO CHANGE...OF COURSE)...EVENTUALLY
BECOMING ABSORBED IN DEEPENING EASTERN TROUGH TO END THE WEEK. RAINS
LOOK TO CONTINUE WEDNESDAY NIGHT...PERHAPS LINGERING INTO THURSDAY.
START OF THE HOLIDAY WEEKEND CONTINUES TO LOOK DRY AND SEASONABLY
COOL AS STRONG CANADIAN HIGH PRESSURE BUILDS SOUTH FRIDAY AND
SATURDAY BETWEEN EASTERN TROUGHING AND HIGH PLAIN RIDGING. HIGHS
TEMPERATURES NOT EXCEPTIONALLY COOL...BUT STILL A FEW DEGREES BELOW
NORMAL...WITH READINGS FRIDAY IN THE UPPER 50S AND LOWER
60S....WARMING SLIGHTLY INTO THE 60S FOR SATURDAY. BIGGER CONCERN
REMAINS FOR SOME RATHER CHILLY OVERNIGHT LOWS. COULD SEE SOME
READINGS DIP INTO THE MIDDLE AND UPPER 30S AS QUICKLY AS THURSDAY
NIGHT...DRIVEN SIMPLY BY SHOT OF CAA ON NORTHEAST TO NORTH WINDS.
PER PATTERN RECOGNITION...FRIDAY NIGHT CONTINUES TO LOOK DOWNRIGHT
CHILLY WITH COOL HIGH PRESSURE AND ATTENDANT DRY AIR CENTERED
DIRECTLY OVERHEAD. DESPITE BEING AT LEAST PARTIALLY CLIMATOLOGICALLY
INFLUENCED AT THIS TIME FRAME...LATEST ECMWF MOS PROGS CONTINUE TO
LOOK RATHER DISCONCERTING...FEATURING WIDESPREAD LOWER AND MIDDLE 30
DEGREE READINGS BY EARLY SATURDAY MORNING (GFS MEX PROGS ALSO
TRENDING COOLER...ALTHOUGH NOT YET TO THIS EXTREME). WILL START THE
PROCESS OF TRENDING COOLER THROUGH THIS PERIOD AND INTRODUCE THE
MENTION OF THIS FROST POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK FOR
NORTHERN LOWER MICHIGAN (FROST/FREEZE SEASON DOESN`T KICK OFF FOR
UPPER MICHIGAN UNTIL MEMORIAL DAY). JUST TOOK A QUICK PERUSAL OF
LATEST 12Z ECMWF...WHICH HAS TRENDED MUCH STRONGER WITH CAA THURSDAY
NIGHT THROUGH SUNDAY. IF THIS IS REALIZED...HIGHS FRIDAY WILL LIKELY
BE STUCK IN THE 50S...WITH OVERNIGHT LOWS RANGING FROM THE MID AND
UPPER 30S THURSDAY NIGHT AND AGAIN SATURDAY NIGHT...WITH WIDESPREAD
UPPER 20 TO MID 30 DEGREE READINGS FRIDAY NIGHT. QUESTIONS ABOUND BY
SUNDAY...WITH SOME POTENTIAL FOR DEVELOPING WAA TO KICK OFF AT LEAST
THE THREAT FOR A FEW SHOWERS. IN NO HURRY TO INTRODUCE THIS JUST YET
GIVEN INHERENT TIMING CONCERNS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 742 PM EDT SUN MAY 19 2013
MOSTLY VFR...THOUGH THE CHANCE FOR BRIEF RESTRICTIONS DUE TO
SHRA/TSRA WILL INCREASE THRU THE FORECAST. ALSO A SLIGHT CHANCE
FOR FOG LATE TONIGHT.
IN ADVANCE OF A COMPLEX LOW PRESSURE SYSTEM IN THE PLAINS...WARMER
AND MORE HUMID AIR CONTINUES TO GRADUALLY WORK NORTHWARD INTO MI.
THE CHANCE FOR THIS AIRMASS TO PRODUCE SHRA/TSRA WILL
INCREASE...AND ESPECIALLY ON MONDAY AFTERNOON. HAVE INTRODUCED
VCTS INTO ALL TAFS FOR A FEW HOURS. THERE ARE SMALLER CHANCE FOR
PRECIP EVEN BEFORE THAT...BUT THESE CHANCES ARE NOT HIGH ENOUGH TO
WARRANT MENTION IN THE TAFS AT THIS TIME.
SOME POTENTIAL FOR VSBYS RESTRICTIONS IN BR LATE TONIGHT...AND 06Z
TAFS COULD SEE SOME TEMPO GROUPS INTRODUCED TO ACCOUNT FOR THIS.
LIGHT WINDS TONIGHT...BECOMING SOMEWHAT BREEZY FROM THE EAST AT
APN/PLN MONDAY...LESS BLUSTERY FROM THE SOUTH TVC/MBL.
&&
.MARINE...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY THRU TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JZ
MARINE...JK
000
FXUS63 KAPX 192235
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
635 PM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.UPDATE...
ISSUED AT 635 PM EDT SUN MAY 19 2013
SOME INTERESTING TRENDS OVER THE LAST HOUR OR SO. 1ST...CU FIELD
OVER THE INTERIOR OF NORTHERN LOWER MI CONTINUES TO DIMINISH...NOW
LARGELY CONFINED TO MIO AND THE SURROUNDING AREA. RAPIDLY RUNNING
OUT OF TIME TO SEE ANYTHING FIRE THERE.
2ND...A HIGH-BASED CU FIELD HAS RAPIDLY DEVELOPED ALONG THE LAKE
MI COAST WEST OF TVC OVER THE PAST HOUR. OBVIOUSLY NOT DIRECTLY
ASSOCIATED WITH DIURNAL HEATING...GIVEN THE LOCATION OVER THE
MARINE LAYER. A FEW SHORT-TERM MODEL SOUNDINGS (LED OF COURSE BY
THE NAM) ARE SHOWING ENOUGH MOISTURE ADVECTION INTO THE 850-800MB
LAYER TO PRODUCE SATURATION. THE NAM ALSO LEADS THE WAY IN THE
RESULTING ELEVATED INSTABILITY...WITH MUCAPES NEARING 1K J/KG BY
03Z...AND A WEAKENING OF THE CAP (10C 750MB TEMPS OFF THE NAM...12C
FROM THE RUC/LOCAL WRF). THOUGH THE NAM IS MOIST TO A FAULT...IT
DOES AT LEAST REFLECT THE CLOUD DEVELOPMENT THAT WE ARE SEEING IN
THE AREA. AND IT WOULD SUGGEST THAT ANY SORT OF WEAK IMPULSE
(SAY...EXPELLED BY THE DYING CLUSTER OF CONVECTION NEAR LK
WINNEBAGO) MIGHT KICK SOMETHING OFF.
AM INCREASING CLOUD COVER...BUT /FOR NOW/ WILL NOT INTRODUCE POPS
ANY EARLIER THAN IS ALREADY IN THE FORECAST (06Z/2AM).
HOWEVER...WILL TAKE A VERY CLOSE LOOK AT 00Z GRB/APX SOUNDINGS AND
OTHER DATA THAT IS SOON TO ARRIVE...IN PARTICULAR LOOKING AT HOW
THE CAP MIGHT BEHAVE THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
POSSIBLY AN ISOLATED EARLY EVENING SHOWER OVER INTERIOR AREAS MAINLY
INVOF LAKE BREEZE BOUNDARIES. THESE SHOULD DISSIPATE EARLY WITH LOSS
OF DAYTIME HEATING. AN ELEVATED WARM FRONT LIFTS THROUGH THE REGION
LATE TONIGHT /AFTER 06Z/...WITH SURFACE FRONTAL BOUNDARY DRAPED
ACROSS THE AREA. UNIMPRESSIVE KINEMATICS...WITH BEST FORCING
REMAINING WEST OF THE AREA CLOSER TO UPPER TROUGH. 850M THETA-E
RIDGE FOLDS OVER INTO THE AREA LATE TONIGHT WITH STEEPER MID LEVEL
LAPSE RATES AND MUCAPES OVER 500 J/KG. THIS ALL POINTS TO AT LEAST
A CHANCE OF THUNDER OVER NRN/WRN AREAS. FAIRLY MILD...WITH LOWS
IN THE 50S NORTH TO 60S SOUTH. WILL ALSO ADD FOG FOR LATER TONIGHT TO
NEARSHORE WATERS AND PORTIONS OF NORTHERN LOWER MICHIGAN...AS LOW
LEVEL MOISTURE CONTINUES TO INCREASE AND POOL INVOF BOUNDARY.
MONDAY...CHALLENGING FORECAST GIVEN QUESTIONABLE EVOLUTION OF
UPSTREAM CONVECTION. PRECIP CHANCES WILL CONTINUE TO INCREASE FROM
WEST TO EAST WITH FRONTAL BOUNDARY DRAPED ACROSS NRN LOWER
MICHIGAN. DEEPENING TROUGH/LOW PRESSURE IN THE PLAINS WILL BEGIN TO
TAP INTO GULF MOISTURE...ADVECTING DEEPER MOISTURE NORTHWARD THRU
THE LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES.
AS THIS DEEPER MOISTURE BEGINS TO INTERACT WITH FRONTAL BOUNDARY AND
A SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE
DEEPENING UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL
INCREASE. DIFFICULT TO PINPOINT EXACT DETAILS GIVEN UNCERTAINTY IN
FRONTAL LOCATION/CONVECTIVE EVOLUTION...BUT BROAD LARGE-SCALE ASCENT
ON THE ERN EDGE OF UPPER TROUGH AND AIRMASS DESTABILIZATION SHOULD
RESULT IN A GOOD CHANCE OF SHOWERS/STORMS FOR THE AFTN HOURS.
BACKWARD TRAJECTORY OF DWPTS SHOW PARCEL ORIGINATION FROM CENTRAL
INDIANA FOR MONDAY AFTN...WHICH BRINGS SFC DWPTS INTO THE LOWER
60S FOR PORTIONS OF THE AREA MONDAY AFTERNOON. MODIFYING FCST
SOUNDINGS FOR A PARCEL TEMP OF 79/62 YIELD SBCAPES OF 1200 J/KG.
WITH STEEPENING MID LEVEL LAPSE RATES ARRIVING OVER SOUTHWEST
AREAS LATE IN THE DAY AND STRONG BOUNDARY LAYER HEATING
/DESTABILIZATION/...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH
THE MAIN THREAT BEING LARGE HAIL. HIGH TEMPERATURES ANOTHER
CHALLENGE GIVEN CLOUD/PCPN UNCERTAINTY AND WILL BASICALLY TAKE A
MODEL BLEND...WHICH GIVES HIGHS IN THE UPPER 60S OVER ERN UPPER TO
THE LOWER 80S SOUTH. WITH ENOUGH SUNSHINE...TEMPS ALOFT CERTAINLY
WARM ENOUGH TO SUPPORT HIGH TEMPS IN THE MID 80S SOUTH OF M-72.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
INCREASINGLY AMPLIFIED AND SLOW MOVING PATTERN LOOKS TO LOCK IN A
RATHER WET PERIOD OF WEATHER RIGHT THROUGH MID-WEEK. IMPETUS BEHIND
THE RAINS WILL BE PERSISTENT MOISTURE RICH LOW AND MID LEVEL
CONVERGENCE ZONE LAYING OUT ACROSS THE AREA...ALL THE WHILE SLOW
MOVING CENTRAL PLAINS LOW SENDS VARIOUS POCKETS OF ENERGY UP ALONG
IT. FROM A CONCEPTUAL STANDPOINT...MOISTURE SUPPLY LOOKS RATHER
IDEAL...WITH WIDE OPEN GULF OF MEXICO MOISTURE FEED SPIKING PWAT
VALUES UP TO AND EXCEEDING AN INCH AND A HALF RIGHT THROUGH
WEDNESDAY. THAT SAID...CONVECTIVE SEASON NOW IN OVERDRIVE TO OUR
SOUTH AND SOUTHWEST...AND WILL NO DOUBT HAVE PLENTY TO SAY ON THE
OVERALL EVOLUTION OF THIS EVENT. EARLY MEMORIAL DAY WEEKEND GUIDANCE
TRENDS CONTINUE TO INDICATE DEVELOPMENT OF RATHER DEEP WEST/EAST
COAST TROUGHS...WITH HIGH PLAINS RIDGING TUCKED UP IN-BETWEEN. THIS
SHOULD...THEORETICALLY...OPEN THE DOOR FOR A SHOT OF RATHER COOL
CANADIAN AIR AND PERHAPS THE POTENTIALLY FOR ANOTHER OVERNIGHT FROST
EVENT...ESPECIALLY FOR FRIDAY NIGHT. ABOVE YIELDS PLENTY TO TALK
ABOUT...WITH MUCH OF THE FOCUS CENTERED ON IMPENDING WET WEATHER AND
SEVERE WEATHER POTENTIAL.
AS MENTIONED...UPCOMING SET-UP LOOKS RATHER FAVORABLE FOR SOME MUCH
NEEDED RAINS...WITH PERSISTENT MOIST SOUTH FLOW ON FRONT SIDE OF
SLOW MOVING CENTRAL PLAIN LOW PRESSURE INTERSECTING LOW/MID LEVEL
BAROCLINIC AXIS. SURFACE WARM FRONT LOOKS TO GRADUALLY MIX SOUTH
MONDAY NIGHT...AIDED BY COLD LAKE WATERS AND PERIODIC BOUTS OF
CONVECTION...BEFORE PERHAPS BEING PROPELLED BACK NORTH TUESDAY INTO
WEDNESDAY WITH APPROACH OF PRIMARY UPSTREAM WAVE. HARD TO TIME
PERIODS OF BETTER SHOWER AND STORM POTENTIAL...ESPECIALLY WITH
UPSTREAM CONVECTIVE TRENDS AND TIMING OF VARIOUS IMPULSES DICTATING
SUCH. DESPITE PERSISTENCE FOR RAINS SEEN IN GUIDANCE...PREFER TO
KEEP JUST LIKELY WORDING IN THE FORECAST (LEARNED UP HERE TO
NEVER...NEVER TRUST CONVECTION). INITIAL SEVERE THREAT SHOULD REMAIN
TO OUR SOUTHWEST MONDAY NIGHT WHERE MORE PRONOUNCED LOW LEVEL
INSTABILITY AXIS AND DEEPER SHEAR ARE BETTER JUXTAPOSED. INCREASING
CONCERN FOR AT LEAST A MINIMAL SEVERE THREAT HEADING INTO TUESDAY
AND WEDNESDAY AS SURFACE WARM FRONT KICKS BACK NORTH...PERHAPS
REACHING AS FAR NORTH AS THE STRAITS BY WEDNESDAY. MUCH TOO EARLY TO
GET TOO SPECIFIC...BUT NORTHWARD SURGING WARM FRONT ITSELF IS
DISCONCERTING...AS IS POTENTIALLY BREAKING INTO THE WARM SECTOR FOR
AT LEAST PARTS OF THE AREA. MUCH...OF COURSE...WILL DEPEND ON
UPSTREAM CONVECTIVE EVOLUTION...BUT WOULD NOT BE AT ALL SURPRISED TO
SEE OUR FIRST SEVERE THUNDERSTORM EVENT OF THE SEASON (AND ENDING
ONE OF THE LATEST STARTS TO SUCH IN OUR RECENT HISTORY). OVERNIGHT
ISSUED SPC SEVERE GRAPHICS CONCUR...BRINGING TUESDAY INTO WEDNESDAY
SLIGHT RISK CATEGORY UP TO ABOUT M-32. DEFINITELY SOMETHING TO
MONITOR IN THE COMING DAYS...BUT WILL DEFER INTRODUCING THIS THREAT
IN THE LATEST RENDITION OF THE HAZARDOUS WEATHER OUTLOOK UNTIL
BETTER CONFIDENCE IS REALIZED. FORECASTING TEMPERATURES EVEN A MUCH
LOWER CONFIDENCE ENDEAVOR THAN ALL THE ABOVE. WILL SIMPLY USE A
CONSENSUS APPROACH FOR NOW...AND WILL HONESTLY STATE FORECAST WILL
LIKELY IN NO WAY MIMIC REALITY.
MID LEVEL LOW OPENS UP AS IT PASSES OVERHEAD LATER WEDNESDAY AND
WEDNESDAY NIGHT (TIMING SUBJECT TO CHANGE...OF COURSE)...EVENTUALLY
BECOMING ABSORBED IN DEEPENING EASTERN TROUGH TO END THE WEEK. RAINS
LOOK TO CONTINUE WEDNESDAY NIGHT...PERHAPS LINGERING INTO THURSDAY.
START OF THE HOLIDAY WEEKEND CONTINUES TO LOOK DRY AND SEASONABLY
COOL AS STRONG CANADIAN HIGH PRESSURE BUILDS SOUTH FRIDAY AND
SATURDAY BETWEEN EASTERN TROUGHING AND HIGH PLAIN RIDGING. HIGHS
TEMPERATURES NOT EXCEPTIONALLY COOL...BUT STILL A FEW DEGREES BELOW
NORMAL...WITH READINGS FRIDAY IN THE UPPER 50S AND LOWER
60S....WARMING SLIGHTLY INTO THE 60S FOR SATURDAY. BIGGER CONCERN
REMAINS FOR SOME RATHER CHILLY OVERNIGHT LOWS. COULD SEE SOME
READINGS DIP INTO THE MIDDLE AND UPPER 30S AS QUICKLY AS THURSDAY
NIGHT...DRIVEN SIMPLY BY SHOT OF CAA ON NORTHEAST TO NORTH WINDS.
PER PATTERN RECOGNITION...FRIDAY NIGHT CONTINUES TO LOOK DOWNRIGHT
CHILLY WITH COOL HIGH PRESSURE AND ATTENDANT DRY AIR CENTERED
DIRECTLY OVERHEAD. DESPITE BEING AT LEAST PARTIALLY CLIMATOLOGICALLY
INFLUENCED AT THIS TIME FRAME...LATEST ECMWF MOS PROGS CONTINUE TO
LOOK RATHER DISCONCERTING...FEATURING WIDESPREAD LOWER AND MIDDLE 30
DEGREE READINGS BY EARLY SATURDAY MORNING (GFS MEX PROGS ALSO
TRENDING COOLER...ALTHOUGH NOT YET TO THIS EXTREME). WILL START THE
PROCESS OF TRENDING COOLER THROUGH THIS PERIOD AND INTRODUCE THE
MENTION OF THIS FROST POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK FOR
NORTHERN LOWER MICHIGAN (FROST/FREEZE SEASON DOESN`T KICK OFF FOR
UPPER MICHIGAN UNTIL MEMORIAL DAY). JUST TOOK A QUICK PERUSAL OF
LATEST 12Z ECMWF...WHICH HAS TRENDED MUCH STRONGER WITH CAA THURSDAY
NIGHT THROUGH SUNDAY. IF THIS IS REALIZED...HIGHS FRIDAY WILL LIKELY
BE STUCK IN THE 50S...WITH OVERNIGHT LOWS RANGING FROM THE MID AND
UPPER 30S THURSDAY NIGHT AND AGAIN SATURDAY NIGHT...WITH WIDESPREAD
UPPER 20 TO MID 30 DEGREE READINGS FRIDAY NIGHT. QUESTIONS ABOUND BY
SUNDAY...WITH SOME POTENTIAL FOR DEVELOPING WAA TO KICK OFF AT LEAST
THE THREAT FOR A FEW SHOWERS. IN NO HURRY TO INTRODUCE THIS JUST YET
GIVEN INHERENT TIMING CONCERNS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1230 PM EDT SUN MAY 19 2013
VFR CONDITIONS WILL CONTINUE AT ALL NRN LWR MICHIGAN TAF SITES
THRU MONDAY MORNING. CHANCES OF SHOWERS AND STORMS WILL INCREASE
LATE TONIGHT INTO MONDAY MORNING AS A FRONT SAGS SOUTH INTO NRN LWR
MICHIGAN AND THE FIRST IN A SERIES OF SHORT WAVES ENTERS MICHIGAN
AHEAD OF LOW PRESSURE DEVELOPING IN THE PLAINS. WILL HANDLE PCPN
DEVELOPMENT WITH VCSH FOR NOW AND BETTER DEFINE TIMING OF PRECIP
AS THE EVENT DRAWS CLOSER. LIGHT SYNOPTIC FLOW WILL ALLOW FOR LAKE
BREEZE DEVELOPMENT THIS AFTERNOON.
