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000
FXUS65 KSLC 030248
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
848 PM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...THE FORECAST AREA REMAINS UNDER A BREEZY SOUTHWEST
FLOW THIS EVENING BETWEEN THE RIDGE OVER THE CENTRAL UNITED STATES
AND THE BROAD TROUGH APPROACHING THE PACIFIC NORTHWEST COAST. THE
AIRMASS DRIED CONSIDERABLY TODAY AND BECAUSE OF THIS CONVECTION
WAS MUCH MORE ISOLATED THAN IT HAD BEEN PREVIOUS DAYS. ANY
RESIDUAL STORMS HAVE DISSIPATED WITH THE LOSS OF DAYTIME HEATING.
SOME WIND GUSTS IN THE 30-40 KT RANGE HAVE BEEN OBSERVED
TODAY...BUT RIGHT NOW MOST OBSERVED GUSTS REMAIN IN THE 15-25 KT
RANGE.

MODELS INDICATE THAT THE SOUTHWEST FLOW WILL BRING SOME MOISTURE
BACK INTO THE SOUTHWEST UNITED STATES TOMORROW. THE EC KEEPS THIS
MOISTURE SURGE PRIMARILY OVER ARIZONA...NEW MEXICO...AND COLORADO.
HOWEVER...GFS AND NAM HAVE BEEN CONSISTENT IN BRINGING SOME OF
THIS MOISTURE INTO EASTERN UTAH. THIS MOISTURE WOULD BRING AN
INCREASED THREAT OF SHOWERS AND THUNDERSTORMS TOMORROW AND FRIDAY
OVER THE EAST. AS THE PACIFIC NORTHWEST TROUGH INCHES
EASTWARD...FLOW ALOFT OVER THE CWA WILL CONTINUE TO
INCREASE...ESPECIALLY OVER WESTERN UTAH. LATEST GFS INDICATES
WIDESPREAD AREAS OF 30 KT 700 MB FLOW...WITH UP TO 50 KTS FRIDAY
NIGHT/SATURDAY MORNING.

THE TROUGH IS PROGGED TO DIG SOUTHWARD INTO CALIFORNIA AND NEVADA
FRIDAY THROUGH SATURDAY MORNING BEFORE SWEEPING EASTWARD THROUGH
NORTHERN UTAH SATURDAY AFTERNOON THROUGH SATURDAY NIGHT...A BIT
FASTER THAN WHAT GUIDANCE WAS INDICATING AT THIS TIME YESTERDAY.
THE PASSAGE OF THE TROUGH WILL PUSH A SIGNIFICANT COLD FRONT INTO
NORTHERN AND CENTRAL UTAH. THE FRONTAL PASSAGE SHOULD BE MOSTLY
DRY BUT WILL COOL TEMPERATURES SIGNIFICANTLY...WITH 700 MB TEMPS
DROPPING FROM UP TO +12C FRIDAY AFTERNOON TO AS LOW AS +1C OR +2C
OVER NORTHERN UTAH SATURDAY AFTERNOON. BY SUNDAY...MAXES OVER
NORTHERN UTAH ARE PROGGED TO BE UP TO 15F BELOW SEASONAL NORMALS.
HOWEVER...A DRIER SOUTHWEST FLOW BEHIND THE EXITING TROUGH WILL
ALLOW TEMPERATURES TO WARM QUICKLY OVER UTAH AND SOUTHWEST WYOMING
FOR EARLY NEXT WEEK.

NO UPDATES EXPECTED TO THE FORECAST THIS EVENING.

&&

.AVIATION...THE SLC TERMINAL WILL SEE VFR CONDITIONS THROUGH THE
NIGHT WITH SOME HIGH CLOUDS. SOUTHERLY WINDS ARE EXPECTED THROUGH
THE OVERNIGHT HOURS...BECOMING GUSTY AT TIMES DURING THE EARLY
MORNING.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS
THE WESTERN HALF OF THE AREA THURSDAY INTO FRIDAY. IN ADDITION TO
THE GUSTY WINDS...HUMIDITY VALUES ARE EXPECTED TO FALL BELOW 15
PERCENT EACH AFTERNOON WITH POOR OVERNIGHT RECOVERIES. FURTHER
EAST...MOISTURE IS EXPECTED TO INCREASE ACROSS THE EASTERN HALF
OF UTAH THURSDAY INTO FRIDAY BRINGING A RETURN OF SHOWERS AND
THUNDERSTORMS. THE UPSTREAM TROUGH IS FORECAST TO SWING THROUGH
THE REGION SATURDAY BRINGING A CHANCE FOR PRECIPITATION TO
NORTHERN AND CENTRAL UTAH. WINDS WILL ALSO REMAIN ELEVATED ACROSS
MOST VALLEYS THROUGH THE DAY SATURDAY. A MUCH COOLER AIRMASS WILL
FOLLOW THIS SYSTEM FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277.

&&

$$

TRAPHAGAN/SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 030248
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
848 PM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...THE FORECAST AREA REMAINS UNDER A BREEZY SOUTHWEST
FLOW THIS EVENING BETWEEN THE RIDGE OVER THE CENTRAL UNITED STATES
AND THE BROAD TROUGH APPROACHING THE PACIFIC NORTHWEST COAST. THE
AIRMASS DRIED CONSIDERABLY TODAY AND BECAUSE OF THIS CONVECTION
WAS MUCH MORE ISOLATED THAN IT HAD BEEN PREVIOUS DAYS. ANY
RESIDUAL STORMS HAVE DISSIPATED WITH THE LOSS OF DAYTIME HEATING.
SOME WIND GUSTS IN THE 30-40 KT RANGE HAVE BEEN OBSERVED
TODAY...BUT RIGHT NOW MOST OBSERVED GUSTS REMAIN IN THE 15-25 KT
RANGE.

MODELS INDICATE THAT THE SOUTHWEST FLOW WILL BRING SOME MOISTURE
BACK INTO THE SOUTHWEST UNITED STATES TOMORROW. THE EC KEEPS THIS
MOISTURE SURGE PRIMARILY OVER ARIZONA...NEW MEXICO...AND COLORADO.
HOWEVER...GFS AND NAM HAVE BEEN CONSISTENT IN BRINGING SOME OF
THIS MOISTURE INTO EASTERN UTAH. THIS MOISTURE WOULD BRING AN
INCREASED THREAT OF SHOWERS AND THUNDERSTORMS TOMORROW AND FRIDAY
OVER THE EAST. AS THE PACIFIC NORTHWEST TROUGH INCHES
EASTWARD...FLOW ALOFT OVER THE CWA WILL CONTINUE TO
INCREASE...ESPECIALLY OVER WESTERN UTAH. LATEST GFS INDICATES
WIDESPREAD AREAS OF 30 KT 700 MB FLOW...WITH UP TO 50 KTS FRIDAY
NIGHT/SATURDAY MORNING.

THE TROUGH IS PROGGED TO DIG SOUTHWARD INTO CALIFORNIA AND NEVADA
FRIDAY THROUGH SATURDAY MORNING BEFORE SWEEPING EASTWARD THROUGH
NORTHERN UTAH SATURDAY AFTERNOON THROUGH SATURDAY NIGHT...A BIT
FASTER THAN WHAT GUIDANCE WAS INDICATING AT THIS TIME YESTERDAY.
THE PASSAGE OF THE TROUGH WILL PUSH A SIGNIFICANT COLD FRONT INTO
NORTHERN AND CENTRAL UTAH. THE FRONTAL PASSAGE SHOULD BE MOSTLY
DRY BUT WILL COOL TEMPERATURES SIGNIFICANTLY...WITH 700 MB TEMPS
DROPPING FROM UP TO +12C FRIDAY AFTERNOON TO AS LOW AS +1C OR +2C
OVER NORTHERN UTAH SATURDAY AFTERNOON. BY SUNDAY...MAXES OVER
NORTHERN UTAH ARE PROGGED TO BE UP TO 15F BELOW SEASONAL NORMALS.
HOWEVER...A DRIER SOUTHWEST FLOW BEHIND THE EXITING TROUGH WILL
ALLOW TEMPERATURES TO WARM QUICKLY OVER UTAH AND SOUTHWEST WYOMING
FOR EARLY NEXT WEEK.

NO UPDATES EXPECTED TO THE FORECAST THIS EVENING.

&&

.AVIATION...THE SLC TERMINAL WILL SEE VFR CONDITIONS THROUGH THE
NIGHT WITH SOME HIGH CLOUDS. SOUTHERLY WINDS ARE EXPECTED THROUGH
THE OVERNIGHT HOURS...BECOMING GUSTY AT TIMES DURING THE EARLY
MORNING.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS
THE WESTERN HALF OF THE AREA THURSDAY INTO FRIDAY. IN ADDITION TO
THE GUSTY WINDS...HUMIDITY VALUES ARE EXPECTED TO FALL BELOW 15
PERCENT EACH AFTERNOON WITH POOR OVERNIGHT RECOVERIES. FURTHER
EAST...MOISTURE IS EXPECTED TO INCREASE ACROSS THE EASTERN HALF
OF UTAH THURSDAY INTO FRIDAY BRINGING A RETURN OF SHOWERS AND
THUNDERSTORMS. THE UPSTREAM TROUGH IS FORECAST TO SWING THROUGH
THE REGION SATURDAY BRINGING A CHANCE FOR PRECIPITATION TO
NORTHERN AND CENTRAL UTAH. WINDS WILL ALSO REMAIN ELEVATED ACROSS
MOST VALLEYS THROUGH THE DAY SATURDAY. A MUCH COOLER AIRMASS WILL
FOLLOW THIS SYSTEM FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277.

&&

$$

TRAPHAGAN/SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 022153
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
353 PM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (THROUGH 06Z SATURDAY)...SOUTHWESTERLY FLOW ALOFT
PREVAILS ACROSS THE GREAT BASIN THIS AFTERNOON...DOWNSTREAM FROM A
MID LEVEL TROUGH SITUATED ALONG THE WEST COAST. THIS FLOW HAS
GRADUALLY DRIED THE AIRMASS ACROSS THE FORECAST AREA OVER THE PAST
COUPLE OF DAYS...RESULTING IN VERY SHALLOW CU DEVELOPMENT ACROSS
THE HIGHER TERRAIN OF SOUTHERN UT...AND ONLY VERY ISOLATED SHOWERS
ACROSS THE NORTH. HAVE MAINTAINED SLIGHT CHANCE WITHIN A
RELATIVELY NARROW AXIS OF MID LEVEL MOISTURE ACROSS NORTHWEST UT
THIS EVENING.

THE WEST COAST TROUGH IS FORECAST TO SLOWLY DEEPEN THROUGH THE
SHORT TERM PERIOD...STRENGTHENING THE FLOW DOWNSTREAM ACROSS THE
EASTERN GREAT BASIN AND RESULTING IN BREEZY TO WINDY CONDITIONS
ACROSS WESTERN UT BOTH THURSDAY AND FRIDAY. AT THE SAME TIME THIS
FLOW WILL TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE
ADVECTED NORTHWARD LATE IN THE WEEK. THE MODELS CONTINUE TO
EXHIBIT DISCREPANCIES WITH RESPECT TO THE TRAJECTORY OF THIS
MOISTURE SURGE...WITH THE GFS CONSISTENTLY BEING THE FURTHER WEST
SOLUTION PULLING THIS PLUME INTO THE EASTERN HALF OF UT...WHILE
THE EC HAS BEEN TAKING THIS PLUME FURTHER EAST INTO CO. GIVEN
THESE VARIATIONS BETWEEN MODEL SOLUTIONS HAVE MAINTAINED GOING
20-30 PERCENT POPS ACROSS THE SOUTH AND EAST THURSDAY THROUGH
FRIDAY.

.LONG TERM (AFTER 06Z SATURDAY)...MEDIUM RANGE PERIOD BEGINS WITH
A DEEP UNSEASONABLY STRONG TROUGH MOVING THROUGH THE GREAT BASIN.
FRIDAY NIGHT A STRONG BAROCLINIC IS SITUATED JUST WEST OF UTAH.
VERY STRONG MID LEVEL FLOW IS EXPECTED AHEAD OF THIS BAROCLINIC
ZONE WITH THE GFS AND ECMWF EACH INDICATING 40-50 KTS OF SW FLOW
OVER WRN UT. THIS COMBINED WITH A TIGHTENING PRESSURE GRADIENT
WILL KEEP BREEZY TO WINDY CONDITIONS GOING THROUGH THE NIGHT IN
MANY AREAS ACROSS WRN UT. THIS WILL ALSO KEEP MIN TEMPERATURES
ELEVATED THAT NIGHT AND HAVE INCREASED THE MORNING LOWS FOR
SATURDAY A BIT TO REFLECT THIS.

THE WINDY CONDITIONS WILL CONTINUE INTO THE DAY SATURDAY BEFORE THE
STRONG COLD FRONT SWEEPS THROUGH THE AREA BRINGING A SIGNIFICANT
TEMPERATURE DROP AND BREEZY WEST-NORTHWEST WINDS. ANTICIPATE THAT
THERE WILL BE A BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH
THE FRONTAL BOUNDARY...PARTICULARLY ACROSS CENTRAL AND NRN UT.
WITH 700 HPA TEMPS DROPPING TO -1 TO -2C SHOULD EVEN SEE A BIT OF
LIGHT SNOW IN THE HIGH UINTAS.

THE ECMWF...GFS...AND CANADIAN ARE NOW IN AGREEMENT THAT THE TROUGH
IS VERY PROGRESSIVE AND THE FLOW WILL QUICKLY BACK TO THE SOUTH BY
SUNDAY NIGHT. STILL MUCH COOLER AIR WILL RESIDE ACROSS CENTRAL AND
NRN UT AND SUNDAY HIGH TEMPERATURES WILL GENERALLY BE 10F COOLER
THAN SATURDAY/S AND 15-20F THAN FRIDAY/S...AT LEAST ACROSS NRN UT.
FOR THE START OF NEXT WEEK A BAGGY TROUGH LINGERS OVER THE WESTERN
U.S. LEADING TO A SLOW REBOUND TO NEAR NORMAL TEMPERATURES.

&&

.AVIATION...GUSTY SOUTHERLY WINDS ARE EXPECTED TO CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE TAF PERIOD...WITH ONLY A 10
PERCENT CHANCE THAT A LAKE BREEZE COULD PUSH WINDS TO THE WEST-
NORTHWEST BETWEEN 23Z AND 01Z. THERE IS ALSO A 10 PERCENT CHANCE
THAT A SHOWER COULD IMPACT THE TERMINAL THROUGH 03Z...WITH BRIEF
GUSTY ERRATIC WINDS AS THE MOST LIKELY IMPACT.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS
THE WESTERN HALF OF THE AREA THURSDAY INTO FRIDAY. IN ADDITION TO
THE GUSTY WINDS...HUMIDITY VALUES ARE EXPECTED TO FALL BELOW 15
PERCENT EACH AFTERNOON WITH POOR OVERNIGHT RECOVERIES. FURTHER
EAST MOISTURE IS EXPECTED TO INCREASE ACROSS THE EASTERN HALF OF
UTAH THURSDAY INTO FRIDAY BRINGING A RETURN OF SHOWERS AND
THUNDERSTORMS. THIS UPSTREAM TROUGH IS FORECAST TO SWING THROUGH
THE REGION SATURDAY BRINGING A CHANCE FOR PRECIPITATION TO
NORTHERN AND CENTRAL UTAH. WINDS WILL ALSO REMAIN ELEVATED
ACROSS MOST VALLEYS THROUGH THE DAY SATURDAY. A MUCH COOLER
AIRMASS WILL FOLLOW THIS SYSTEM FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN/GRAHAM/SCHOENING

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 022153
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
353 PM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (THROUGH 06Z SATURDAY)...SOUTHWESTERLY FLOW ALOFT
PREVAILS ACROSS THE GREAT BASIN THIS AFTERNOON...DOWNSTREAM FROM A
MID LEVEL TROUGH SITUATED ALONG THE WEST COAST. THIS FLOW HAS
GRADUALLY DRIED THE AIRMASS ACROSS THE FORECAST AREA OVER THE PAST
COUPLE OF DAYS...RESULTING IN VERY SHALLOW CU DEVELOPMENT ACROSS
THE HIGHER TERRAIN OF SOUTHERN UT...AND ONLY VERY ISOLATED SHOWERS
ACROSS THE NORTH. HAVE MAINTAINED SLIGHT CHANCE WITHIN A
RELATIVELY NARROW AXIS OF MID LEVEL MOISTURE ACROSS NORTHWEST UT
THIS EVENING.

THE WEST COAST TROUGH IS FORECAST TO SLOWLY DEEPEN THROUGH THE
SHORT TERM PERIOD...STRENGTHENING THE FLOW DOWNSTREAM ACROSS THE
EASTERN GREAT BASIN AND RESULTING IN BREEZY TO WINDY CONDITIONS
ACROSS WESTERN UT BOTH THURSDAY AND FRIDAY. AT THE SAME TIME THIS
FLOW WILL TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE
ADVECTED NORTHWARD LATE IN THE WEEK. THE MODELS CONTINUE TO
EXHIBIT DISCREPANCIES WITH RESPECT TO THE TRAJECTORY OF THIS
MOISTURE SURGE...WITH THE GFS CONSISTENTLY BEING THE FURTHER WEST
SOLUTION PULLING THIS PLUME INTO THE EASTERN HALF OF UT...WHILE
THE EC HAS BEEN TAKING THIS PLUME FURTHER EAST INTO CO. GIVEN
THESE VARIATIONS BETWEEN MODEL SOLUTIONS HAVE MAINTAINED GOING
20-30 PERCENT POPS ACROSS THE SOUTH AND EAST THURSDAY THROUGH
FRIDAY.

.LONG TERM (AFTER 06Z SATURDAY)...MEDIUM RANGE PERIOD BEGINS WITH
A DEEP UNSEASONABLY STRONG TROUGH MOVING THROUGH THE GREAT BASIN.
FRIDAY NIGHT A STRONG BAROCLINIC IS SITUATED JUST WEST OF UTAH.
VERY STRONG MID LEVEL FLOW IS EXPECTED AHEAD OF THIS BAROCLINIC
ZONE WITH THE GFS AND ECMWF EACH INDICATING 40-50 KTS OF SW FLOW
OVER WRN UT. THIS COMBINED WITH A TIGHTENING PRESSURE GRADIENT
WILL KEEP BREEZY TO WINDY CONDITIONS GOING THROUGH THE NIGHT IN
MANY AREAS ACROSS WRN UT. THIS WILL ALSO KEEP MIN TEMPERATURES
ELEVATED THAT NIGHT AND HAVE INCREASED THE MORNING LOWS FOR
SATURDAY A BIT TO REFLECT THIS.

THE WINDY CONDITIONS WILL CONTINUE INTO THE DAY SATURDAY BEFORE THE
STRONG COLD FRONT SWEEPS THROUGH THE AREA BRINGING A SIGNIFICANT
TEMPERATURE DROP AND BREEZY WEST-NORTHWEST WINDS. ANTICIPATE THAT
THERE WILL BE A BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH
THE FRONTAL BOUNDARY...PARTICULARLY ACROSS CENTRAL AND NRN UT.
WITH 700 HPA TEMPS DROPPING TO -1 TO -2C SHOULD EVEN SEE A BIT OF
LIGHT SNOW IN THE HIGH UINTAS.

THE ECMWF...GFS...AND CANADIAN ARE NOW IN AGREEMENT THAT THE TROUGH
IS VERY PROGRESSIVE AND THE FLOW WILL QUICKLY BACK TO THE SOUTH BY
SUNDAY NIGHT. STILL MUCH COOLER AIR WILL RESIDE ACROSS CENTRAL AND
NRN UT AND SUNDAY HIGH TEMPERATURES WILL GENERALLY BE 10F COOLER
THAN SATURDAY/S AND 15-20F THAN FRIDAY/S...AT LEAST ACROSS NRN UT.
FOR THE START OF NEXT WEEK A BAGGY TROUGH LINGERS OVER THE WESTERN
U.S. LEADING TO A SLOW REBOUND TO NEAR NORMAL TEMPERATURES.

&&

.AVIATION...GUSTY SOUTHERLY WINDS ARE EXPECTED TO CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE TAF PERIOD...WITH ONLY A 10
PERCENT CHANCE THAT A LAKE BREEZE COULD PUSH WINDS TO THE WEST-
NORTHWEST BETWEEN 23Z AND 01Z. THERE IS ALSO A 10 PERCENT CHANCE
THAT A SHOWER COULD IMPACT THE TERMINAL THROUGH 03Z...WITH BRIEF
GUSTY ERRATIC WINDS AS THE MOST LIKELY IMPACT.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS
THE WESTERN HALF OF THE AREA THURSDAY INTO FRIDAY. IN ADDITION TO
THE GUSTY WINDS...HUMIDITY VALUES ARE EXPECTED TO FALL BELOW 15
PERCENT EACH AFTERNOON WITH POOR OVERNIGHT RECOVERIES. FURTHER
EAST MOISTURE IS EXPECTED TO INCREASE ACROSS THE EASTERN HALF OF
UTAH THURSDAY INTO FRIDAY BRINGING A RETURN OF SHOWERS AND
THUNDERSTORMS. THIS UPSTREAM TROUGH IS FORECAST TO SWING THROUGH
THE REGION SATURDAY BRINGING A CHANCE FOR PRECIPITATION TO
NORTHERN AND CENTRAL UTAH. WINDS WILL ALSO REMAIN ELEVATED
ACROSS MOST VALLEYS THROUGH THE DAY SATURDAY. A MUCH COOLER
AIRMASS WILL FOLLOW THIS SYSTEM FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN/GRAHAM/SCHOENING

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 022153
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
353 PM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (THROUGH 06Z SATURDAY)...SOUTHWESTERLY FLOW ALOFT
PREVAILS ACROSS THE GREAT BASIN THIS AFTERNOON...DOWNSTREAM FROM A
MID LEVEL TROUGH SITUATED ALONG THE WEST COAST. THIS FLOW HAS
GRADUALLY DRIED THE AIRMASS ACROSS THE FORECAST AREA OVER THE PAST
COUPLE OF DAYS...RESULTING IN VERY SHALLOW CU DEVELOPMENT ACROSS
THE HIGHER TERRAIN OF SOUTHERN UT...AND ONLY VERY ISOLATED SHOWERS
ACROSS THE NORTH. HAVE MAINTAINED SLIGHT CHANCE WITHIN A
RELATIVELY NARROW AXIS OF MID LEVEL MOISTURE ACROSS NORTHWEST UT
THIS EVENING.