&&
.MARINE...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY THRU TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JK
MARINE...JK
000
FXUS63 KAPX 191949
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
349 PM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A STORM SYSTEM WILL ORGANIZE OVER THE PLAINS...BEFORE MOVING INTO
THE GREAT LAKES TO START THE WORK WEEK. THIS APPROACHING SYSTEM WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS NORTHERN MICHIGAN THROUGH
MID WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
POSSIBLY AN ISOLATED EARLY EVENING SHOWER OVER INTERIOR AREAS MAINLY
INVOF LAKE BREEZE BOUNDARIES. THESE SHOULD DISSIPATE EARLY WITH LOSS
OF DAYTIME HEATING. AN ELEVATED WARM FRONT LIFTS THROUGH THE REGION
LATE TONIGHT /AFTER 06Z/...WITH SURFACE FRONTAL BOUNDARY DRAPED
ACROSS THE AREA. UNIMPRESSIVE KINEMATICS...WITH BEST FORCING
REMAINING WEST OF THE AREA CLOSER TO UPPER TROUGH. 850M THETA-E
RIDGE FOLDS OVER INTO THE AREA LATE TONIGHT WITH STEEPER MID LEVEL
LAPSE RATES AND MUCAPES OVER 500 J/KG. THIS ALL POINTS TO AT LEAST
A CHANCE OF THUNDER OVER NRN/WRN AREAS. FAIRLY MILD...WITH LOWS
IN THE 50S NORTH TO 60S SOUTH. WILL ALSO ADD FOG FOR LATER TONIGHT TO
NEARSHORE WATERS AND PORTIONS OF NORTHERN LOWER MICHIGAN...AS LOW
LEVEL MOISTURE CONTINUES TO INCREASE AND POOL INVOF BOUNDARY.
MONDAY...CHALLENGING FORECAST GIVEN QUESTIONABLE EVOLUTION OF
UPSTREAM CONVECTION. PRECIP CHANCES WILL CONTINUE TO INCREASE FROM
WEST TO EAST WITH FRONTAL BOUNDARY DRAPED ACROSS NRN LOWER
MICHIGAN. DEEPENING TROUGH/LOW PRESSURE IN THE PLAINS WILL BEGIN TO
TAP INTO GULF MOISTURE...ADVECTING DEEPER MOISTURE NORTHWARD THRU
THE LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES.
AS THIS DEEPER MOISTURE BEGINS TO INTERACT WITH FRONTAL BOUNDARY AND
A SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE
DEEPENING UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL
INCREASE. DIFFICULT TO PINPOINT EXACT DETAILS GIVEN UNCERTAINTY IN
FRONTAL LOCATION/CONVECTIVE EVOLUTION...BUT BROAD LARGE-SCALE ASCENT
ON THE ERN EDGE OF UPPER TROUGH AND AIRMASS DESTABILIZATION SHOULD
RESULT IN A GOOD CHANCE OF SHOWERS/STORMS FOR THE AFTN HOURS.
BACKWARD TRAJECTORY OF DWPTS SHOW PARCEL ORIGINATION FROM CENTRAL
INDIANA FOR MONDAY AFTN...WHICH BRINGS SFC DWPTS INTO THE LOWER
60S FOR PORTIONS OF THE AREA MONDAY AFTERNOON. MODIFYING FCST
SOUNDINGS FOR A PARCEL TEMP OF 79/62 YIELD SBCAPES OF 1200 J/KG.
WITH STEEPENING MID LEVEL LAPSE RATES ARRIVING OVER SOUTHWEST
AREAS LATE IN THE DAY AND STRONG BOUNDARY LAYER HEATING
/DESTABILIZATION/...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH
THE MAIN THREAT BEING LARGE HAIL. HIGH TEMPERATURES ANOTHER
CHALLENGE GIVEN CLOUD/PCPN UNCERTAINTY AND WILL BASICALLY TAKE A
MODEL BLEND...WHICH GIVES HIGHS IN THE UPPER 60S OVER ERN UPPER TO
THE LOWER 80S SOUTH. WITH ENOUGH SUNSHINE...TEMPS ALOFT CERTAINLY
WARM ENOUGH TO SUPPORT HIGH TEMPS IN THE MID 80S SOUTH OF M-72.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 340 PM EDT SUN MAY 19 2013
INCREASINGLY AMPLIFIED AND SLOW MOVING PATTERN LOOKS TO LOCK IN A
RATHER WET PERIOD OF WEATHER RIGHT THROUGH MID-WEEK. IMPETUS BEHIND
THE RAINS WILL BE PERSISTENT MOISTURE RICH LOW AND MID LEVEL
CONVERGENCE ZONE LAYING OUT ACROSS THE AREA...ALL THE WHILE SLOW
MOVING CENTRAL PLAINS LOW SENDS VARIOUS POCKETS OF ENERGY UP ALONG
IT. FROM A CONCEPTUAL STANDPOINT...MOISTURE SUPPLY LOOKS RATHER
IDEAL...WITH WIDE OPEN GULF OF MEXICO MOISTURE FEED SPIKING PWAT
VALUES UP TO AND EXCEEDING AN INCH AND A HALF RIGHT THROUGH
WEDNESDAY. THAT SAID...CONVECTIVE SEASON NOW IN OVERDRIVE TO OUR
SOUTH AND SOUTHWEST...AND WILL NO DOUBT HAVE PLENTY TO SAY ON THE
OVERALL EVOLUTION OF THIS EVENT. EARLY MEMORIAL DAY WEEKEND GUIDANCE
TRENDS CONTINUE TO INDICATE DEVELOPMENT OF RATHER DEEP WEST/EAST
COAST TROUGHS...WITH HIGH PLAINS RIDGING TUCKED UP IN-BETWEEN. THIS
SHOULD...THEORETICALLY...OPEN THE DOOR FOR A SHOT OF RATHER COOL
CANADIAN AIR AND PERHAPS THE POTENTIALLY FOR ANOTHER OVERNIGHT FROST
EVENT...ESPECIALLY FOR FRIDAY NIGHT. ABOVE YIELDS PLENTY TO TALK
ABOUT...WITH MUCH OF THE FOCUS CENTERED ON IMPENDING WET WEATHER AND
SEVERE WEATHER POTENTIAL.
AS MENTIONED...UPCOMING SET-UP LOOKS RATHER FAVORABLE FOR SOME MUCH
NEEDED RAINS...WITH PERSISTENT MOIST SOUTH FLOW ON FRONT SIDE OF
SLOW MOVING CENTRAL PLAIN LOW PRESSURE INTERSECTING LOW/MID LEVEL
BAROCLINIC AXIS. SURFACE WARM FRONT LOOKS TO GRADUALLY MIX SOUTH
MONDAY NIGHT...AIDED BY COLD LAKE WATERS AND PERIODIC BOUTS OF
CONVECTION...BEFORE PERHAPS BEING PROPELLED BACK NORTH TUESDAY INTO
WEDNESDAY WITH APPROACH OF PRIMARY UPSTREAM WAVE. HARD TO TIME
PERIODS OF BETTER SHOWER AND STORM POTENTIAL...ESPECIALLY WITH
UPSTREAM CONVECTIVE TRENDS AND TIMING OF VARIOUS IMPULSES DICTATING
SUCH. DESPITE PERSISTENCE FOR RAINS SEEN IN GUIDANCE...PREFER TO
KEEP JUST LIKELY WORDING IN THE FORECAST (LEARNED UP HERE TO
NEVER...NEVER TRUST CONVECTION). INITIAL SEVERE THREAT SHOULD REMAIN
TO OUR SOUTHWEST MONDAY NIGHT WHERE MORE PRONOUNCED LOW LEVEL
INSTABILITY AXIS AND DEEPER SHEAR ARE BETTER JUXTAPOSED. INCREASING
CONCERN FOR AT LEAST A MINIMAL SEVERE THREAT HEADING INTO TUESDAY
AND WEDNESDAY AS SURFACE WARM FRONT KICKS BACK NORTH...PERHAPS
REACHING AS FAR NORTH AS THE STRAITS BY WEDNESDAY. MUCH TOO EARLY TO
GET TOO SPECIFIC...BUT NORTHWARD SURGING WARM FRONT ITSELF IS
DISCONCERTING...AS IS POTENTIALLY BREAKING INTO THE WARM SECTOR FOR
AT LEAST PARTS OF THE AREA. MUCH...OF COURSE...WILL DEPEND ON
UPSTREAM CONVECTIVE EVOLUTION...BUT WOULD NOT BE AT ALL SURPRISED TO
SEE OUR FIRST SEVERE THUNDERSTORM EVENT OF THE SEASON (AND ENDING
ONE OF THE LATEST STARTS TO SUCH IN OUR RECENT HISTORY). OVERNIGHT
ISSUED SPC SEVERE GRAPHICS CONCUR...BRINGING TUESDAY INTO WEDNESDAY
SLIGHT RISK CATEGORY UP TO ABOUT M-32. DEFINITELY SOMETHING TO
MONITOR IN THE COMING DAYS...BUT WILL DEFER INTRODUCING THIS THREAT
IN THE LATEST RENDITION OF THE HAZARDOUS WEATHER OUTLOOK UNTIL
BETTER CONFIDENCE IS REALIZED. FORECASTING TEMPERATURES EVEN A MUCH
LOWER CONFIDENCE ENDEAVOR THAN ALL THE ABOVE. WILL SIMPLY USE A
CONSENSUS APPROACH FOR NOW...AND WILL HONESTLY STATE FORECAST WILL
LIKELY IN NO WAY MIMIC REALITY.
MID LEVEL LOW OPENS UP AS IT PASSES OVERHEAD LATER WEDNESDAY AND
WEDNESDAY NIGHT (TIMING SUBJECT TO CHANGE...OF COURSE)...EVENTUALLY
BECOMING ABSORBED IN DEEPENING EASTERN TROUGH TO END THE WEEK. RAINS
LOOK TO CONTINUE WEDNESDAY NIGHT...PERHAPS LINGERING INTO THURSDAY.
START OF THE HOLIDAY WEEKEND CONTINUES TO LOOK DRY AND SEASONABLY
COOL AS STRONG CANADIAN HIGH PRESSURE BUILDS SOUTH FRIDAY AND
SATURDAY BETWEEN EASTERN TROUGHING AND HIGH PLAIN RIDGING. HIGHS
TEMPERATURES NOT EXCEPTIONALLY COOL...BUT STILL A FEW DEGREES BELOW
NORMAL...WITH READINGS FRIDAY IN THE UPPER 50S AND LOWER
60S....WARMING SLIGHTLY INTO THE 60S FOR SATURDAY. BIGGER CONCERN
REMAINS FOR SOME RATHER CHILLY OVERNIGHT LOWS. COULD SEE SOME
READINGS DIP INTO THE MIDDLE AND UPPER 30S AS QUICKLY AS THURSDAY
NIGHT...DRIVEN SIMPLY BY SHOT OF CAA ON NORTHEAST TO NORTH WINDS.
PER PATTERN RECOGNITION...FRIDAY NIGHT CONTINUES TO LOOK DOWNRIGHT
CHILLY WITH COOL HIGH PRESSURE AND ATTENDANT DRY AIR CENTERED
DIRECTLY OVERHEAD. DESPITE BEING AT LEAST PARTIALLY CLIMATOLOGICALLY
INFLUENCED AT THIS TIME FRAME...LATEST ECMWF MOS PROGS CONTINUE TO
LOOK RATHER DISCONCERTING...FEATURING WIDESPREAD LOWER AND MIDDLE 30
DEGREE READINGS BY EARLY SATURDAY MORNING (GFS MEX PROGS ALSO
TRENDING COOLER...ALTHOUGH NOT YET TO THIS EXTREME). WILL START THE
PROCESS OF TRENDING COOLER THROUGH THIS PERIOD AND INTRODUCE THE
MENTION OF THIS FROST POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK FOR
NORTHERN LOWER MICHIGAN (FROST/FREEZE SEASON DOESN`T KICK OFF FOR
UPPER MICHIGAN UNTIL MEMORIAL DAY). JUST TOOK A QUICK PERUSAL OF
LATEST 12Z ECMWF...WHICH HAS TRENDED MUCH STRONGER WITH CAA THURSDAY
NIGHT THROUGH SUNDAY. IF THIS IS REALIZED...HIGHS FRIDAY WILL LIKELY
BE STUCK IN THE 50S...WITH OVERNIGHT LOWS RANGING FROM THE MID AND
UPPER 30S THURSDAY NIGHT AND AGAIN SATURDAY NIGHT...WITH WIDESPREAD
UPPER 20 TO MID 30 DEGREE READINGS FRIDAY NIGHT. QUESTIONS ABOUND BY
SUNDAY...WITH SOME POTENTIAL FOR DEVELOPING WAA TO KICK OFF AT LEAST
THE THREAT FOR A FEW SHOWERS. IN NO HURRY TO INTRODUCE THIS JUST YET
GIVEN INHERENT TIMING CONCERNS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1230 PM EDT SUN MAY 19 2013
VFR CONDITIONS WILL CONTINUE AT ALL NRN LWR MICHIGAN TAF SITES
THRU MONDAY MORNING. CHANCES OF SHOWERS AND STORMS WILL INCREASE
LATE TONIGHT INTO MONDAY MORNING AS A FRONT SAGS SOUTH INTO NRN LWR
MICHIGAN AND THE FIRST IN A SERIES OF SHORT WAVES ENTERS MICHIGAN
AHEAD OF LOW PRESSURE DEVELOPING IN THE PLAINS. WILL HANDLE PCPN
DEVELOPMENT WITH VCSH FOR NOW AND BETTER DEFINE TIMING OF PRECIP
AS THE EVENT DRAWS CLOSER. LIGHT SYNOPTIC FLOW WILL ALLOW FOR LAKE
BREEZE DEVELOPMENT THIS AFTERNOON.
&&
.MARINE...
ISSUED AT 340 PM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY THRU TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JK
MARINE...JK
000
FXUS63 KAPX 191701
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
101 PM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 310 AM EDT SUN MAY 19 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE PLAINS...
BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK. THIS
APPROACHING SYSTEM WILL GENERATE SHOWERS AND THUNDERSTORMS ACROSS
NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.UPDATE...
ISSUED AT 1230 PM EDT SUN MAY 19 2013
DIURNAL CU BEGINNING TO BLOSSOM ACROSS INTERIOR SECTIONS AS
TEMPERATURES CLIMB TO NEAR 80 IN SOME LOCATIONS. ALSO SEEING THE
BEGINNINGS OF LAKE BREEZE DEVELOPMENT...WITH ONSHORE FLOW KEEPING
TEMPS IN THE 60S CLOSER TO LAKES MICHIGAN AND HURON. SFC DWPTS
GRADUALLY CLIMBING THROUGH THE 50S...ALTHOUGH NAM MODEL DWPTS
STILL 4-5 DEGF TOO HIGH...CONTINUING R RECENT WET BIAS WITH LOW
LEVEL MOISTURE. FEW CHANGES NEEDED FOR THE AFTERNOON. STILL
ISOLATED SHOWER POSSIBILITY OVER INTERIOR AREAS INVOF INLAND
PENETRATING LAKE BREEZE BOUNDARIES. WILL MAKE A FEW SMALL
ADJUSTMENTS TO TEMPS BASED ON LATEST OBS.
UPDATE ISSUED AT 956 AM EDT SUN MAY 19 2013
FEW CHANGES NEEDED TO ONGOING FORECAST. MID LEVEL RIDGING
GRADUALLY WEAKENING ITS INFLUENCE ON OUR WEATHER WITH SLIGHTLY
BETTER RETURN FLOW DEVELOPING ON THE BACKSIDE. MAIN QUESTION FOR
THE AFTERNOON IS WHETHER WE CAN GET ENOUGH LOW LEVEL MOISTURE TO
GENERATE A FEW POP UP SHOWERS. MODIFYING THE MORNING SOUNDING FROM
APX WITH A HIGH OF 79 AND DEWPOINT OF 55 YIELDS MLCAPE OF ABOUT 350
G/KG. BUT WITH SLIGHT MID LEVEL WARM AIR ADVECTION...DO HAVE
CONCERNS THAT WE MAY BECOME CAPPED IN THE H8-7 LAYER. IF WE CAN
WARM A BIT MORE OR GET DEWPOINTS A LITTLE HIGHER /WHICH IS VERY
QUESTIONABLE GIVEN DOWNSTATE DWPTS/...THAT MAY BE SUFFICIENT TO
SQUEAK BY THIS DEVELOPING MID LEVEL CAP TO GENERATE SOME SKINNY
CAPE. EITHER WAY...CANNOT TOTALLY RULE OUT POP UP SHOWER
DEVELOPMENT THIS AFTERNOON...PARTICULARLY ALONG INLAND PENETRATING
LAKE BREEZE BOUNDARIES. CURRENT 20 POP LOOKS GOOD AND WILL LEAVE
UNCHANGED. OTHERWISE...VERY WARM DAY ACROSS THE AREA WITH HIGHS
RANGING FROM THE MID 70S NORTH TO LOWER 80S SOUTH.
UPDATE ISSUED AT 650 AM EDT SUN MAY 19 2013
A FEW LIGHT SHOWERS CONTINUE TO LINGER ACROSS ERN UPR MICHIGAN
EARLY THIS MORNING. THE REST OF OUR CWA REMAINS DRY AND MAINLY
CLOUDY AS TEMPS HOLD MAINLY IN THE 50S. A FEW SHOWERS MAY DEVELOP
THIS AFTERNOON ACROSS INTERIOR SECTIONS OF NRN LWR MICHIGAN THANKS
TO INCREASING DIURNAL INSTABILITY. OTHERWISE...EXPECT A MAINLY DRY
AND PARTLY SUNNY DAY AS MID CLOUDS CONTINUE TO DRIFT OVERHEAD. LOW
LEVEL SE FLOW WILL ADVECT WARMER TEMPS INTO THE REGION TODAY...
WITH AFTERNOON HIGHS IN THE MID 70S TO LOWER 80S.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 310 AM EDT SUN MAY 19 2013
A GRADUAL STEP UP TOWARD A MUCH MORE ACTIVE PERIOD OF WEATHER BEGINS
TODAY...AS SOME SMALL SHOWER CHANCES ENTER THE FORECAST. THE TIMING
AND EVEN EXISTENCE OF THOSE LATER THIS AFTERNOON REMAINS THE PRIMARY
FORECAST ISSUE THROUGH SUNSET...WITH THE FOCUS SHIFTING TOWARD
POSSIBLE ADDITIONAL PRECIP CHANCES OVERNIGHT. THE EARLY MORNING
WEATHER MAP IS STILL A RATHER QUIET ONE FOR NORTHERN MICHIGAN...AS
EXPANSIVE LOW LEVEL RIDGING REMAINS DRAPED FROM NEWFOUNDLAND DOWN
INTO OUR NECK OF THE WOODS. OF MUCH BIGGER INTEREST IS A RATHER
HEALTHY LONGWAVE TROUGH SLOWLY LIFTING FROM THE SOUTHERN ROCKIES
ONTO THE PLAINS...WITH THIS SYSTEM HELPING DRIVE LEE CYCLOGENESIS
ACROSS WESTERN KANSAS WHILE ALSO KICKING OFF SEVERAL COMPLEXES OF
SHOWERS AND SEVERE STORMS. GRADUAL RAMPING UP OF MID LEVEL WARM
ADVECTION ASCENT WELL AHEAD OF THIS TROUGH CONTINUES TO FORCE AN
AXIS OF THICKER CLOUD COVER UP ACROSS THE U.P...WITH EVEN A FEW
SPITS OF RAIN FALLING AT TIMES...THOUGH HINDERED LARGELY BY A
SIGNIFICANT DRY WEDGE BELOW 750MB.
FOR TODAY...NOT MUCH TO SPEAK OF THIS MORNING WITH RIDGING DOWN LOW
STILL IN CONTROL...THOUGH LOSING ITS INFLUENCE WITH TIME AS THE
RIDGE CORE SLIDES OFF THE NORTHEAST COAST. MEANWHILE...SLIGHTLY
BETTER RETURN FLOW SHOULD GET UNDERWAY...PARTICULARLY THIS AFTERNOON
AS A WARM FRONT TRIES TO MAKE SOME NORTHWARD PROGRESS...ALL WHILE
STRONGER LOW PRESSURE TAKES SHAPE ACROSS SOUTH DAKOTA. THE QUESTION
IS WILL WE GET ENOUGH LOWER LEVEL MOISTURE BACK THIS FAR NORTH TO
AID IN FIRING OFF AT LEAST A FEW AFTERNOON SHOWERS. A FEW THINGS
WORKING IN OUR FAVOR INCLUDE DECENT DAYTIME HEATING EXPECTED...WITH
HIGHS WARMING WELL INTO THE 70S AND LOWER 80S...AND WHAT SHOULD BE
NUMEROUS LOCALIZED TRIGGERS/CONVERGENCE AS LAKE BREEZE DEVELOPMENT
BECOMES WIDESPREAD WITH A LIGHT GRADIENT.
WITH THAT SAID...ARRIVAL OF BUILDING SHORTWAVE RIDGING SQUARELY
OVERHEAD WITH TIME DOES GIVE ONE A LITTLE PAUSE WITH POSSIBLE
CAPPING ISSUES...AND THE FACT THAT GUIDANCE MOISTURE PROGS CAN`T BE
TRUSTED DOESN`T HELP. NAM/GFS DEPICTION OF SURFACE DEW POINTS WELL
INTO THE 60S JUST DOESN`T LOOK DOABLE GIVEN THE TRUE WARM FRONT WILL
LIKELY HOLD TO OUR SOUTH THROUGH THE DAY AS IT BENDS AROUND THE COLD
LAKE WATERS. INSTEAD...LOW OR MID 50S LOOK BETTER...SIMILAR TO
THOSE OBSERVED ACROSS NORTHERN INDIANA YESTERDAY. PER FORECAST
RAOBS...AN 80/55 PARCEL MIGHT JUST BE ABLE TO SQUEAK BY THE
CAP...BUT THAT DOESN`T LEAVE A WHOLE LOT OF AVAILABLE INSTABILITY...
EVEN WITH SOME DECENT (NOT GREAT) LAPSE RATES ARRIVING. THE LONG AND
SHORT OF IT IS THE CHANCE FOR A FEW SHOWERS IS NOT COMPLETELY
ZERO...ESPECIALLY WHERE LAKE BREEZE BOUNDARIES CAN PROVIDE SOME
BETTER MOISTURE POOLING...BUT IT`S CERTAINLY NOTHING HIGHER THAN
ABOUT 20 PERCENT. WILL CONTINUE TO HAVE A MENTION BUT CONFIDENCE IS
NOT VERY HIGH. EASTERN UPPER MIGHT ACTUALLY STAND A BETTER SHOT
WITH THE LEAD INVERTED TROUGH AXIS/WARM FRONT PROVIDING SLIGHTLY
BETTER CONVERGENCE...WHILE THE BACKGROUND/SYNOPTIC FLOW FROM THE
SOUTH TRIES TO PIN ANY SHOWERS CLOSER TO THE LAKE SUPERIOR SHORE.
CHANCES ARE MAYBE A LITTLE BETTER THE FIRST HALF OF TONIGHT AS AN
ELEVATED WARM FRONT LIFTS THROUGH THE REGION ROUGHLY 06-12Z...WITH
THE SURFACE FRONTAL BOUNDARY SLIDING NORTH TOWARD THE STRAITS BY
SUNRISE. LOW LEVEL JET FORCING IS NOTHING SPECTACULAR...NOR IS ANY
UPPER JET OR DYNAMIC FORCING...AS MUCH OF THAT IS RELEGATED WELL TO
OUR WEST IN ADVANCE OF THE STRONGER UPPER TROUGH. STILL...COULD BE
ENOUGH ACCELERATION OF THE LOW LEVEL JET UP THE SPINE OF LAKE
MICHIGAN TO HELP FIRE OFF SOME ADDITIONAL SHOWERS ACROSS MAINLY THE
TIP OF THE MITT AND EASTERN U.P. THROUGH 06Z. AN EVEN BETTER CHANCE
SHOULD ARRIVE FOR THOSE AREAS AND PROBABLY NORTHWEST LOWER TOO AFTER
06Z AS A PRONOUNCED THETA-E RIDGE FOLDS OVER INTO THE AREA...WITH
MUCAPE VALUES ON THE SOUTHERN FRINGE OF THE ELEVATED WARM FRONT
RISING TO AROUND 700 J/KG...SUGGESTING A THUNDER THREAT. A MILD
NIGHT EXPECTED...WITH LOWS ONLY IN THE 50S NORTH TO 60S ACROSS MUCH
OF NORTHERN LOWER...SOUTH OF THE WARM FRONT. IN FACT...COULD SEE A
FEW SPOTS CLOSER TO LAKE MICHIGAN HOLD NOT FAR FROM 70 THROUGH MUCH
OF THE NIGHT...AS IS TYPICAL IN THESE SETUPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT SUN MAY 19 2013
MONDAY THRU WEDNESDAY...PRECIP CHANCES WILL CONTINUE TO INCREASE
FROM WEST TO EAST MONDAY MORNING AS THE WARM FRONT SAGS SOUTHWARD
INTO NRN LWR MICHIGAN. DEVELOPING LOW PRESSURE IN THE PLAINS WILL
BEGIN TO TAP INTO GULF MOISTURE...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. AS
THIS DEEPER MOISTURE BEGINS TO INTERACT WITH THE WARM FRONT AND A
SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING
UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE MONDAY
MORNING...WITH LIKELY POPS EXPECTED THRU WEDNESDAY NIGHT. SURFACE
AND CLOSED UPPER LOW BECOME VERTICALLY STACKED...THUS MAKING VERY
SLOW EASTWARD PROGRESS OVER THIS TIME PERIOD...AND THEREFORE KEEPING
OUR WEATHER UNSETTLED THRU MID WEEK. WARM TEMPS WILL HOLD OVER THE
REGION ON MONDAY BEFORE THE WARM FRONT DROPS SOUTH OF OUR CWA ON
TUESDAY AND WEDNESDAY. HIGH TEMPS ON MONDAY WILL RANGE FROM THE MID
TO UPPER 60S ACROSS ERN UPR MICHIGAN NORTH OF THE WARM FRONT TO THE
MID 70S TO LOWER 80S SOUTH OF THE WARM FRONT. HIGH TEMPS WILL ONLY
REACH INTO THE 60S TO NEAR 70 BOTH TUESDAY AND WEDNESDAY AS THE WARM
FRONT CONTINUES TO DROP SOUTH OF OUR CWA.
WEDNESDAY NIGHT THRU SATURDAY...SURFACE AND UPPER LOW CENTERS WILL
SLOWLY SLIDE THRU LWR MICHIGAN WEDNESDAY NIGHT...EXITING EAST TOWARD
NEW ENGLAND THURSDAY. THE THREAT OF THUNDER WILL END WEDNESDAY NIGHT
AS THE SURFACE LOW CENTER SLIDES JUST SOUTH OF OUR CWA. SOME SHOWERS
WILL LINGER ACROSS OUR CWA WEDNESDAY NIGHT AND THURSDAY...BUT SHOULD
COME TO AN END BY THURSDAY NIGHT AS COLDER AND DRIER AIR FILTER INTO
THE REGION BEHIND THE DEPARTING LOW. CORE OF THE COLD AIR WILL
REMAIN WELL NORTH OF MICHIGAN...BUT LIMITED CAA WILL DROP HIGH TEMPS
INTO THE UPPER 50S AND LOWER 60S FOR BOTH THURSDAY AND FRIDAY. NEXT
WEEKEND STILL LOOKS DRY WITH COOLER THAN NORMAL TEMPS AS THE SURFACE
HIGH AND BROAD UPPER LEVEL TROUGHING BOTH REMAIN LOCKED OVER THE
GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1230 PM EDT SUN MAY 19 2013
VFR CONDITIONS WILL CONTINUE AT ALL NRN LWR MICHIGAN TAF SITES
THRU MONDAY MORNING. CHANCES OF SHOWERS AND STORMS WILL INCREASE
LATE TONIGHT INTO MONDAY MORNING AS A FRONT SAGS SOUTH INTO NRN LWR
MICHIGAN AND THE FIRST IN A SERIES OF SHORT WAVES ENTERS MICHIGAN
AHEAD OF LOW PRESSURE DEVELOPING IN THE PLAINS. WILL HANDLE PCPN
DEVELOPMENT WITH VCSH FOR NOW AND BETTER DEFINE TIMING OF PRECIP
AS THE EVENT DRAWS CLOSER. LIGHT SYNOPTIC FLOW WILL ALLOW FOR LAKE
BREEZE DEVELOPMENT THIS AFTERNOON.
&&
.MARINE...
ISSUED AT 310 AM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY INTO TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JK
SYNOPSIS...MLR
SHORT TERM...LAWRENCE
LONG TERM...MLR
AVIATION...JK
MARINE...LAWRENCE
000
FXUS63 KAPX 191408
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1008 AM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 310 AM EDT SUN MAY 19 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE PLAINS...
BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK. THIS
APPROACHING SYSTEM WILL GENERATE SHOWERS AND THUNDERSTORMS ACROSS
NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.UPDATE...
ISSUED AT 956 AM EDT SUN MAY 19 2013
FEW CHANGES NEEDED TO ONGOING FORECAST. MID LEVEL RIDGING
GRADUALLY WEAKENING ITS INFLUENCE ON OUR WEATHER WITH SLIGHTLY
BETTER RETURN FLOW DEVELOPING ON THE BACKSIDE. MAIN QUESTION FOR
THE AFTERNOON IS WHETHER WE CAN GET ENOUGH LOW LEVEL MOISTURE TO
GENERATE A FEW POP UP SHOWERS. MODIFYING THE MORNING SOUNDING FROM
APX WITH A HIGH OF 79 AND DEWPOINT OF 55 YIELDS MLCAPE OF ABOUT 350
G/KG. BUT WITH SLIGHT MID LEVEL WARM AIR ADVECTION...DO HAVE
CONCERNS THAT WE MAY BECOME CAPPED IN THE H8-7 LAYER. IF WE CAN
WARM A BIT MORE OR GET DEWPOINTS A LITTLE HIGHER /WHICH IS VERY
QUESTIONABLE GIVEN DOWNSTATE DWPTS/...THAT MAY BE SUFFICIENT TO
SQUEAK BY THIS DEVELOPING MID LEVEL CAP TO GENERATE SOME SKINNY
CAPE. EITHER WAY...CANNOT TOTALLY RULE OUT POP UP SHOWER
DEVELOPMENT THIS AFTERNOON...PARTICULARLY ALONG INLAND PENETRATING
LAKE BREEZE BOUNDARIES. CURRENT 20 POP LOOKS GOOD AND WILL LEAVE
UNCHANGED. OTHERWISE...VERY WARM DAY ACROSS THE AREA WITH HIGHS
RANGING FROM THE MID 70S NORTH TO LOWER 80S SOUTH.
UPDATE ISSUED AT 650 AM EDT SUN MAY 19 2013
A FEW LIGHT SHOWERS CONTINUE TO LINGER ACROSS ERN UPR MICHIGAN
EARLY THIS MORNING. THE REST OF OUR CWA REMAINS DRY AND MAINLY
CLOUDY AS TEMPS HOLD MAINLY IN THE 50S. A FEW SHOWERS MAY DEVELOP
THIS AFTERNOON ACROSS INTERIOR SECTIONS OF NRN LWR MICHIGAN THANKS
TO INCREASING DIURNAL INSTABILITY. OTHERWISE...EXPECT A MAINLY DRY
AND PARTLY SUNNY DAY AS MID CLOUDS CONTINUE TO DRIFT OVERHEAD. LOW
LEVEL SE FLOW WILL ADVECT WARMER TEMPS INTO THE REGION TODAY...
WITH AFTERNOON HIGHS IN THE MID 70S TO LOWER 80S.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 310 AM EDT SUN MAY 19 2013
A GRADUAL STEP UP TOWARD A MUCH MORE ACTIVE PERIOD OF WEATHER BEGINS
TODAY...AS SOME SMALL SHOWER CHANCES ENTER THE FORECAST. THE TIMING
AND EVEN EXISTENCE OF THOSE LATER THIS AFTERNOON REMAINS THE PRIMARY
FORECAST ISSUE THROUGH SUNSET...WITH THE FOCUS SHIFTING TOWARD
POSSIBLE ADDITIONAL PRECIP CHANCES OVERNIGHT. THE EARLY MORNING
WEATHER MAP IS STILL A RATHER QUIET ONE FOR NORTHERN MICHIGAN...AS
EXPANSIVE LOW LEVEL RIDGING REMAINS DRAPED FROM NEWFOUNDLAND DOWN
INTO OUR NECK OF THE WOODS. OF MUCH BIGGER INTEREST IS A RATHER
HEALTHY LONGWAVE TROUGH SLOWLY LIFTING FROM THE SOUTHERN ROCKIES
ONTO THE PLAINS...WITH THIS SYSTEM HELPING DRIVE LEE CYCLOGENESIS
ACROSS WESTERN KANSAS WHILE ALSO KICKING OFF SEVERAL COMPLEXES OF
SHOWERS AND SEVERE STORMS. GRADUAL RAMPING UP OF MID LEVEL WARM
ADVECTION ASCENT WELL AHEAD OF THIS TROUGH CONTINUES TO FORCE AN
AXIS OF THICKER CLOUD COVER UP ACROSS THE U.P...WITH EVEN A FEW
SPITS OF RAIN FALLING AT TIMES...THOUGH HINDERED LARGELY BY A
SIGNIFICANT DRY WEDGE BELOW 750MB.
FOR TODAY...NOT MUCH TO SPEAK OF THIS MORNING WITH RIDGING DOWN LOW
STILL IN CONTROL...THOUGH LOSING ITS INFLUENCE WITH TIME AS THE
RIDGE CORE SLIDES OFF THE NORTHEAST COAST. MEANWHILE...SLIGHTLY
BETTER RETURN FLOW SHOULD GET UNDERWAY...PARTICULARLY THIS AFTERNOON
AS A WARM FRONT TRIES TO MAKE SOME NORTHWARD PROGRESS...ALL WHILE
STRONGER LOW PRESSURE TAKES SHAPE ACROSS SOUTH DAKOTA. THE QUESTION
IS WILL WE GET ENOUGH LOWER LEVEL MOISTURE BACK THIS FAR NORTH TO
AID IN FIRING OFF AT LEAST A FEW AFTERNOON SHOWERS. A FEW THINGS
WORKING IN OUR FAVOR INCLUDE DECENT DAYTIME HEATING EXPECTED...WITH
HIGHS WARMING WELL INTO THE 70S AND LOWER 80S...AND WHAT SHOULD BE
NUMEROUS LOCALIZED TRIGGERS/CONVERGENCE AS LAKE BREEZE DEVELOPMENT
BECOMES WIDESPREAD WITH A LIGHT GRADIENT.
WITH THAT SAID...ARRIVAL OF BUILDING SHORTWAVE RIDGING SQUARELY
OVERHEAD WITH TIME DOES GIVE ONE A LITTLE PAUSE WITH POSSIBLE
CAPPING ISSUES...AND THE FACT THAT GUIDANCE MOISTURE PROGS CAN`T BE
TRUSTED DOESN`T HELP. NAM/GFS DEPICTION OF SURFACE DEW POINTS WELL
INTO THE 60S JUST DOESN`T LOOK DOABLE GIVEN THE TRUE WARM FRONT WILL
LIKELY HOLD TO OUR SOUTH THROUGH THE DAY AS IT BENDS AROUND THE COLD
LAKE WATERS. INSTEAD...LOW OR MID 50S LOOK BETTER...SIMILAR TO
THOSE OBSERVED ACROSS NORTHERN INDIANA YESTERDAY. PER FORECAST
RAOBS...AN 80/55 PARCEL MIGHT JUST BE ABLE TO SQUEAK BY THE
CAP...BUT THAT DOESN`T LEAVE A WHOLE LOT OF AVAILABLE INSTABILITY...
EVEN WITH SOME DECENT (NOT GREAT) LAPSE RATES ARRIVING. THE LONG AND
SHORT OF IT IS THE CHANCE FOR A FEW SHOWERS IS NOT COMPLETELY
ZERO...ESPECIALLY WHERE LAKE BREEZE BOUNDARIES CAN PROVIDE SOME
BETTER MOISTURE POOLING...BUT IT`S CERTAINLY NOTHING HIGHER THAN
ABOUT 20 PERCENT. WILL CONTINUE TO HAVE A MENTION BUT CONFIDENCE IS
NOT VERY HIGH. EASTERN UPPER MIGHT ACTUALLY STAND A BETTER SHOT
WITH THE LEAD INVERTED TROUGH AXIS/WARM FRONT PROVIDING SLIGHTLY
BETTER CONVERGENCE...WHILE THE BACKGROUND/SYNOPTIC FLOW FROM THE
SOUTH TRIES TO PIN ANY SHOWERS CLOSER TO THE LAKE SUPERIOR SHORE.
CHANCES ARE MAYBE A LITTLE BETTER THE FIRST HALF OF TONIGHT AS AN
ELEVATED WARM FRONT LIFTS THROUGH THE REGION ROUGHLY 06-12Z...WITH
THE SURFACE FRONTAL BOUNDARY SLIDING NORTH TOWARD THE STRAITS BY
SUNRISE. LOW LEVEL JET FORCING IS NOTHING SPECTACULAR...NOR IS ANY
UPPER JET OR DYNAMIC FORCING...AS MUCH OF THAT IS RELEGATED WELL TO
OUR WEST IN ADVANCE OF THE STRONGER UPPER TROUGH. STILL...COULD BE
ENOUGH ACCELERATION OF THE LOW LEVEL JET UP THE SPINE OF LAKE
MICHIGAN TO HELP FIRE OFF SOME ADDITIONAL SHOWERS ACROSS MAINLY THE
TIP OF THE MITT AND EASTERN U.P. THROUGH 06Z. AN EVEN BETTER CHANCE
SHOULD ARRIVE FOR THOSE AREAS AND PROBABLY NORTHWEST LOWER TOO AFTER
06Z AS A PRONOUNCED THETA-E RIDGE FOLDS OVER INTO THE AREA...WITH
MUCAPE VALUES ON THE SOUTHERN FRINGE OF THE ELEVATED WARM FRONT
RISING TO AROUND 700 J/KG...SUGGESTING A THUNDER THREAT. A MILD
NIGHT EXPECTED...WITH LOWS ONLY IN THE 50S NORTH TO 60S ACROSS MUCH
OF NORTHERN LOWER...SOUTH OF THE WARM FRONT. IN FACT...COULD SEE A
FEW SPOTS CLOSER TO LAKE MICHIGAN HOLD NOT FAR FROM 70 THROUGH MUCH
OF THE NIGHT...AS IS TYPICAL IN THESE SETUPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT SUN MAY 19 2013
MONDAY THRU WEDNESDAY...PRECIP CHANCES WILL CONTINUE TO INCREASE
FROM WEST TO EAST MONDAY MORNING AS THE WARM FRONT SAGS SOUTHWARD
INTO NRN LWR MICHIGAN. DEVELOPING LOW PRESSURE IN THE PLAINS WILL
BEGIN TO TAP INTO GULF MOISTURE...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. AS
THIS DEEPER MOISTURE BEGINS TO INTERACT WITH THE WARM FRONT AND A
SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING
UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE MONDAY
MORNING...WITH LIKELY POPS EXPECTED THRU WEDNESDAY NIGHT. SURFACE
AND CLOSED UPPER LOW BECOME VERTICALLY STACKED...THUS MAKING VERY
SLOW EASTWARD PROGRESS OVER THIS TIME PERIOD...AND THEREFORE KEEPING
OUR WEATHER UNSETTLED THRU MID WEEK. WARM TEMPS WILL HOLD OVER THE
REGION ON MONDAY BEFORE THE WARM FRONT DROPS SOUTH OF OUR CWA ON
TUESDAY AND WEDNESDAY. HIGH TEMPS ON MONDAY WILL RANGE FROM THE MID
TO UPPER 60S ACROSS ERN UPR MICHIGAN NORTH OF THE WARM FRONT TO THE
MID 70S TO LOWER 80S SOUTH OF THE WARM FRONT. HIGH TEMPS WILL ONLY
REACH INTO THE 60S TO NEAR 70 BOTH TUESDAY AND WEDNESDAY AS THE WARM
FRONT CONTINUES TO DROP SOUTH OF OUR CWA.