THE WEST COAST TROUGH IS FORECAST TO SLOWLY DEEPEN THROUGH THE
SHORT TERM PERIOD...STRENGTHENING THE FLOW DOWNSTREAM ACROSS THE
EASTERN GREAT BASIN AND RESULTING IN BREEZY TO WINDY CONDITIONS
ACROSS WESTERN UT BOTH THURSDAY AND FRIDAY. AT THE SAME TIME THIS
FLOW WILL TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE
ADVECTED NORTHWARD LATE IN THE WEEK. THE MODELS CONTINUE TO
EXHIBIT DISCREPANCIES WITH RESPECT TO THE TRAJECTORY OF THIS
MOISTURE SURGE...WITH THE GFS CONSISTENTLY BEING THE FURTHER WEST
SOLUTION PULLING THIS PLUME INTO THE EASTERN HALF OF UT...WHILE
THE EC HAS BEEN TAKING THIS PLUME FURTHER EAST INTO CO. GIVEN
THESE VARIATIONS BETWEEN MODEL SOLUTIONS HAVE MAINTAINED GOING
20-30 PERCENT POPS ACROSS THE SOUTH AND EAST THURSDAY THROUGH
FRIDAY.

.LONG TERM (AFTER 06Z SATURDAY)...MEDIUM RANGE PERIOD BEGINS WITH
A DEEP UNSEASONABLY STRONG TROUGH MOVING THROUGH THE GREAT BASIN.
FRIDAY NIGHT A STRONG BAROCLINIC IS SITUATED JUST WEST OF UTAH.
VERY STRONG MID LEVEL FLOW IS EXPECTED AHEAD OF THIS BAROCLINIC
ZONE WITH THE GFS AND ECMWF EACH INDICATING 40-50 KTS OF SW FLOW
OVER WRN UT. THIS COMBINED WITH A TIGHTENING PRESSURE GRADIENT
WILL KEEP BREEZY TO WINDY CONDITIONS GOING THROUGH THE NIGHT IN
MANY AREAS ACROSS WRN UT. THIS WILL ALSO KEEP MIN TEMPERATURES
ELEVATED THAT NIGHT AND HAVE INCREASED THE MORNING LOWS FOR
SATURDAY A BIT TO REFLECT THIS.

THE WINDY CONDITIONS WILL CONTINUE INTO THE DAY SATURDAY BEFORE THE
STRONG COLD FRONT SWEEPS THROUGH THE AREA BRINGING A SIGNIFICANT
TEMPERATURE DROP AND BREEZY WEST-NORTHWEST WINDS. ANTICIPATE THAT
THERE WILL BE A BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH
THE FRONTAL BOUNDARY...PARTICULARLY ACROSS CENTRAL AND NRN UT.
WITH 700 HPA TEMPS DROPPING TO -1 TO -2C SHOULD EVEN SEE A BIT OF
LIGHT SNOW IN THE HIGH UINTAS.

THE ECMWF...GFS...AND CANADIAN ARE NOW IN AGREEMENT THAT THE TROUGH
IS VERY PROGRESSIVE AND THE FLOW WILL QUICKLY BACK TO THE SOUTH BY
SUNDAY NIGHT. STILL MUCH COOLER AIR WILL RESIDE ACROSS CENTRAL AND
NRN UT AND SUNDAY HIGH TEMPERATURES WILL GENERALLY BE 10F COOLER
THAN SATURDAY/S AND 15-20F THAN FRIDAY/S...AT LEAST ACROSS NRN UT.
FOR THE START OF NEXT WEEK A BAGGY TROUGH LINGERS OVER THE WESTERN
U.S. LEADING TO A SLOW REBOUND TO NEAR NORMAL TEMPERATURES.

&&

.AVIATION...GUSTY SOUTHERLY WINDS ARE EXPECTED TO CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE TAF PERIOD...WITH ONLY A 10
PERCENT CHANCE THAT A LAKE BREEZE COULD PUSH WINDS TO THE WEST-
NORTHWEST BETWEEN 23Z AND 01Z. THERE IS ALSO A 10 PERCENT CHANCE
THAT A SHOWER COULD IMPACT THE TERMINAL THROUGH 03Z...WITH BRIEF
GUSTY ERRATIC WINDS AS THE MOST LIKELY IMPACT.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS
THE WESTERN HALF OF THE AREA THURSDAY INTO FRIDAY. IN ADDITION TO
THE GUSTY WINDS...HUMIDITY VALUES ARE EXPECTED TO FALL BELOW 15
PERCENT EACH AFTERNOON WITH POOR OVERNIGHT RECOVERIES. FURTHER
EAST MOISTURE IS EXPECTED TO INCREASE ACROSS THE EASTERN HALF OF
UTAH THURSDAY INTO FRIDAY BRINGING A RETURN OF SHOWERS AND
THUNDERSTORMS. THIS UPSTREAM TROUGH IS FORECAST TO SWING THROUGH
THE REGION SATURDAY BRINGING A CHANCE FOR PRECIPITATION TO
NORTHERN AND CENTRAL UTAH. WINDS WILL ALSO REMAIN ELEVATED
ACROSS MOST VALLEYS THROUGH THE DAY SATURDAY. A MUCH COOLER
AIRMASS WILL FOLLOW THIS SYSTEM FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN/GRAHAM/SCHOENING

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 022153
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
353 PM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (THROUGH 06Z SATURDAY)...SOUTHWESTERLY FLOW ALOFT
PREVAILS ACROSS THE GREAT BASIN THIS AFTERNOON...DOWNSTREAM FROM A
MID LEVEL TROUGH SITUATED ALONG THE WEST COAST. THIS FLOW HAS
GRADUALLY DRIED THE AIRMASS ACROSS THE FORECAST AREA OVER THE PAST
COUPLE OF DAYS...RESULTING IN VERY SHALLOW CU DEVELOPMENT ACROSS
THE HIGHER TERRAIN OF SOUTHERN UT...AND ONLY VERY ISOLATED SHOWERS
ACROSS THE NORTH. HAVE MAINTAINED SLIGHT CHANCE WITHIN A
RELATIVELY NARROW AXIS OF MID LEVEL MOISTURE ACROSS NORTHWEST UT
THIS EVENING.

THE WEST COAST TROUGH IS FORECAST TO SLOWLY DEEPEN THROUGH THE
SHORT TERM PERIOD...STRENGTHENING THE FLOW DOWNSTREAM ACROSS THE
EASTERN GREAT BASIN AND RESULTING IN BREEZY TO WINDY CONDITIONS
ACROSS WESTERN UT BOTH THURSDAY AND FRIDAY. AT THE SAME TIME THIS
FLOW WILL TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE
ADVECTED NORTHWARD LATE IN THE WEEK. THE MODELS CONTINUE TO
EXHIBIT DISCREPANCIES WITH RESPECT TO THE TRAJECTORY OF THIS
MOISTURE SURGE...WITH THE GFS CONSISTENTLY BEING THE FURTHER WEST
SOLUTION PULLING THIS PLUME INTO THE EASTERN HALF OF UT...WHILE
THE EC HAS BEEN TAKING THIS PLUME FURTHER EAST INTO CO. GIVEN
THESE VARIATIONS BETWEEN MODEL SOLUTIONS HAVE MAINTAINED GOING
20-30 PERCENT POPS ACROSS THE SOUTH AND EAST THURSDAY THROUGH
FRIDAY.

.LONG TERM (AFTER 06Z SATURDAY)...MEDIUM RANGE PERIOD BEGINS WITH
A DEEP UNSEASONABLY STRONG TROUGH MOVING THROUGH THE GREAT BASIN.
FRIDAY NIGHT A STRONG BAROCLINIC IS SITUATED JUST WEST OF UTAH.
VERY STRONG MID LEVEL FLOW IS EXPECTED AHEAD OF THIS BAROCLINIC
ZONE WITH THE GFS AND ECMWF EACH INDICATING 40-50 KTS OF SW FLOW
OVER WRN UT. THIS COMBINED WITH A TIGHTENING PRESSURE GRADIENT
WILL KEEP BREEZY TO WINDY CONDITIONS GOING THROUGH THE NIGHT IN
MANY AREAS ACROSS WRN UT. THIS WILL ALSO KEEP MIN TEMPERATURES
ELEVATED THAT NIGHT AND HAVE INCREASED THE MORNING LOWS FOR
SATURDAY A BIT TO REFLECT THIS.

THE WINDY CONDITIONS WILL CONTINUE INTO THE DAY SATURDAY BEFORE THE
STRONG COLD FRONT SWEEPS THROUGH THE AREA BRINGING A SIGNIFICANT
TEMPERATURE DROP AND BREEZY WEST-NORTHWEST WINDS. ANTICIPATE THAT
THERE WILL BE A BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH
THE FRONTAL BOUNDARY...PARTICULARLY ACROSS CENTRAL AND NRN UT.
WITH 700 HPA TEMPS DROPPING TO -1 TO -2C SHOULD EVEN SEE A BIT OF
LIGHT SNOW IN THE HIGH UINTAS.

THE ECMWF...GFS...AND CANADIAN ARE NOW IN AGREEMENT THAT THE TROUGH
IS VERY PROGRESSIVE AND THE FLOW WILL QUICKLY BACK TO THE SOUTH BY
SUNDAY NIGHT. STILL MUCH COOLER AIR WILL RESIDE ACROSS CENTRAL AND
NRN UT AND SUNDAY HIGH TEMPERATURES WILL GENERALLY BE 10F COOLER
THAN SATURDAY/S AND 15-20F THAN FRIDAY/S...AT LEAST ACROSS NRN UT.
FOR THE START OF NEXT WEEK A BAGGY TROUGH LINGERS OVER THE WESTERN
U.S. LEADING TO A SLOW REBOUND TO NEAR NORMAL TEMPERATURES.

&&

.AVIATION...GUSTY SOUTHERLY WINDS ARE EXPECTED TO CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE TAF PERIOD...WITH ONLY A 10
PERCENT CHANCE THAT A LAKE BREEZE COULD PUSH WINDS TO THE WEST-
NORTHWEST BETWEEN 23Z AND 01Z. THERE IS ALSO A 10 PERCENT CHANCE
THAT A SHOWER COULD IMPACT THE TERMINAL THROUGH 03Z...WITH BRIEF
GUSTY ERRATIC WINDS AS THE MOST LIKELY IMPACT.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS
THE WESTERN HALF OF THE AREA THURSDAY INTO FRIDAY. IN ADDITION TO
THE GUSTY WINDS...HUMIDITY VALUES ARE EXPECTED TO FALL BELOW 15
PERCENT EACH AFTERNOON WITH POOR OVERNIGHT RECOVERIES. FURTHER
EAST MOISTURE IS EXPECTED TO INCREASE ACROSS THE EASTERN HALF OF
UTAH THURSDAY INTO FRIDAY BRINGING A RETURN OF SHOWERS AND
THUNDERSTORMS. THIS UPSTREAM TROUGH IS FORECAST TO SWING THROUGH
THE REGION SATURDAY BRINGING A CHANCE FOR PRECIPITATION TO
NORTHERN AND CENTRAL UTAH. WINDS WILL ALSO REMAIN ELEVATED
ACROSS MOST VALLEYS THROUGH THE DAY SATURDAY. A MUCH COOLER
AIRMASS WILL FOLLOW THIS SYSTEM FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN/GRAHAM/SCHOENING

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 021639
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1039 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
FORECAST AREA TODAY...DOWNSTREAM FROM A DEEPENING UPPER TROUGH
ALONG THE WEST COAST. ONCE AGAIN BREEZY SOUTHERLY WINDS ARE
EXPECTED ACROSS THE WESTERN VALLEYS THIS AFTERNOON AS HIGHER
MOMENTUM MIXES DOWN TO THE SURFACE. GOES PW IMAGERY AND 12Z
SOUNDINGS INDICATE THE AIRMASS HAS DRIED SLIGHTLY OVER THE LAST 24
HOURS...HOWEVER LINGERING MOISTURE WILL LIKELY ALLOW FOR AT LEAST
ISOLATED CONVECTION OVER THE HIGHER TERRAIN THIS
AFTERNOON...BEFORE WORKING ITS WAY OFF THE TERRAIN AND INTO THE
EASTERN VALLEYS. AN ISOLATED HEAVY RAINER OR TWO IS POSSIBLE...AND
UPDATED THE FORECAST TO INCLUDE SLIGHT CHANCE POPS ACROSS THE
EASTERN VALLEYS DURING THE AFTERNOON HOURS.

OF ADDITIONAL NOTE IS A PLUME OF MID LEVEL MOISTURE WORKING ITS
WAY NORTHWARD ACROSS EASTERN NV AND WEST CENTRAL UT. THIS MAY
PROVE SUFFICIENT FOR HIGH BASED CONVECTION ACROSS EASTERN NV THIS
AFTERNOON...EVENTUALLY SPREADING INTO NORTHWEST UT THIS EVENING.
GIVEN THE DEEPLY MIXED BOUNDARY LAYER IN PLACE GUSTY MICROBURST
WINDS WOULD BE THE MAIN THREAT WITH THIS ACTIVITY.

AS THIS TROUGH DEEPENS THURSDAY INTO FRIDAY SOUTHWESTERLY FLOW
WILL CONTINUE TO GRADUALLY INCREASE ACROSS WESTERN UT...RESULTING
IN BREEZY TO LOCALLY WINDY CONDITIONS. ADDITIONALLY THIS FLOW WILL
TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE ADVECTED
NORTHWARD LATE IN THE WEEK. THE MODELS HAVE STRUGGLED WITH RESPECT
TO THE TIMING AND TRAJECTORY OF THIS MOISTURE SURGE...HOWEVER IT
APPEARS MOISTURE SHOULD REACH AT LEAST SOUTHEAST UT LATE IN THE
DAY THURSDAY...AND REMAIN IN PLACE ACROSS THE EASTERN HALF OF UTAH
THROUGH FRIDAY.

THE UPSTREAM TROUGH IS FORECAST TO EJECT ACROSS THE NORTHERN GREAT
BASIN SATURDAY BRINGING A BETTER CHANCE FOR PRECIPITATION TO
NORTHERN UT. A MUCH COOLER AIRMASS WILL FOLLOW IN THE WAKE OF THIS
TROUGH FOR SUNDAY...WITH MAX TEMPERATURES STRUGGLING TO REACH THE
70F MARK ALONG THE WASATCH FRONT.

&&

.AVIATION...GUSTY SOUTHERLY WILL PREVAIL AT KSLC THROUGH THE
DAY...WITH A 20 PERCENT CHANCE OF A SWITCH TO THE NORTHWEST DURING
THE 22-01Z TIMEFRAME. THERE IS ALSO A 10 PERCENT CHANCE FOR A
STRAY SHOWER OR THUNDERSTORM WITH GUSTY ERRATIC WINDS DURING THE
22-04Z TIMEFRAME.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO LOCALLY WINDY
CONDITIONS ACROSS THE WESTERN HALF OF THE AREA...AND MAY RESULT IN
CRITICAL FIRE WEATHER CONDITIONS SHOULD FUELS BECOME SUFFICIENTLY
DRY. ADDITIONALLY...MOISTURE WITHIN THIS FLOW IS EXPECTED TO
INCREASE ACROSS THE EASTERN HALF OF UTAH THURSDAY INTO FRIDAY
BRINGING A RETURN OF SHOWERS AND THUNDERSTORMS. THIS UPSTREAM
TROUGH IS FORECAST TO SWING THROUGH THE REGION SATURDAY BRINGING A
CHANCE FOR PRECIPITATION TO NORTHERN UTAH. A MUCH COOLER AIRMASS
WILL FOLLOW FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 021639
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1039 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
FORECAST AREA TODAY...DOWNSTREAM FROM A DEEPENING UPPER TROUGH
ALONG THE WEST COAST. ONCE AGAIN BREEZY SOUTHERLY WINDS ARE
EXPECTED ACROSS THE WESTERN VALLEYS THIS AFTERNOON AS HIGHER
MOMENTUM MIXES DOWN TO THE SURFACE. GOES PW IMAGERY AND 12Z
SOUNDINGS INDICATE THE AIRMASS HAS DRIED SLIGHTLY OVER THE LAST 24
HOURS...HOWEVER LINGERING MOISTURE WILL LIKELY ALLOW FOR AT LEAST
ISOLATED CONVECTION OVER THE HIGHER TERRAIN THIS
AFTERNOON...BEFORE WORKING ITS WAY OFF THE TERRAIN AND INTO THE
EASTERN VALLEYS. AN ISOLATED HEAVY RAINER OR TWO IS POSSIBLE...AND
UPDATED THE FORECAST TO INCLUDE SLIGHT CHANCE POPS ACROSS THE
EASTERN VALLEYS DURING THE AFTERNOON HOURS.

OF ADDITIONAL NOTE IS A PLUME OF MID LEVEL MOISTURE WORKING ITS
WAY NORTHWARD ACROSS EASTERN NV AND WEST CENTRAL UT. THIS MAY
PROVE SUFFICIENT FOR HIGH BASED CONVECTION ACROSS EASTERN NV THIS
AFTERNOON...EVENTUALLY SPREADING INTO NORTHWEST UT THIS EVENING.
GIVEN THE DEEPLY MIXED BOUNDARY LAYER IN PLACE GUSTY MICROBURST
WINDS WOULD BE THE MAIN THREAT WITH THIS ACTIVITY.

AS THIS TROUGH DEEPENS THURSDAY INTO FRIDAY SOUTHWESTERLY FLOW
WILL CONTINUE TO GRADUALLY INCREASE ACROSS WESTERN UT...RESULTING
IN BREEZY TO LOCALLY WINDY CONDITIONS. ADDITIONALLY THIS FLOW WILL
TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE ADVECTED
NORTHWARD LATE IN THE WEEK. THE MODELS HAVE STRUGGLED WITH RESPECT
TO THE TIMING AND TRAJECTORY OF THIS MOISTURE SURGE...HOWEVER IT
APPEARS MOISTURE SHOULD REACH AT LEAST SOUTHEAST UT LATE IN THE
DAY THURSDAY...AND REMAIN IN PLACE ACROSS THE EASTERN HALF OF UTAH
THROUGH FRIDAY.

THE UPSTREAM TROUGH IS FORECAST TO EJECT ACROSS THE NORTHERN GREAT
BASIN SATURDAY BRINGING A BETTER CHANCE FOR PRECIPITATION TO
NORTHERN UT. A MUCH COOLER AIRMASS WILL FOLLOW IN THE WAKE OF THIS
TROUGH FOR SUNDAY...WITH MAX TEMPERATURES STRUGGLING TO REACH THE
70F MARK ALONG THE WASATCH FRONT.

&&

.AVIATION...GUSTY SOUTHERLY WILL PREVAIL AT KSLC THROUGH THE
DAY...WITH A 20 PERCENT CHANCE OF A SWITCH TO THE NORTHWEST DURING
THE 22-01Z TIMEFRAME. THERE IS ALSO A 10 PERCENT CHANCE FOR A
STRAY SHOWER OR THUNDERSTORM WITH GUSTY ERRATIC WINDS DURING THE
22-04Z TIMEFRAME.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO LOCALLY WINDY
CONDITIONS ACROSS THE WESTERN HALF OF THE AREA...AND MAY RESULT IN
CRITICAL FIRE WEATHER CONDITIONS SHOULD FUELS BECOME SUFFICIENTLY
DRY. ADDITIONALLY...MOISTURE WITHIN THIS FLOW IS EXPECTED TO
INCREASE ACROSS THE EASTERN HALF OF UTAH THURSDAY INTO FRIDAY
BRINGING A RETURN OF SHOWERS AND THUNDERSTORMS. THIS UPSTREAM
TROUGH IS FORECAST TO SWING THROUGH THE REGION SATURDAY BRINGING A
CHANCE FOR PRECIPITATION TO NORTHERN UTAH. A MUCH COOLER AIRMASS
WILL FOLLOW FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 021639
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1039 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
FORECAST AREA TODAY...DOWNSTREAM FROM A DEEPENING UPPER TROUGH
ALONG THE WEST COAST. ONCE AGAIN BREEZY SOUTHERLY WINDS ARE
EXPECTED ACROSS THE WESTERN VALLEYS THIS AFTERNOON AS HIGHER
MOMENTUM MIXES DOWN TO THE SURFACE. GOES PW IMAGERY AND 12Z
SOUNDINGS INDICATE THE AIRMASS HAS DRIED SLIGHTLY OVER THE LAST 24
HOURS...HOWEVER LINGERING MOISTURE WILL LIKELY ALLOW FOR AT LEAST
ISOLATED CONVECTION OVER THE HIGHER TERRAIN THIS
AFTERNOON...BEFORE WORKING ITS WAY OFF THE TERRAIN AND INTO THE
EASTERN VALLEYS. AN ISOLATED HEAVY RAINER OR TWO IS POSSIBLE...AND
UPDATED THE FORECAST TO INCLUDE SLIGHT CHANCE POPS ACROSS THE
EASTERN VALLEYS DURING THE AFTERNOON HOURS.

OF ADDITIONAL NOTE IS A PLUME OF MID LEVEL MOISTURE WORKING ITS
WAY NORTHWARD ACROSS EASTERN NV AND WEST CENTRAL UT. THIS MAY
PROVE SUFFICIENT FOR HIGH BASED CONVECTION ACROSS EASTERN NV THIS
AFTERNOON...EVENTUALLY SPREADING INTO NORTHWEST UT THIS EVENING.
GIVEN THE DEEPLY MIXED BOUNDARY LAYER IN PLACE GUSTY MICROBURST
WINDS WOULD BE THE MAIN THREAT WITH THIS ACTIVITY.

AS THIS TROUGH DEEPENS THURSDAY INTO FRIDAY SOUTHWESTERLY FLOW
WILL CONTINUE TO GRADUALLY INCREASE ACROSS WESTERN UT...RESULTING
IN BREEZY TO LOCALLY WINDY CONDITIONS. ADDITIONALLY THIS FLOW WILL
TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE ADVECTED
NORTHWARD LATE IN THE WEEK. THE MODELS HAVE STRUGGLED WITH RESPECT
TO THE TIMING AND TRAJECTORY OF THIS MOISTURE SURGE...HOWEVER IT
APPEARS MOISTURE SHOULD REACH AT LEAST SOUTHEAST UT LATE IN THE
DAY THURSDAY...AND REMAIN IN PLACE ACROSS THE EASTERN HALF OF UTAH
THROUGH FRIDAY.