WEDNESDAY NIGHT THRU SATURDAY...SURFACE AND UPPER LOW CENTERS WILL
SLOWLY SLIDE THRU LWR MICHIGAN WEDNESDAY NIGHT...EXITING EAST TOWARD
NEW ENGLAND THURSDAY. THE THREAT OF THUNDER WILL END WEDNESDAY NIGHT
AS THE SURFACE LOW CENTER SLIDES JUST SOUTH OF OUR CWA. SOME SHOWERS
WILL LINGER ACROSS OUR CWA WEDNESDAY NIGHT AND THURSDAY...BUT SHOULD
COME TO AN END BY THURSDAY NIGHT AS COLDER AND DRIER AIR FILTER INTO
THE REGION BEHIND THE DEPARTING LOW. CORE OF THE COLD AIR WILL
REMAIN WELL NORTH OF MICHIGAN...BUT LIMITED CAA WILL DROP HIGH TEMPS
INTO THE UPPER 50S AND LOWER 60S FOR BOTH THURSDAY AND FRIDAY. NEXT
WEEKEND STILL LOOKS DRY WITH COOLER THAN NORMAL TEMPS AS THE SURFACE
HIGH AND BROAD UPPER LEVEL TROUGHING BOTH REMAIN LOCKED OVER THE
GREAT LAKES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 650 AM EDT SUN MAY 19 2013
VFR CONDITIONS WILL CONTINUE AT ALL NRN LWR MICHIGAN TAF SITES
THRU MONDAY MORNING. CHANCES OF SHOWERS AND STORMS WILL INCREASE
OVERNIGHT AS A WARM FRONT SAGS SOUTH INTO NRN LWR MICHIGAN AND THE
FIRST IN A SERIES OF SHORT WAVES ENTERS MICHIGAN AHEAD OF LOW
PRESSURE DEVELOPING IN THE PLAINS. WILL HANDLE WITH VCSH FOR NOW
AND BETTER DEFINE TIMING OF PRECIP AS THE EVENT DRAWS CLOSER.
LIGHT SYNOPTIC FLOW WILL ALLOW FOR LAKE BREEZE DEVELOPMENT THIS
AFTERNOON.
&&
.MARINE...
ISSUED AT 310 AM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY INTO TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JK
SYNOPSIS...MLR
SHORT TERM...LAWRENCE
LONG TERM...MLR
AVIATION...MR
MARINE...LAWRENCE
000
FXUS63 KAPX 191050
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
650 AM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 310 AM EDT SUN MAY 19 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE PLAINS...
BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK. THIS
APPROACHING SYSTEM WILL GENERATE SHOWERS AND THUNDERSTORMS ACROSS
NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.UPDATE...
ISSUED AT 650 AM EDT SUN MAY 19 2013
A FEW LIGHT SHOWERS CONTINUE TO LINGER ACROSS ERN UPR MICHIGAN
EARLY THIS MORNING. THE REST OF OUR CWA REMAINS DRY AND MAINLY
CLOUDY AS TEMPS HOLD MAINLY IN THE 50S. A FEW SHOWERS MAY DEVELOP
THIS AFTERNOON ACROSS INTERIOR SECTIONS OF NRN LWR MICHIGAN THANKS
TO INCREASING DIURNAL INSTABILITY. OTHERWISE...EXPECT A MAINLY DRY
AND PARTLY SUNNY DAY AS MID CLOUDS CONTINUE TO DRIFT OVERHEAD. LOW
LEVEL SE FLOW WILL ADVECT WARMER TEMPS INTO THE REGION TODAY...
WITH AFTERNOON HIGHS IN THE MID 70S TO LOWER 80S.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 310 AM EDT SUN MAY 19 2013
A GRADUAL STEP UP TOWARD A MUCH MORE ACTIVE PERIOD OF WEATHER BEGINS
TODAY...AS SOME SMALL SHOWER CHANCES ENTER THE FORECAST. THE TIMING
AND EVEN EXISTENCE OF THOSE LATER THIS AFTERNOON REMAINS THE PRIMARY
FORECAST ISSUE THROUGH SUNSET...WITH THE FOCUS SHIFTING TOWARD
POSSIBLE ADDITIONAL PRECIP CHANCES OVERNIGHT. THE EARLY MORNING
WEATHER MAP IS STILL A RATHER QUIET ONE FOR NORTHERN MICHIGAN...AS
EXPANSIVE LOW LEVEL RIDGING REMAINS DRAPED FROM NEWFOUNDLAND DOWN
INTO OUR NECK OF THE WOODS. OF MUCH BIGGER INTEREST IS A RATHER
HEALTHY LONGWAVE TROUGH SLOWLY LIFTING FROM THE SOUTHERN ROCKIES
ONTO THE PLAINS...WITH THIS SYSTEM HELPING DRIVE LEE CYCLOGENESIS
ACROSS WESTERN KANSAS WHILE ALSO KICKING OFF SEVERAL COMPLEXES OF
SHOWERS AND SEVERE STORMS. GRADUAL RAMPING UP OF MID LEVEL WARM
ADVECTION ASCENT WELL AHEAD OF THIS TROUGH CONTINUES TO FORCE AN
AXIS OF THICKER CLOUD COVER UP ACROSS THE U.P...WITH EVEN A FEW
SPITS OF RAIN FALLING AT TIMES...THOUGH HINDERED LARGELY BY A
SIGNIFICANT DRY WEDGE BELOW 750MB.
FOR TODAY...NOT MUCH TO SPEAK OF THIS MORNING WITH RIDGING DOWN LOW
STILL IN CONTROL...THOUGH LOSING ITS INFLUENCE WITH TIME AS THE
RIDGE CORE SLIDES OFF THE NORTHEAST COAST. MEANWHILE...SLIGHTLY
BETTER RETURN FLOW SHOULD GET UNDERWAY...PARTICULARLY THIS AFTERNOON
AS A WARM FRONT TRIES TO MAKE SOME NORTHWARD PROGRESS...ALL WHILE
STRONGER LOW PRESSURE TAKES SHAPE ACROSS SOUTH DAKOTA. THE QUESTION
IS WILL WE GET ENOUGH LOWER LEVEL MOISTURE BACK THIS FAR NORTH TO
AID IN FIRING OFF AT LEAST A FEW AFTERNOON SHOWERS. A FEW THINGS
WORKING IN OUR FAVOR INCLUDE DECENT DAYTIME HEATING EXPECTED...WITH
HIGHS WARMING WELL INTO THE 70S AND LOWER 80S...AND WHAT SHOULD BE
NUMEROUS LOCALIZED TRIGGERS/CONVERGENCE AS LAKE BREEZE DEVELOPMENT
BECOMES WIDESPREAD WITH A LIGHT GRADIENT.
WITH THAT SAID...ARRIVAL OF BUILDING SHORTWAVE RIDGING SQUARELY
OVERHEAD WITH TIME DOES GIVE ONE A LITTLE PAUSE WITH POSSIBLE
CAPPING ISSUES...AND THE FACT THAT GUIDANCE MOISTURE PROGS CAN`T BE
TRUSTED DOESN`T HELP. NAM/GFS DEPICTION OF SURFACE DEW POINTS WELL
INTO THE 60S JUST DOESN`T LOOK DOABLE GIVEN THE TRUE WARM FRONT WILL
LIKELY HOLD TO OUR SOUTH THROUGH THE DAY AS IT BENDS AROUND THE COLD
LAKE WATERS. INSTEAD...LOW OR MID 50S LOOK BETTER...SIMILAR TO
THOSE OBSERVED ACROSS NORTHERN INDIANA YESTERDAY. PER FORECAST
RAOBS...AN 80/55 PARCEL MIGHT JUST BE ABLE TO SQUEAK BY THE
CAP...BUT THAT DOESN`T LEAVE A WHOLE LOT OF AVAILABLE INSTABILITY...
EVEN WITH SOME DECENT (NOT GREAT) LAPSE RATES ARRIVING. THE LONG AND
SHORT OF IT IS THE CHANCE FOR A FEW SHOWERS IS NOT COMPLETELY
ZERO...ESPECIALLY WHERE LAKE BREEZE BOUNDARIES CAN PROVIDE SOME
BETTER MOISTURE POOLING...BUT IT`S CERTAINLY NOTHING HIGHER THAN
ABOUT 20 PERCENT. WILL CONTINUE TO HAVE A MENTION BUT CONFIDENCE IS
NOT VERY HIGH. EASTERN UPPER MIGHT ACTUALLY STAND A BETTER SHOT
WITH THE LEAD INVERTED TROUGH AXIS/WARM FRONT PROVIDING SLIGHTLY
BETTER CONVERGENCE...WHILE THE BACKGROUND/SYNOPTIC FLOW FROM THE
SOUTH TRIES TO PIN ANY SHOWERS CLOSER TO THE LAKE SUPERIOR SHORE.
CHANCES ARE MAYBE A LITTLE BETTER THE FIRST HALF OF TONIGHT AS AN
ELEVATED WARM FRONT LIFTS THROUGH THE REGION ROUGHLY 06-12Z...WITH
THE SURFACE FRONTAL BOUNDARY SLIDING NORTH TOWARD THE STRAITS BY
SUNRISE. LOW LEVEL JET FORCING IS NOTHING SPECTACULAR...NOR IS ANY
UPPER JET OR DYNAMIC FORCING...AS MUCH OF THAT IS RELEGATED WELL TO
OUR WEST IN ADVANCE OF THE STRONGER UPPER TROUGH. STILL...COULD BE
ENOUGH ACCELERATION OF THE LOW LEVEL JET UP THE SPINE OF LAKE
MICHIGAN TO HELP FIRE OFF SOME ADDITIONAL SHOWERS ACROSS MAINLY THE
TIP OF THE MITT AND EASTERN U.P. THROUGH 06Z. AN EVEN BETTER CHANCE
SHOULD ARRIVE FOR THOSE AREAS AND PROBABLY NORTHWEST LOWER TOO AFTER
06Z AS A PRONOUNCED THETA-E RIDGE FOLDS OVER INTO THE AREA...WITH
MUCAPE VALUES ON THE SOUTHERN FRINGE OF THE ELEVATED WARM FRONT
RISING TO AROUND 700 J/KG...SUGGESTING A THUNDER THREAT. A MILD
NIGHT EXPECTED...WITH LOWS ONLY IN THE 50S NORTH TO 60S ACROSS MUCH
OF NORTHERN LOWER...SOUTH OF THE WARM FRONT. IN FACT...COULD SEE A
FEW SPOTS CLOSER TO LAKE MICHIGAN HOLD NOT FAR FROM 70 THROUGH MUCH
OF THE NIGHT...AS IS TYPICAL IN THESE SETUPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT SUN MAY 19 2013
MONDAY THRU WEDNESDAY...PRECIP CHANCES WILL CONTINUE TO INCREASE
FROM WEST TO EAST MONDAY MORNING AS THE WARM FRONT SAGS SOUTHWARD
INTO NRN LWR MICHIGAN. DEVELOPING LOW PRESSURE IN THE PLAINS WILL
BEGIN TO TAP INTO GULF MOISTURE...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. AS
THIS DEEPER MOISTURE BEGINS TO INTERACT WITH THE WARM FRONT AND A
SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING
UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE MONDAY
MORNING...WITH LIKELY POPS EXPECTED THRU WEDNESDAY NIGHT. SURFACE
AND CLOSED UPPER LOW BECOME VERTICALLY STACKED...THUS MAKING VERY
SLOW EASTWARD PROGRESS OVER THIS TIME PERIOD...AND THEREFORE KEEPING
OUR WEATHER UNSETTLED THRU MID WEEK. WARM TEMPS WILL HOLD OVER THE
REGION ON MONDAY BEFORE THE WARM FRONT DROPS SOUTH OF OUR CWA ON
TUESDAY AND WEDNESDAY. HIGH TEMPS ON MONDAY WILL RANGE FROM THE MID
TO UPPER 60S ACROSS ERN UPR MICHIGAN NORTH OF THE WARM FRONT TO THE
MID 70S TO LOWER 80S SOUTH OF THE WARM FRONT. HIGH TEMPS WILL ONLY
REACH INTO THE 60S TO NEAR 70 BOTH TUESDAY AND WEDNESDAY AS THE WARM
FRONT CONTINUES TO DROP SOUTH OF OUR CWA.
WEDNESDAY NIGHT THRU SATURDAY...SURFACE AND UPPER LOW CENTERS WILL
SLOWLY SLIDE THRU LWR MICHIGAN WEDNESDAY NIGHT...EXITING EAST TOWARD
NEW ENGLAND THURSDAY. THE THREAT OF THUNDER WILL END WEDNESDAY NIGHT
AS THE SURFACE LOW CENTER SLIDES JUST SOUTH OF OUR CWA. SOME SHOWERS
WILL LINGER ACROSS OUR CWA WEDNESDAY NIGHT AND THURSDAY...BUT SHOULD
COME TO AN END BY THURSDAY NIGHT AS COLDER AND DRIER AIR FILTER INTO
THE REGION BEHIND THE DEPARTING LOW. CORE OF THE COLD AIR WILL
REMAIN WELL NORTH OF MICHIGAN...BUT LIMITED CAA WILL DROP HIGH TEMPS
INTO THE UPPER 50S AND LOWER 60S FOR BOTH THURSDAY AND FRIDAY. NEXT
WEEKEND STILL LOOKS DRY WITH COOLER THAN NORMAL TEMPS AS THE SURFACE
HIGH AND BROAD UPPER LEVEL TROUGHING BOTH REMAIN LOCKED OVER THE
GREAT LAKES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 650 AM EDT SUN MAY 19 2013
VFR CONDITIONS WILL CONTINUE AT ALL NRN LWR MICHIGAN TAF SITES
THRU MONDAY MORNING. CHANCES OF SHOWERS AND STORMS WILL INCREASE
OVERNIGHT AS A WARM FRONT SAGS SOUTH INTO NRN LWR MICHIGAN AND THE
FIRST IN A SERIES OF SHORT WAVES ENTERS MICHIGAN AHEAD OF LOW
PRESSURE DEVELOPING IN THE PLAINS. WILL HANDLE WITH VCSH FOR NOW
AND BETTER DEFINE TIMING OF PRECIP AS THE EVENT DRAWS CLOSER.
LIGHT SYNOPTIC FLOW WILL ALLOW FOR LAKE BREEZE DEVELOPMENT THIS
AFTERNOON.
&&
.MARINE...
ISSUED AT 310 AM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY INTO TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...MR
SYNOPSIS...MLR
SHORT TERM...LAWRENCE
LONG TERM...MLR
AVIATION...MR
MARINE...LAWRENCE
000
FXUS63 KAPX 190710
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
310 AM EDT SUN MAY 19 2013
.SYNOPSIS...
ISSUED AT 310 AM EDT SUN MAY 19 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE PLAINS...
BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK. THIS
APPROACHING SYSTEM WILL GENERATE SHOWERS AND THUNDERSTORMS ACROSS
NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 310 AM EDT SUN MAY 19 2013
A GRADUAL STEP UP TOWARD A MUCH MORE ACTIVE PERIOD OF WEATHER BEGINS
TODAY...AS SOME SMALL SHOWER CHANCES ENTER THE FORECAST. THE TIMING
AND EVEN EXISTENCE OF THOSE LATER THIS AFTERNOON REMAINS THE PRIMARY
FORECAST ISSUE THROUGH SUNSET...WITH THE FOCUS SHIFTING TOWARD
POSSIBLE ADDITIONAL PRECIP CHANCES OVERNIGHT. THE EARLY MORNING
WEATHER MAP IS STILL A RATHER QUIET ONE FOR NORTHERN MICHIGAN...AS
EXPANSIVE LOW LEVEL RIDGING REMAINS DRAPED FROM NEWFOUNDLAND DOWN
INTO OUR NECK OF THE WOODS. OF MUCH BIGGER INTEREST IS A RATHER
HEALTHY LONGWAVE TROUGH SLOWLY LIFTING FROM THE SOUTHERN ROCKIES
ONTO THE PLAINS...WITH THIS SYSTEM HELPING DRIVE LEE CYCLOGENESIS
ACROSS WESTERN KANSAS WHILE ALSO KICKING OFF SEVERAL COMPLEXES OF
SHOWERS AND SEVERE STORMS. GRADUAL RAMPING UP OF MID LEVEL WARM
ADVECTION ASCENT WELL AHEAD OF THIS TROUGH CONTINUES TO FORCE AN
AXIS OF THICKER CLOUD COVER UP ACROSS THE U.P...WITH EVEN A FEW
SPITS OF RAIN FALLING AT TIMES...THOUGH HINDERED LARGELY BY A
SIGNIFICANT DRY WEDGE BELOW 750MB.
FOR TODAY...NOT MUCH TO SPEAK OF THIS MORNING WITH RIDGING DOWN LOW
STILL IN CONTROL...THOUGH LOSING ITS INFLUENCE WITH TIME AS THE
RIDGE CORE SLIDES OFF THE NORTHEAST COAST. MEANWHILE...SLIGHTLY
BETTER RETURN FLOW SHOULD GET UNDERWAY...PARTICULARLY THIS AFTERNOON
AS A WARM FRONT TRIES TO MAKE SOME NORTHWARD PROGRESS...ALL WHILE
STRONGER LOW PRESSURE TAKES SHAPE ACROSS SOUTH DAKOTA. THE QUESTION
IS WILL WE GET ENOUGH LOWER LEVEL MOISTURE BACK THIS FAR NORTH TO
AID IN FIRING OFF AT LEAST A FEW AFTERNOON SHOWERS. A FEW THINGS
WORKING IN OUR FAVOR INCLUDE DECENT DAYTIME HEATING EXPECTED...WITH
HIGHS WARMING WELL INTO THE 70S AND LOWER 80S...AND WHAT SHOULD BE
NUMEROUS LOCALIZED TRIGGERS/CONVERGENCE AS LAKE BREEZE DEVELOPMENT
BECOMES WIDESPREAD WITH A LIGHT GRADIENT.
WITH THAT SAID...ARRIVAL OF BUILDING SHORTWAVE RIDGING SQUARELY
OVERHEAD WITH TIME DOES GIVE ONE A LITTLE PAUSE WITH POSSIBLE
CAPPING ISSUES...AND THE FACT THAT GUIDANCE MOISTURE PROGS CAN`T BE
TRUSTED DOESN`T HELP. NAM/GFS DEPICTION OF SURFACE DEW POINTS WELL
INTO THE 60S JUST DOESN`T LOOK DOABLE GIVEN THE TRUE WARM FRONT WILL
LIKELY HOLD TO OUR SOUTH THROUGH THE DAY AS IT BENDS AROUND THE COLD
LAKE WATERS. INSTEAD...LOW OR MID 50S LOOK BETTER...SIMILAR TO
THOSE OBSERVED ACROSS NORTHERN INDIANA YESTERDAY. PER FORECAST
RAOBS...AN 80/55 PARCEL MIGHT JUST BE ABLE TO SQUEAK BY THE
CAP...BUT THAT DOESN`T LEAVE A WHOLE LOT OF AVAILABLE INSTABILITY...
EVEN WITH SOME DECENT (NOT GREAT) LAPSE RATES ARRIVING. THE LONG AND
SHORT OF IT IS THE CHANCE FOR A FEW SHOWERS IS NOT COMPLETELY
ZERO...ESPECIALLY WHERE LAKE BREEZE BOUNDARIES CAN PROVIDE SOME
BETTER MOISTURE POOLING...BUT IT`S CERTAINLY NOTHING HIGHER THAN
ABOUT 20 PERCENT. WILL CONTINUE TO HAVE A MENTION BUT CONFIDENCE IS
NOT VERY HIGH. EASTERN UPPER MIGHT ACTUALLY STAND A BETTER SHOT
WITH THE LEAD INVERTED TROUGH AXIS/WARM FRONT PROVIDING SLIGHTLY
BETTER CONVERGENCE...WHILE THE BACKGROUND/SYNOPTIC FLOW FROM THE
SOUTH TRIES TO PIN ANY SHOWERS CLOSER TO THE LAKE SUPERIOR SHORE.
CHANCES ARE MAYBE A LITTLE BETTER THE FIRST HALF OF TONIGHT AS AN
ELEVATED WARM FRONT LIFTS THROUGH THE REGION ROUGHLY 06-12Z...WITH
THE SURFACE FRONTAL BOUNDARY SLIDING NORTH TOWARD THE STRAITS BY
SUNRISE. LOW LEVEL JET FORCING IS NOTHING SPECTACULAR...NOR IS ANY
UPPER JET OR DYNAMIC FORCING...AS MUCH OF THAT IS RELEGATED WELL TO
OUR WEST IN ADVANCE OF THE STRONGER UPPER TROUGH. STILL...COULD BE
ENOUGH ACCELERATION OF THE LOW LEVEL JET UP THE SPINE OF LAKE
MICHIGAN TO HELP FIRE OFF SOME ADDITIONAL SHOWERS ACROSS MAINLY THE
TIP OF THE MITT AND EASTERN U.P. THROUGH 06Z. AN EVEN BETTER CHANCE
SHOULD ARRIVE FOR THOSE AREAS AND PROBABLY NORTHWEST LOWER TOO AFTER
06Z AS A PRONOUNCED THETA-E RIDGE FOLDS OVER INTO THE AREA...WITH
MUCAPE VALUES ON THE SOUTHERN FRINGE OF THE ELEVATED WARM FRONT
RISING TO AROUND 700 J/KG...SUGGESTING A THUNDER THREAT. A MILD
NIGHT EXPECTED...WITH LOWS ONLY IN THE 50S NORTH TO 60S ACROSS MUCH
OF NORTHERN LOWER...SOUTH OF THE WARM FRONT. IN FACT...COULD SEE A
FEW SPOTS CLOSER TO LAKE MICHIGAN HOLD NOT FAR FROM 70 THROUGH MUCH
OF THE NIGHT...AS IS TYPICAL IN THESE SETUPS.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT SUN MAY 19 2013
MONDAY THRU WEDNESDAY...PRECIP CHANCES WILL CONTINUE TO INCREASE
FROM WEST TO EAST MONDAY MORNING AS THE WARM FRONT SAGS SOUTHWARD
INTO NRN LWR MICHIGAN. DEVELOPING LOW PRESSURE IN THE PLAINS WILL
BEGIN TO TAP INTO GULF MOISTURE...ADVECTING IT NORTHWARD THRU THE
LOWER AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. AS
THIS DEEPER MOISTURE BEGINS TO INTERACT WITH THE WARM FRONT AND A
SERIES OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING
UPPER LOWER...SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE MONDAY
MORNING...WITH LIKELY POPS EXPECTED THRU WEDNESDAY NIGHT. SURFACE
AND CLOSED UPPER LOW BECOME VERTICALLY STACKED...THUS MAKING VERY
SLOW EASTWARD PROGRESS OVER THIS TIME PERIOD...AND THEREFORE KEEPING
OUR WEATHER UNSETTLED THRU MID WEEK. WARM TEMPS WILL HOLD OVER THE
REGION ON MONDAY BEFORE THE WARM FRONT DROPS SOUTH OF OUR CWA ON
TUESDAY AND WEDNESDAY. HIGH TEMPS ON MONDAY WILL RANGE FROM THE MID
TO UPPER 60S ACROSS ERN UPR MICHIGAN NORTH OF THE WARM FRONT TO THE
MID 70S TO LOWER 80S SOUTH OF THE WARM FRONT. HIGH TEMPS WILL ONLY
REACH INTO THE 60S TO NEAR 70 BOTH TUESDAY AND WEDNESDAY AS THE WARM
FRONT CONTINUES TO DROP SOUTH OF OUR CWA.
WEDNESDAY NIGHT THRU SATURDAY...SURFACE AND UPPER LOW CENTERS WILL
SLOWLY SLIDE THRU LWR MICHIGAN WEDNESDAY NIGHT...EXITING EAST TOWARD
NEW ENGLAND THURSDAY. THE THREAT OF THUNDER WILL END WEDNESDAY NIGHT
AS THE SURFACE LOW CENTER SLIDES JUST SOUTH OF OUR CWA. SOME SHOWERS
WILL LINGER ACROSS OUR CWA WEDNESDAY NIGHT AND THURSDAY...BUT SHOULD
COME TO AN END BY THURSDAY NIGHT AS COLDER AND DRIER AIR FILTER INTO
THE REGION BEHIND THE DEPARTING LOW. CORE OF THE COLD AIR WILL
REMAIN WELL NORTH OF MICHIGAN...BUT LIMITED CAA WILL DROP HIGH TEMPS
INTO THE UPPER 50S AND LOWER 60S FOR BOTH THURSDAY AND FRIDAY. NEXT
WEEKEND STILL LOOKS DRY WITH COOLER THAN NORMAL TEMPS AS THE SURFACE
HIGH AND BROAD UPPER LEVEL TROUGHING BOTH REMAIN LOCKED OVER THE
GREAT LAKES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1149 PM EDT SAT MAY 18 2013
VFR.
LIGHT SOUTHERLY FLOW IN PLACE IN THE LOW AND MID LEVELS...BETWEEN
HIGH PRESSURE OVER EASTERN CANADA...AND LOW PRESSURE IN THE CENTRAL/
SOUTHERN HIGH PLAINS. THIS WILL SLOWLY BRING MORE LOW-LEVEL MOISTURE
INTO THE REGION. WEAK DISTURBANCE PASSING ACROSS THE REGION
TONIGHT WILL BRING MID CLOUDS TO THE REGION...AND PERHAPS A
SPRINKLE NEAR PLN. ON SUNDAY...A MIX OF CUMULUS AND LINGERING MID
CLOUDS CAN BE EXPECTED. DEVELOPING LAKE BREEZES WILL LIKELY
TRIGGER A FEW SHRA IN THE AFTERNOON...BUT INLAND FROM ALL THE TAF
SITES.
LIGHT WINDS TONIGHT INTO SUNDAY MORNING...WITH ONSHORE WINDS
DEVELOPING EARLY SUNDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 310 AM EDT SUN MAY 19 2013
A WEAK GRADIENT WILL CONTINUE TO PROVIDE LIGHT WINDS ACROSS THE
WATERS TODAY INTO TONIGHT...BUT WITH EASTERLY FLOW GRADUALLY
STRENGTHENING LATE TONIGHT THROUGH MIDWEEK...NORTH OF A WARM FRONT
STALLING NEARBY. SMALL CRAFT ADVISORIES MAY EVENTUALLY BE
NEEDED...ESPECIALLY LATER MONDAY THROUGH WEDNESDAY...AND
PARTICULARLY IN AND AROUND THE STRAITS WHERE EASTERLY FLOW WILL BE
CHANNELED. HIGH PRESSURE IS EXPECTED TO SLOWLY WORK BACK INTO THE
REGION LATE IN THE WORK WEEK AND TOWARD NEXT WEEKEND...WITH A RETURN
TO LIGHT WINDS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...MLR
SHORT TERM...LAWRENCE
LONG TERM...MLR
AVIATION...JZ
MARINE...LAWRENCE
000
FXUS63 KAPX 190349
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1149 PM EDT SAT MAY 18 2013
.SYNOPSIS...
ISSUED AT 316 PM EDT SAT MAY 18 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE
PLAINS...BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK.
THIS APPROACHING SYSTEM WILL GENERATE THUNDERSTORMS AND MILD
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.UPDATE...
ISSUED AT 1013 PM EDT SAT MAY 18 2013
NEWBERRY AND THE SAULTS CONTINUE TO REPORT OCCASIONAL VERY LIGHT
PRECIP. THE RAIN GAGE AT THE SAULT MI ASOS HAS THUS FAR REFUSED TO
CLICK OFF EVEN 0.01 INCH. SO SPRINKLES MAY BE THE BEST
DESCRIPTOR...BUT WITH A CLUSTER OF SOMEWHAT STRONGER RETURNS JUST
WEST OF CHIP/MACK...HAVE MENTIONED SCT -SHRA UP UNTIL 07Z IN
EASTERN UPPER.
MID CLOUDS ARE MAKING A SE-WARD PUSH BACK INTO NORTHERN
LOWER...AND HAVE BECOME MORE WIDESPREAD NORTH OF A TVC-ROGERS
LINE. THE IDEA OF PARTLY CLOUDY SOUTH AND MOSTLY CLOUDY NORTH
STILL LOOKS SOUND...WITH SOME POTENTIAL FOR BUBBLY CU DEBRIS
DOWNSTATE TO BE DRAWN NORTHWARD INTO SOUTHERN SECTIONS OVERNIGHT.
ONLY MINOR TWEAKS TO MIN TEMPS.
UPDATE ISSUED AT 728 PM EDT SAT MAY 18 2013
VERY SPOTTY SPRINKLES/-SHRA RESTRICTED TO EASTERN UPPER MI (MAINLY
CHIPPEWA CO). TWIN SAULTS BOTH REPORTING OFF-AND-ON RAIN IN THE
PAST COUPLE OF HOURS. CLOUD COVER HAS DIMINISHED CONSIDERABLY IN
NORTHERN LOWER MI...WITH SOME PARTIAL CLEARING AS FAR NORTH AS WESTERN
MACKINAC. PRECIP FORECAST SEEMS TO BE IN GOOD SHAPE...WILL
CONTINUE TO BABYSIT CLOUD TRENDS AND ADJUST AS NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
ELEVATED WARM FRONT/WARM AIR ADVECTION WING CONTINUES TO LIFT THRU
THE AREA TONIGHT WITH LINGERING MID LEVEL FGEN AND ADIABATIC OMEGA
POSSIBLY PRODUCING A FEW SPRINKLES/LIGHT SHOWER TIP OF THE MITT INTO
EASTERN UPPER. SKY CONDITIONS RANGING FROM PARTLY CLOUDY SOUTH TO
MOSTLY CLOUDY NORTH. A MILD NIGHT WITH LOWS FROM THE MID 40S TO
LOWER 50S.
BY FAR THE BEST DAY OF THE WEEKEND ON SUNDAY WITH 850MB THERMAL
RIDGE OF 13-15C BUILDING INTO THE AREA. MID LEVEL RIDGING WILL
CONTINUE TO DOMINATE OUR WEATHER PICTURE AS DEEPER TROUGH DIGS INTO
THE NORTHERN PLAINS. SFC DEWPOINTS WILL CONTINUE TO GRADUALLY CREEP
UP AS THE DAY PROGRESSES. NAM CONTINUING ITS RECENT BIAS OF TOO WET
LOWER LEVELS...WITH CURRENT FCST DEWPOINTS 3-5 DEGF TOO HIGH BASED
ON LATEST OBSERVATIONS. QUITE WARM ON SUNDAY...WITH HIGH TEMPS
REACHING THE MIDDLE 70S /EASTERN UPPER/ TO LOWER 80S /PORTIONS OF
NORTHERN LOWER/. WEAK GRADIENT AND WARM TEMPS LEND ITSELF TO LAKE
BREEZE DEVELOPMENT DURING THE AFTERNOON HOURS AND WILL COOL TEMPS
CLOSER TO THE COASTS TO ACCOUNT FOR THIS. EVEN WITH SLIGHTLY LOWER
DWPTS THAN THE NAM FCST SOUNDINGS...MODIFIED SOUNDINGS WITH NEAR DRY
ADIABATIC MIXED LAYER YIELD SEVERAL HUNDRED JOULES OF SKINNY CAPE.
INLAND PENETRATING LAKE BREEZE BOUNDARIES...INCREASING SFC DWPTS AND
SOME INSTABILITY SUPPORT ISOLATED SHOWER MENTION FOR INTERIOR AREAS
DURING THE MID/LATE AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
MID AND UPPER LEVEL PATTERN BECOMING INCREASINGLY BLOCKY WITH
TIME...AT LEAST PARTIALLY DRIVEN BY STRONG NORTH CENTRAL ATLANTIC
CENTERED HIGH PRESSURE RIDGE AXIS. DUAL STRONG SHORTWAVE TROUGHS
DIVING INTO THE PACIFIC NORTHWEST ONLY HELPING THE CAUSE...WITH LEAD
ENERGY EVENTUALLY CARVING OUT A SLOW MOVING UPPER LOW IN THE NATIONS
MIDSECTION EARLY NEXT WORK WEEK...WHILE THE NEXT PIECE DOES THE SAME
ACROSS THE PACIFIC NORTHWEST. SUBSEQUENT CANADIAN PRAIRIE RIDGE
BUILDING BETWEEN THESE FEATURES SETS UP A QUASI-OMEGA BLOCK
SIGNATURE...WITH STRONG ENERGY PROGGED TO DIVE DOWN ITS FRONTSIDE
INTO EAST CENTRAL CANADA ONLY ADDING FURTHER COMPLEXITY TO AN
ALREADY COMPLEX PATTERN. ADD IN A GOOD SUPPLY OF GULF OF MEXICO
MOISTURE AND FGEN DYNAMICS...AND THE PATTERN HAS ALL THE MAKINGS OF
A WET ONE THROUGH AT LEAST THE FIRST HALF OF THIS UPCOMING WEEK.
LATEST WPC 5 AND 7 DAY QUANTITATIVE PRECIPITATION FORECASTS
CONCUR...WITH WIDESPREAD 1 TO 2 INCH AMOUNTS ACROSS OUR AREA...WITH
HEAVIER AMOUNTS TO UPWARDS OF 4 INCHES JUST TO OUR NORTHWEST. AS ONE
CAN IMAGINE GIVEN ABOVE...EXTENDED FORECAST CONCERNS MAINLY CENTER
ON MULTI-PERIOD RAIN SHOWER AND THUNDERSTORM THREATS.
ONE COMPLICATED FORECAST SUNDAY NIGHT INTO MONDAY...WHICH...TO BE
HONEST...DOES NOT SUPPORT A WHOLE LOT OF FORECAST CONFIDENCE.
CENTRAL PLAINS CLOSED LOW BECOMES INCREASINGLY WELL ESTABLISHED...
WITH EXCELLENT FORCED LOW/MID LEVEL CONVERGENCE ZONE SETTING UP
BETWEEN SOUTH FLOW OUT AHEAD OF IT WEAK ENERGY DIVING THROUGH
ONTARIO. STRONG H8 CONVERGENCE AXIS LOOKS TO SLOWLY SAG SOUTH ACROSS
LAKE SUPERIOR SUNDAY NIGHT INTO MONDAY...WITH SURFACE REFLECTION
ESSENTIALLY REMAINING STATIONARY ACROSS THE CLIMATOLOGICALLY FAVORED
TIP OF THE MITT/STRAITS REGION. H8 FRONT LOOKS TO REMAIN VERY
ACTIVE...FOCUSING MUCH OF THE RAIN OFF TO OUR NORTH THROUGH SUNDAY
NIGHT...PERHAPS INTO THE FIRST PART OF MONDAY (HELPED IN PART BY MID
LEVEL RIDGING REMAINING OVERHEAD). CONDITIONS BECOME MUCH MORE
INTERESTING HEADING INTO MONDAY AFTERNOON AND NIGHT AS ENERGY
ROTATING AROUND UPPER LEVEL LOW INTERACTS WITH AN INCREASINGLY
IMPRESSIVE OVERHEAD MOISTURE PLUME AS PWAT VALUES APPROACH AN INCH
AND A HALF. WHILE MODEL DEPICTED SURFACE DEWPOINTS IN THE UPPER
60S/LOWER 70S SEEM AGGRESSIVE...JUXTAPOSITION OF DECENT MOISTURE AND
MID LEVEL SUPPORT SHOULD BE ENOUGH TO KICK OFF ROUNDS OF SHOWERS AND
STORMS...SOME OF WHICH MAY BRING LOCALLY HEAVY RAINFALL. WHILE
SEVERE THREAT NOT COMPLETELY ZERO...BETTER POTENTIAL SHOULD REMAIN
TO OUR SOUTHWEST WITHIN CORRIDOR OF MUCH MORE IMPRESSIVE DEEP LAYER
SHEAR AND BETTER LOW LEVEL INSTABILITY. LATEST DAY 3 SPC SEVERE
GRAPHICS DOES BRING THE SLIGHT RISK RIGHT TO OUR DOORSTEP OVER
SOUTHWEST MICHIGAN. NO DOUBT WORTH KEEPING AN EYE ON THE NEXT FEW
DAYS AS UPSTREAM CONVECTIVE TRENDS WILL LIKELY PLAY HAVOC WITH EXACT
THERMODYNAMIC AND KINEMATIC DETAILS. POTENTIALLY ANOTHER WARM ONE
MONDAY...ESPECIALLY SOUTH OF THE BRIDGE. THERMAL PROGS EASILY
SUPPORT HIGHS BACK INTO THE LOWER 80S...ALTHOUGH CLOUD AND
CONVECTIVE TRENDS MAY PREVENT FULL WARMING FROM BEING REALIZED.
MID-WEEK WEATHER DEPENDENT ON INTERACTION (OR LACK THEREOF) BETWEEN
APPROACHING MID LEVEL LOW AND STRONGER ENERGY DIVING SOUTH OUT OF
CANADA. THE FORMER CONTINUES TO SUPPLY PLENTY OF MOISTURE AND
DYNAMICS...WHILE THE LATTER ATTEMPTS TO DRIVE BEST FGEN/BAROCLINIC
ZONE FURTHER SOUTH WITH TIME. DEEP LAYER CONVERGENCE AND MOISTURE
SUPPORTS PLENTY OF RAIN POTENTIAL...WITH PLACEMENT OF THE HEAVIEST
AND STEADIEST RAINFALL TIED TO ABOVE INTERACTION. 00Z ECMWF/GEM
OFFER A RATHER WET SCENARIO...KEEPING CORRIDOR OF DEEP LAYER
CONVERGENCE OVERHEAD RIGHT THROUGH THURSDAY. GFS A TOUCH MORE
AGGRESSIVE DRIVING THIS CORRIDOR SOUTH...ALTHOUGH IT TOO SUGGESTS
LINGERING RAINS INTO THURSDAY (JUST NOT AS HEAVY). HARD TO GET A
FEEL FOR WHICH IS MORE CORRECT...WITH THE END RESULT LIKELY A MIDDLE
GROUND BETWEEN THE TWO. INHERITED FORECAST KEEPS RAINS LINGERING
THROUGH THURSDAY...AS WILL THIS FORECAST. SEVERE THREAT SHOULD ONLY
SAG SOUTH WITH TIME AS LOW LEVEL BAROCLINIC ZONE DOES THE SAME. THAT
SAID...PROXIMITY OF IT AND SOME EVIDENCE FOR IT TO RETURN BRIEFLY
NORTH LATER WEDNESDAY...AS MAIN WESTERN ENERGY APPROACHES...
DEFINITELY RAISES SOME CONCERN.
START OF MEMORIAL DAY WEEKEND LOOKING COOL AND DRY AS CANADIAN HIGH
PRESSURE BUILDS OVERHEAD. HIGHS FRIDAY AND SATURDAY LOOK TO ONLY
REACH INTO 60S (UPPER 50S ACROSS EASTERN UPPER?)...WHICH WOULD BE AT
LEAST A FEW DEGREES BELOW NORMAL. PATTERN RECOGNITION SUPPORTS THE
POTENTIAL FOR SOME RATHER CHILLY OVERNIGHT READINGS THURSDAY THROUGH
SATURDAY. SOMEWHAT DISCONCERTING TO SEE LATEST CLIMO INFLUENCED
ECMWF MOS SHOWING COLDER LOCATIONS DIPPING INTO THE MIDDLE AND UPPER
30S EARLY FRIDAY MORNING...AND WIDESPREAD LOWER AND MIDDLE 30 DEGREE
READINGS SATURDAY MORNING. OTHER GUIDANCE NOT QUITE AS COLD...BUT
DEFINITELY SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1149 PM EDT SAT MAY 18 2013
VFR.
LIGHT SOUTHERLY FLOW IN PLACE IN THE LOW AND MID LEVELS...BETWEEN
HIGH PRESSURE OVER EASTERN CANADA...AND LOW PRESSURE IN THE CENTRAL/
SOUTHERN HIGH PLAINS. THIS WILL SLOWLY BRING MORE LOW-LEVEL MOISTURE
INTO THE REGION. WEAK DISTURBANCE PASSING ACROSS THE REGION
TONIGHT WILL BRING MID CLOUDS TO THE REGION...AND PERHAPS A
SPRINKLE NEAR PLN. ON SUNDAY...A MIX OF CUMULUS AND LINGERING MID
CLOUDS CAN BE EXPECTED. DEVELOPING LAKE BREEZES WILL LIKELY
TRIGGER A FEW SHRA IN THE AFTERNOON...BUT INLAND FROM ALL THE TAF
SITES.
LIGHT WINDS TONIGHT INTO SUNDAY MORNING...WITH ONSHORE WINDS
DEVELOPING EARLY SUNDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 316 PM EDT SAT MAY 18 2013
GRADIENT WILL REMAIN RELATIVELY WEAK OVER THE NEXT FEW DAYS AS HIGH
PRESSURE SLOWLY DEPARTS TO THE EAST. AS LOW PRESSURE DRAWS CLOSER
TO THE AREA TUESDAY/WEDNESDAY...WINDS WILL INCREASE AND SMALL
CRAFT CONDITIONS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JZ
MARINE...JK
000
FXUS63 KAPX 190213
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1013 PM EDT SAT MAY 18 2013
.SYNOPSIS...
ISSUED AT 316 PM EDT SAT MAY 18 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE
PLAINS...BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK.