THE UPSTREAM TROUGH IS FORECAST TO EJECT ACROSS THE NORTHERN GREAT
BASIN SATURDAY BRINGING A BETTER CHANCE FOR PRECIPITATION TO
NORTHERN UT. A MUCH COOLER AIRMASS WILL FOLLOW IN THE WAKE OF THIS
TROUGH FOR SUNDAY...WITH MAX TEMPERATURES STRUGGLING TO REACH THE
70F MARK ALONG THE WASATCH FRONT.

&&

.AVIATION...GUSTY SOUTHERLY WILL PREVAIL AT KSLC THROUGH THE
DAY...WITH A 20 PERCENT CHANCE OF A SWITCH TO THE NORTHWEST DURING
THE 22-01Z TIMEFRAME. THERE IS ALSO A 10 PERCENT CHANCE FOR A
STRAY SHOWER OR THUNDERSTORM WITH GUSTY ERRATIC WINDS DURING THE
22-04Z TIMEFRAME.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO LOCALLY WINDY
CONDITIONS ACROSS THE WESTERN HALF OF THE AREA...AND MAY RESULT IN
CRITICAL FIRE WEATHER CONDITIONS SHOULD FUELS BECOME SUFFICIENTLY
DRY. ADDITIONALLY...MOISTURE WITHIN THIS FLOW IS EXPECTED TO
INCREASE ACROSS THE EASTERN HALF OF UTAH THURSDAY INTO FRIDAY
BRINGING A RETURN OF SHOWERS AND THUNDERSTORMS. THIS UPSTREAM
TROUGH IS FORECAST TO SWING THROUGH THE REGION SATURDAY BRINGING A
CHANCE FOR PRECIPITATION TO NORTHERN UTAH. A MUCH COOLER AIRMASS
WILL FOLLOW FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 021639
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1039 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
FORECAST AREA TODAY...DOWNSTREAM FROM A DEEPENING UPPER TROUGH
ALONG THE WEST COAST. ONCE AGAIN BREEZY SOUTHERLY WINDS ARE
EXPECTED ACROSS THE WESTERN VALLEYS THIS AFTERNOON AS HIGHER
MOMENTUM MIXES DOWN TO THE SURFACE. GOES PW IMAGERY AND 12Z
SOUNDINGS INDICATE THE AIRMASS HAS DRIED SLIGHTLY OVER THE LAST 24
HOURS...HOWEVER LINGERING MOISTURE WILL LIKELY ALLOW FOR AT LEAST
ISOLATED CONVECTION OVER THE HIGHER TERRAIN THIS
AFTERNOON...BEFORE WORKING ITS WAY OFF THE TERRAIN AND INTO THE
EASTERN VALLEYS. AN ISOLATED HEAVY RAINER OR TWO IS POSSIBLE...AND
UPDATED THE FORECAST TO INCLUDE SLIGHT CHANCE POPS ACROSS THE
EASTERN VALLEYS DURING THE AFTERNOON HOURS.

OF ADDITIONAL NOTE IS A PLUME OF MID LEVEL MOISTURE WORKING ITS
WAY NORTHWARD ACROSS EASTERN NV AND WEST CENTRAL UT. THIS MAY
PROVE SUFFICIENT FOR HIGH BASED CONVECTION ACROSS EASTERN NV THIS
AFTERNOON...EVENTUALLY SPREADING INTO NORTHWEST UT THIS EVENING.
GIVEN THE DEEPLY MIXED BOUNDARY LAYER IN PLACE GUSTY MICROBURST
WINDS WOULD BE THE MAIN THREAT WITH THIS ACTIVITY.

AS THIS TROUGH DEEPENS THURSDAY INTO FRIDAY SOUTHWESTERLY FLOW
WILL CONTINUE TO GRADUALLY INCREASE ACROSS WESTERN UT...RESULTING
IN BREEZY TO LOCALLY WINDY CONDITIONS. ADDITIONALLY THIS FLOW WILL
TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE ADVECTED
NORTHWARD LATE IN THE WEEK. THE MODELS HAVE STRUGGLED WITH RESPECT
TO THE TIMING AND TRAJECTORY OF THIS MOISTURE SURGE...HOWEVER IT
APPEARS MOISTURE SHOULD REACH AT LEAST SOUTHEAST UT LATE IN THE
DAY THURSDAY...AND REMAIN IN PLACE ACROSS THE EASTERN HALF OF UTAH
THROUGH FRIDAY.

THE UPSTREAM TROUGH IS FORECAST TO EJECT ACROSS THE NORTHERN GREAT
BASIN SATURDAY BRINGING A BETTER CHANCE FOR PRECIPITATION TO
NORTHERN UT. A MUCH COOLER AIRMASS WILL FOLLOW IN THE WAKE OF THIS
TROUGH FOR SUNDAY...WITH MAX TEMPERATURES STRUGGLING TO REACH THE
70F MARK ALONG THE WASATCH FRONT.

&&

.AVIATION...GUSTY SOUTHERLY WILL PREVAIL AT KSLC THROUGH THE
DAY...WITH A 20 PERCENT CHANCE OF A SWITCH TO THE NORTHWEST DURING
THE 22-01Z TIMEFRAME. THERE IS ALSO A 10 PERCENT CHANCE FOR A
STRAY SHOWER OR THUNDERSTORM WITH GUSTY ERRATIC WINDS DURING THE
22-04Z TIMEFRAME.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO LOCALLY WINDY
CONDITIONS ACROSS THE WESTERN HALF OF THE AREA...AND MAY RESULT IN
CRITICAL FIRE WEATHER CONDITIONS SHOULD FUELS BECOME SUFFICIENTLY
DRY. ADDITIONALLY...MOISTURE WITHIN THIS FLOW IS EXPECTED TO
INCREASE ACROSS THE EASTERN HALF OF UTAH THURSDAY INTO FRIDAY
BRINGING A RETURN OF SHOWERS AND THUNDERSTORMS. THIS UPSTREAM
TROUGH IS FORECAST TO SWING THROUGH THE REGION SATURDAY BRINGING A
CHANCE FOR PRECIPITATION TO NORTHERN UTAH. A MUCH COOLER AIRMASS
WILL FOLLOW FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 021639
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1039 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
FORECAST AREA TODAY...DOWNSTREAM FROM A DEEPENING UPPER TROUGH
ALONG THE WEST COAST. ONCE AGAIN BREEZY SOUTHERLY WINDS ARE
EXPECTED ACROSS THE WESTERN VALLEYS THIS AFTERNOON AS HIGHER
MOMENTUM MIXES DOWN TO THE SURFACE. GOES PW IMAGERY AND 12Z
SOUNDINGS INDICATE THE AIRMASS HAS DRIED SLIGHTLY OVER THE LAST 24
HOURS...HOWEVER LINGERING MOISTURE WILL LIKELY ALLOW FOR AT LEAST
ISOLATED CONVECTION OVER THE HIGHER TERRAIN THIS
AFTERNOON...BEFORE WORKING ITS WAY OFF THE TERRAIN AND INTO THE
EASTERN VALLEYS. AN ISOLATED HEAVY RAINER OR TWO IS POSSIBLE...AND
UPDATED THE FORECAST TO INCLUDE SLIGHT CHANCE POPS ACROSS THE
EASTERN VALLEYS DURING THE AFTERNOON HOURS.

OF ADDITIONAL NOTE IS A PLUME OF MID LEVEL MOISTURE WORKING ITS
WAY NORTHWARD ACROSS EASTERN NV AND WEST CENTRAL UT. THIS MAY
PROVE SUFFICIENT FOR HIGH BASED CONVECTION ACROSS EASTERN NV THIS
AFTERNOON...EVENTUALLY SPREADING INTO NORTHWEST UT THIS EVENING.
GIVEN THE DEEPLY MIXED BOUNDARY LAYER IN PLACE GUSTY MICROBURST
WINDS WOULD BE THE MAIN THREAT WITH THIS ACTIVITY.

AS THIS TROUGH DEEPENS THURSDAY INTO FRIDAY SOUTHWESTERLY FLOW
WILL CONTINUE TO GRADUALLY INCREASE ACROSS WESTERN UT...RESULTING
IN BREEZY TO LOCALLY WINDY CONDITIONS. ADDITIONALLY THIS FLOW WILL
TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE ADVECTED
NORTHWARD LATE IN THE WEEK. THE MODELS HAVE STRUGGLED WITH RESPECT
TO THE TIMING AND TRAJECTORY OF THIS MOISTURE SURGE...HOWEVER IT
APPEARS MOISTURE SHOULD REACH AT LEAST SOUTHEAST UT LATE IN THE
DAY THURSDAY...AND REMAIN IN PLACE ACROSS THE EASTERN HALF OF UTAH
THROUGH FRIDAY.

THE UPSTREAM TROUGH IS FORECAST TO EJECT ACROSS THE NORTHERN GREAT
BASIN SATURDAY BRINGING A BETTER CHANCE FOR PRECIPITATION TO
NORTHERN UT. A MUCH COOLER AIRMASS WILL FOLLOW IN THE WAKE OF THIS
TROUGH FOR SUNDAY...WITH MAX TEMPERATURES STRUGGLING TO REACH THE
70F MARK ALONG THE WASATCH FRONT.

&&

.AVIATION...GUSTY SOUTHERLY WILL PREVAIL AT KSLC THROUGH THE
DAY...WITH A 20 PERCENT CHANCE OF A SWITCH TO THE NORTHWEST DURING
THE 22-01Z TIMEFRAME. THERE IS ALSO A 10 PERCENT CHANCE FOR A
STRAY SHOWER OR THUNDERSTORM WITH GUSTY ERRATIC WINDS DURING THE
22-04Z TIMEFRAME.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO LOCALLY WINDY
CONDITIONS ACROSS THE WESTERN HALF OF THE AREA...AND MAY RESULT IN
CRITICAL FIRE WEATHER CONDITIONS SHOULD FUELS BECOME SUFFICIENTLY
DRY. ADDITIONALLY...MOISTURE WITHIN THIS FLOW IS EXPECTED TO
INCREASE ACROSS THE EASTERN HALF OF UTAH THURSDAY INTO FRIDAY
BRINGING A RETURN OF SHOWERS AND THUNDERSTORMS. THIS UPSTREAM
TROUGH IS FORECAST TO SWING THROUGH THE REGION SATURDAY BRINGING A
CHANCE FOR PRECIPITATION TO NORTHERN UTAH. A MUCH COOLER AIRMASS
WILL FOLLOW FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 021639
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1039 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. MILD
SOUTHWESTERLY FLOW WILL PREVAIL AHEAD OF THIS TROUGH THROUGH THE
REMAINDER OF THE WEEK...WITH COOL FALL LIKE TEMPERATURES ARRIVING
OVER THE LABOR DAY WEEKEND.

&&

.DISCUSSION...MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
FORECAST AREA TODAY...DOWNSTREAM FROM A DEEPENING UPPER TROUGH
ALONG THE WEST COAST. ONCE AGAIN BREEZY SOUTHERLY WINDS ARE
EXPECTED ACROSS THE WESTERN VALLEYS THIS AFTERNOON AS HIGHER
MOMENTUM MIXES DOWN TO THE SURFACE. GOES PW IMAGERY AND 12Z
SOUNDINGS INDICATE THE AIRMASS HAS DRIED SLIGHTLY OVER THE LAST 24
HOURS...HOWEVER LINGERING MOISTURE WILL LIKELY ALLOW FOR AT LEAST
ISOLATED CONVECTION OVER THE HIGHER TERRAIN THIS
AFTERNOON...BEFORE WORKING ITS WAY OFF THE TERRAIN AND INTO THE
EASTERN VALLEYS. AN ISOLATED HEAVY RAINER OR TWO IS POSSIBLE...AND
UPDATED THE FORECAST TO INCLUDE SLIGHT CHANCE POPS ACROSS THE
EASTERN VALLEYS DURING THE AFTERNOON HOURS.

OF ADDITIONAL NOTE IS A PLUME OF MID LEVEL MOISTURE WORKING ITS
WAY NORTHWARD ACROSS EASTERN NV AND WEST CENTRAL UT. THIS MAY
PROVE SUFFICIENT FOR HIGH BASED CONVECTION ACROSS EASTERN NV THIS
AFTERNOON...EVENTUALLY SPREADING INTO NORTHWEST UT THIS EVENING.
GIVEN THE DEEPLY MIXED BOUNDARY LAYER IN PLACE GUSTY MICROBURST
WINDS WOULD BE THE MAIN THREAT WITH THIS ACTIVITY.

AS THIS TROUGH DEEPENS THURSDAY INTO FRIDAY SOUTHWESTERLY FLOW
WILL CONTINUE TO GRADUALLY INCREASE ACROSS WESTERN UT...RESULTING
IN BREEZY TO LOCALLY WINDY CONDITIONS. ADDITIONALLY THIS FLOW WILL
TAP INTO DEEPER MOISTURE TO THE SOUTH...WHICH WILL BE ADVECTED
NORTHWARD LATE IN THE WEEK. THE MODELS HAVE STRUGGLED WITH RESPECT
TO THE TIMING AND TRAJECTORY OF THIS MOISTURE SURGE...HOWEVER IT
APPEARS MOISTURE SHOULD REACH AT LEAST SOUTHEAST UT LATE IN THE
DAY THURSDAY...AND REMAIN IN PLACE ACROSS THE EASTERN HALF OF UTAH
THROUGH FRIDAY.

THE UPSTREAM TROUGH IS FORECAST TO EJECT ACROSS THE NORTHERN GREAT
BASIN SATURDAY BRINGING A BETTER CHANCE FOR PRECIPITATION TO
NORTHERN UT. A MUCH COOLER AIRMASS WILL FOLLOW IN THE WAKE OF THIS
TROUGH FOR SUNDAY...WITH MAX TEMPERATURES STRUGGLING TO REACH THE
70F MARK ALONG THE WASATCH FRONT.

&&

.AVIATION...GUSTY SOUTHERLY WILL PREVAIL AT KSLC THROUGH THE
DAY...WITH A 20 PERCENT CHANCE OF A SWITCH TO THE NORTHWEST DURING
THE 22-01Z TIMEFRAME. THERE IS ALSO A 10 PERCENT CHANCE FOR A
STRAY SHOWER OR THUNDERSTORM WITH GUSTY ERRATIC WINDS DURING THE
22-04Z TIMEFRAME.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH THE REMAINDER
OF THE WEEK. THIS WILL RESULT IN BREEZY TO LOCALLY WINDY
CONDITIONS ACROSS THE WESTERN HALF OF THE AREA...AND MAY RESULT IN
CRITICAL FIRE WEATHER CONDITIONS SHOULD FUELS BECOME SUFFICIENTLY
DRY. ADDITIONALLY...MOISTURE WITHIN THIS FLOW IS EXPECTED TO
INCREASE ACROSS THE EASTERN HALF OF UTAH THURSDAY INTO FRIDAY
BRINGING A RETURN OF SHOWERS AND THUNDERSTORMS. THIS UPSTREAM
TROUGH IS FORECAST TO SWING THROUGH THE REGION SATURDAY BRINGING A
CHANCE FOR PRECIPITATION TO NORTHERN UTAH. A MUCH COOLER AIRMASS
WILL FOLLOW FOR SUNDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 021044
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
444 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. COOL FALL LIKE
TEMPERATURES ARE EXPECTED OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SUNDAY)...THE UPPER LOW CURRENTLY ALONG THE
BRITCOL COAST WILL CONTINUE ON A SLOW SOUTHWARD DRIFT INTO THE
PACIFIC NORTHWEST LATE IN THE WEEK. THE RESULTANT UNSEASONABLY
DEEP TROUGH ACROSS THE WEST COAST STATES WILL LEAVE THE GREAT
BASIN UNDER AN INCREASINGLY STRONG SOUTHWEST FLOW THROUGH THE
FIRST HALF OF THE UPCOMING WEEKEND.

THE INCREASING SOUTHWEST FLOW ALOFT COMBINED WITH THE SURFACE
TROUGH ALONG THE UTAH/NEVADA BORDER WILL RESULT IN STRONG
SOUTHERLY WINDS ACROSS THE WESTERN AND NORTHERN VALLEYS INTO THE
FIRST HALF OF THE WEEKEND. NOT ANTICIPATING ANY WIND HIGHLIGHTS
TODAY...BUT COULD SEE SOME ISSUES DEVELOP BY LATE THURSDAY AS THE
ADVANCING UPPER TROUGH NUDGES A FAIRLY STRONG COLD FRONT CLOSER TO
THE STATE. FRIDAY AND SATURDAY WILL SEE THE STRONGEST WINDS AS THE
COLD FRONT POSITIONS NEAR THE UTAH/NEVADA BORDER. AN HIGH WIND
EVENT COULD FORM IN THIS PATTERN AS NEAR 700 MB WINDS REACH 40
PLUS KNOTS AND THE THERMAL GRADIENT TIGHTENS IN ASSOCIATION WITH
THE SURFACE FRONT.

GOES IMAGERY STILL SHOWS HIGHER PWAT VALUES ACROSS ARIZONA AND
EXTREME SOUTHERN AND EASTERN UTAH. LOOKING AT A FEW THUNDERSTORMS
FORMING ALONG THE BOUNDARY BETWEEN THE MOISTURE PLUME AND THE
DRIER AIR TO THE WEST ACROSS SOUTH-CENTRAL THROUGH NORTHEAST UTAH
THIS AFTERNOON/EVENING. OVER NORTHERN UTAH AND AREA OF .60-.70
INCH PWAT VALUES MAY HELP FUEL CONVECTION LATER THIS AFTERNOON.
THE PAST COUPLE OF MODEL RUNS OF THE NAM/GFS HAVE INDICATED A BAND
OF PRECIP STRETCHED SOUTHWEST TO NORTHEAST ACROSS NORTHWEST UTAH
LATE THIS AFTERNOON AND EVENING. THIS BAND OF PRECIP APPEARS TO BE
CONCENTRATED NEAR THE SURFACE TROUGH AND UNDERNEATH AN AREA OF
UPPER DIVERGENCE ASSOCIATED WITH THE ENTRANCE REGION OF A MODEST
UPPER JET. SUSPECT THE QPF FIELDS ARE A BIT OVERDONE IN THE TWO
MODELS...BUT DO SEE THE POTENTIAL FOR AT LEAST ISOLATED CONVECTION
FORMING ACROSS THE NORTHWEST PER THE MODEL SOLUTION.

QUESTION FOR UPCOMING WEEKEND WILL BE HOW MUCH COOLING TO EXPECT
AND WHETHER ANY SIGNIFICANT PRECIP DEVELOPS WITH THE UPPER TROUGH
AND ASSOCIATED SURFACE FRONT. AT THIS POINT IT APPEARS THAT COOLER
FALL-LIKE TEMPS ARE A GIVEN BEHIND THE COLD FRONT ACROSS WEST-
CENTRAL THROUGH NORTHERN UTAH THIS WEEKEND. AS FAR AS PRECIP WOULD
EXPECTED CONVECTION TO FORM ALONG THE FRONTAL BOUNDARY AND THEN
EXTEND BACK INTO THE COLDER AIR TO THE NORTHWEST. CONVERGENCE INTO
THE SURFACE BOUNDARY SUPPORTED BY DYNAMIC LIFT FROM SHORTWAVES
EJECTING OUT AHEAD OF THE MAIN TROUGH WILL SUPPLY THE LIFT
NECESSARY FOR CONVECTIVE PRECIP ACROSS NORTHWEST UTAH. MOISTURE
WILL BE SOMEWHAT LIMITED...SO NOT ANTICIPATING ANY HEAVY PRECIP OR
STRONG THUNDERSTORMS AT THIS TIME THROUGH SATURDAY EVENING.

.LONG TERM (AFTER 06Z SUNDAY)...GLOBAL MODELS HAVE STARTED TO COME
INTO BETTER AGREEMENT WITH A FAIRLY STRONG...COLD PACIFIC TROUGH
EXPECTED TO CROSS THE NORTHERN INTERMOUNTAIN REGION/NORTHERN ROCKIES
SUNDAY. IN A FLIP FROM EARLIER RUNS...THE 00Z EC IS ACTUALLY A BIT
QUICKER WITH THIS SYSTEM. THE 00Z CANADIAN CONTINUED TO BE THE
SLOWEST MODEL...WITH THE SYSTEM CROSSING THE AREA LATER SUNDAY. THIS
SYSTEM IS ALSO QUITE A BIT DEEPER AS REPRESENTED IN THE CANADIAN.

IN GENERAL...A FAIRLY POTENT PACIFIC TROUGH IS EXPECTED TO CROSS THE
NORTHERN INTERMOUNTAIN/NORTHERN GREAT BASIN AREA DURING THE DAY
SUNDAY. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS
NORTHERN UTAH EARLY SUNDAY...REACHING AT LEAST CENTRAL UTAH BY
SUNDAY AFTERNOON BEFORE WEAKENING AS THE TROUGH ACCELERATES AWAY
FROM THE REGION. UNLIKE THE GFS RUNS OF THE PAST SEVERAL DAYS...THE
00Z RUN NOW DEPICTS 700MB TEMPERATURES FALLING TO NEAR -1C ALONG THE
UTAH/IDAHO BORDER BY 12Z SUNDAY. THIS MATCHES FAIRLY WELL WITH THE
00Z EC.

THE GLOBAL MODELS DIVERGE QUITE A BIT AFTER SUNDAY. THE GFS TAKES
THE SHORTWAVE DROPPING DOWN THE PACIFIC COAST IN THE WAKE OF THE
PREVIOUS SYSTEM AND DEVELOPS SOMEWHAT OF A CUT-OFF LOW OFF THE
CALIFORNIA COAST MONDAY. WITH THE LOW IN THIS POSITION...MOISTURE
SURGES INTO PORTIONS OF UTAH. MUCH OF THE REMAINDER OF THE GLOBAL
MODEL GUIDANCE VARIES SIGNIFICANTLY FROM THIS SOLUTION. FORECAST
PACKAGE ALREADY INCLUDED LOW END POPS ACROSS THE SOUTHERN MOUNTAINS.
LEFT THESE IN THE CURRENT PACKAGE GIVEN THE SIGNIFICANT VARIATION
BETWEEN THE GLOBAL MODELS. EVEN THESE LOW END POPS ARE TOO HIGH FOR
MOST OF THE GLOBAL GUIDANCE.