THIS APPROACHING SYSTEM WILL GENERATE THUNDERSTORMS AND MILD
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.UPDATE...
ISSUED AT 1013 PM EDT SAT MAY 18 2013
NEWBERRY AND THE SAULTS CONTINUE TO REPORT OCCASIONAL VERY LIGHT
PRECIP. THE RAIN GAGE AT THE SAULT MI ASOS HAS THUS FAR REFUSED TO
CLICK OFF EVEN 0.01 INCH. SO SPRINKLES MAY BE THE BEST
DESCRIPTOR...BUT WITH A CLUSTER OF SOMEWHAT STRONGER RETURNS JUST
WEST OF CHIP/MACK...HAVE MENTIONED SCT -SHRA UP UNTIL 07Z IN
EASTERN UPPER.
MID CLOUDS ARE MAKING A SE-WARD PUSH BACK INTO NORTHERN
LOWER...AND HAVE BECOME MORE WIDESPREAD NORTH OF A TVC-ROGERS
LINE. THE IDEA OF PARTLY CLOUDY SOUTH AND MOSTLY CLOUDY NORTH
STILL LOOKS SOUND...WITH SOME POTENTIAL FOR BUBBLY CU DEBRIS
DOWNSTATE TO BE DRAWN NORTHWARD INTO SOUTHERN SECTIONS OVERNIGHT.
ONLY MINOR TWEAKS TO MIN TEMPS.
UPDATE ISSUED AT 728 PM EDT SAT MAY 18 2013
VERY SPOTTY SPRINKLES/-SHRA RESTRICTED TO EASTERN UPPER MI (MAINLY
CHIPPEWA CO). TWIN SAULTS BOTH REPORTING OFF-AND-ON RAIN IN THE
PAST COUPLE OF HOURS. CLOUD COVER HAS DIMINISHED CONSIDERABLY IN
NORTHERN LOWER MI...WITH SOME PARTIAL CLEARING AS FAR NORTH AS WESTERN
MACKINAC. PRECIP FORECAST SEEMS TO BE IN GOOD SHAPE...WILL
CONTINUE TO BABYSIT CLOUD TRENDS AND ADJUST AS NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
ELEVATED WARM FRONT/WARM AIR ADVECTION WING CONTINUES TO LIFT THRU
THE AREA TONIGHT WITH LINGERING MID LEVEL FGEN AND ADIABATIC OMEGA
POSSIBLY PRODUCING A FEW SPRINKLES/LIGHT SHOWER TIP OF THE MITT INTO
EASTERN UPPER. SKY CONDITIONS RANGING FROM PARTLY CLOUDY SOUTH TO
MOSTLY CLOUDY NORTH. A MILD NIGHT WITH LOWS FROM THE MID 40S TO
LOWER 50S.
BY FAR THE BEST DAY OF THE WEEKEND ON SUNDAY WITH 850MB THERMAL
RIDGE OF 13-15C BUILDING INTO THE AREA. MID LEVEL RIDGING WILL
CONTINUE TO DOMINATE OUR WEATHER PICTURE AS DEEPER TROUGH DIGS INTO
THE NORTHERN PLAINS. SFC DEWPOINTS WILL CONTINUE TO GRADUALLY CREEP
UP AS THE DAY PROGRESSES. NAM CONTINUING ITS RECENT BIAS OF TOO WET
LOWER LEVELS...WITH CURRENT FCST DEWPOINTS 3-5 DEGF TOO HIGH BASED
ON LATEST OBSERVATIONS. QUITE WARM ON SUNDAY...WITH HIGH TEMPS
REACHING THE MIDDLE 70S /EASTERN UPPER/ TO LOWER 80S /PORTIONS OF
NORTHERN LOWER/. WEAK GRADIENT AND WARM TEMPS LEND ITSELF TO LAKE
BREEZE DEVELOPMENT DURING THE AFTERNOON HOURS AND WILL COOL TEMPS
CLOSER TO THE COASTS TO ACCOUNT FOR THIS. EVEN WITH SLIGHTLY LOWER
DWPTS THAN THE NAM FCST SOUNDINGS...MODIFIED SOUNDINGS WITH NEAR DRY
ADIABATIC MIXED LAYER YIELD SEVERAL HUNDRED JOULES OF SKINNY CAPE.
INLAND PENETRATING LAKE BREEZE BOUNDARIES...INCREASING SFC DWPTS AND
SOME INSTABILITY SUPPORT ISOLATED SHOWER MENTION FOR INTERIOR AREAS
DURING THE MID/LATE AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
MID AND UPPER LEVEL PATTERN BECOMING INCREASINGLY BLOCKY WITH
TIME...AT LEAST PARTIALLY DRIVEN BY STRONG NORTH CENTRAL ATLANTIC
CENTERED HIGH PRESSURE RIDGE AXIS. DUAL STRONG SHORTWAVE TROUGHS
DIVING INTO THE PACIFIC NORTHWEST ONLY HELPING THE CAUSE...WITH LEAD
ENERGY EVENTUALLY CARVING OUT A SLOW MOVING UPPER LOW IN THE NATIONS
MIDSECTION EARLY NEXT WORK WEEK...WHILE THE NEXT PIECE DOES THE SAME
ACROSS THE PACIFIC NORTHWEST. SUBSEQUENT CANADIAN PRAIRIE RIDGE
BUILDING BETWEEN THESE FEATURES SETS UP A QUASI-OMEGA BLOCK
SIGNATURE...WITH STRONG ENERGY PROGGED TO DIVE DOWN ITS FRONTSIDE
INTO EAST CENTRAL CANADA ONLY ADDING FURTHER COMPLEXITY TO AN
ALREADY COMPLEX PATTERN. ADD IN A GOOD SUPPLY OF GULF OF MEXICO
MOISTURE AND FGEN DYNAMICS...AND THE PATTERN HAS ALL THE MAKINGS OF
A WET ONE THROUGH AT LEAST THE FIRST HALF OF THIS UPCOMING WEEK.
LATEST WPC 5 AND 7 DAY QUANTITATIVE PRECIPITATION FORECASTS
CONCUR...WITH WIDESPREAD 1 TO 2 INCH AMOUNTS ACROSS OUR AREA...WITH
HEAVIER AMOUNTS TO UPWARDS OF 4 INCHES JUST TO OUR NORTHWEST. AS ONE
CAN IMAGINE GIVEN ABOVE...EXTENDED FORECAST CONCERNS MAINLY CENTER
ON MULTI-PERIOD RAIN SHOWER AND THUNDERSTORM THREATS.
ONE COMPLICATED FORECAST SUNDAY NIGHT INTO MONDAY...WHICH...TO BE
HONEST...DOES NOT SUPPORT A WHOLE LOT OF FORECAST CONFIDENCE.
CENTRAL PLAINS CLOSED LOW BECOMES INCREASINGLY WELL ESTABLISHED...
WITH EXCELLENT FORCED LOW/MID LEVEL CONVERGENCE ZONE SETTING UP
BETWEEN SOUTH FLOW OUT AHEAD OF IT WEAK ENERGY DIVING THROUGH
ONTARIO. STRONG H8 CONVERGENCE AXIS LOOKS TO SLOWLY SAG SOUTH ACROSS
LAKE SUPERIOR SUNDAY NIGHT INTO MONDAY...WITH SURFACE REFLECTION
ESSENTIALLY REMAINING STATIONARY ACROSS THE CLIMATOLOGICALLY FAVORED
TIP OF THE MITT/STRAITS REGION. H8 FRONT LOOKS TO REMAIN VERY
ACTIVE...FOCUSING MUCH OF THE RAIN OFF TO OUR NORTH THROUGH SUNDAY
NIGHT...PERHAPS INTO THE FIRST PART OF MONDAY (HELPED IN PART BY MID
LEVEL RIDGING REMAINING OVERHEAD). CONDITIONS BECOME MUCH MORE
INTERESTING HEADING INTO MONDAY AFTERNOON AND NIGHT AS ENERGY
ROTATING AROUND UPPER LEVEL LOW INTERACTS WITH AN INCREASINGLY
IMPRESSIVE OVERHEAD MOISTURE PLUME AS PWAT VALUES APPROACH AN INCH
AND A HALF. WHILE MODEL DEPICTED SURFACE DEWPOINTS IN THE UPPER
60S/LOWER 70S SEEM AGGRESSIVE...JUXTAPOSITION OF DECENT MOISTURE AND
MID LEVEL SUPPORT SHOULD BE ENOUGH TO KICK OFF ROUNDS OF SHOWERS AND
STORMS...SOME OF WHICH MAY BRING LOCALLY HEAVY RAINFALL. WHILE
SEVERE THREAT NOT COMPLETELY ZERO...BETTER POTENTIAL SHOULD REMAIN
TO OUR SOUTHWEST WITHIN CORRIDOR OF MUCH MORE IMPRESSIVE DEEP LAYER
SHEAR AND BETTER LOW LEVEL INSTABILITY. LATEST DAY 3 SPC SEVERE
GRAPHICS DOES BRING THE SLIGHT RISK RIGHT TO OUR DOORSTEP OVER
SOUTHWEST MICHIGAN. NO DOUBT WORTH KEEPING AN EYE ON THE NEXT FEW
DAYS AS UPSTREAM CONVECTIVE TRENDS WILL LIKELY PLAY HAVOC WITH EXACT
THERMODYNAMIC AND KINEMATIC DETAILS. POTENTIALLY ANOTHER WARM ONE
MONDAY...ESPECIALLY SOUTH OF THE BRIDGE. THERMAL PROGS EASILY
SUPPORT HIGHS BACK INTO THE LOWER 80S...ALTHOUGH CLOUD AND
CONVECTIVE TRENDS MAY PREVENT FULL WARMING FROM BEING REALIZED.
MID-WEEK WEATHER DEPENDENT ON INTERACTION (OR LACK THEREOF) BETWEEN
APPROACHING MID LEVEL LOW AND STRONGER ENERGY DIVING SOUTH OUT OF
CANADA. THE FORMER CONTINUES TO SUPPLY PLENTY OF MOISTURE AND
DYNAMICS...WHILE THE LATTER ATTEMPTS TO DRIVE BEST FGEN/BAROCLINIC
ZONE FURTHER SOUTH WITH TIME. DEEP LAYER CONVERGENCE AND MOISTURE
SUPPORTS PLENTY OF RAIN POTENTIAL...WITH PLACEMENT OF THE HEAVIEST
AND STEADIEST RAINFALL TIED TO ABOVE INTERACTION. 00Z ECMWF/GEM
OFFER A RATHER WET SCENARIO...KEEPING CORRIDOR OF DEEP LAYER
CONVERGENCE OVERHEAD RIGHT THROUGH THURSDAY. GFS A TOUCH MORE
AGGRESSIVE DRIVING THIS CORRIDOR SOUTH...ALTHOUGH IT TOO SUGGESTS
LINGERING RAINS INTO THURSDAY (JUST NOT AS HEAVY). HARD TO GET A
FEEL FOR WHICH IS MORE CORRECT...WITH THE END RESULT LIKELY A MIDDLE
GROUND BETWEEN THE TWO. INHERITED FORECAST KEEPS RAINS LINGERING
THROUGH THURSDAY...AS WILL THIS FORECAST. SEVERE THREAT SHOULD ONLY
SAG SOUTH WITH TIME AS LOW LEVEL BAROCLINIC ZONE DOES THE SAME. THAT
SAID...PROXIMITY OF IT AND SOME EVIDENCE FOR IT TO RETURN BRIEFLY
NORTH LATER WEDNESDAY...AS MAIN WESTERN ENERGY APPROACHES...
DEFINITELY RAISES SOME CONCERN.
START OF MEMORIAL DAY WEEKEND LOOKING COOL AND DRY AS CANADIAN HIGH
PRESSURE BUILDS OVERHEAD. HIGHS FRIDAY AND SATURDAY LOOK TO ONLY
REACH INTO 60S (UPPER 50S ACROSS EASTERN UPPER?)...WHICH WOULD BE AT
LEAST A FEW DEGREES BELOW NORMAL. PATTERN RECOGNITION SUPPORTS THE
POTENTIAL FOR SOME RATHER CHILLY OVERNIGHT READINGS THURSDAY THROUGH
SATURDAY. SOMEWHAT DISCONCERTING TO SEE LATEST CLIMO INFLUENCED
ECMWF MOS SHOWING COLDER LOCATIONS DIPPING INTO THE MIDDLE AND UPPER
30S EARLY FRIDAY MORNING...AND WIDESPREAD LOWER AND MIDDLE 30 DEGREE
READINGS SATURDAY MORNING. OTHER GUIDANCE NOT QUITE AS COLD...BUT
DEFINITELY SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 728 PM EDT SAT MAY 18 2013
VFR.
LIGHT SOUTHERLY FLOW IN PLACE IN THE LOW AND MID LEVELS...BETWEEN
HIGH PRESSURE OVER EASTERN CANADA...AND LOW PRESSURE IN THE CENTRAL/
SOUTHERN HIGH PLAINS. THIS WILL SLOWLY BRING MORE LOW-LEVEL MOISTURE
INTO THE REGION. INITIALLY...BAND OF MID/HIGH CLOUDS WILL CONTINUE
TO LIFT NORTH OUT OF NORTHERN LOWER TONIGHT. PATCHY MID CLOUDS
WILL RETURN TO NORTHERN LOWER OVERNIGHT FROM THE SOUTH. SUNDAY
WILL BE SUNNIER...WARMER...AND SOMEWHAT MORE HUMID. DEVELOPING LAKE
BREEZES WILL LIKELY TRIGGER A FEW SHRA IN THE AFTERNOON...BUT
INLAND FROM ALL THE TAF SITES.
LIGHT WINDS TONIGHT INTO SUNDAY MORNING...WITH ONSHORE WINDS
DEVELOPING EARLY SUNDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 316 PM EDT SAT MAY 18 2013
GRADIENT WILL REMAIN RELATIVELY WEAK OVER THE NEXT FEW DAYS AS HIGH
PRESSURE SLOWLY DEPARTS TO THE EAST. AS LOW PRESSURE DRAWS CLOSER
TO THE AREA TUESDAY/WEDNESDAY...WINDS WILL INCREASE AND SMALL
CRAFT CONDITIONS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JZ
MARINE...JK
000
FXUS63 KAPX 182328
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
728 PM EDT SAT MAY 18 2013
.SYNOPSIS...
ISSUED AT 316 PM EDT SAT MAY 18 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE
PLAINS...BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK.
THIS APPROACHING SYSTEM WILL GENERATE THUNDERSTORMS AND MILD
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.UPDATE...
ISSUED AT 728 PM EDT SAT MAY 18 2013
VERY SPOTTY SPRINKLES/-SHRA RESTRICTED TO EASTERN UPPER MI (MAINLY
CHIPPEWA CO). TWIN SAULTS BOTH REPORTING OFF-AND-ON RAIN IN THE
PAST COUPLE OF HOURS. CLOUD COVER HAS DIMINISHED CONSIDERABLY IN
NORTHERN LOWER MI...WITH SOME PARTIAL CLEARING AS FAR NORTH AS WESTERN
MACKINAC. PRECIP FORECAST SEEMS TO BE IN GOOD SHAPE...WILL
CONTINUE TO BABYSIT CLOUD TRENDS AND ADJUST AS NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
ELEVATED WARM FRONT/WARM AIR ADVECTION WING CONTINUES TO LIFT THRU
THE AREA TONIGHT WITH LINGERING MID LEVEL FGEN AND ADIABATIC OMEGA
POSSIBLY PRODUCING A FEW SPRINKLES/LIGHT SHOWER TIP OF THE MITT INTO
EASTERN UPPER. SKY CONDITIONS RANGING FROM PARTLY CLOUDY SOUTH TO
MOSTLY CLOUDY NORTH. A MILD NIGHT WITH LOWS FROM THE MID 40S TO
LOWER 50S.
BY FAR THE BEST DAY OF THE WEEKEND ON SUNDAY WITH 850MB THERMAL
RIDGE OF 13-15C BUILDING INTO THE AREA. MID LEVEL RIDGING WILL
CONTINUE TO DOMINATE OUR WEATHER PICTURE AS DEEPER TROUGH DIGS INTO
THE NORTHERN PLAINS. SFC DEWPOINTS WILL CONTINUE TO GRADUALLY CREEP
UP AS THE DAY PROGRESSES. NAM CONTINUING ITS RECENT BIAS OF TOO WET
LOWER LEVELS...WITH CURRENT FCST DEWPOINTS 3-5 DEGF TOO HIGH BASED
ON LATEST OBSERVATIONS. QUITE WARM ON SUNDAY...WITH HIGH TEMPS
REACHING THE MIDDLE 70S /EASTERN UPPER/ TO LOWER 80S /PORTIONS OF
NORTHERN LOWER/. WEAK GRADIENT AND WARM TEMPS LEND ITSELF TO LAKE
BREEZE DEVELOPMENT DURING THE AFTERNOON HOURS AND WILL COOL TEMPS
CLOSER TO THE COASTS TO ACCOUNT FOR THIS. EVEN WITH SLIGHTLY LOWER
DWPTS THAN THE NAM FCST SOUNDINGS...MODIFIED SOUNDINGS WITH NEAR DRY
ADIABATIC MIXED LAYER YIELD SEVERAL HUNDRED JOULES OF SKINNY CAPE.
INLAND PENETRATING LAKE BREEZE BOUNDARIES...INCREASING SFC DWPTS AND
SOME INSTABILITY SUPPORT ISOLATED SHOWER MENTION FOR INTERIOR AREAS
DURING THE MID/LATE AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
MID AND UPPER LEVEL PATTERN BECOMING INCREASINGLY BLOCKY WITH
TIME...AT LEAST PARTIALLY DRIVEN BY STRONG NORTH CENTRAL ATLANTIC
CENTERED HIGH PRESSURE RIDGE AXIS. DUAL STRONG SHORTWAVE TROUGHS
DIVING INTO THE PACIFIC NORTHWEST ONLY HELPING THE CAUSE...WITH LEAD
ENERGY EVENTUALLY CARVING OUT A SLOW MOVING UPPER LOW IN THE NATIONS
MIDSECTION EARLY NEXT WORK WEEK...WHILE THE NEXT PIECE DOES THE SAME
ACROSS THE PACIFIC NORTHWEST. SUBSEQUENT CANADIAN PRAIRIE RIDGE
BUILDING BETWEEN THESE FEATURES SETS UP A QUASI-OMEGA BLOCK
SIGNATURE...WITH STRONG ENERGY PROGGED TO DIVE DOWN ITS FRONTSIDE
INTO EAST CENTRAL CANADA ONLY ADDING FURTHER COMPLEXITY TO AN
ALREADY COMPLEX PATTERN. ADD IN A GOOD SUPPLY OF GULF OF MEXICO
MOISTURE AND FGEN DYNAMICS...AND THE PATTERN HAS ALL THE MAKINGS OF
A WET ONE THROUGH AT LEAST THE FIRST HALF OF THIS UPCOMING WEEK.
LATEST WPC 5 AND 7 DAY QUANTITATIVE PRECIPITATION FORECASTS
CONCUR...WITH WIDESPREAD 1 TO 2 INCH AMOUNTS ACROSS OUR AREA...WITH
HEAVIER AMOUNTS TO UPWARDS OF 4 INCHES JUST TO OUR NORTHWEST. AS ONE
CAN IMAGINE GIVEN ABOVE...EXTENDED FORECAST CONCERNS MAINLY CENTER
ON MULTI-PERIOD RAIN SHOWER AND THUNDERSTORM THREATS.
ONE COMPLICATED FORECAST SUNDAY NIGHT INTO MONDAY...WHICH...TO BE
HONEST...DOES NOT SUPPORT A WHOLE LOT OF FORECAST CONFIDENCE.
CENTRAL PLAINS CLOSED LOW BECOMES INCREASINGLY WELL ESTABLISHED...
WITH EXCELLENT FORCED LOW/MID LEVEL CONVERGENCE ZONE SETTING UP
BETWEEN SOUTH FLOW OUT AHEAD OF IT WEAK ENERGY DIVING THROUGH
ONTARIO. STRONG H8 CONVERGENCE AXIS LOOKS TO SLOWLY SAG SOUTH ACROSS
LAKE SUPERIOR SUNDAY NIGHT INTO MONDAY...WITH SURFACE REFLECTION
ESSENTIALLY REMAINING STATIONARY ACROSS THE CLIMATOLOGICALLY FAVORED
TIP OF THE MITT/STRAITS REGION. H8 FRONT LOOKS TO REMAIN VERY
ACTIVE...FOCUSING MUCH OF THE RAIN OFF TO OUR NORTH THROUGH SUNDAY
NIGHT...PERHAPS INTO THE FIRST PART OF MONDAY (HELPED IN PART BY MID
LEVEL RIDGING REMAINING OVERHEAD). CONDITIONS BECOME MUCH MORE
INTERESTING HEADING INTO MONDAY AFTERNOON AND NIGHT AS ENERGY
ROTATING AROUND UPPER LEVEL LOW INTERACTS WITH AN INCREASINGLY
IMPRESSIVE OVERHEAD MOISTURE PLUME AS PWAT VALUES APPROACH AN INCH
AND A HALF. WHILE MODEL DEPICTED SURFACE DEWPOINTS IN THE UPPER
60S/LOWER 70S SEEM AGGRESSIVE...JUXTAPOSITION OF DECENT MOISTURE AND
MID LEVEL SUPPORT SHOULD BE ENOUGH TO KICK OFF ROUNDS OF SHOWERS AND
STORMS...SOME OF WHICH MAY BRING LOCALLY HEAVY RAINFALL. WHILE
SEVERE THREAT NOT COMPLETELY ZERO...BETTER POTENTIAL SHOULD REMAIN
TO OUR SOUTHWEST WITHIN CORRIDOR OF MUCH MORE IMPRESSIVE DEEP LAYER
SHEAR AND BETTER LOW LEVEL INSTABILITY. LATEST DAY 3 SPC SEVERE
GRAPHICS DOES BRING THE SLIGHT RISK RIGHT TO OUR DOORSTEP OVER
SOUTHWEST MICHIGAN. NO DOUBT WORTH KEEPING AN EYE ON THE NEXT FEW
DAYS AS UPSTREAM CONVECTIVE TRENDS WILL LIKELY PLAY HAVOC WITH EXACT
THERMODYNAMIC AND KINEMATIC DETAILS. POTENTIALLY ANOTHER WARM ONE
MONDAY...ESPECIALLY SOUTH OF THE BRIDGE. THERMAL PROGS EASILY
SUPPORT HIGHS BACK INTO THE LOWER 80S...ALTHOUGH CLOUD AND
CONVECTIVE TRENDS MAY PREVENT FULL WARMING FROM BEING REALIZED.
MID-WEEK WEATHER DEPENDENT ON INTERACTION (OR LACK THEREOF) BETWEEN
APPROACHING MID LEVEL LOW AND STRONGER ENERGY DIVING SOUTH OUT OF
CANADA. THE FORMER CONTINUES TO SUPPLY PLENTY OF MOISTURE AND
DYNAMICS...WHILE THE LATTER ATTEMPTS TO DRIVE BEST FGEN/BAROCLINIC
ZONE FURTHER SOUTH WITH TIME. DEEP LAYER CONVERGENCE AND MOISTURE
SUPPORTS PLENTY OF RAIN POTENTIAL...WITH PLACEMENT OF THE HEAVIEST
AND STEADIEST RAINFALL TIED TO ABOVE INTERACTION. 00Z ECMWF/GEM
OFFER A RATHER WET SCENARIO...KEEPING CORRIDOR OF DEEP LAYER
CONVERGENCE OVERHEAD RIGHT THROUGH THURSDAY. GFS A TOUCH MORE
AGGRESSIVE DRIVING THIS CORRIDOR SOUTH...ALTHOUGH IT TOO SUGGESTS
LINGERING RAINS INTO THURSDAY (JUST NOT AS HEAVY). HARD TO GET A
FEEL FOR WHICH IS MORE CORRECT...WITH THE END RESULT LIKELY A MIDDLE
GROUND BETWEEN THE TWO. INHERITED FORECAST KEEPS RAINS LINGERING
THROUGH THURSDAY...AS WILL THIS FORECAST. SEVERE THREAT SHOULD ONLY
SAG SOUTH WITH TIME AS LOW LEVEL BAROCLINIC ZONE DOES THE SAME. THAT
SAID...PROXIMITY OF IT AND SOME EVIDENCE FOR IT TO RETURN BRIEFLY
NORTH LATER WEDNESDAY...AS MAIN WESTERN ENERGY APPROACHES...
DEFINITELY RAISES SOME CONCERN.
START OF MEMORIAL DAY WEEKEND LOOKING COOL AND DRY AS CANADIAN HIGH
PRESSURE BUILDS OVERHEAD. HIGHS FRIDAY AND SATURDAY LOOK TO ONLY
REACH INTO 60S (UPPER 50S ACROSS EASTERN UPPER?)...WHICH WOULD BE AT
LEAST A FEW DEGREES BELOW NORMAL. PATTERN RECOGNITION SUPPORTS THE
POTENTIAL FOR SOME RATHER CHILLY OVERNIGHT READINGS THURSDAY THROUGH
SATURDAY. SOMEWHAT DISCONCERTING TO SEE LATEST CLIMO INFLUENCED
ECMWF MOS SHOWING COLDER LOCATIONS DIPPING INTO THE MIDDLE AND UPPER
30S EARLY FRIDAY MORNING...AND WIDESPREAD LOWER AND MIDDLE 30 DEGREE
READINGS SATURDAY MORNING. OTHER GUIDANCE NOT QUITE AS COLD...BUT
DEFINITELY SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 728 PM EDT SAT MAY 18 2013
VFR.
LIGHT SOUTHERLY FLOW IN PLACE IN THE LOW AND MID LEVELS...BETWEEN
HIGH PRESSURE OVER EASTERN CANADA...AND LOW PRESSURE IN THE CENTRAL/
SOUTHERN HIGH PLAINS. THIS WILL SLOWLY BRING MORE LOW-LEVEL MOISTURE
INTO THE REGION. INITIALLY...BAND OF MID/HIGH CLOUDS WILL CONTINUE
TO LIFT NORTH OUT OF NORTHERN LOWER TONIGHT. PATCHY MID CLOUDS
WILL RETURN TO NORTHERN LOWER OVERNIGHT FROM THE SOUTH. SUNDAY
WILL BE SUNNIER...WARMER...AND SOMEWHAT MORE HUMID. DEVELOPING LAKE
BREEZES WILL LIKELY TRIGGER A FEW SHRA IN THE AFTERNOON...BUT
INLAND FROM ALL THE TAF SITES.
LIGHT WINDS TONIGHT INTO SUNDAY MORNING...WITH ONSHORE WINDS
DEVELOPING EARLY SUNDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 316 PM EDT SAT MAY 18 2013
GRADIENT WILL REMAIN RELATIVELY WEAK OVER THE NEXT FEW DAYS AS HIGH
PRESSURE SLOWLY DEPARTS TO THE EAST. AS LOW PRESSURE DRAWS CLOSER
TO THE AREA TUESDAY/WEDNESDAY...WINDS WILL INCREASE AND SMALL
CRAFT CONDITIONS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JZ
MARINE...JK
000
FXUS63 KAPX 181927
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
327 PM EDT SAT MAY 18 2013
.SYNOPSIS...
ISSUED AT 316 PM EDT SAT MAY 18 2013
HIGH PRESSURE WILL PROVIDE A LITTLE MORE SUNSHINE...THUS A BIT
WARMER TEMPERATURES FOR SUNDAY. HOWEVER...A STORM SYSTEM DEVELOPING
OVER THE ROCKIES WILL BECOME BETTER ORGANIZED OVER THE
PLAINS...BEFORE MOVING INTO THE GREAT LAKES TO START THE WORK WEEK.
THIS APPROACHING SYSTEM WILL GENERATE THUNDERSTORMS AND MILD
TEMPERATURES...OVER NORTHERN MICHIGAN THROUGH MID WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
ELEVATED WARM FRONT/WARM AIR ADVECTION WING CONTINUES TO LIFT THRU
THE AREA TONIGHT WITH LINGERING MID LEVEL FGEN AND ADIABATIC OMEGA
POSSIBLY PRODUCING A FEW SPRINKLES/LIGHT SHOWER TIP OF THE MITT INTO
EASTERN UPPER. SKY CONDITIONS RANGING FROM PARTLY CLOUDY SOUTH TO
MOSTLY CLOUDY NORTH. A MILD NIGHT WITH LOWS FROM THE MID 40S TO
LOWER 50S.
BY FAR THE BEST DAY OF THE WEEKEND ON SUNDAY WITH 850MB THERMAL
RIDGE OF 13-15C BUILDING INTO THE AREA. MID LEVEL RIDGING WILL
CONTINUE TO DOMINATE OUR WEATHER PICTURE AS DEEPER TROUGH DIGS INTO
THE NORTHERN PLAINS. SFC DEWPOINTS WILL CONTINUE TO GRADUALLY CREEP
UP AS THE DAY PROGRESSES. NAM CONTINUING ITS RECENT BIAS OF TOO WET
LOWER LEVELS...WITH CURRENT FCST DEWPOINTS 3-5 DEGF TOO HIGH BASED
ON LATEST OBSERVATIONS. QUITE WARM ON SUNDAY...WITH HIGH TEMPS
REACHING THE MIDDLE 70S /EASTERN UPPER/ TO LOWER 80S /PORTIONS OF
NORTHERN LOWER/. WEAK GRADIENT AND WARM TEMPS LEND ITSELF TO LAKE
BREEZE DEVELOPMENT DURING THE AFTERNOON HOURS AND WILL COOL TEMPS
CLOSER TO THE COASTS TO ACCOUNT FOR THIS. EVEN WITH SLIGHTLY LOWER
DWPTS THAN THE NAM FCST SOUNDINGS...MODIFIED SOUNDINGS WITH NEAR DRY
ADIABATIC MIXED LAYER YIELD SEVERAL HUNDRED JOULES OF SKINNY CAPE.
INLAND PENETRATING LAKE BREEZE BOUNDARIES...INCREASING SFC DWPTS AND
SOME INSTABILITY SUPPORT ISOLATED SHOWER MENTION FOR INTERIOR AREAS
DURING THE MID/LATE AFTERNOON.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 316 PM EDT SAT MAY 18 2013
MID AND UPPER LEVEL PATTERN BECOMING INCREASINGLY BLOCKY WITH
TIME...AT LEAST PARTIALLY DRIVEN BY STRONG NORTH CENTRAL ATLANTIC
CENTERED HIGH PRESSURE RIDGE AXIS. DUAL STRONG SHORTWAVE TROUGHS
DIVING INTO THE PACIFIC NORTHWEST ONLY HELPING THE CAUSE...WITH LEAD
ENERGY EVENTUALLY CARVING OUT A SLOW MOVING UPPER LOW IN THE NATIONS
MIDSECTION EARLY NEXT WORK WEEK...WHILE THE NEXT PIECE DOES THE SAME
ACROSS THE PACIFIC NORTHWEST. SUBSEQUENT CANADIAN PRAIRIE RIDGE
BUILDING BETWEEN THESE FEATURES SETS UP A QUASI-OMEGA BLOCK
SIGNATURE...WITH STRONG ENERGY PROGGED TO DIVE DOWN ITS FRONTSIDE
INTO EAST CENTRAL CANADA ONLY ADDING FURTHER COMPLEXITY TO AN
ALREADY COMPLEX PATTERN. ADD IN A GOOD SUPPLY OF GULF OF MEXICO
MOISTURE AND FGEN DYNAMICS...AND THE PATTERN HAS ALL THE MAKINGS OF
A WET ONE THROUGH AT LEAST THE FIRST HALF OF THIS UPCOMING WEEK.
LATEST WPC 5 AND 7 DAY QUANTITATIVE PRECIPITATION FORECASTS
CONCUR...WITH WIDESPREAD 1 TO 2 INCH AMOUNTS ACROSS OUR AREA...WITH
HEAVIER AMOUNTS TO UPWARDS OF 4 INCHES JUST TO OUR NORTHWEST. AS ONE
CAN IMAGINE GIVEN ABOVE...EXTENDED FORECAST CONCERNS MAINLY CENTER
ON MULTI-PERIOD RAIN SHOWER AND THUNDERSTORM THREATS.
ONE COMPLICATED FORECAST SUNDAY NIGHT INTO MONDAY...WHICH...TO BE
HONEST...DOES NOT SUPPORT A WHOLE LOT OF FORECAST CONFIDENCE.
CENTRAL PLAINS CLOSED LOW BECOMES INCREASINGLY WELL ESTABLISHED...
WITH EXCELLENT FORCED LOW/MID LEVEL CONVERGENCE ZONE SETTING UP
BETWEEN SOUTH FLOW OUT AHEAD OF IT WEAK ENERGY DIVING THROUGH
ONTARIO. STRONG H8 CONVERGENCE AXIS LOOKS TO SLOWLY SAG SOUTH ACROSS
LAKE SUPERIOR SUNDAY NIGHT INTO MONDAY...WITH SURFACE REFLECTION
ESSENTIALLY REMAINING STATIONARY ACROSS THE CLIMATOLOGICALLY FAVORED
TIP OF THE MITT/STRAITS REGION. H8 FRONT LOOKS TO REMAIN VERY
ACTIVE...FOCUSING MUCH OF THE RAIN OFF TO OUR NORTH THROUGH SUNDAY
NIGHT...PERHAPS INTO THE FIRST PART OF MONDAY (HELPED IN PART BY MID
LEVEL RIDGING REMAINING OVERHEAD). CONDITIONS BECOME MUCH MORE
INTERESTING HEADING INTO MONDAY AFTERNOON AND NIGHT AS ENERGY
ROTATING AROUND UPPER LEVEL LOW INTERACTS WITH AN INCREASINGLY
IMPRESSIVE OVERHEAD MOISTURE PLUME AS PWAT VALUES APPROACH AN INCH
AND A HALF. WHILE MODEL DEPICTED SURFACE DEWPOINTS IN THE UPPER
60S/LOWER 70S SEEM AGGRESSIVE...JUXTAPOSITION OF DECENT MOISTURE AND
MID LEVEL SUPPORT SHOULD BE ENOUGH TO KICK OFF ROUNDS OF SHOWERS AND
STORMS...SOME OF WHICH MAY BRING LOCALLY HEAVY RAINFALL. WHILE
SEVERE THREAT NOT COMPLETELY ZERO...BETTER POTENTIAL SHOULD REMAIN
TO OUR SOUTHWEST WITHIN CORRIDOR OF MUCH MORE IMPRESSIVE DEEP LAYER
SHEAR AND BETTER LOW LEVEL INSTABILITY. LATEST DAY 3 SPC SEVERE
GRAPHICS DOES BRING THE SLIGHT RISK RIGHT TO OUR DOORSTEP OVER
SOUTHWEST MICHIGAN. NO DOUBT WORTH KEEPING AN EYE ON THE NEXT FEW
DAYS AS UPSTREAM CONVECTIVE TRENDS WILL LIKELY PLAY HAVOC WITH EXACT
THERMODYNAMIC AND KINEMATIC DETAILS. POTENTIALLY ANOTHER WARM ONE
MONDAY...ESPECIALLY SOUTH OF THE BRIDGE. THERMAL PROGS EASILY
SUPPORT HIGHS BACK INTO THE LOWER 80S...ALTHOUGH CLOUD AND
CONVECTIVE TRENDS MAY PREVENT FULL WARMING FROM BEING REALIZED.
MID-WEEK WEATHER DEPENDENT ON INTERACTION (OR LACK THEREOF) BETWEEN
APPROACHING MID LEVEL LOW AND STRONGER ENERGY DIVING SOUTH OUT OF
CANADA. THE FORMER CONTINUES TO SUPPLY PLENTY OF MOISTURE AND
DYNAMICS...WHILE THE LATTER ATTEMPTS TO DRIVE BEST FGEN/BAROCLINIC
ZONE FURTHER SOUTH WITH TIME. DEEP LAYER CONVERGENCE AND MOISTURE
SUPPORTS PLENTY OF RAIN POTENTIAL...WITH PLACEMENT OF THE HEAVIEST
AND STEADIEST RAINFALL TIED TO ABOVE INTERACTION. 00Z ECMWF/GEM
OFFER A RATHER WET SCENARIO...KEEPING CORRIDOR OF DEEP LAYER
CONVERGENCE OVERHEAD RIGHT THROUGH THURSDAY. GFS A TOUCH MORE
AGGRESSIVE DRIVING THIS CORRIDOR SOUTH...ALTHOUGH IT TOO SUGGESTS
LINGERING RAINS INTO THURSDAY (JUST NOT AS HEAVY). HARD TO GET A
FEEL FOR WHICH IS MORE CORRECT...WITH THE END RESULT LIKELY A MIDDLE
GROUND BETWEEN THE TWO. INHERITED FORECAST KEEPS RAINS LINGERING
THROUGH THURSDAY...AS WILL THIS FORECAST. SEVERE THREAT SHOULD ONLY
SAG SOUTH WITH TIME AS LOW LEVEL BAROCLINIC ZONE DOES THE SAME. THAT
SAID...PROXIMITY OF IT AND SOME EVIDENCE FOR IT TO RETURN BRIEFLY
NORTH LATER WEDNESDAY...AS MAIN WESTERN ENERGY APPROACHES...
DEFINITELY RAISES SOME CONCERN.
START OF MEMORIAL DAY WEEKEND LOOKING COOL AND DRY AS CANADIAN HIGH
PRESSURE BUILDS OVERHEAD. HIGHS FRIDAY AND SATURDAY LOOK TO ONLY
REACH INTO 60S (UPPER 50S ACROSS EASTERN UPPER?)...WHICH WOULD BE AT
LEAST A FEW DEGREES BELOW NORMAL. PATTERN RECOGNITION SUPPORTS THE
POTENTIAL FOR SOME RATHER CHILLY OVERNIGHT READINGS THURSDAY THROUGH
SATURDAY. SOMEWHAT DISCONCERTING TO SEE LATEST CLIMO INFLUENCED
ECMWF MOS SHOWING COLDER LOCATIONS DIPPING INTO THE MIDDLE AND UPPER
30S EARLY FRIDAY MORNING...AND WIDESPREAD LOWER AND MIDDLE 30 DEGREE
READINGS SATURDAY MORNING. OTHER GUIDANCE NOT QUITE AS COLD...BUT
DEFINITELY SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM EDT SAT MAY 18 2013
VFR CONDITIONS EXPECTED THROUGHOUT THE PERIOD. WARM FRONT WILL
MOVE NORTH OF THE AREA THROUGH TONIGHT WITH MID CLOUDS AND
A FEW SPRINKLES. SCATTERED DIURNAL CU FIELDS ON SUNDAY WITH BASES
FROM 5-6K. LIGHT WINDS THROUGHOUT...WITH LAKE BREEZE DEVELOPMENT
CLOSER TO THE COASTS ON SUNDAY.
&&
.MARINE...
ISSUED AT 316 PM EDT SAT MAY 18 2013
GRADIENT WILL REMAIN RELATIVELY WEAK OVER THE NEXT FEW DAYS AS HIGH
PRESSURE SLOWLY DEPARTS TO THE EAST. AS LOW PRESSURE DRAWS CLOSER
TO THE AREA TUESDAY/WEDNESDAY...WINDS WILL INCREASE AND SMALL
CRAFT CONDITIONS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...KB
SHORT TERM...JK
LONG TERM...MB
AVIATION...JK
MARINE...JK
000
FXUS63 KAPX 181701
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
101 PM EDT SAT MAY 18 2013
.SYNOPSIS...
ISSUED AT 317 AM EDT SAT MAY 18 2013
HIGH PRESSURE WILL EXIT TO THE EAST...ALLOWING FOR WARMER CONDITIONS
ALONG WITH A CHANCE FOR SHOWERS OVER THE WEEKEND. A STORM SYSTEM
CURRENTLY ORGANIZING OVER THE ROCKIES WILL MOVE INTO THE PLAINS
TODAY...AND INTO THE GREAT LAKES TO START THE WORK WEEK. THIS WILL
GENERATE SHOWERS AND THUNDERSTORMS OVER NORTHERN MICHIGAN BEGINNING
MONDAY AND CONTINUING THROUGH MIDWEEK.
&&
.UPDATE...
ISSUED AT 1244 PM EDT SAT MAY 18 2013
THICKEST MID/HIGH CLOUD SHIELD GRADUALLY LIFTING TO THE NORTHEAST
WITH ELEVATED WARM FRONT/MID LEVEL ADIABATIC OMEGA. STILL A FEW
SPRINKLES/LIGHT RAIN SHOWERS...BUT PCPN COVERAGE HAS BEEN
DIMINISHING OVER THE PAST FEW HOURS. WILL MAKE A FEW ADJUSTMENTS
TO SKY COVER...WITH INCREASING SUNSHINE FROM SOUTHWEST TO
NORTHEAST AS THE AFTERNOON PROGRESSES. STILL MAY BE DIFFICULT TO
LOSE THE CLOUDS FROM THE TIP OF THE MITT INTO EASTERN UPPER.