THE BIGGEST MESSAGE FOR THE LONG TERM PORTION OF THE FORECAST IS A
FAIRLY SIGNIFICANT COOL DOWN CAN BE EXPECTED SUNDAY ACROSS MUCH OF
THE STATE BEHIND THE FIRST REAL COLD FRONT OF THE APPROACHING FALL
SEASON...WITH TEMPERATURES FALLING 10-15 DEGREES FROM SATURDAYS
HIGHS. PORTIONS OF THE WASATCH FRONT MAY STRUGGLE TO EVEN REACH 70F
SUNDAY AFTERNOON.

&&

.FIRE WEATHER...A FAIRLY STRONG TROUGH WILL SLOWLY CROSS THE
NORTHWESTERN PORTION OF THE COUNTRY OVER THE NEXT SEVERAL DAYS.
AHEAD OF THIS SYSTEM...EXPECT GUSTY SOUTHERLY WINDS ACROSS MUCH OF
THE DISTRICT THROUGH AT LEAST SATURDAY. THE BEST CHANCE FOR
HUMIDITIES TO FALL BELOW CRITICAL LEVELS WILL BE ACROSS THE WEST
DESERTS THROUGH THIS PERIOD. LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE THROUGH SATURDAY IN LOCATIONS WITH
CRITICAL FUELS...ESPECIALLY ACROSS THE WESTERN DESERTS. AT THIS
TIME...THESE LOCATIONS DO NOT HAVE CRITICAL FUELS...SO HELD OFF ON
ANY FIRE WEATHER WATCHES OR RED FLAG WARNINGS.

A COLD FRONT WILL CROSS THE DISTRICT SUNDAY...BRINGING MUCH COOLER
TEMPERATURES AND A REDUCTION IN WINDS THROUGH AT LEAST EARLY NEXT
WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS WILL CONTINUE AT THE SLC TERMINAL
THROUGH THE DAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 021044
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
444 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. COOL FALL LIKE
TEMPERATURES ARE EXPECTED OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SUNDAY)...THE UPPER LOW CURRENTLY ALONG THE
BRITCOL COAST WILL CONTINUE ON A SLOW SOUTHWARD DRIFT INTO THE
PACIFIC NORTHWEST LATE IN THE WEEK. THE RESULTANT UNSEASONABLY
DEEP TROUGH ACROSS THE WEST COAST STATES WILL LEAVE THE GREAT
BASIN UNDER AN INCREASINGLY STRONG SOUTHWEST FLOW THROUGH THE
FIRST HALF OF THE UPCOMING WEEKEND.

THE INCREASING SOUTHWEST FLOW ALOFT COMBINED WITH THE SURFACE
TROUGH ALONG THE UTAH/NEVADA BORDER WILL RESULT IN STRONG
SOUTHERLY WINDS ACROSS THE WESTERN AND NORTHERN VALLEYS INTO THE
FIRST HALF OF THE WEEKEND. NOT ANTICIPATING ANY WIND HIGHLIGHTS
TODAY...BUT COULD SEE SOME ISSUES DEVELOP BY LATE THURSDAY AS THE
ADVANCING UPPER TROUGH NUDGES A FAIRLY STRONG COLD FRONT CLOSER TO
THE STATE. FRIDAY AND SATURDAY WILL SEE THE STRONGEST WINDS AS THE
COLD FRONT POSITIONS NEAR THE UTAH/NEVADA BORDER. AN HIGH WIND
EVENT COULD FORM IN THIS PATTERN AS NEAR 700 MB WINDS REACH 40
PLUS KNOTS AND THE THERMAL GRADIENT TIGHTENS IN ASSOCIATION WITH
THE SURFACE FRONT.

GOES IMAGERY STILL SHOWS HIGHER PWAT VALUES ACROSS ARIZONA AND
EXTREME SOUTHERN AND EASTERN UTAH. LOOKING AT A FEW THUNDERSTORMS
FORMING ALONG THE BOUNDARY BETWEEN THE MOISTURE PLUME AND THE
DRIER AIR TO THE WEST ACROSS SOUTH-CENTRAL THROUGH NORTHEAST UTAH
THIS AFTERNOON/EVENING. OVER NORTHERN UTAH AND AREA OF .60-.70
INCH PWAT VALUES MAY HELP FUEL CONVECTION LATER THIS AFTERNOON.
THE PAST COUPLE OF MODEL RUNS OF THE NAM/GFS HAVE INDICATED A BAND
OF PRECIP STRETCHED SOUTHWEST TO NORTHEAST ACROSS NORTHWEST UTAH
LATE THIS AFTERNOON AND EVENING. THIS BAND OF PRECIP APPEARS TO BE
CONCENTRATED NEAR THE SURFACE TROUGH AND UNDERNEATH AN AREA OF
UPPER DIVERGENCE ASSOCIATED WITH THE ENTRANCE REGION OF A MODEST
UPPER JET. SUSPECT THE QPF FIELDS ARE A BIT OVERDONE IN THE TWO
MODELS...BUT DO SEE THE POTENTIAL FOR AT LEAST ISOLATED CONVECTION
FORMING ACROSS THE NORTHWEST PER THE MODEL SOLUTION.

QUESTION FOR UPCOMING WEEKEND WILL BE HOW MUCH COOLING TO EXPECT
AND WHETHER ANY SIGNIFICANT PRECIP DEVELOPS WITH THE UPPER TROUGH
AND ASSOCIATED SURFACE FRONT. AT THIS POINT IT APPEARS THAT COOLER
FALL-LIKE TEMPS ARE A GIVEN BEHIND THE COLD FRONT ACROSS WEST-
CENTRAL THROUGH NORTHERN UTAH THIS WEEKEND. AS FAR AS PRECIP WOULD
EXPECTED CONVECTION TO FORM ALONG THE FRONTAL BOUNDARY AND THEN
EXTEND BACK INTO THE COLDER AIR TO THE NORTHWEST. CONVERGENCE INTO
THE SURFACE BOUNDARY SUPPORTED BY DYNAMIC LIFT FROM SHORTWAVES
EJECTING OUT AHEAD OF THE MAIN TROUGH WILL SUPPLY THE LIFT
NECESSARY FOR CONVECTIVE PRECIP ACROSS NORTHWEST UTAH. MOISTURE
WILL BE SOMEWHAT LIMITED...SO NOT ANTICIPATING ANY HEAVY PRECIP OR
STRONG THUNDERSTORMS AT THIS TIME THROUGH SATURDAY EVENING.

.LONG TERM (AFTER 06Z SUNDAY)...GLOBAL MODELS HAVE STARTED TO COME
INTO BETTER AGREEMENT WITH A FAIRLY STRONG...COLD PACIFIC TROUGH
EXPECTED TO CROSS THE NORTHERN INTERMOUNTAIN REGION/NORTHERN ROCKIES
SUNDAY. IN A FLIP FROM EARLIER RUNS...THE 00Z EC IS ACTUALLY A BIT
QUICKER WITH THIS SYSTEM. THE 00Z CANADIAN CONTINUED TO BE THE
SLOWEST MODEL...WITH THE SYSTEM CROSSING THE AREA LATER SUNDAY. THIS
SYSTEM IS ALSO QUITE A BIT DEEPER AS REPRESENTED IN THE CANADIAN.

IN GENERAL...A FAIRLY POTENT PACIFIC TROUGH IS EXPECTED TO CROSS THE
NORTHERN INTERMOUNTAIN/NORTHERN GREAT BASIN AREA DURING THE DAY
SUNDAY. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS
NORTHERN UTAH EARLY SUNDAY...REACHING AT LEAST CENTRAL UTAH BY
SUNDAY AFTERNOON BEFORE WEAKENING AS THE TROUGH ACCELERATES AWAY
FROM THE REGION. UNLIKE THE GFS RUNS OF THE PAST SEVERAL DAYS...THE
00Z RUN NOW DEPICTS 700MB TEMPERATURES FALLING TO NEAR -1C ALONG THE
UTAH/IDAHO BORDER BY 12Z SUNDAY. THIS MATCHES FAIRLY WELL WITH THE
00Z EC.

THE GLOBAL MODELS DIVERGE QUITE A BIT AFTER SUNDAY. THE GFS TAKES
THE SHORTWAVE DROPPING DOWN THE PACIFIC COAST IN THE WAKE OF THE
PREVIOUS SYSTEM AND DEVELOPS SOMEWHAT OF A CUT-OFF LOW OFF THE
CALIFORNIA COAST MONDAY. WITH THE LOW IN THIS POSITION...MOISTURE
SURGES INTO PORTIONS OF UTAH. MUCH OF THE REMAINDER OF THE GLOBAL
MODEL GUIDANCE VARIES SIGNIFICANTLY FROM THIS SOLUTION. FORECAST
PACKAGE ALREADY INCLUDED LOW END POPS ACROSS THE SOUTHERN MOUNTAINS.
LEFT THESE IN THE CURRENT PACKAGE GIVEN THE SIGNIFICANT VARIATION
BETWEEN THE GLOBAL MODELS. EVEN THESE LOW END POPS ARE TOO HIGH FOR
MOST OF THE GLOBAL GUIDANCE.

THE BIGGEST MESSAGE FOR THE LONG TERM PORTION OF THE FORECAST IS A
FAIRLY SIGNIFICANT COOL DOWN CAN BE EXPECTED SUNDAY ACROSS MUCH OF
THE STATE BEHIND THE FIRST REAL COLD FRONT OF THE APPROACHING FALL
SEASON...WITH TEMPERATURES FALLING 10-15 DEGREES FROM SATURDAYS
HIGHS. PORTIONS OF THE WASATCH FRONT MAY STRUGGLE TO EVEN REACH 70F
SUNDAY AFTERNOON.

&&

.FIRE WEATHER...A FAIRLY STRONG TROUGH WILL SLOWLY CROSS THE
NORTHWESTERN PORTION OF THE COUNTRY OVER THE NEXT SEVERAL DAYS.
AHEAD OF THIS SYSTEM...EXPECT GUSTY SOUTHERLY WINDS ACROSS MUCH OF
THE DISTRICT THROUGH AT LEAST SATURDAY. THE BEST CHANCE FOR
HUMIDITIES TO FALL BELOW CRITICAL LEVELS WILL BE ACROSS THE WEST
DESERTS THROUGH THIS PERIOD. LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE THROUGH SATURDAY IN LOCATIONS WITH
CRITICAL FUELS...ESPECIALLY ACROSS THE WESTERN DESERTS. AT THIS
TIME...THESE LOCATIONS DO NOT HAVE CRITICAL FUELS...SO HELD OFF ON
ANY FIRE WEATHER WATCHES OR RED FLAG WARNINGS.

A COLD FRONT WILL CROSS THE DISTRICT SUNDAY...BRINGING MUCH COOLER
TEMPERATURES AND A REDUCTION IN WINDS THROUGH AT LEAST EARLY NEXT
WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS WILL CONTINUE AT THE SLC TERMINAL
THROUGH THE DAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 021044
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
444 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. COOL FALL LIKE
TEMPERATURES ARE EXPECTED OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SUNDAY)...THE UPPER LOW CURRENTLY ALONG THE
BRITCOL COAST WILL CONTINUE ON A SLOW SOUTHWARD DRIFT INTO THE
PACIFIC NORTHWEST LATE IN THE WEEK. THE RESULTANT UNSEASONABLY
DEEP TROUGH ACROSS THE WEST COAST STATES WILL LEAVE THE GREAT
BASIN UNDER AN INCREASINGLY STRONG SOUTHWEST FLOW THROUGH THE
FIRST HALF OF THE UPCOMING WEEKEND.

THE INCREASING SOUTHWEST FLOW ALOFT COMBINED WITH THE SURFACE
TROUGH ALONG THE UTAH/NEVADA BORDER WILL RESULT IN STRONG
SOUTHERLY WINDS ACROSS THE WESTERN AND NORTHERN VALLEYS INTO THE
FIRST HALF OF THE WEEKEND. NOT ANTICIPATING ANY WIND HIGHLIGHTS
TODAY...BUT COULD SEE SOME ISSUES DEVELOP BY LATE THURSDAY AS THE
ADVANCING UPPER TROUGH NUDGES A FAIRLY STRONG COLD FRONT CLOSER TO
THE STATE. FRIDAY AND SATURDAY WILL SEE THE STRONGEST WINDS AS THE
COLD FRONT POSITIONS NEAR THE UTAH/NEVADA BORDER. AN HIGH WIND
EVENT COULD FORM IN THIS PATTERN AS NEAR 700 MB WINDS REACH 40
PLUS KNOTS AND THE THERMAL GRADIENT TIGHTENS IN ASSOCIATION WITH
THE SURFACE FRONT.

GOES IMAGERY STILL SHOWS HIGHER PWAT VALUES ACROSS ARIZONA AND
EXTREME SOUTHERN AND EASTERN UTAH. LOOKING AT A FEW THUNDERSTORMS
FORMING ALONG THE BOUNDARY BETWEEN THE MOISTURE PLUME AND THE
DRIER AIR TO THE WEST ACROSS SOUTH-CENTRAL THROUGH NORTHEAST UTAH
THIS AFTERNOON/EVENING. OVER NORTHERN UTAH AND AREA OF .60-.70
INCH PWAT VALUES MAY HELP FUEL CONVECTION LATER THIS AFTERNOON.
THE PAST COUPLE OF MODEL RUNS OF THE NAM/GFS HAVE INDICATED A BAND
OF PRECIP STRETCHED SOUTHWEST TO NORTHEAST ACROSS NORTHWEST UTAH
LATE THIS AFTERNOON AND EVENING. THIS BAND OF PRECIP APPEARS TO BE
CONCENTRATED NEAR THE SURFACE TROUGH AND UNDERNEATH AN AREA OF
UPPER DIVERGENCE ASSOCIATED WITH THE ENTRANCE REGION OF A MODEST
UPPER JET. SUSPECT THE QPF FIELDS ARE A BIT OVERDONE IN THE TWO
MODELS...BUT DO SEE THE POTENTIAL FOR AT LEAST ISOLATED CONVECTION
FORMING ACROSS THE NORTHWEST PER THE MODEL SOLUTION.

QUESTION FOR UPCOMING WEEKEND WILL BE HOW MUCH COOLING TO EXPECT
AND WHETHER ANY SIGNIFICANT PRECIP DEVELOPS WITH THE UPPER TROUGH
AND ASSOCIATED SURFACE FRONT. AT THIS POINT IT APPEARS THAT COOLER
FALL-LIKE TEMPS ARE A GIVEN BEHIND THE COLD FRONT ACROSS WEST-
CENTRAL THROUGH NORTHERN UTAH THIS WEEKEND. AS FAR AS PRECIP WOULD
EXPECTED CONVECTION TO FORM ALONG THE FRONTAL BOUNDARY AND THEN
EXTEND BACK INTO THE COLDER AIR TO THE NORTHWEST. CONVERGENCE INTO
THE SURFACE BOUNDARY SUPPORTED BY DYNAMIC LIFT FROM SHORTWAVES
EJECTING OUT AHEAD OF THE MAIN TROUGH WILL SUPPLY THE LIFT
NECESSARY FOR CONVECTIVE PRECIP ACROSS NORTHWEST UTAH. MOISTURE
WILL BE SOMEWHAT LIMITED...SO NOT ANTICIPATING ANY HEAVY PRECIP OR
STRONG THUNDERSTORMS AT THIS TIME THROUGH SATURDAY EVENING.

.LONG TERM (AFTER 06Z SUNDAY)...GLOBAL MODELS HAVE STARTED TO COME
INTO BETTER AGREEMENT WITH A FAIRLY STRONG...COLD PACIFIC TROUGH
EXPECTED TO CROSS THE NORTHERN INTERMOUNTAIN REGION/NORTHERN ROCKIES
SUNDAY. IN A FLIP FROM EARLIER RUNS...THE 00Z EC IS ACTUALLY A BIT
QUICKER WITH THIS SYSTEM. THE 00Z CANADIAN CONTINUED TO BE THE
SLOWEST MODEL...WITH THE SYSTEM CROSSING THE AREA LATER SUNDAY. THIS
SYSTEM IS ALSO QUITE A BIT DEEPER AS REPRESENTED IN THE CANADIAN.

IN GENERAL...A FAIRLY POTENT PACIFIC TROUGH IS EXPECTED TO CROSS THE
NORTHERN INTERMOUNTAIN/NORTHERN GREAT BASIN AREA DURING THE DAY
SUNDAY. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS
NORTHERN UTAH EARLY SUNDAY...REACHING AT LEAST CENTRAL UTAH BY
SUNDAY AFTERNOON BEFORE WEAKENING AS THE TROUGH ACCELERATES AWAY
FROM THE REGION. UNLIKE THE GFS RUNS OF THE PAST SEVERAL DAYS...THE
00Z RUN NOW DEPICTS 700MB TEMPERATURES FALLING TO NEAR -1C ALONG THE
UTAH/IDAHO BORDER BY 12Z SUNDAY. THIS MATCHES FAIRLY WELL WITH THE
00Z EC.

THE GLOBAL MODELS DIVERGE QUITE A BIT AFTER SUNDAY. THE GFS TAKES
THE SHORTWAVE DROPPING DOWN THE PACIFIC COAST IN THE WAKE OF THE
PREVIOUS SYSTEM AND DEVELOPS SOMEWHAT OF A CUT-OFF LOW OFF THE
CALIFORNIA COAST MONDAY. WITH THE LOW IN THIS POSITION...MOISTURE
SURGES INTO PORTIONS OF UTAH. MUCH OF THE REMAINDER OF THE GLOBAL
MODEL GUIDANCE VARIES SIGNIFICANTLY FROM THIS SOLUTION. FORECAST
PACKAGE ALREADY INCLUDED LOW END POPS ACROSS THE SOUTHERN MOUNTAINS.
LEFT THESE IN THE CURRENT PACKAGE GIVEN THE SIGNIFICANT VARIATION
BETWEEN THE GLOBAL MODELS. EVEN THESE LOW END POPS ARE TOO HIGH FOR
MOST OF THE GLOBAL GUIDANCE.

THE BIGGEST MESSAGE FOR THE LONG TERM PORTION OF THE FORECAST IS A
FAIRLY SIGNIFICANT COOL DOWN CAN BE EXPECTED SUNDAY ACROSS MUCH OF
THE STATE BEHIND THE FIRST REAL COLD FRONT OF THE APPROACHING FALL
SEASON...WITH TEMPERATURES FALLING 10-15 DEGREES FROM SATURDAYS
HIGHS. PORTIONS OF THE WASATCH FRONT MAY STRUGGLE TO EVEN REACH 70F
SUNDAY AFTERNOON.

&&

.FIRE WEATHER...A FAIRLY STRONG TROUGH WILL SLOWLY CROSS THE
NORTHWESTERN PORTION OF THE COUNTRY OVER THE NEXT SEVERAL DAYS.
AHEAD OF THIS SYSTEM...EXPECT GUSTY SOUTHERLY WINDS ACROSS MUCH OF
THE DISTRICT THROUGH AT LEAST SATURDAY. THE BEST CHANCE FOR
HUMIDITIES TO FALL BELOW CRITICAL LEVELS WILL BE ACROSS THE WEST
DESERTS THROUGH THIS PERIOD. LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE THROUGH SATURDAY IN LOCATIONS WITH
CRITICAL FUELS...ESPECIALLY ACROSS THE WESTERN DESERTS. AT THIS
TIME...THESE LOCATIONS DO NOT HAVE CRITICAL FUELS...SO HELD OFF ON
ANY FIRE WEATHER WATCHES OR RED FLAG WARNINGS.

A COLD FRONT WILL CROSS THE DISTRICT SUNDAY...BRINGING MUCH COOLER
TEMPERATURES AND A REDUCTION IN WINDS THROUGH AT LEAST EARLY NEXT
WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS WILL CONTINUE AT THE SLC TERMINAL
THROUGH THE DAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 021044
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
444 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. COOL FALL LIKE
TEMPERATURES ARE EXPECTED OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SUNDAY)...THE UPPER LOW CURRENTLY ALONG THE
BRITCOL COAST WILL CONTINUE ON A SLOW SOUTHWARD DRIFT INTO THE
PACIFIC NORTHWEST LATE IN THE WEEK. THE RESULTANT UNSEASONABLY
DEEP TROUGH ACROSS THE WEST COAST STATES WILL LEAVE THE GREAT
BASIN UNDER AN INCREASINGLY STRONG SOUTHWEST FLOW THROUGH THE
FIRST HALF OF THE UPCOMING WEEKEND.

THE INCREASING SOUTHWEST FLOW ALOFT COMBINED WITH THE SURFACE
TROUGH ALONG THE UTAH/NEVADA BORDER WILL RESULT IN STRONG
SOUTHERLY WINDS ACROSS THE WESTERN AND NORTHERN VALLEYS INTO THE
FIRST HALF OF THE WEEKEND. NOT ANTICIPATING ANY WIND HIGHLIGHTS
TODAY...BUT COULD SEE SOME ISSUES DEVELOP BY LATE THURSDAY AS THE
ADVANCING UPPER TROUGH NUDGES A FAIRLY STRONG COLD FRONT CLOSER TO
THE STATE. FRIDAY AND SATURDAY WILL SEE THE STRONGEST WINDS AS THE
COLD FRONT POSITIONS NEAR THE UTAH/NEVADA BORDER. AN HIGH WIND
EVENT COULD FORM IN THIS PATTERN AS NEAR 700 MB WINDS REACH 40
PLUS KNOTS AND THE THERMAL GRADIENT TIGHTENS IN ASSOCIATION WITH
THE SURFACE FRONT.