WARMEST TEMPS /MID 70S/ TO THE SOUTHWEST WHERE SUNSHINE WILL BE
GREATEST.
UPDATE ISSUED AT 948 AM EDT SAT MAY 18 2013
ELEVATED WARM FRONT GRADUALLY SLIDING TO THE NORTH THIS MORNING
WITH DEEPEST FORCING/MOISTURE REMAINING WEST OF OUR AREA. DESPITE
LITTLE MOISTURE BELOW 800MB ACROSS NORTHERN MICHIGAN...STILL
ENOUGH FORCING TO CREATE PATCHY LIGHT RAIN AND SPRINKLES /SPOTTER
REPORTS UP TO 0.06 INCHES OF RAIN/. FORCING WILL DIMINISH OVER THE
NEXT SEVERAL HOURS AS EVERYTHING GRADUALLY PUSHES TO THE NORTH.
EXPECT CURRENT AREA OF LIGHT PCPN TO GRADUALLY DIMINISH THROUGH
EARLY AFTERNOON AS IT PUSHES INTO EASTERN UPPER/TIP OF THE MITT.
LIKELY STILL SOME SPRINKLES OVER PORTIONS OF NORTHERN LOWER INTO
THE AFTERNOON WITH LINGERING FORCING AND PLENTY OF MID CLOUD.
PREVAILING CLOUDY SKIES TODAY...WITH SOME BREAKS LIKELY OVER
SRN/SW AREAS. LOWERED TEMPS IN MANY AREAS THIS AFTERNOON...ESPECIALLY
GAYLORD NORTHWARD WITH MORE CLOUDS AND LIGHT PCPN.
UPDATE ISSUED AT 650 AM EDT SAT MAY 18 2013
ISOLD LIGHT SHOWERS CONTINUE TO IMPACT THE SW HALF OF OUR CWA
EARLY THIS MORNING AS LIMITED LOW/MID LEVEL MOISTURE LIFT INTO NRN
MICHIGAN NORTH OF A WARM FRONT. THUNDERSTORMS CONTINUE TO FIRE
WELL UPSTREAM OVER MINNESOTA IN THE VCNTY OF AN 850 MB THETA E
RIDGE AND INSTABILITY AXIS. LATEST NAM STILL POINTS TOWARD THIS
INSTABILITY AND DEEPER MOISTURE REMAINING UPSTREAM OF OUR CWA THRU
THE DAY...WITH ONLY SOME ISOLATED SHOWERS AND MAINLY CLOUDY SKIES
EXPECTED FOR US TODAY. THESE ISOLD SHOWERS WILL GRADUALLY LIFT
NORTHWARD INTO THE REST OF OUR CWA THRU THE DAY AS THE WARM FRONT
EDGES CLOSER. NO CHANGES ARE NEEDED TO THE TIMING OF WX/POPS FOR
NOW.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 317 AM EDT SAT MAY 18 2013
ON THE LATEST SURFACE WEATHER MAP...1025 MB HIGH PRESSURE WAS
CENTERED OVER SOUTHEAST ONTARIO WITH 1002 MB LOW PRESSURE ALONG THE
FRONT RANGE OF THE CENTRAL ROCKIES. APX AND SURROUNDING RADARS
SHOWED A FEW LIGHT RAIN SHOWERS SPRINKLED ACROSS PORTIONS OF NORTH
CENTRAL LOWER MICHIGAN. THE MAIN SHORT TERM FORECAST CONCERNS CENTER
AROUND POPS AND HIGH TEMPERATURES TODAY.
TODAY INTO TONIGHT...MORE OF THE SAME WITH SUBTLE WARM FRONT AND
INCREASING THETA-E RIDGING (MOISTURE) ADVECTING INTO THE REGION FROM
THE SOUTHWEST. THE MAIN FORCING/BETTER MOISTURE REMAIN TO OUR WEST
CLOSER TO PARENT UPPER LOW SPINNING ITS WHEELS ACROSS THE ROCKIES.
LOOKING AT MODEL CROSS SECTIONS...LOWER LEVELS REMAIN RATHER DRY
WITH ABUNDANT MID LEVEL MOISTURE (FROM ABOUT 850 TO JUST BELOW 500
MB). SO EXPECT MOSTLY CLOUDY SKIES WITH ISOLATED LIGHT RAIN SHOWERS
MARCHING FROM SOUTHWEST TO NORTHEAST THROUGH THE DAY. MAINLY DRY
TONIGHT WITH PERHAPS JUST A FEW LEFTOVER ISOLATED RAIN SHOWERS
ACROSS THE FAR NORTH. TEMPERATURES ARE A BIT TRICKY TODAY WITH
ABUNDANT CLOUD COVER AND WEAK WARM ADVECTION. HIGHS EXPECTED TO
RANGE FROM THE MIDDLE 60S NORTH TO THE MIDDLE 70S SOUTH. LOWS
TONIGHT RANGING FROM THE MIDDLE 40S TO LOWER 50S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 317 AM EDT SAT MAY 18 2013
SUNDAY...WILL BE THE BEST WEATHER DAY OF THE WEEKEND. ERN EDGE OF A
WARM FRONT WILL LIFT NORTHWARD INTO UPPER MICHIGAN. SOUTHERLY FLOW
SOUTH OF THE WARM FRONT WILL BOOST TEMPS INTO THE LOW TO MID 70S
ACROSS ERN UPR MICHIGAN AND INTO THE UPPER 70S AND LOWER 80S ACROSS
NRN LWR MICHIGAN. STILL APPEARS SUNDAY WILL BE DRY WITH PARTLY SUNNY
SKIES...AND WILL LIKELY SERVE AS OUR LAST COMPLETELY DRY DAY FOR
MOST OF NEXT WORK WEEK (MORE ON THIS BELOW). AT THIS POINT...SUNDAY
EVENING SHOULD REMAIN DRY...BUT PRECIP CHANCES WILL BEGIN TO
INCREASE ACROSS OUR WRN CWA LATE SUNDAY NIGHT AS AN INITIAL SHORT
WAVE ACCOMPANIED BY BETTER MOISTURE ARRIVE TOWARD DAYBREAK.
MONDAY THRU WEDNESDAY...PRECIP CHANCES WILL CONTINUE TO INCREASE
FROM WEST TO EAST ON MONDAY AS THE WARM FRONT SAGS SOUTHWARD INTO
NRN LWR MICHIGAN. DEVELOPING LOW PRESSURE IN THE PLAINS WILL BEGIN
TO TAP INTO GULF MOISTURE...ADVECTING IT NORTHWARD THRU THE LOWER
AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. AS THIS
DEEPER MOISTURE BEGINS TO INTERACT WITH THE WARM FRONT AND A SERIES
OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING UPPER
LOWER...WAVES OF SHOWERS AND STORMS WILL REMAIN THE RULE BEGINNING
MONDAY AND CONTINUING THRU WEDNESDAY NIGHT. SURFACE AND CLOSED UPPER
LOW BECOME VERTICALLY STACKED...THUS MAKING VERY SLOW EASTWARD
PROGRESS OVER THIS TIME PERIOD...AND THEREFORE KEEPING OUR WEATHER
UNSETTLED THRU MID WEEK (AT LEAST). WARM TEMPS WILL HOLD OVER THE
REGION ON MONDAY BEFORE THE WARM FRONT SAGS SOUTH ON TUESDAY AND
WEDNESDAY. HIGH TEMPS ON MONDAY WILL RANGE FROM AROUND 70 DEGREES
ACROSS ERN UPR MICHIGAN NORTH OF THE WARM FRONT TO THE MID 70S TO
LOWER 80S SOUTH OF THE WARM FRONT. HIGH TEMPS WILL ONLY REACH INTO
THE 60S BOTH TUESDAY AND WEDNESDAY AS THE WARM FRONT CONTINUES TO
DROP SOUTH OF OUR CWA.
THURSDAY AND FRIDAY...SURFACE AND UPPER LOW CENTERS WILL SLOWLY
SLIDE THRU LWR MICHIGAN ON THURSDAY...EXITING EAST TOWARD NEW
ENGLAND BY FRIDAY. SOME SHOWERS WILL LINGER ACROSS OUR CWA THURSDAY
AROUND AND JUST NORTH OF THE SURFACE LOW CENTER...BUT SHOULD COME TO
AN END BY FRIDAY AS DRIER AIR FILTERS INTO THE REGION BEHIND THE
DEPARTING LOW. THE COLDER AIR BEHIND THIS SYSTEM WILL NOT ARRIVE
UNTIL SATURDAY. NEUTRAL TEMP ADVECTION WILL LEND TO HIGH TEMPS
REMAINING IN THE 60S FOR BOTH THURSDAY AND FRIDAY. A FIRST LOOK AT
NEXT WEEKEND LOOKS DRY BUT POTENTIALLY COOLER THAN NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM EDT SAT MAY 18 2013
VFR CONDITIONS EXPECTED THROUGHOUT THE PERIOD. WARM FRONT WILL
MOVE NORTH OF THE AREA THROUGH TONIGHT WITH MID CLOUDS AND
A FEW SPRINKLES. SCATTERED DIURNAL CU FIELDS ON SUNDAY WITH BASES
FROM 5-6K. LIGHT WINDS THROUGHOUT...WITH LAKE BREEZE DEVELOPMENT
CLOSER TO THE COASTS ON SUNDAY.
&&
.MARINE...
ISSUED AT 317 AM EDT SAT MAY 18 2013
SOUTH-SOUTHEAST FLOW SLOWLY INCREASES TODAY THROUGH SUNDAY...AND A
HANDFUL OF SMALL CRAFT ADVISORIES MAY BE NEEDED AT SOME POINT LATER
IN THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JK
SYNOPSIS...MR
SHORT TERM...AS
LONG TERM...MR
AVIATION...JK
MARINE...AS
000
FXUS63 KAPX 181410
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1010 AM EDT SAT MAY 18 2013
.SYNOPSIS...
ISSUED AT 317 AM EDT SAT MAY 18 2013
HIGH PRESSURE WILL EXIT TO THE EAST...ALLOWING FOR WARMER CONDITIONS
ALONG WITH A CHANCE FOR SHOWERS OVER THE WEEKEND. A STORM SYSTEM
CURRENTLY ORGANIZING OVER THE ROCKIES WILL MOVE INTO THE PLAINS
TODAY...AND INTO THE GREAT LAKES TO START THE WORK WEEK. THIS WILL
GENERATE SHOWERS AND THUNDERSTORMS OVER NORTHERN MICHIGAN BEGINNING
MONDAY AND CONTINUING THROUGH MIDWEEK.
&&
.UPDATE...
ISSUED AT 948 AM EDT SAT MAY 18 2013
ELEVATED WARM FRONT GRADUALLY SLIDING TO THE NORTH THIS MORNING
WITH DEEPEST FORCING/MOISTURE REMAINING WEST OF OUR AREA. DESPITE
LITTLE MOISTURE BELOW 800MB ACROSS NORTHERN MICHIGAN...STILL
ENOUGH FORCING TO CREATE PATCHY LIGHT RAIN AND SPRINKLES /SPOTTER
REPORTS UP TO 0.06 INCHES OF RAIN/. FORCING WILL DIMINISH OVER THE
NEXT SEVERAL HOURS AS EVERYTHING GRADUALLY PUSHES TO THE NORTH.
EXPECT CURRENT AREA OF LIGHT PCPN TO GRADUALLY DIMINISH THROUGH
EARLY AFTERNOON AS IT PUSHES INTO EASTERN UPPER/TIP OF THE MITT.
LIKELY STILL SOME SPRINKLES OVER PORTIONS OF NORTHERN LOWER INTO
THE AFTERNOON WITH LINGERING FORCING AND PLENTY OF MID CLOUD.
PREVAILING CLOUDY SKIES TODAY...WITH SOME BREAKS LIKELY OVER
SRN/SW AREAS. LOWERED TEMPS IN MANY AREAS THIS AFTERNOON...ESPECIALLY
GAYLORD NORTHWARD WITH MORE CLOUDS AND LIGHT PCPN.
UPDATE ISSUED AT 650 AM EDT SAT MAY 18 2013
ISOLD LIGHT SHOWERS CONTINUE TO IMPACT THE SW HALF OF OUR CWA
EARLY THIS MORNING AS LIMITED LOW/MID LEVEL MOISTURE LIFT INTO NRN
MICHIGAN NORTH OF A WARM FRONT. THUNDERSTORMS CONTINUE TO FIRE
WELL UPSTREAM OVER MINNESOTA IN THE VCNTY OF AN 850 MB THETA E
RIDGE AND INSTABILITY AXIS. LATEST NAM STILL POINTS TOWARD THIS
INSTABILITY AND DEEPER MOISTURE REMAINING UPSTREAM OF OUR CWA THRU
THE DAY...WITH ONLY SOME ISOLATED SHOWERS AND MAINLY CLOUDY SKIES
EXPECTED FOR US TODAY. THESE ISOLD SHOWERS WILL GRADUALLY LIFT
NORTHWARD INTO THE REST OF OUR CWA THRU THE DAY AS THE WARM FRONT
EDGES CLOSER. NO CHANGES ARE NEEDED TO THE TIMING OF WX/POPS FOR
NOW.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 317 AM EDT SAT MAY 18 2013
ON THE LATEST SURFACE WEATHER MAP...1025 MB HIGH PRESSURE WAS
CENTERED OVER SOUTHEAST ONTARIO WITH 1002 MB LOW PRESSURE ALONG THE
FRONT RANGE OF THE CENTRAL ROCKIES. APX AND SURROUNDING RADARS
SHOWED A FEW LIGHT RAIN SHOWERS SPRINKLED ACROSS PORTIONS OF NORTH
CENTRAL LOWER MICHIGAN. THE MAIN SHORT TERM FORECAST CONCERNS CENTER
AROUND POPS AND HIGH TEMPERATURES TODAY.
TODAY INTO TONIGHT...MORE OF THE SAME WITH SUBTLE WARM FRONT AND
INCREASING THETA-E RIDGING (MOISTURE) ADVECTING INTO THE REGION FROM
THE SOUTHWEST. THE MAIN FORCING/BETTER MOISTURE REMAIN TO OUR WEST
CLOSER TO PARENT UPPER LOW SPINNING ITS WHEELS ACROSS THE ROCKIES.
LOOKING AT MODEL CROSS SECTIONS...LOWER LEVELS REMAIN RATHER DRY
WITH ABUNDANT MID LEVEL MOISTURE (FROM ABOUT 850 TO JUST BELOW 500
MB). SO EXPECT MOSTLY CLOUDY SKIES WITH ISOLATED LIGHT RAIN SHOWERS
MARCHING FROM SOUTHWEST TO NORTHEAST THROUGH THE DAY. MAINLY DRY
TONIGHT WITH PERHAPS JUST A FEW LEFTOVER ISOLATED RAIN SHOWERS
ACROSS THE FAR NORTH. TEMPERATURES ARE A BIT TRICKY TODAY WITH
ABUNDANT CLOUD COVER AND WEAK WARM ADVECTION. HIGHS EXPECTED TO
RANGE FROM THE MIDDLE 60S NORTH TO THE MIDDLE 70S SOUTH. LOWS
TONIGHT RANGING FROM THE MIDDLE 40S TO LOWER 50S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 317 AM EDT SAT MAY 18 2013
SUNDAY...WILL BE THE BEST WEATHER DAY OF THE WEEKEND. ERN EDGE OF A
WARM FRONT WILL LIFT NORTHWARD INTO UPPER MICHIGAN. SOUTHERLY FLOW
SOUTH OF THE WARM FRONT WILL BOOST TEMPS INTO THE LOW TO MID 70S
ACROSS ERN UPR MICHIGAN AND INTO THE UPPER 70S AND LOWER 80S ACROSS
NRN LWR MICHIGAN. STILL APPEARS SUNDAY WILL BE DRY WITH PARTLY SUNNY
SKIES...AND WILL LIKELY SERVE AS OUR LAST COMPLETELY DRY DAY FOR
MOST OF NEXT WORK WEEK (MORE ON THIS BELOW). AT THIS POINT...SUNDAY
EVENING SHOULD REMAIN DRY...BUT PRECIP CHANCES WILL BEGIN TO
INCREASE ACROSS OUR WRN CWA LATE SUNDAY NIGHT AS AN INITIAL SHORT
WAVE ACCOMPANIED BY BETTER MOISTURE ARRIVE TOWARD DAYBREAK.
MONDAY THRU WEDNESDAY...PRECIP CHANCES WILL CONTINUE TO INCREASE
FROM WEST TO EAST ON MONDAY AS THE WARM FRONT SAGS SOUTHWARD INTO
NRN LWR MICHIGAN. DEVELOPING LOW PRESSURE IN THE PLAINS WILL BEGIN
TO TAP INTO GULF MOISTURE...ADVECTING IT NORTHWARD THRU THE LOWER
AND MID MISSISSIPPI VALLEY AND INTO THE WRN GREAT LAKES. AS THIS
DEEPER MOISTURE BEGINS TO INTERACT WITH THE WARM FRONT AND A SERIES
OF SHORT WAVES RIDING NE THRU MICHIGAN AHEAD OF THE DEEPENING UPPER
LOWER...WAVES OF SHOWERS AND STORMS WILL REMAIN THE RULE BEGINNING
MONDAY AND CONTINUING THRU WEDNESDAY NIGHT. SURFACE AND CLOSED UPPER
LOW BECOME VERTICALLY STACKED...THUS MAKING VERY SLOW EASTWARD
PROGRESS OVER THIS TIME PERIOD...AND THEREFORE KEEPING OUR WEATHER
UNSETTLED THRU MID WEEK (AT LEAST). WARM TEMPS WILL HOLD OVER THE
REGION ON MONDAY BEFORE THE WARM FRONT SAGS SOUTH ON TUESDAY AND
WEDNESDAY. HIGH TEMPS ON MONDAY WILL RANGE FROM AROUND 70 DEGREES
ACROSS ERN UPR MICHIGAN NORTH OF THE WARM FRONT TO THE MID 70S TO
LOWER 80S SOUTH OF THE WARM FRONT. HIGH TEMPS WILL ONLY REACH INTO
THE 60S BOTH TUESDAY AND WEDNESDAY AS THE WARM FRONT CONTINUES TO
DROP SOUTH OF OUR CWA.
THURSDAY AND FRIDAY...SURFACE AND UPPER LOW CENTERS WILL SLOWLY
SLIDE THRU LWR MICHIGAN ON THURSDAY...EXITING EAST TOWARD NEW
ENGLAND BY FRIDAY. SOME SHOWERS WILL LINGER ACROSS OUR CWA THURSDAY
AROUND AND JUST NORTH OF THE SURFACE LOW CENTER...BUT SHOULD COME TO
AN END BY FRIDAY AS DRIER AIR FILTERS INTO THE REGION BEHIND THE
DEPARTING LOW. THE COLDER AIR BEHIND THIS SYSTEM WILL NOT ARRIVE
UNTIL SATURDAY. NEUTRAL TEMP ADVECTION WILL LEND TO HIGH TEMPS
REMAINING IN THE 60S FOR BOTH THURSDAY AND FRIDAY. A FIRST LOOK AT
NEXT WEEKEND LOOKS DRY BUT POTENTIALLY COOLER THAN NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 650 AM EDT SAT MAY 18 2013
BKN/OVC MID CLOUD WILL REMAIN OVER ALL OF NRN LWR MICHIGAN THRU
SUNDAY MORNING THANKS TO MID LEVEL MOISTURE NORTH OF A WARM FRONT
TO OUR SOUTH. SCT/BKN LOW CLOUDS AND A FEW SHOWERS ARE EXPECTED TO
IMPACT PORTIONS OF NRN LWR MICHIGAN THRU THE DAY AS WELL...BUT VFR
CONDITIONS WILL REMAIN THE RULE FOR THE NEXT 24 HOURS. SOUTHEAST
WINDS WILL STRENGTHEN TO AROUND 10 KTS THIS MORNING.
&&
.MARINE...
ISSUED AT 317 AM EDT SAT MAY 18 2013
SOUTH-SOUTHEAST FLOW SLOWLY INCREASES TODAY THROUGH SUNDAY...AND A
HANDFUL OF SMALL CRAFT ADVISORIES MAY BE NEEDED AT SOME POINT LATER
IN THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JK
SYNOPSIS...MR
SHORT TERM...AS
LONG TERM...MR
AVIATION...MR
MARINE...AS
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