GOES IMAGERY STILL SHOWS HIGHER PWAT VALUES ACROSS ARIZONA AND
EXTREME SOUTHERN AND EASTERN UTAH. LOOKING AT A FEW THUNDERSTORMS
FORMING ALONG THE BOUNDARY BETWEEN THE MOISTURE PLUME AND THE
DRIER AIR TO THE WEST ACROSS SOUTH-CENTRAL THROUGH NORTHEAST UTAH
THIS AFTERNOON/EVENING. OVER NORTHERN UTAH AND AREA OF .60-.70
INCH PWAT VALUES MAY HELP FUEL CONVECTION LATER THIS AFTERNOON.
THE PAST COUPLE OF MODEL RUNS OF THE NAM/GFS HAVE INDICATED A BAND
OF PRECIP STRETCHED SOUTHWEST TO NORTHEAST ACROSS NORTHWEST UTAH
LATE THIS AFTERNOON AND EVENING. THIS BAND OF PRECIP APPEARS TO BE
CONCENTRATED NEAR THE SURFACE TROUGH AND UNDERNEATH AN AREA OF
UPPER DIVERGENCE ASSOCIATED WITH THE ENTRANCE REGION OF A MODEST
UPPER JET. SUSPECT THE QPF FIELDS ARE A BIT OVERDONE IN THE TWO
MODELS...BUT DO SEE THE POTENTIAL FOR AT LEAST ISOLATED CONVECTION
FORMING ACROSS THE NORTHWEST PER THE MODEL SOLUTION.

QUESTION FOR UPCOMING WEEKEND WILL BE HOW MUCH COOLING TO EXPECT
AND WHETHER ANY SIGNIFICANT PRECIP DEVELOPS WITH THE UPPER TROUGH
AND ASSOCIATED SURFACE FRONT. AT THIS POINT IT APPEARS THAT COOLER
FALL-LIKE TEMPS ARE A GIVEN BEHIND THE COLD FRONT ACROSS WEST-
CENTRAL THROUGH NORTHERN UTAH THIS WEEKEND. AS FAR AS PRECIP WOULD
EXPECTED CONVECTION TO FORM ALONG THE FRONTAL BOUNDARY AND THEN
EXTEND BACK INTO THE COLDER AIR TO THE NORTHWEST. CONVERGENCE INTO
THE SURFACE BOUNDARY SUPPORTED BY DYNAMIC LIFT FROM SHORTWAVES
EJECTING OUT AHEAD OF THE MAIN TROUGH WILL SUPPLY THE LIFT
NECESSARY FOR CONVECTIVE PRECIP ACROSS NORTHWEST UTAH. MOISTURE
WILL BE SOMEWHAT LIMITED...SO NOT ANTICIPATING ANY HEAVY PRECIP OR
STRONG THUNDERSTORMS AT THIS TIME THROUGH SATURDAY EVENING.

.LONG TERM (AFTER 06Z SUNDAY)...GLOBAL MODELS HAVE STARTED TO COME
INTO BETTER AGREEMENT WITH A FAIRLY STRONG...COLD PACIFIC TROUGH
EXPECTED TO CROSS THE NORTHERN INTERMOUNTAIN REGION/NORTHERN ROCKIES
SUNDAY. IN A FLIP FROM EARLIER RUNS...THE 00Z EC IS ACTUALLY A BIT
QUICKER WITH THIS SYSTEM. THE 00Z CANADIAN CONTINUED TO BE THE
SLOWEST MODEL...WITH THE SYSTEM CROSSING THE AREA LATER SUNDAY. THIS
SYSTEM IS ALSO QUITE A BIT DEEPER AS REPRESENTED IN THE CANADIAN.

IN GENERAL...A FAIRLY POTENT PACIFIC TROUGH IS EXPECTED TO CROSS THE
NORTHERN INTERMOUNTAIN/NORTHERN GREAT BASIN AREA DURING THE DAY
SUNDAY. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS
NORTHERN UTAH EARLY SUNDAY...REACHING AT LEAST CENTRAL UTAH BY
SUNDAY AFTERNOON BEFORE WEAKENING AS THE TROUGH ACCELERATES AWAY
FROM THE REGION. UNLIKE THE GFS RUNS OF THE PAST SEVERAL DAYS...THE
00Z RUN NOW DEPICTS 700MB TEMPERATURES FALLING TO NEAR -1C ALONG THE
UTAH/IDAHO BORDER BY 12Z SUNDAY. THIS MATCHES FAIRLY WELL WITH THE
00Z EC.

THE GLOBAL MODELS DIVERGE QUITE A BIT AFTER SUNDAY. THE GFS TAKES
THE SHORTWAVE DROPPING DOWN THE PACIFIC COAST IN THE WAKE OF THE
PREVIOUS SYSTEM AND DEVELOPS SOMEWHAT OF A CUT-OFF LOW OFF THE
CALIFORNIA COAST MONDAY. WITH THE LOW IN THIS POSITION...MOISTURE
SURGES INTO PORTIONS OF UTAH. MUCH OF THE REMAINDER OF THE GLOBAL
MODEL GUIDANCE VARIES SIGNIFICANTLY FROM THIS SOLUTION. FORECAST
PACKAGE ALREADY INCLUDED LOW END POPS ACROSS THE SOUTHERN MOUNTAINS.
LEFT THESE IN THE CURRENT PACKAGE GIVEN THE SIGNIFICANT VARIATION
BETWEEN THE GLOBAL MODELS. EVEN THESE LOW END POPS ARE TOO HIGH FOR
MOST OF THE GLOBAL GUIDANCE.

THE BIGGEST MESSAGE FOR THE LONG TERM PORTION OF THE FORECAST IS A
FAIRLY SIGNIFICANT COOL DOWN CAN BE EXPECTED SUNDAY ACROSS MUCH OF
THE STATE BEHIND THE FIRST REAL COLD FRONT OF THE APPROACHING FALL
SEASON...WITH TEMPERATURES FALLING 10-15 DEGREES FROM SATURDAYS
HIGHS. PORTIONS OF THE WASATCH FRONT MAY STRUGGLE TO EVEN REACH 70F
SUNDAY AFTERNOON.

&&

.FIRE WEATHER...A FAIRLY STRONG TROUGH WILL SLOWLY CROSS THE
NORTHWESTERN PORTION OF THE COUNTRY OVER THE NEXT SEVERAL DAYS.
AHEAD OF THIS SYSTEM...EXPECT GUSTY SOUTHERLY WINDS ACROSS MUCH OF
THE DISTRICT THROUGH AT LEAST SATURDAY. THE BEST CHANCE FOR
HUMIDITIES TO FALL BELOW CRITICAL LEVELS WILL BE ACROSS THE WEST
DESERTS THROUGH THIS PERIOD. LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE THROUGH SATURDAY IN LOCATIONS WITH
CRITICAL FUELS...ESPECIALLY ACROSS THE WESTERN DESERTS. AT THIS
TIME...THESE LOCATIONS DO NOT HAVE CRITICAL FUELS...SO HELD OFF ON
ANY FIRE WEATHER WATCHES OR RED FLAG WARNINGS.

A COLD FRONT WILL CROSS THE DISTRICT SUNDAY...BRINGING MUCH COOLER
TEMPERATURES AND A REDUCTION IN WINDS THROUGH AT LEAST EARLY NEXT
WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS WILL CONTINUE AT THE SLC TERMINAL
THROUGH THE DAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 021044
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
444 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. COOL FALL LIKE
TEMPERATURES ARE EXPECTED OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SUNDAY)...THE UPPER LOW CURRENTLY ALONG THE
BRITCOL COAST WILL CONTINUE ON A SLOW SOUTHWARD DRIFT INTO THE
PACIFIC NORTHWEST LATE IN THE WEEK. THE RESULTANT UNSEASONABLY
DEEP TROUGH ACROSS THE WEST COAST STATES WILL LEAVE THE GREAT
BASIN UNDER AN INCREASINGLY STRONG SOUTHWEST FLOW THROUGH THE
FIRST HALF OF THE UPCOMING WEEKEND.

THE INCREASING SOUTHWEST FLOW ALOFT COMBINED WITH THE SURFACE
TROUGH ALONG THE UTAH/NEVADA BORDER WILL RESULT IN STRONG
SOUTHERLY WINDS ACROSS THE WESTERN AND NORTHERN VALLEYS INTO THE
FIRST HALF OF THE WEEKEND. NOT ANTICIPATING ANY WIND HIGHLIGHTS
TODAY...BUT COULD SEE SOME ISSUES DEVELOP BY LATE THURSDAY AS THE
ADVANCING UPPER TROUGH NUDGES A FAIRLY STRONG COLD FRONT CLOSER TO
THE STATE. FRIDAY AND SATURDAY WILL SEE THE STRONGEST WINDS AS THE
COLD FRONT POSITIONS NEAR THE UTAH/NEVADA BORDER. AN HIGH WIND
EVENT COULD FORM IN THIS PATTERN AS NEAR 700 MB WINDS REACH 40
PLUS KNOTS AND THE THERMAL GRADIENT TIGHTENS IN ASSOCIATION WITH
THE SURFACE FRONT.

GOES IMAGERY STILL SHOWS HIGHER PWAT VALUES ACROSS ARIZONA AND
EXTREME SOUTHERN AND EASTERN UTAH. LOOKING AT A FEW THUNDERSTORMS
FORMING ALONG THE BOUNDARY BETWEEN THE MOISTURE PLUME AND THE
DRIER AIR TO THE WEST ACROSS SOUTH-CENTRAL THROUGH NORTHEAST UTAH
THIS AFTERNOON/EVENING. OVER NORTHERN UTAH AND AREA OF .60-.70
INCH PWAT VALUES MAY HELP FUEL CONVECTION LATER THIS AFTERNOON.
THE PAST COUPLE OF MODEL RUNS OF THE NAM/GFS HAVE INDICATED A BAND
OF PRECIP STRETCHED SOUTHWEST TO NORTHEAST ACROSS NORTHWEST UTAH
LATE THIS AFTERNOON AND EVENING. THIS BAND OF PRECIP APPEARS TO BE
CONCENTRATED NEAR THE SURFACE TROUGH AND UNDERNEATH AN AREA OF
UPPER DIVERGENCE ASSOCIATED WITH THE ENTRANCE REGION OF A MODEST
UPPER JET. SUSPECT THE QPF FIELDS ARE A BIT OVERDONE IN THE TWO
MODELS...BUT DO SEE THE POTENTIAL FOR AT LEAST ISOLATED CONVECTION
FORMING ACROSS THE NORTHWEST PER THE MODEL SOLUTION.

QUESTION FOR UPCOMING WEEKEND WILL BE HOW MUCH COOLING TO EXPECT
AND WHETHER ANY SIGNIFICANT PRECIP DEVELOPS WITH THE UPPER TROUGH
AND ASSOCIATED SURFACE FRONT. AT THIS POINT IT APPEARS THAT COOLER
FALL-LIKE TEMPS ARE A GIVEN BEHIND THE COLD FRONT ACROSS WEST-
CENTRAL THROUGH NORTHERN UTAH THIS WEEKEND. AS FAR AS PRECIP WOULD
EXPECTED CONVECTION TO FORM ALONG THE FRONTAL BOUNDARY AND THEN
EXTEND BACK INTO THE COLDER AIR TO THE NORTHWEST. CONVERGENCE INTO
THE SURFACE BOUNDARY SUPPORTED BY DYNAMIC LIFT FROM SHORTWAVES
EJECTING OUT AHEAD OF THE MAIN TROUGH WILL SUPPLY THE LIFT
NECESSARY FOR CONVECTIVE PRECIP ACROSS NORTHWEST UTAH. MOISTURE
WILL BE SOMEWHAT LIMITED...SO NOT ANTICIPATING ANY HEAVY PRECIP OR
STRONG THUNDERSTORMS AT THIS TIME THROUGH SATURDAY EVENING.

.LONG TERM (AFTER 06Z SUNDAY)...GLOBAL MODELS HAVE STARTED TO COME
INTO BETTER AGREEMENT WITH A FAIRLY STRONG...COLD PACIFIC TROUGH
EXPECTED TO CROSS THE NORTHERN INTERMOUNTAIN REGION/NORTHERN ROCKIES
SUNDAY. IN A FLIP FROM EARLIER RUNS...THE 00Z EC IS ACTUALLY A BIT
QUICKER WITH THIS SYSTEM. THE 00Z CANADIAN CONTINUED TO BE THE
SLOWEST MODEL...WITH THE SYSTEM CROSSING THE AREA LATER SUNDAY. THIS
SYSTEM IS ALSO QUITE A BIT DEEPER AS REPRESENTED IN THE CANADIAN.

IN GENERAL...A FAIRLY POTENT PACIFIC TROUGH IS EXPECTED TO CROSS THE
NORTHERN INTERMOUNTAIN/NORTHERN GREAT BASIN AREA DURING THE DAY
SUNDAY. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS
NORTHERN UTAH EARLY SUNDAY...REACHING AT LEAST CENTRAL UTAH BY
SUNDAY AFTERNOON BEFORE WEAKENING AS THE TROUGH ACCELERATES AWAY
FROM THE REGION. UNLIKE THE GFS RUNS OF THE PAST SEVERAL DAYS...THE
00Z RUN NOW DEPICTS 700MB TEMPERATURES FALLING TO NEAR -1C ALONG THE
UTAH/IDAHO BORDER BY 12Z SUNDAY. THIS MATCHES FAIRLY WELL WITH THE
00Z EC.

THE GLOBAL MODELS DIVERGE QUITE A BIT AFTER SUNDAY. THE GFS TAKES
THE SHORTWAVE DROPPING DOWN THE PACIFIC COAST IN THE WAKE OF THE
PREVIOUS SYSTEM AND DEVELOPS SOMEWHAT OF A CUT-OFF LOW OFF THE
CALIFORNIA COAST MONDAY. WITH THE LOW IN THIS POSITION...MOISTURE
SURGES INTO PORTIONS OF UTAH. MUCH OF THE REMAINDER OF THE GLOBAL
MODEL GUIDANCE VARIES SIGNIFICANTLY FROM THIS SOLUTION. FORECAST
PACKAGE ALREADY INCLUDED LOW END POPS ACROSS THE SOUTHERN MOUNTAINS.
LEFT THESE IN THE CURRENT PACKAGE GIVEN THE SIGNIFICANT VARIATION
BETWEEN THE GLOBAL MODELS. EVEN THESE LOW END POPS ARE TOO HIGH FOR
MOST OF THE GLOBAL GUIDANCE.

THE BIGGEST MESSAGE FOR THE LONG TERM PORTION OF THE FORECAST IS A
FAIRLY SIGNIFICANT COOL DOWN CAN BE EXPECTED SUNDAY ACROSS MUCH OF
THE STATE BEHIND THE FIRST REAL COLD FRONT OF THE APPROACHING FALL
SEASON...WITH TEMPERATURES FALLING 10-15 DEGREES FROM SATURDAYS
HIGHS. PORTIONS OF THE WASATCH FRONT MAY STRUGGLE TO EVEN REACH 70F
SUNDAY AFTERNOON.

&&

.FIRE WEATHER...A FAIRLY STRONG TROUGH WILL SLOWLY CROSS THE
NORTHWESTERN PORTION OF THE COUNTRY OVER THE NEXT SEVERAL DAYS.
AHEAD OF THIS SYSTEM...EXPECT GUSTY SOUTHERLY WINDS ACROSS MUCH OF
THE DISTRICT THROUGH AT LEAST SATURDAY. THE BEST CHANCE FOR
HUMIDITIES TO FALL BELOW CRITICAL LEVELS WILL BE ACROSS THE WEST
DESERTS THROUGH THIS PERIOD. LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE THROUGH SATURDAY IN LOCATIONS WITH
CRITICAL FUELS...ESPECIALLY ACROSS THE WESTERN DESERTS. AT THIS
TIME...THESE LOCATIONS DO NOT HAVE CRITICAL FUELS...SO HELD OFF ON
ANY FIRE WEATHER WATCHES OR RED FLAG WARNINGS.

A COLD FRONT WILL CROSS THE DISTRICT SUNDAY...BRINGING MUCH COOLER
TEMPERATURES AND A REDUCTION IN WINDS THROUGH AT LEAST EARLY NEXT
WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS WILL CONTINUE AT THE SLC TERMINAL
THROUGH THE DAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 021044
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
444 AM MDT WED SEP 2 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH OVER WESTERN CANADA WILL SETTLE
INTO THE PACIFIC NORTHWEST LATE THIS WEEK...THEN SWING EAST ACROSS
THE GREAT BASIN AND NORTHERN ROCKIES THIS WEEKEND. COOL FALL LIKE
TEMPERATURES ARE EXPECTED OVER THE LABOR DAY WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SUNDAY)...THE UPPER LOW CURRENTLY ALONG THE
BRITCOL COAST WILL CONTINUE ON A SLOW SOUTHWARD DRIFT INTO THE
PACIFIC NORTHWEST LATE IN THE WEEK. THE RESULTANT UNSEASONABLY
DEEP TROUGH ACROSS THE WEST COAST STATES WILL LEAVE THE GREAT
BASIN UNDER AN INCREASINGLY STRONG SOUTHWEST FLOW THROUGH THE
FIRST HALF OF THE UPCOMING WEEKEND.

THE INCREASING SOUTHWEST FLOW ALOFT COMBINED WITH THE SURFACE
TROUGH ALONG THE UTAH/NEVADA BORDER WILL RESULT IN STRONG
SOUTHERLY WINDS ACROSS THE WESTERN AND NORTHERN VALLEYS INTO THE
FIRST HALF OF THE WEEKEND. NOT ANTICIPATING ANY WIND HIGHLIGHTS
TODAY...BUT COULD SEE SOME ISSUES DEVELOP BY LATE THURSDAY AS THE
ADVANCING UPPER TROUGH NUDGES A FAIRLY STRONG COLD FRONT CLOSER TO
THE STATE. FRIDAY AND SATURDAY WILL SEE THE STRONGEST WINDS AS THE
COLD FRONT POSITIONS NEAR THE UTAH/NEVADA BORDER. AN HIGH WIND
EVENT COULD FORM IN THIS PATTERN AS NEAR 700 MB WINDS REACH 40
PLUS KNOTS AND THE THERMAL GRADIENT TIGHTENS IN ASSOCIATION WITH
THE SURFACE FRONT.

GOES IMAGERY STILL SHOWS HIGHER PWAT VALUES ACROSS ARIZONA AND
EXTREME SOUTHERN AND EASTERN UTAH. LOOKING AT A FEW THUNDERSTORMS
FORMING ALONG THE BOUNDARY BETWEEN THE MOISTURE PLUME AND THE
DRIER AIR TO THE WEST ACROSS SOUTH-CENTRAL THROUGH NORTHEAST UTAH
THIS AFTERNOON/EVENING. OVER NORTHERN UTAH AND AREA OF .60-.70
INCH PWAT VALUES MAY HELP FUEL CONVECTION LATER THIS AFTERNOON.
THE PAST COUPLE OF MODEL RUNS OF THE NAM/GFS HAVE INDICATED A BAND
OF PRECIP STRETCHED SOUTHWEST TO NORTHEAST ACROSS NORTHWEST UTAH
LATE THIS AFTERNOON AND EVENING. THIS BAND OF PRECIP APPEARS TO BE
CONCENTRATED NEAR THE SURFACE TROUGH AND UNDERNEATH AN AREA OF
UPPER DIVERGENCE ASSOCIATED WITH THE ENTRANCE REGION OF A MODEST
UPPER JET. SUSPECT THE QPF FIELDS ARE A BIT OVERDONE IN THE TWO
MODELS...BUT DO SEE THE POTENTIAL FOR AT LEAST ISOLATED CONVECTION
FORMING ACROSS THE NORTHWEST PER THE MODEL SOLUTION.

QUESTION FOR UPCOMING WEEKEND WILL BE HOW MUCH COOLING TO EXPECT
AND WHETHER ANY SIGNIFICANT PRECIP DEVELOPS WITH THE UPPER TROUGH
AND ASSOCIATED SURFACE FRONT. AT THIS POINT IT APPEARS THAT COOLER
FALL-LIKE TEMPS ARE A GIVEN BEHIND THE COLD FRONT ACROSS WEST-
CENTRAL THROUGH NORTHERN UTAH THIS WEEKEND. AS FAR AS PRECIP WOULD
EXPECTED CONVECTION TO FORM ALONG THE FRONTAL BOUNDARY AND THEN
EXTEND BACK INTO THE COLDER AIR TO THE NORTHWEST. CONVERGENCE INTO
THE SURFACE BOUNDARY SUPPORTED BY DYNAMIC LIFT FROM SHORTWAVES
EJECTING OUT AHEAD OF THE MAIN TROUGH WILL SUPPLY THE LIFT
NECESSARY FOR CONVECTIVE PRECIP ACROSS NORTHWEST UTAH. MOISTURE
WILL BE SOMEWHAT LIMITED...SO NOT ANTICIPATING ANY HEAVY PRECIP OR
STRONG THUNDERSTORMS AT THIS TIME THROUGH SATURDAY EVENING.

.LONG TERM (AFTER 06Z SUNDAY)...GLOBAL MODELS HAVE STARTED TO COME
INTO BETTER AGREEMENT WITH A FAIRLY STRONG...COLD PACIFIC TROUGH
EXPECTED TO CROSS THE NORTHERN INTERMOUNTAIN REGION/NORTHERN ROCKIES
SUNDAY. IN A FLIP FROM EARLIER RUNS...THE 00Z EC IS ACTUALLY A BIT
QUICKER WITH THIS SYSTEM. THE 00Z CANADIAN CONTINUED TO BE THE
SLOWEST MODEL...WITH THE SYSTEM CROSSING THE AREA LATER SUNDAY. THIS
SYSTEM IS ALSO QUITE A BIT DEEPER AS REPRESENTED IN THE CANADIAN.

IN GENERAL...A FAIRLY POTENT PACIFIC TROUGH IS EXPECTED TO CROSS THE
NORTHERN INTERMOUNTAIN/NORTHERN GREAT BASIN AREA DURING THE DAY
SUNDAY. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE ACROSS
NORTHERN UTAH EARLY SUNDAY...REACHING AT LEAST CENTRAL UTAH BY
SUNDAY AFTERNOON BEFORE WEAKENING AS THE TROUGH ACCELERATES AWAY
FROM THE REGION. UNLIKE THE GFS RUNS OF THE PAST SEVERAL DAYS...THE
00Z RUN NOW DEPICTS 700MB TEMPERATURES FALLING TO NEAR -1C ALONG THE
UTAH/IDAHO BORDER BY 12Z SUNDAY. THIS MATCHES FAIRLY WELL WITH THE
00Z EC.

THE GLOBAL MODELS DIVERGE QUITE A BIT AFTER SUNDAY. THE GFS TAKES
THE SHORTWAVE DROPPING DOWN THE PACIFIC COAST IN THE WAKE OF THE
PREVIOUS SYSTEM AND DEVELOPS SOMEWHAT OF A CUT-OFF LOW OFF THE
CALIFORNIA COAST MONDAY. WITH THE LOW IN THIS POSITION...MOISTURE
SURGES INTO PORTIONS OF UTAH. MUCH OF THE REMAINDER OF THE GLOBAL
MODEL GUIDANCE VARIES SIGNIFICANTLY FROM THIS SOLUTION. FORECAST
PACKAGE ALREADY INCLUDED LOW END POPS ACROSS THE SOUTHERN MOUNTAINS.
LEFT THESE IN THE CURRENT PACKAGE GIVEN THE SIGNIFICANT VARIATION
BETWEEN THE GLOBAL MODELS. EVEN THESE LOW END POPS ARE TOO HIGH FOR
MOST OF THE GLOBAL GUIDANCE.

THE BIGGEST MESSAGE FOR THE LONG TERM PORTION OF THE FORECAST IS A
FAIRLY SIGNIFICANT COOL DOWN CAN BE EXPECTED SUNDAY ACROSS MUCH OF
THE STATE BEHIND THE FIRST REAL COLD FRONT OF THE APPROACHING FALL
SEASON...WITH TEMPERATURES FALLING 10-15 DEGREES FROM SATURDAYS
HIGHS. PORTIONS OF THE WASATCH FRONT MAY STRUGGLE TO EVEN REACH 70F
SUNDAY AFTERNOON.

&&

.FIRE WEATHER...A FAIRLY STRONG TROUGH WILL SLOWLY CROSS THE
NORTHWESTERN PORTION OF THE COUNTRY OVER THE NEXT SEVERAL DAYS.
AHEAD OF THIS SYSTEM...EXPECT GUSTY SOUTHERLY WINDS ACROSS MUCH OF
THE DISTRICT THROUGH AT LEAST SATURDAY. THE BEST CHANCE FOR
HUMIDITIES TO FALL BELOW CRITICAL LEVELS WILL BE ACROSS THE WEST
DESERTS THROUGH THIS PERIOD. LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE THROUGH SATURDAY IN LOCATIONS WITH
CRITICAL FUELS...ESPECIALLY ACROSS THE WESTERN DESERTS. AT THIS
TIME...THESE LOCATIONS DO NOT HAVE CRITICAL FUELS...SO HELD OFF ON
ANY FIRE WEATHER WATCHES OR RED FLAG WARNINGS.

A COLD FRONT WILL CROSS THE DISTRICT SUNDAY...BRINGING MUCH COOLER
TEMPERATURES AND A REDUCTION IN WINDS THROUGH AT LEAST EARLY NEXT
WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS WILL CONTINUE AT THE SLC TERMINAL
THROUGH THE DAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

CONGER/KRUSE

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VISIT...
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000
FXUS65 KSLC 020343
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
943 PM MDT TUE SEP 1 2015

.SYNOPSIS...A MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
REGION THROUGH THE REMAINDER OF THE WEEK. A PACIFIC TROUGH WILL
MOVE INTO THE GREAT BASIN FOR THE WEEKEND...AND WILL BE
ACCOMPANIED BY A MUCH COOLER...FALL LIKE AIRMASS.


&&

.DISCUSSION...THE FORECAST AREA REMAINS UNDER SOUTHWEST FLOW THIS
EVENING BETWEEN THE RIDGE OVER THE CENTRAL UNITED STATES AND THE
TROUGH OFF THE PACIFIC NORTHWEST COAST. WESTERN UTAH HAS SEEN A
DRYING TREND WHILE MOISTURE LINGERS OVER EASTERN UTAH...WHERE
SHOWERS THAT DEVELOPED THIS AFTERNOON ARE CONTINUING INTO THE
EVENING HOURS. THESE STORMS WILL CONTINUE TO DISSIPATE...AND
COVERAGE TOMORROW AFTERNOON/EVENING WILL BE MORE ISOLATED IN
NATURE AS THE AIRMASS CONTINUES TO DRY. MAXES TODAY WERE VERY
CLOSE TO SEASONAL NORMALS OVER SOUTHERN UTAH AND JUST A FEW
DEGREES ABOVE OVER NORTHERN UTAH. SIMILAR TEMPERATURES ARE
EXPECTED TOMORROW.

SOUTHERLY WINDS WERE GUSTY AT TIMES TODAY AND THE FLOW ALOFT WILL
CONTINUE TO INCREASE TOMORROW AND THURSDAY AS THE PACIFIC
NORTHWEST TROUGH MOVES ONSHORE. BY THURSDAY...THE APPROACH OF THE
TROUGH WILL DRAW MOISTURE BACK INTO SOUTHERN AND EASTERN
UTAH...RESULTING IN INCREASING COVERAGE OF SHOWERS AND
THUNDERSTORMS. EC/GFS COMING INTO BETTER AGREEMENT WITH THE TRACK
OF THE TROUGH THURSDAY THROUGH THE WEEKEND...SLOWLY PIVOTING IT
ACROSS THE PACIFIC NORTHWEST FRIDAY BEFORE MOVING IT INTO NEVADA
ON SATURDAY AND ACROSS NORTHERN UTAH SATURDAY NIGHT/SUNDAY.
HOWEVER...SOME DIFFERENCES REMAIN IN THE SOLUTIONS. 18Z GFS NOW
KEEPS MOISTURE OVER EASTERN UTAH THROUGH THE WEEKEND WHILE THE 12Z EC
BRINGS A DRIER AIRMASS IN FRIDAY AND SATURDAY. OVERALL...POTENTIAL
FOR PRECIP IS NOT PARTICULARLY IMPRESSIVE...BUT THE SYSTEM WILL
BRING A SIGNIFICANT COLD FRONT ACROSS NORTHERN AND CENTRAL UTAH
SATURDAY NIGHT/SUNDAY...WITH 700 MB TEMPS PROGGED TO DROP FROM
+10C TO +12C TO AS LOW AS +3C BEHIND THE FRONT. MAXES COULD BE IN
EXCESS OF 15F BELOW SEASONAL NORMS BY SUNDAY...BRINGING THE FIRST
FALL-LIKE WEATHER OF THE SEASON.

NO UPDATES EXPECTED TO THE FORECAST THIS EVENING.

&&

.AVIATION...THE SLC TERMINAL WILL SEE VFR CONDITIONS THROUGH THE
NIGHT WITH SOME SCATTERED CLOUDS. SOUTHEAST WINDS ARE EXPECTED
THROUGH THE OVERNIGHT HOURS.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH
THURSDAY...RESULTING IN GUSTY SOUTHERLY WINDS DURING THE
AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH. THIS MAY RESULT IN
LOCAL CRITICAL FIRE WEATHER CONDITIONS IF FUELS BECOME
SUFFICIENTLY DRY. LINGERING MOISTURE MAY PRODUCE A FEW SHOWERS
OVER THE HIGHER TERRAIN TOMORROW AFTERNOON. INCREASING MOISTURE
OVER SOUTHEAST UTAH WILL RESULT IN AN INCREASE IN COVERAGE OF
CONVECTION ON THURSDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

TRAPHAGAN

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VISIT...
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000
FXUS65 KSLC 020343
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
943 PM MDT TUE SEP 1 2015

.SYNOPSIS...A MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
REGION THROUGH THE REMAINDER OF THE WEEK. A PACIFIC TROUGH WILL
MOVE INTO THE GREAT BASIN FOR THE WEEKEND...AND WILL BE
ACCOMPANIED BY A MUCH COOLER...FALL LIKE AIRMASS.


&&

.DISCUSSION...THE FORECAST AREA REMAINS UNDER SOUTHWEST FLOW THIS
EVENING BETWEEN THE RIDGE OVER THE CENTRAL UNITED STATES AND THE
TROUGH OFF THE PACIFIC NORTHWEST COAST. WESTERN UTAH HAS SEEN A
DRYING TREND WHILE MOISTURE LINGERS OVER EASTERN UTAH...WHERE
SHOWERS THAT DEVELOPED THIS AFTERNOON ARE CONTINUING INTO THE
EVENING HOURS. THESE STORMS WILL CONTINUE TO DISSIPATE...AND
COVERAGE TOMORROW AFTERNOON/EVENING WILL BE MORE ISOLATED IN
NATURE AS THE AIRMASS CONTINUES TO DRY. MAXES TODAY WERE VERY
CLOSE TO SEASONAL NORMALS OVER SOUTHERN UTAH AND JUST A FEW
DEGREES ABOVE OVER NORTHERN UTAH. SIMILAR TEMPERATURES ARE
EXPECTED TOMORROW.

SOUTHERLY WINDS WERE GUSTY AT TIMES TODAY AND THE FLOW ALOFT WILL
CONTINUE TO INCREASE TOMORROW AND THURSDAY AS THE PACIFIC
NORTHWEST TROUGH MOVES ONSHORE. BY THURSDAY...THE APPROACH OF THE
TROUGH WILL DRAW MOISTURE BACK INTO SOUTHERN AND EASTERN
UTAH...RESULTING IN INCREASING COVERAGE OF SHOWERS AND
THUNDERSTORMS. EC/GFS COMING INTO BETTER AGREEMENT WITH THE TRACK
OF THE TROUGH THURSDAY THROUGH THE WEEKEND...SLOWLY PIVOTING IT
ACROSS THE PACIFIC NORTHWEST FRIDAY BEFORE MOVING IT INTO NEVADA
ON SATURDAY AND ACROSS NORTHERN UTAH SATURDAY NIGHT/SUNDAY.
HOWEVER...SOME DIFFERENCES REMAIN IN THE SOLUTIONS. 18Z GFS NOW
KEEPS MOISTURE OVER EASTERN UTAH THROUGH THE WEEKEND WHILE THE 12Z EC
BRINGS A DRIER AIRMASS IN FRIDAY AND SATURDAY. OVERALL...POTENTIAL
FOR PRECIP IS NOT PARTICULARLY IMPRESSIVE...BUT THE SYSTEM WILL
BRING A SIGNIFICANT COLD FRONT ACROSS NORTHERN AND CENTRAL UTAH
SATURDAY NIGHT/SUNDAY...WITH 700 MB TEMPS PROGGED TO DROP FROM
+10C TO +12C TO AS LOW AS +3C BEHIND THE FRONT. MAXES COULD BE IN
EXCESS OF 15F BELOW SEASONAL NORMS BY SUNDAY...BRINGING THE FIRST
FALL-LIKE WEATHER OF THE SEASON.

NO UPDATES EXPECTED TO THE FORECAST THIS EVENING.

&&

.AVIATION...THE SLC TERMINAL WILL SEE VFR CONDITIONS THROUGH THE
NIGHT WITH SOME SCATTERED CLOUDS. SOUTHEAST WINDS ARE EXPECTED
THROUGH THE OVERNIGHT HOURS.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH
THURSDAY...RESULTING IN GUSTY SOUTHERLY WINDS DURING THE
AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH. THIS MAY RESULT IN
LOCAL CRITICAL FIRE WEATHER CONDITIONS IF FUELS BECOME
SUFFICIENTLY DRY. LINGERING MOISTURE MAY PRODUCE A FEW SHOWERS
OVER THE HIGHER TERRAIN TOMORROW AFTERNOON. INCREASING MOISTURE
OVER SOUTHEAST UTAH WILL RESULT IN AN INCREASE IN COVERAGE OF
CONVECTION ON THURSDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

TRAPHAGAN

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VISIT...
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000
FXUS65 KSLC 020343
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
943 PM MDT TUE SEP 1 2015

.SYNOPSIS...A MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
REGION THROUGH THE REMAINDER OF THE WEEK. A PACIFIC TROUGH WILL
MOVE INTO THE GREAT BASIN FOR THE WEEKEND...AND WILL BE
ACCOMPANIED BY A MUCH COOLER...FALL LIKE AIRMASS.


&&

.DISCUSSION...THE FORECAST AREA REMAINS UNDER SOUTHWEST FLOW THIS
EVENING BETWEEN THE RIDGE OVER THE CENTRAL UNITED STATES AND THE
TROUGH OFF THE PACIFIC NORTHWEST COAST. WESTERN UTAH HAS SEEN A
DRYING TREND WHILE MOISTURE LINGERS OVER EASTERN UTAH...WHERE
SHOWERS THAT DEVELOPED THIS AFTERNOON ARE CONTINUING INTO THE
EVENING HOURS. THESE STORMS WILL CONTINUE TO DISSIPATE...AND
COVERAGE TOMORROW AFTERNOON/EVENING WILL BE MORE ISOLATED IN
NATURE AS THE AIRMASS CONTINUES TO DRY. MAXES TODAY WERE VERY
CLOSE TO SEASONAL NORMALS OVER SOUTHERN UTAH AND JUST A FEW
DEGREES ABOVE OVER NORTHERN UTAH. SIMILAR TEMPERATURES ARE
EXPECTED TOMORROW.

SOUTHERLY WINDS WERE GUSTY AT TIMES TODAY AND THE FLOW ALOFT WILL
CONTINUE TO INCREASE TOMORROW AND THURSDAY AS THE PACIFIC
NORTHWEST TROUGH MOVES ONSHORE. BY THURSDAY...THE APPROACH OF THE
TROUGH WILL DRAW MOISTURE BACK INTO SOUTHERN AND EASTERN
UTAH...RESULTING IN INCREASING COVERAGE OF SHOWERS AND
THUNDERSTORMS. EC/GFS COMING INTO BETTER AGREEMENT WITH THE TRACK
OF THE TROUGH THURSDAY THROUGH THE WEEKEND...SLOWLY PIVOTING IT
ACROSS THE PACIFIC NORTHWEST FRIDAY BEFORE MOVING IT INTO NEVADA
ON SATURDAY AND ACROSS NORTHERN UTAH SATURDAY NIGHT/SUNDAY.
HOWEVER...SOME DIFFERENCES REMAIN IN THE SOLUTIONS. 18Z GFS NOW
KEEPS MOISTURE OVER EASTERN UTAH THROUGH THE WEEKEND WHILE THE 12Z EC
BRINGS A DRIER AIRMASS IN FRIDAY AND SATURDAY. OVERALL...POTENTIAL
FOR PRECIP IS NOT PARTICULARLY IMPRESSIVE...BUT THE SYSTEM WILL
BRING A SIGNIFICANT COLD FRONT ACROSS NORTHERN AND CENTRAL UTAH
SATURDAY NIGHT/SUNDAY...WITH 700 MB TEMPS PROGGED TO DROP FROM
+10C TO +12C TO AS LOW AS +3C BEHIND THE FRONT. MAXES COULD BE IN
EXCESS OF 15F BELOW SEASONAL NORMS BY SUNDAY...BRINGING THE FIRST
FALL-LIKE WEATHER OF THE SEASON.

NO UPDATES EXPECTED TO THE FORECAST THIS EVENING.

&&

.AVIATION...THE SLC TERMINAL WILL SEE VFR CONDITIONS THROUGH THE
NIGHT WITH SOME SCATTERED CLOUDS. SOUTHEAST WINDS ARE EXPECTED
THROUGH THE OVERNIGHT HOURS.

&&

.FIRE WEATHER...A DEVELOPING TROUGH ALONG THE WEST COAST WILL
RESULT IN AN INCREASE IN SOUTHWESTERLY FLOW THROUGH
THURSDAY...RESULTING IN GUSTY SOUTHERLY WINDS DURING THE
AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH. THIS MAY RESULT IN
LOCAL CRITICAL FIRE WEATHER CONDITIONS IF FUELS BECOME
SUFFICIENTLY DRY. LINGERING MOISTURE MAY PRODUCE A FEW SHOWERS
OVER THE HIGHER TERRAIN TOMORROW AFTERNOON. INCREASING MOISTURE
OVER SOUTHEAST UTAH WILL RESULT IN AN INCREASE IN COVERAGE OF
CONVECTION ON THURSDAY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277

&&

$$

TRAPHAGAN

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HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
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000
FXUS65 KSLC 012223
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
423 PM MDT TUE SEP 1 2015

.SYNOPSIS...A MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
REGION THROUGH THE REMAINDER OF THE WEEK. A PACIFIC TROUGH WILL
MOVE INTO THE GREAT BASIN FOR THE WEEKEND...AND WILL BE
ACCOMPANIED BY A MUCH COOLER...FALL LIKE AIRMASS.

&&

.SHORT TERM (THROUGH 06Z FRIDAY)...SOUTHWESTERLY FLOW ALOFT WILL
PREVAIL ACROSS THE INTERIOR WEST THROUGH THE SHORT TERM
PERIOD...DOWNSTREAM FROM AN UPPER TROUGH WHICH IS FORECAST TO
DEEPEN ALONG THE PACIFIC COAST. DESPITE GRADUAL DRYING OVER THE
PAST COUPLE OF DAYS LINGERING MOISTURE HAS PROVEN SUFFICIENT FOR
ISOLATED CONVECTION ACROSS THE EASTERN TWO THIRDS OF THE FORECAST
AREA THIS AFTERNOON. HAVE MAINTAINED ISOLATED CONVECTION INTO THE
EVENING HOURS ACROSS THE EASTERN HALF OF THE FORECAST AREA.

SOUTHWESTERLY FLOW IS FORECAST TO STRENGTHEN A BIT OVER THE NEXT
COUPLE DAYS RESULTING IN LOCALLY BREEZY CONDITIONS ACROSS WESTERN
UT WHILE MAINTAINING A MILD AIRMASS OVER THE FORECAST AREA. AS THE
AIRMASS CONTINUES TO DRY THE THREAT FOR CONVECTION WILL BE FURTHER
DIMINISHED...AND LIKELY CONFINED ONLY TO THE MOST FAVORABLE AREAS
SUCH AS BOULDER MOUNTAIN AND THE HIGH UINTAS.

WHILE THE OVERALL IDEA OF A STRENGTHENING SOUTHWESTERLY FLOW IS
AGREED UPON BETWEEN THE VARIOUS MODELS...THE DEGREE OF MOISTURE
THURSDAY INTO THURSDAY EVENING REMAINS THE SOURCE OF UNCERTAINTY
WITH THE FORECAST /DISCUSSED IN GREATER DETAIL IN THE LONG TERM
SECTION BELOW/. GIVEN THE AMPLITUDE OF THE UPSTREAM TROUGH SUSPECT
MOISTURE IN AT LEAST A LIMITED CAPACITY WILL MAKE IT INTO SOUTHERN
AND EASTERN PORTIONS OF THE CWA THURSDAY AFTERNOON...AND HAVE
BUMPED POPS 10 TO 20 PERCENT FOR THIS PERIOD.

.LONG TERM (AFTER 06Z FRIDAY)...MEDIUM RANGE MODELS IN GOOD
AGREEMENT WITH THE LARGE SCALE PATTERN INTO THE START OF THE
WEEKEND. AFTER THIS TIME THEY BEGIN TO DIVERGE AND CONFIDENCE IN
THE EVOLUTION OF THE PATTERN DECREASES. PERIOD BEGINS WITH A RIDGE
CENTERED OVER THE CENTRAL U.S. WITH A DEEP TROUGH ALONG THE WEST
COAST. THIS PLACES UTAH UNDER A PRETTY VIGOROUS SW FLOW ALOFT
THURSDAY NIGHT INTO SATURDAY. THE GFS SURGES HIGHER PW AIR INTO
EASTERN UT THU NGT AND DEVELOPS DECENT COVERAGE OF SHOWERS AND
THUNDERSTORMS...PARTICULARLY ACROSS THE ERN PORTION OF THE CWA.
THE CANADIAN AND ECMWF ARE RELUCTANT TO DEVELOP MUCH PRECIP AT
THIS TIME...BUT FEEL THAT THE POTENTIAL IS CERTAINLY THERE TO PULL
DEEPER MOISTURE N AHEAD OF THE APPROACHING FRONT. GIVEN THIS
POTENTIAL WILL INCREASE THE THREAT OF PRECIP JUST A BIT ON THU NGT
AND FRI ACROSS THE ERN HALF OF THE CWA.

EXPECT BREEZY TO WINDY SOUTH WINDS ACROSS MUCH OF THE STATE FRIDAY
AND SATURDAY AHEAD THE COLD FRONT ASSOCIATED WITH THE DEEP WESTERN
TROUGH. THE ECMWF...GFS AND CANADIAN MODELS ALL BRING A SIGNIFICANT
COLD FRONT THROUGH THE STATE SATURDAY NIGHT AND SUNDAY LEADING TO A
SIGNIFICANT COOL DOWN. TEMPERATURES ACROSS THE STATE WILL BE AROUND
15 DEGREES F BELOW NORMAL ON SUNDAY AND SOME AREAS ALONG THE WASATCH
FRONT MAY STRUGGLE TO REACH 70F. THE MEDIUM RANGE MODELS DON/T
DEVELOP MUCH PRECIP ALONG THE FRONT ALTHOUGH BELIEVE IT WILL BE
ACTIVE ACROSS NRN UT CLOSER TO THE LARGE SCALE DYNAMICS ASSOCIATED
WITH THE TROUGH AS IT MOVES THROUGH THE NRN INTERMOUNTAIN REGION.
TEMPERATURES WILL THEN BEGIN TO REBOUND DURING THE EARLY PORTION OF
NEXT WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS ARE EXPECTED TO CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE TAF PERIOD. HOWEVER...THERE IS A 30
PERCENT CHANCE THAT A LAKE BREEZE COULD PUSH WINDS TO THE WEST-
NORTHWEST BETWEEN 22Z AND 01Z. THERE IS ALSO A 10 PERCENT CHANCE
THAT A SHOWER COULD IMPACT THE TERMINAL THROUGH 03Z...BUT MOST
ACTIVITY SHOULD REMAIN WELL EAST OF KSLC.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA
WILL SERVE AS A FOCUS FOR ISOLATED SHOWERS AND THUNDERSTORMS
ACROSS THE EASTERN HALF OF UTAH THIS EVENING. A DEVELOPING TROUGH
ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN SOUTHWESTERLY
FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY WINDS DURING
THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH. THIS MAY RESULT
IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF FUELS BECOME
SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277.

&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
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000
FXUS65 KSLC 012223
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
423 PM MDT TUE SEP 1 2015

.SYNOPSIS...A MILD SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE
REGION THROUGH THE REMAINDER OF THE WEEK. A PACIFIC TROUGH WILL
MOVE INTO THE GREAT BASIN FOR THE WEEKEND...AND WILL BE
ACCOMPANIED BY A MUCH COOLER...FALL LIKE AIRMASS.

&&

.SHORT TERM (THROUGH 06Z FRIDAY)...SOUTHWESTERLY FLOW ALOFT WILL
PREVAIL ACROSS THE INTERIOR WEST THROUGH THE SHORT TERM
PERIOD...DOWNSTREAM FROM AN UPPER TROUGH WHICH IS FORECAST TO
DEEPEN ALONG THE PACIFIC COAST. DESPITE GRADUAL DRYING OVER THE
PAST COUPLE OF DAYS LINGERING MOISTURE HAS PROVEN SUFFICIENT FOR
ISOLATED CONVECTION ACROSS THE EASTERN TWO THIRDS OF THE FORECAST
AREA THIS AFTERNOON. HAVE MAINTAINED ISOLATED CONVECTION INTO THE
EVENING HOURS ACROSS THE EASTERN HALF OF THE FORECAST AREA.

SOUTHWESTERLY FLOW IS FORECAST TO STRENGTHEN A BIT OVER THE NEXT
COUPLE DAYS RESULTING IN LOCALLY BREEZY CONDITIONS ACROSS WESTERN
UT WHILE MAINTAINING A MILD AIRMASS OVER THE FORECAST AREA. AS THE
AIRMASS CONTINUES TO DRY THE THREAT FOR CONVECTION WILL BE FURTHER
DIMINISHED...AND LIKELY CONFINED ONLY TO THE MOST FAVORABLE AREAS
SUCH AS BOULDER MOUNTAIN AND THE HIGH UINTAS.

WHILE THE OVERALL IDEA OF A STRENGTHENING SOUTHWESTERLY FLOW IS
AGREED UPON BETWEEN THE VARIOUS MODELS...THE DEGREE OF MOISTURE
THURSDAY INTO THURSDAY EVENING REMAINS THE SOURCE OF UNCERTAINTY
WITH THE FORECAST /DISCUSSED IN GREATER DETAIL IN THE LONG TERM
SECTION BELOW/. GIVEN THE AMPLITUDE OF THE UPSTREAM TROUGH SUSPECT
MOISTURE IN AT LEAST A LIMITED CAPACITY WILL MAKE IT INTO SOUTHERN
AND EASTERN PORTIONS OF THE CWA THURSDAY AFTERNOON...AND HAVE
BUMPED POPS 10 TO 20 PERCENT FOR THIS PERIOD.

.LONG TERM (AFTER 06Z FRIDAY)...MEDIUM RANGE MODELS IN GOOD
AGREEMENT WITH THE LARGE SCALE PATTERN INTO THE START OF THE
WEEKEND. AFTER THIS TIME THEY BEGIN TO DIVERGE AND CONFIDENCE IN
THE EVOLUTION OF THE PATTERN DECREASES. PERIOD BEGINS WITH A RIDGE
CENTERED OVER THE CENTRAL U.S. WITH A DEEP TROUGH ALONG THE WEST
COAST. THIS PLACES UTAH UNDER A PRETTY VIGOROUS SW FLOW ALOFT
THURSDAY NIGHT INTO SATURDAY. THE GFS SURGES HIGHER PW AIR INTO
EASTERN UT THU NGT AND DEVELOPS DECENT COVERAGE OF SHOWERS AND
THUNDERSTORMS...PARTICULARLY ACROSS THE ERN PORTION OF THE CWA.
THE CANADIAN AND ECMWF ARE RELUCTANT TO DEVELOP MUCH PRECIP AT
THIS TIME...BUT FEEL THAT THE POTENTIAL IS CERTAINLY THERE TO PULL
DEEPER MOISTURE N AHEAD OF THE APPROACHING FRONT. GIVEN THIS
POTENTIAL WILL INCREASE THE THREAT OF PRECIP JUST A BIT ON THU NGT
AND FRI ACROSS THE ERN HALF OF THE CWA.

EXPECT BREEZY TO WINDY SOUTH WINDS ACROSS MUCH OF THE STATE FRIDAY
AND SATURDAY AHEAD THE COLD FRONT ASSOCIATED WITH THE DEEP WESTERN
TROUGH. THE ECMWF...GFS AND CANADIAN MODELS ALL BRING A SIGNIFICANT
COLD FRONT THROUGH THE STATE SATURDAY NIGHT AND SUNDAY LEADING TO A
SIGNIFICANT COOL DOWN. TEMPERATURES ACROSS THE STATE WILL BE AROUND
15 DEGREES F BELOW NORMAL ON SUNDAY AND SOME AREAS ALONG THE WASATCH
FRONT MAY STRUGGLE TO REACH 70F. THE MEDIUM RANGE MODELS DON/T
DEVELOP MUCH PRECIP ALONG THE FRONT ALTHOUGH BELIEVE IT WILL BE
ACTIVE ACROSS NRN UT CLOSER TO THE LARGE SCALE DYNAMICS ASSOCIATED
WITH THE TROUGH AS IT MOVES THROUGH THE NRN INTERMOUNTAIN REGION.
TEMPERATURES WILL THEN BEGIN TO REBOUND DURING THE EARLY PORTION OF
NEXT WEEK.

&&

.AVIATION...GUSTY SOUTHERLY WINDS ARE EXPECTED TO CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE TAF PERIOD. HOWEVER...THERE IS A 30
PERCENT CHANCE THAT A LAKE BREEZE COULD PUSH WINDS TO THE WEST-
NORTHWEST BETWEEN 22Z AND 01Z. THERE IS ALSO A 10 PERCENT CHANCE
THAT A SHOWER COULD IMPACT THE TERMINAL THROUGH 03Z...BUT MOST
ACTIVITY SHOULD REMAIN WELL EAST OF KSLC.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA
WILL SERVE AS A FOCUS FOR ISOLATED SHOWERS AND THUNDERSTORMS
ACROSS THE EASTERN HALF OF UTAH THIS EVENING. A DEVELOPING TROUGH
ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN SOUTHWESTERLY
FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY WINDS DURING
THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH. THIS MAY RESULT
IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF FUELS BECOME
SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...RED FLAG WARNING UNTIL 9 PM FRIDAY FOR WYZ277.

&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
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000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011608
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1008 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.DISCUSSION...SOUTHWESTERLY FLOW ALOFT PREVAILS ACROSS THE
INTERIOR WEST THIS MORNING...DOWNSTREAM FROM A DEEPENING UPPER
TROUGH SITUATED ALONG THE PACIFIC NORTHWEST COASTLINE. THIS
TROUGH IS DEEPENING IN RESPONSE TO AN EMBEDDED LOW DIGGING ALONG
THE BRITCOL COASTLINE. A WEAK WAVE NOTED IN WV IMAGERY IS LIFTING
THROUGH SOUTHERN AND CENTRAL UT THIS MORNING...HELPING TO DRIVE
ISOLATED SHOWERS AND THUNDERSTORMS ACROSS CENTRAL UT. A WEAK
DEFORMATION AXIS ALONG WITH THIS WAVE APPEARS TO BE ALSO ENHANCING
A MID LEVEL CLOUD DECK ACROSS NORTHERN UT.

GOES DERIVED PW IMAGERY AND REGIONAL 12Z SOUNDINGS INDICATE
DEEPER MOISTURE PRESENT ACROSS AZ NORTHWARD INTO EASTERN
UT...WHILE THE BOUNDARY LAYER ACROSS THE EASTERN GREAT BASIN
REMAINS DRIER WITH PW VALUES LARGELY BELOW 0.5 INCHES. THE
EXCEPTION IS A PLUME OF MID LEVEL MOISTURE WHICH HAS LIFTED INTO
NORTHERN UT THIS MORNING ASSOCIATED WITH THE AFOREMENTIONED WAVE.

AS THIS WAVE CONTINUES NORTHWARD TODAY AND IS COUPLED WITH DAYTIME
HEATING ON THE HIGHER TERRAIN...ANTICIPATE SCATTERED CONVECTION
ALONG THE TERRAIN AND POTENTIALLY SPREAD INTO THE EASTERN VALLEYS.
GIVEN THE AXIS OF MID LEVEL MOISTURE AND WEAK FORCING...COULD
POTENTIALLY SEE SOME OF THIS ACTIVITY SPREAD INTO THE WASATCH
FRONT THIS AFTERNOON...ALTHOUGH MOST RECENT HI-RES CONVECTIVE
ALLOWING MODELS ARE NOT VERY AMBITIOUS WITH THE WESTWARD EXTEND OF
CONVECTION...LARGELY KEEPING ANY ACTIVITY CONFINED TO THE EASTERN
HALF OF THE FORECAST AREA. THIS IS REFLECTED IN THE CURRENT
FORECAST AND WILL HOLD OFF ON UPDATING FOR NOW...BUT KEEP A CLOSE
EYE ON SATELLITE/RADAR TRENDS INTO THE AFTERNOON HOURS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT
KSLC...WITH GUSTY SOUTHERLY WINDS PREVAILING THROUGH THE DAY.
THERE IS A 40 PERCENT CHANCE WIND GUSTS EXCEED 26 KTS AT
TIMES THROUGH THE AFTERNOON...AND A 20 PERCENT CHANCE OF A WIND
SHIFT TO THE NORTHWEST BETWEEN 22-01Z. THERE IS ALSO A 10 PERCENT
CHANCE OF A THUNDERSTORM DEVELOPING OFF THE OQUIRRHS AFTER 19Z AND
IMPACTING THE TERMINAL...WITH THE MAIN THREAT BEING GUSTY ERRATIC
WINDS.

&&

.FIRE WEATHER...A WEAK WEATHER DISTURBANCE CROSSING THE AREA TODAY
WILL SERVE AS A FOCUS FOR SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN HALF OF UTAH THIS AFTERNOON AND EVENING. A DEVELOPING
TROUGH ALONG THE WEST COAST WILL RESULT IN AN INCREASE IN
SOUTHWESTERLY FLOW THROUGH THURSDAY...RESULTING IN GUSTY SOUTHERLY
WINDS DURING THE AFTERNOON...PARTICULARLY ACROSS WESTERN UTAH.
WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS IF
FUELS BECOME SUFFICIENTLY DRY.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...&&

$$

SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011017
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
417 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SATURDAY)...THE UPPER LOW CURRENTLY ALONG
THE CENTRAL BRITCOL COAST WILL CONTINUE ON A SOUTHWARD DRIFT
THROUGH TUESDAY. THIS UPPER LOW WILL EVENTUALLY SETTLE INTO THE
PACIFIC NORTHWEST MIDWEEK///THEN LINGER ACROSS THE NORTHERN HALF
OF THE WESTERN REGION THROUGH THE UPCOMING WEEKEND.

PERSISTENT OVERNIGHT CONVECTION OVER SOUTH-CENTRAL UTAH HAS BEEN
CONFINED TO AN AREA OF LOW-LEVEL CONVERGENCE UNDERNEATH A MODEST
UPPER LEVEL JET ACROSS NORTHERN ARIZONA THROUGH WESTERN COLORADO.
WATER VAPOR IMAGERY SUGGEST A WEAK VORTICITY MAX MAY EXIST OVER
NORTHWEST ARIZONA WHICH IS DRIVING LOOSELY ORGANIZED CONVECTION
ADVANCING INTO EXTREME SOUTHERN UTAH. SUSPECT THIS DYNAMIC FEATURE
WILL USHER THE CONVECTION OFF TO THE EAST AND BRING AN END TO
SHOWERS/STORMS DURING THE MID-MORNING HOURS.

GOES PWAT IMAGERY SHOWS MOISTURE RETURNING NORTH ACROSS WESTERN
UTAH...WITH DEEP LAYER MOISTURE ADVANCING NORTH OUT OF ARIZONA AND
INTO EXTREME SOUTHERN UTAH. CONVECTION WILL LIKELY FORM UP AGAIN
OVER THE HIGHER TERRAIN BEGINNING EARLY THIS AFTERNOON...THEN
CONTINUE ACROSS SOUTHERN THROUGH EAST-CENTRAL UTAH ALONG THE AXIS
OF BEST MOISTURE INTO THIS EVENING. NORTHERN AND WESTERN UTAH
WILL LIKELY SEE AN INCREASE IN CONVECTIVE CLOUD COVER DURING THE
DAY...WITH A MINIMAL CHANCE OF PRECIP AS THE AIR MASS REMAINS LESS
THAN SUPPORTIVE OF DEEP CONVECTION.

LOOKING AT AN INCREASINGLY WARM SOUTHWEST FLOW DEVELOP ACROSS THE
GREAT BASIN IN ADVANCE OF THE PACIFIC NORTHWEST TROUGH MIDWEEK.
BREEZY AND WARM CONDITIONS WILL EXIST ACROSS THE AREA WITH
TERRAIN-BASED CONVECTION ACROSS MAINLY SOUTHERN AND EASTERN UTAH
WITHIN THE DEEP LAYER MOISTURE.

A WELL-DEFINED BAROCLINIC ZONE ASSOCIATED WITH THE UPPER TROUGH WILL
APPROACH NORTHWEST UTAH LATE IN THE WEEK. THIS FEATURE WILL LIKELY
STALL ACROSS FAR NORTHWEST UTAH AND BECOME THE FOCUS FOR SHOWERS
AND STORMS ALONG AND BEHIND THE BOUNDARY. THE VARIOUS MODEL
GUIDANCE ARE NOT GENERATING MUCH IF ANY PRECIP WITH THIS FEATURE
WHICH IS CONCERNING CONSIDERING THE MOISTURE JUST TO THE SOUTH
AND EAST. INCLINED TO THINK THAT SOME PRECIP WILL DEVELOP AS
MOISTURE CONVERGES INTO THE BOUNDARY WITH DYNAMIC LIFT FROM
EJECTING SHORTWAVES OUT OF THE MAIN TROUGH SUPPORTING FAIRLY
DEEP CONVECTION.

.LONG TERM (AFTER 06Z SATURDAY)...GLOBAL MODEL CONSISTENCY HAS
INCREASED A BIT OVER 24 HOURS AGO...WITH THE BULK OF THE 00Z GLOBAL
MODEL GUIDANCE STARTING TO COME MORE TOWARD A COMMON SOLUTION.

A LARGE...RELATIVELY COLD PACIFIC TROUGH WILL BE CROSSING THE
PACIFIC NORTHWEST AT THE START OF THE LONG TERM FORECAST PERIOD.
BOTH THE 00Z GFS AND 00Z EC EJECT THIS TROUGH ACROSS THE NORTHERN
INTERMOUNTAIN REGION AND PERHAPS ACROSS THE NORTHERN GREAT BASIN BY
SUNDAY. TIMING ISSUES REMAIN BETWEEN THESE MODELS...WITH THE GFS
STILL TRENDING FASTER THAN THE EC. THE 00Z CANADIAN HOWEVER...STILL
FAVORS A DEEPER AND SLOWER SYSTEM...WITH THE TROUGH FINALLY EJECTING
SUNDAY AND MOVING INTO SOUTHERN CANADA LATE SUNDAY/EARLY MONDAY.

THERE ARE TWO MAIN DIFFERENCES IN THE EVOLUTION OF THIS TROUGH THAT
DIRECTLY IMPACT UTAH. THE FIRST IS JUST HOW COLD THE SYSTEM WILL BE
AS IT MOVES THROUGH THE AREA. BY SUNDAY MORNING...THE 00Z EC
FEATURES 700MB TEMPERATURES AROUND -2C NEAR THE UTAH/IDAHO
BORDER...WHEREAS THE WARMER GFS AVERAGES NEAR 0C. GIVEN THAT THIS
SYSTEM HAS SLOWED DOWN A BIT FROM EARLIER RUNS...IT APPEARS AS IF
SATURDAY WILL BE A BIT WARMER THAN PREVIOUSLY EXPECTED. INCREASED
TEMPS A BIT ON SATURDAY...AND THESE MAY NEED TO BE ADJUSTED A BIT
WARMER IF THINGS RUN EVEN SLOWER IN LATER MODEL RUNS. KEPT THE TREND
OF LOWERING SUNDAYS HIGHS BELOW CLIMO AS MENTIONED BY PREVIOUS
SHIFTS.

THE OTHER MAIN DIFFERENCE FOR UTAH IS JUST HOW QUICKLY SOUTHERLY
FLOW ADVECTS DEEP MOISTURE INTO UTAH. THE 00Z GFS IS MUCH MORE
PROGRESSIVE WITH THE DEEP MOISTURE SURGE...BRINGING DEEP MOISTURE
INTO THE AREA PRIOR TO THE LONG TERM FORECAST PERIOD. AS THE TROUGH
MOVES INLAND AND THE FLOW BECOMES MORE SOUTHWESTERLY ACROSS MUCH OF
UTAH...THE CHANCE OF PRECIPITATION WILL LIKELY DECREASE BY SATURDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTH.

AFTER THE TROUGH CLEARS THE AREA...THE RIDGE WILL BUILD ONCE AGAIN
ACROSS THE REGION...KEEPING A RELATIVELY BENIGN PATTERN IN
PLACE...WITH WARMING TEMPERATURES THROUGH EARLY NEXT WEEK.

&&

.FIRE WEATHER...A DRIER AND MORE STABLE AIRMASS WILL BUILD INTO THE
AREA TODAY. A LARGE AND FAIRLY STRONG PACIFIC TROUGH WILL SLOWLY
APPROACH THE PACIFIC NORTHWEST OVER THE NEXT SEVERAL DAYS. THIS WILL
INCREASE WINDS ACROSS MUCH OF THE DISTRICT TUESDAY THROUGH THURSDAY.
THIS TROUGH WILL CROSS INTO THE PACIFIC NORTHWEST FRIDAY...AND INTO
THE NORTHERN INTERMOUNTAIN REGION SATURDAY...KEEPING WINDS ELEVATED
THROUGH AT LEAST SATURDAY. OCCASIONAL PERIODS OF LOCALIZED CRITICAL
FIRE WEATHER CONDITIONS WILL BE POSSIBLE TUESDAY THROUGH
SATURDAY...WITH THE BEST CHANCE WEDNESDAY AND THURSDAY.

&&

.AVIATION...ELEVATED SOUTHERLY WINDS WILL CONTINUE AT THE SLC
TERMINAL THROUGH MUCH OF THE DAY. THERE IS A 10 PERCENT CHANCE WINDS
WILL SHIFT TO THE NORTHWEST BETWEEN 21-01Z.

&&


.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.

WY...FIRE WEATHER WATCH FOR WYZ277 FROM 11 AM WEDNESDAY THROUGH
     9 PM FRIDAY.

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 011017
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
417 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SATURDAY)...THE UPPER LOW CURRENTLY ALONG
THE CENTRAL BRITCOL COAST WILL CONTINUE ON A SOUTHWARD DRIFT
THROUGH TUESDAY. THIS UPPER LOW WILL EVENTUALLY SETTLE INTO THE
PACIFIC NORTHWEST MIDWEEK///THEN LINGER ACROSS THE NORTHERN HALF
OF THE WESTERN REGION THROUGH THE UPCOMING WEEKEND.

PERSISTENT OVERNIGHT CONVECTION OVER SOUTH-CENTRAL UTAH HAS BEEN
CONFINED TO AN AREA OF LOW-LEVEL CONVERGENCE UNDERNEATH A MODEST
UPPER LEVEL JET ACROSS NORTHERN ARIZONA THROUGH WESTERN COLORADO.
WATER VAPOR IMAGERY SUGGEST A WEAK VORTICITY MAX MAY EXIST OVER
NORTHWEST ARIZONA WHICH IS DRIVING LOOSELY ORGANIZED CONVECTION
ADVANCING INTO EXTREME SOUTHERN UTAH. SUSPECT THIS DYNAMIC FEATURE
WILL USHER THE CONVECTION OFF TO THE EAST AND BRING AN END TO
SHOWERS/STORMS DURING THE MID-MORNING HOURS.

GOES PWAT IMAGERY SHOWS MOISTURE RETURNING NORTH ACROSS WESTERN
UTAH...WITH DEEP LAYER MOISTURE ADVANCING NORTH OUT OF ARIZONA AND
INTO EXTREME SOUTHERN UTAH. CONVECTION WILL LIKELY FORM UP AGAIN
OVER THE HIGHER TERRAIN BEGINNING EARLY THIS AFTERNOON...THEN
CONTINUE ACROSS SOUTHERN THROUGH EAST-CENTRAL UTAH ALONG THE AXIS
OF BEST MOISTURE INTO THIS EVENING. NORTHERN AND WESTERN UTAH
WILL LIKELY SEE AN INCREASE IN CONVECTIVE CLOUD COVER DURING THE
DAY...WITH A MINIMAL CHANCE OF PRECIP AS THE AIR MASS REMAINS LESS
THAN SUPPORTIVE OF DEEP CONVECTION.

LOOKING AT AN INCREASINGLY WARM SOUTHWEST FLOW DEVELOP ACROSS THE
GREAT BASIN IN ADVANCE OF THE PACIFIC NORTHWEST TROUGH MIDWEEK.
BREEZY AND WARM CONDITIONS WILL EXIST ACROSS THE AREA WITH
TERRAIN-BASED CONVECTION ACROSS MAINLY SOUTHERN AND EASTERN UTAH
WITHIN THE DEEP LAYER MOISTURE.

A WELL-DEFINED BAROCLINIC ZONE ASSOCIATED WITH THE UPPER TROUGH WILL
APPROACH NORTHWEST UTAH LATE IN THE WEEK. THIS FEATURE WILL LIKELY
STALL ACROSS FAR NORTHWEST UTAH AND BECOME THE FOCUS FOR SHOWERS
AND STORMS ALONG AND BEHIND THE BOUNDARY. THE VARIOUS MODEL
GUIDANCE ARE NOT GENERATING MUCH IF ANY PRECIP WITH THIS FEATURE
WHICH IS CONCERNING CONSIDERING THE MOISTURE JUST TO THE SOUTH
AND EAST. INCLINED TO THINK THAT SOME PRECIP WILL DEVELOP AS
MOISTURE CONVERGES INTO THE BOUNDARY WITH DYNAMIC LIFT FROM
EJECTING SHORTWAVES OUT OF THE MAIN TROUGH SUPPORTING FAIRLY
DEEP CONVECTION.

.LONG TERM (AFTER 06Z SATURDAY)...GLOBAL MODEL CONSISTENCY HAS
INCREASED A BIT OVER 24 HOURS AGO...WITH THE BULK OF THE 00Z GLOBAL
MODEL GUIDANCE STARTING TO COME MORE TOWARD A COMMON SOLUTION.

A LARGE...RELATIVELY COLD PACIFIC TROUGH WILL BE CROSSING THE
PACIFIC NORTHWEST AT THE START OF THE LONG TERM FORECAST PERIOD.
BOTH THE 00Z GFS AND 00Z EC EJECT THIS TROUGH ACROSS THE NORTHERN
INTERMOUNTAIN REGION AND PERHAPS ACROSS THE NORTHERN GREAT BASIN BY
SUNDAY. TIMING ISSUES REMAIN BETWEEN THESE MODELS...WITH THE GFS
STILL TRENDING FASTER THAN THE EC. THE 00Z CANADIAN HOWEVER...STILL
FAVORS A DEEPER AND SLOWER SYSTEM...WITH THE TROUGH FINALLY EJECTING
SUNDAY AND MOVING INTO SOUTHERN CANADA LATE SUNDAY/EARLY MONDAY.

THERE ARE TWO MAIN DIFFERENCES IN THE EVOLUTION OF THIS TROUGH THAT
DIRECTLY IMPACT UTAH. THE FIRST IS JUST HOW COLD THE SYSTEM WILL BE
AS IT MOVES THROUGH THE AREA. BY SUNDAY MORNING...THE 00Z EC
FEATURES 700MB TEMPERATURES AROUND -2C NEAR THE UTAH/IDAHO
BORDER...WHEREAS THE WARMER GFS AVERAGES NEAR 0C. GIVEN THAT THIS
SYSTEM HAS SLOWED DOWN A BIT FROM EARLIER RUNS...IT APPEARS AS IF
SATURDAY WILL BE A BIT WARMER THAN PREVIOUSLY EXPECTED. INCREASED
TEMPS A BIT ON SATURDAY...AND THESE MAY NEED TO BE ADJUSTED A BIT
WARMER IF THINGS RUN EVEN SLOWER IN LATER MODEL RUNS. KEPT THE TREND
OF LOWERING SUNDAYS HIGHS BELOW CLIMO AS MENTIONED BY PREVIOUS
SHIFTS.

THE OTHER MAIN DIFFERENCE FOR UTAH IS JUST HOW QUICKLY SOUTHERLY
FLOW ADVECTS DEEP MOISTURE INTO UTAH. THE 00Z GFS IS MUCH MORE
PROGRESSIVE WITH THE DEEP MOISTURE SURGE...BRINGING DEEP MOISTURE
INTO THE AREA PRIOR TO THE LONG TERM FORECAST PERIOD. AS THE TROUGH
MOVES INLAND AND THE FLOW BECOMES MORE SOUTHWESTERLY ACROSS MUCH OF
UTAH...THE CHANCE OF PRECIPITATION WILL LIKELY DECREASE BY SATURDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTH.

AFTER THE TROUGH CLEARS THE AREA...THE RIDGE WILL BUILD ONCE AGAIN
ACROSS THE REGION...KEEPING A RELATIVELY BENIGN PATTERN IN
PLACE...WITH WARMING TEMPERATURES THROUGH EARLY NEXT WEEK.

&&

.FIRE WEATHER...A DRIER AND MORE STABLE AIRMASS WILL BUILD INTO THE
AREA TODAY. A LARGE AND FAIRLY STRONG PACIFIC TROUGH WILL SLOWLY
APPROACH THE PACIFIC NORTHWEST OVER THE NEXT SEVERAL DAYS. THIS WILL
INCREASE WINDS ACROSS MUCH OF THE DISTRICT TUESDAY THROUGH THURSDAY.
THIS TROUGH WILL CROSS INTO THE PACIFIC NORTHWEST FRIDAY...AND INTO
THE NORTHERN INTERMOUNTAIN REGION SATURDAY...KEEPING WINDS ELEVATED
THROUGH AT LEAST SATURDAY. OCCASIONAL PERIODS OF LOCALIZED CRITICAL
FIRE WEATHER CONDITIONS WILL BE POSSIBLE TUESDAY THROUGH
SATURDAY...WITH THE BEST CHANCE WEDNESDAY AND THURSDAY.

&&

.AVIATION...ELEVATED SOUTHERLY WINDS WILL CONTINUE AT THE SLC
TERMINAL THROUGH MUCH OF THE DAY. THERE IS A 10 PERCENT CHANCE WINDS
WILL SHIFT TO THE NORTHWEST BETWEEN 21-01Z.

&&


.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.

WY...FIRE WEATHER WATCH FOR WYZ277 FROM 11 AM WEDNESDAY THROUGH
     9 PM FRIDAY.

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)



000
FXUS65 KSLC 011017
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
417 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SATURDAY)...THE UPPER LOW CURRENTLY ALONG
THE CENTRAL BRITCOL COAST WILL CONTINUE ON A SOUTHWARD DRIFT
THROUGH TUESDAY. THIS UPPER LOW WILL EVENTUALLY SETTLE INTO THE
PACIFIC NORTHWEST MIDWEEK///THEN LINGER ACROSS THE NORTHERN HALF
OF THE WESTERN REGION THROUGH THE UPCOMING WEEKEND.

PERSISTENT OVERNIGHT CONVECTION OVER SOUTH-CENTRAL UTAH HAS BEEN
CONFINED TO AN AREA OF LOW-LEVEL CONVERGENCE UNDERNEATH A MODEST
UPPER LEVEL JET ACROSS NORTHERN ARIZONA THROUGH WESTERN COLORADO.
WATER VAPOR IMAGERY SUGGEST A WEAK VORTICITY MAX MAY EXIST OVER
NORTHWEST ARIZONA WHICH IS DRIVING LOOSELY ORGANIZED CONVECTION
ADVANCING INTO EXTREME SOUTHERN UTAH. SUSPECT THIS DYNAMIC FEATURE
WILL USHER THE CONVECTION OFF TO THE EAST AND BRING AN END TO
SHOWERS/STORMS DURING THE MID-MORNING HOURS.

GOES PWAT IMAGERY SHOWS MOISTURE RETURNING NORTH ACROSS WESTERN
UTAH...WITH DEEP LAYER MOISTURE ADVANCING NORTH OUT OF ARIZONA AND
INTO EXTREME SOUTHERN UTAH. CONVECTION WILL LIKELY FORM UP AGAIN
OVER THE HIGHER TERRAIN BEGINNING EARLY THIS AFTERNOON...THEN
CONTINUE ACROSS SOUTHERN THROUGH EAST-CENTRAL UTAH ALONG THE AXIS
OF BEST MOISTURE INTO THIS EVENING. NORTHERN AND WESTERN UTAH
WILL LIKELY SEE AN INCREASE IN CONVECTIVE CLOUD COVER DURING THE
DAY...WITH A MINIMAL CHANCE OF PRECIP AS THE AIR MASS REMAINS LESS
THAN SUPPORTIVE OF DEEP CONVECTION.

LOOKING AT AN INCREASINGLY WARM SOUTHWEST FLOW DEVELOP ACROSS THE
GREAT BASIN IN ADVANCE OF THE PACIFIC NORTHWEST TROUGH MIDWEEK.
BREEZY AND WARM CONDITIONS WILL EXIST ACROSS THE AREA WITH
TERRAIN-BASED CONVECTION ACROSS MAINLY SOUTHERN AND EASTERN UTAH
WITHIN THE DEEP LAYER MOISTURE.

A WELL-DEFINED BAROCLINIC ZONE ASSOCIATED WITH THE UPPER TROUGH WILL
APPROACH NORTHWEST UTAH LATE IN THE WEEK. THIS FEATURE WILL LIKELY
STALL ACROSS FAR NORTHWEST UTAH AND BECOME THE FOCUS FOR SHOWERS
AND STORMS ALONG AND BEHIND THE BOUNDARY. THE VARIOUS MODEL
GUIDANCE ARE NOT GENERATING MUCH IF ANY PRECIP WITH THIS FEATURE
WHICH IS CONCERNING CONSIDERING THE MOISTURE JUST TO THE SOUTH
AND EAST. INCLINED TO THINK THAT SOME PRECIP WILL DEVELOP AS
MOISTURE CONVERGES INTO THE BOUNDARY WITH DYNAMIC LIFT FROM
EJECTING SHORTWAVES OUT OF THE MAIN TROUGH SUPPORTING FAIRLY
DEEP CONVECTION.

.LONG TERM (AFTER 06Z SATURDAY)...GLOBAL MODEL CONSISTENCY HAS
INCREASED A BIT OVER 24 HOURS AGO...WITH THE BULK OF THE 00Z GLOBAL
MODEL GUIDANCE STARTING TO COME MORE TOWARD A COMMON SOLUTION.

A LARGE...RELATIVELY COLD PACIFIC TROUGH WILL BE CROSSING THE
PACIFIC NORTHWEST AT THE START OF THE LONG TERM FORECAST PERIOD.
BOTH THE 00Z GFS AND 00Z EC EJECT THIS TROUGH ACROSS THE NORTHERN
INTERMOUNTAIN REGION AND PERHAPS ACROSS THE NORTHERN GREAT BASIN BY
SUNDAY. TIMING ISSUES REMAIN BETWEEN THESE MODELS...WITH THE GFS
STILL TRENDING FASTER THAN THE EC. THE 00Z CANADIAN HOWEVER...STILL
FAVORS A DEEPER AND SLOWER SYSTEM...WITH THE TROUGH FINALLY EJECTING
SUNDAY AND MOVING INTO SOUTHERN CANADA LATE SUNDAY/EARLY MONDAY.

THERE ARE TWO MAIN DIFFERENCES IN THE EVOLUTION OF THIS TROUGH THAT
DIRECTLY IMPACT UTAH. THE FIRST IS JUST HOW COLD THE SYSTEM WILL BE
AS IT MOVES THROUGH THE AREA. BY SUNDAY MORNING...THE 00Z EC
FEATURES 700MB TEMPERATURES AROUND -2C NEAR THE UTAH/IDAHO
BORDER...WHEREAS THE WARMER GFS AVERAGES NEAR 0C. GIVEN THAT THIS
SYSTEM HAS SLOWED DOWN A BIT FROM EARLIER RUNS...IT APPEARS AS IF
SATURDAY WILL BE A BIT WARMER THAN PREVIOUSLY EXPECTED. INCREASED
TEMPS A BIT ON SATURDAY...AND THESE MAY NEED TO BE ADJUSTED A BIT
WARMER IF THINGS RUN EVEN SLOWER IN LATER MODEL RUNS. KEPT THE TREND
OF LOWERING SUNDAYS HIGHS BELOW CLIMO AS MENTIONED BY PREVIOUS
SHIFTS.

THE OTHER MAIN DIFFERENCE FOR UTAH IS JUST HOW QUICKLY SOUTHERLY
FLOW ADVECTS DEEP MOISTURE INTO UTAH. THE 00Z GFS IS MUCH MORE
PROGRESSIVE WITH THE DEEP MOISTURE SURGE...BRINGING DEEP MOISTURE
INTO THE AREA PRIOR TO THE LONG TERM FORECAST PERIOD. AS THE TROUGH
MOVES INLAND AND THE FLOW BECOMES MORE SOUTHWESTERLY ACROSS MUCH OF
UTAH...THE CHANCE OF PRECIPITATION WILL LIKELY DECREASE BY SATURDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTH.

AFTER THE TROUGH CLEARS THE AREA...THE RIDGE WILL BUILD ONCE AGAIN
ACROSS THE REGION...KEEPING A RELATIVELY BENIGN PATTERN IN
PLACE...WITH WARMING TEMPERATURES THROUGH EARLY NEXT WEEK.

&&

.FIRE WEATHER...A DRIER AND MORE STABLE AIRMASS WILL BUILD INTO THE
AREA TODAY. A LARGE AND FAIRLY STRONG PACIFIC TROUGH WILL SLOWLY
APPROACH THE PACIFIC NORTHWEST OVER THE NEXT SEVERAL DAYS. THIS WILL
INCREASE WINDS ACROSS MUCH OF THE DISTRICT TUESDAY THROUGH THURSDAY.
THIS TROUGH WILL CROSS INTO THE PACIFIC NORTHWEST FRIDAY...AND INTO
THE NORTHERN INTERMOUNTAIN REGION SATURDAY...KEEPING WINDS ELEVATED
THROUGH AT LEAST SATURDAY. OCCASIONAL PERIODS OF LOCALIZED CRITICAL
FIRE WEATHER CONDITIONS WILL BE POSSIBLE TUESDAY THROUGH
SATURDAY...WITH THE BEST CHANCE WEDNESDAY AND THURSDAY.

&&

.AVIATION...ELEVATED SOUTHERLY WINDS WILL CONTINUE AT THE SLC
TERMINAL THROUGH MUCH OF THE DAY. THERE IS A 10 PERCENT CHANCE WINDS
WILL SHIFT TO THE NORTHWEST BETWEEN 21-01Z.

&&


.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.

WY...FIRE WEATHER WATCH FOR WYZ277 FROM 11 AM WEDNESDAY THROUGH
     9 PM FRIDAY.

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




000
FXUS65 KSLC 011017
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
417 AM MDT TUE SEP 1 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH DEVELOPING OVER WESTERN CANADA
WILL SETTLE SOUTH INTO THE PACIFIC NORTHWEST MIDWEEK. A MOSTLY DRY
AND WARM SOUTHWEST FLOW ALOFT WILL FORM ACROSS THE GREAT BASIN...
FOLLOWED BY COOLER FALL LIKE TEMPERATURES SPREADING ACROSS THE
REGION OVER THE WEEKEND.

&&

.SHORT TERM (UNTIL 06Z SATURDAY)...THE UPPER LOW CURRENTLY ALONG
THE CENTRAL BRITCOL COAST WILL CONTINUE ON A SOUTHWARD DRIFT
THROUGH TUESDAY. THIS UPPER LOW WILL EVENTUALLY SETTLE INTO THE
PACIFIC NORTHWEST MIDWEEK///THEN LINGER ACROSS THE NORTHERN HALF
OF THE WESTERN REGION THROUGH THE UPCOMING WEEKEND.

PERSISTENT OVERNIGHT CONVECTION OVER SOUTH-CENTRAL UTAH HAS BEEN
CONFINED TO AN AREA OF LOW-LEVEL CONVERGENCE UNDERNEATH A MODEST
UPPER LEVEL JET ACROSS NORTHERN ARIZONA THROUGH WESTERN COLORADO.
WATER VAPOR IMAGERY SUGGEST A WEAK VORTICITY MAX MAY EXIST OVER
NORTHWEST ARIZONA WHICH IS DRIVING LOOSELY ORGANIZED CONVECTION
ADVANCING INTO EXTREME SOUTHERN UTAH. SUSPECT THIS DYNAMIC FEATURE
WILL USHER THE CONVECTION OFF TO THE EAST AND BRING AN END TO
SHOWERS/STORMS DURING THE MID-MORNING HOURS.

GOES PWAT IMAGERY SHOWS MOISTURE RETURNING NORTH ACROSS WESTERN
UTAH...WITH DEEP LAYER MOISTURE ADVANCING NORTH OUT OF ARIZONA AND
INTO EXTREME SOUTHERN UTAH. CONVECTION WILL LIKELY FORM UP AGAIN
OVER THE HIGHER TERRAIN BEGINNING EARLY THIS AFTERNOON...THEN
CONTINUE ACROSS SOUTHERN THROUGH EAST-CENTRAL UTAH ALONG THE AXIS
OF BEST MOISTURE INTO THIS EVENING. NORTHERN AND WESTERN UTAH
WILL LIKELY SEE AN INCREASE IN CONVECTIVE CLOUD COVER DURING THE
DAY...WITH A MINIMAL CHANCE OF PRECIP AS THE AIR MASS REMAINS LESS
THAN SUPPORTIVE OF DEEP CONVECTION.

LOOKING AT AN INCREASINGLY WARM SOUTHWEST FLOW DEVELOP ACROSS THE
GREAT BASIN IN ADVANCE OF THE PACIFIC NORTHWEST TROUGH MIDWEEK.
BREEZY AND WARM CONDITIONS WILL EXIST ACROSS THE AREA WITH
TERRAIN-BASED CONVECTION ACROSS MAINLY SOUTHERN AND EASTERN UTAH
WITHIN THE DEEP LAYER MOISTURE.

A WELL-DEFINED BAROCLINIC ZONE ASSOCIATED WITH THE UPPER TROUGH WILL
APPROACH NORTHWEST UTAH LATE IN THE WEEK. THIS FEATURE WILL LIKELY
STALL ACROSS FAR NORTHWEST UTAH AND BECOME THE FOCUS FOR SHOWERS
AND STORMS ALONG AND BEHIND THE BOUNDARY. THE VARIOUS MODEL
GUIDANCE ARE NOT GENERATING MUCH IF ANY PRECIP WITH THIS FEATURE
WHICH IS CONCERNING CONSIDERING THE MOISTURE JUST TO THE SOUTH
AND EAST. INCLINED TO THINK THAT SOME PRECIP WILL DEVELOP AS
MOISTURE CONVERGES INTO THE BOUNDARY WITH DYNAMIC LIFT FROM
EJECTING SHORTWAVES OUT OF THE MAIN TROUGH SUPPORTING FAIRLY
DEEP CONVECTION.

.LONG TERM (AFTER 06Z SATURDAY)...GLOBAL MODEL CONSISTENCY HAS
INCREASED A BIT OVER 24 HOURS AGO...WITH THE BULK OF THE 00Z GLOBAL
MODEL GUIDANCE STARTING TO COME MORE TOWARD A COMMON SOLUTION.

A LARGE...RELATIVELY COLD PACIFIC TROUGH WILL BE CROSSING THE
PACIFIC NORTHWEST AT THE START OF THE LONG TERM FORECAST PERIOD.
BOTH THE 00Z GFS AND 00Z EC EJECT THIS TROUGH ACROSS THE NORTHERN
INTERMOUNTAIN REGION AND PERHAPS ACROSS THE NORTHERN GREAT BASIN BY
SUNDAY. TIMING ISSUES REMAIN BETWEEN THESE MODELS...WITH THE GFS
STILL TRENDING FASTER THAN THE EC. THE 00Z CANADIAN HOWEVER...STILL
FAVORS A DEEPER AND SLOWER SYSTEM...WITH THE TROUGH FINALLY EJECTING
SUNDAY AND MOVING INTO SOUTHERN CANADA LATE SUNDAY/EARLY MONDAY.

THERE ARE TWO MAIN DIFFERENCES IN THE EVOLUTION OF THIS TROUGH THAT
DIRECTLY IMPACT UTAH. THE FIRST IS JUST HOW COLD THE SYSTEM WILL BE
AS IT MOVES THROUGH THE AREA. BY SUNDAY MORNING...THE 00Z EC
FEATURES 700MB TEMPERATURES AROUND -2C NEAR THE UTAH/IDAHO
BORDER...WHEREAS THE WARMER GFS AVERAGES NEAR 0C. GIVEN THAT THIS
SYSTEM HAS SLOWED DOWN A BIT FROM EARLIER RUNS...IT APPEARS AS IF
SATURDAY WILL BE A BIT WARMER THAN PREVIOUSLY EXPECTED. INCREASED
TEMPS A BIT ON SATURDAY...AND THESE MAY NEED TO BE ADJUSTED A BIT
WARMER IF THINGS RUN EVEN SLOWER IN LATER MODEL RUNS. KEPT THE TREND
OF LOWERING SUNDAYS HIGHS BELOW CLIMO AS MENTIONED BY PREVIOUS
SHIFTS.

THE OTHER MAIN DIFFERENCE FOR UTAH IS JUST HOW QUICKLY SOUTHERLY
FLOW ADVECTS DEEP MOISTURE INTO UTAH. THE 00Z GFS IS MUCH MORE
PROGRESSIVE WITH THE DEEP MOISTURE SURGE...BRINGING DEEP MOISTURE
INTO THE AREA PRIOR TO THE LONG TERM FORECAST PERIOD. AS THE TROUGH
MOVES INLAND AND THE FLOW BECOMES MORE SOUTHWESTERLY ACROSS MUCH OF
UTAH...THE CHANCE OF PRECIPITATION WILL LIKELY DECREASE BY SATURDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTH.

AFTER THE TROUGH CLEARS THE AREA...THE RIDGE WILL BUILD ONCE AGAIN
ACROSS THE REGION...KEEPING A RELATIVELY BENIGN PATTERN IN
PLACE...WITH WARMING TEMPERATURES THROUGH EARLY NEXT WEEK.

&&

.FIRE WEATHER...A DRIER AND MORE STABLE AIRMASS WILL BUILD INTO THE
AREA TODAY. A LARGE AND FAIRLY STRONG PACIFIC TROUGH WILL SLOWLY
APPROACH THE PACIFIC NORTHWEST OVER THE NEXT SEVERAL DAYS. THIS WILL
INCREASE WINDS ACROSS MUCH OF THE DISTRICT TUESDAY THROUGH THURSDAY.
THIS TROUGH WILL CROSS INTO THE PACIFIC NORTHWEST FRIDAY...AND INTO
THE NORTHERN INTERMOUNTAIN REGION SATURDAY...KEEPING WINDS ELEVATED
THROUGH AT LEAST SATURDAY. OCCASIONAL PERIODS OF LOCALIZED CRITICAL
FIRE WEATHER CONDITIONS WILL BE POSSIBLE TUESDAY THROUGH
SATURDAY...WITH THE BEST CHANCE WEDNESDAY AND THURSDAY.

&&

.AVIATION...ELEVATED SOUTHERLY WINDS WILL CONTINUE AT THE SLC
TERMINAL THROUGH MUCH OF THE DAY. THERE IS A 10 PERCENT CHANCE WINDS
WILL SHIFT TO THE NORTHWEST BETWEEN 21-01Z.

&&


.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.

WY...FIRE WEATHER WATCH FOR WYZ277 FROM 11 AM WEDNESDAY THROUGH
     9 PM FRIDAY.

&&

$$

CONGER/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)




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