Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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000
FXUS65 KSLC 291138
AFDSLC
AFDSLC

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
538 AM MDT FRI MAY 29 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL STRENGTHEN ACROSS THE
INTERIOR WEST...RESULTING IN A SUBSTANTIAL WARMING AND DRYING
TREND ACROSS THE ENTIRE REGION THROUGH THE UPCOMING WEEKEND.

&&

.SHORT TERM (THROUGH 06Z TUESDAY)...THE AXIS OF THE UPPER RIDGE
CURRENTLY ALONG THE WEST COAST WILL SHIFT EAST INTO THE WESTERN
GREAT BASIN LATER TODAY. FROM THERE THE UPPER RIDGE WILL SHIFT
EAST AND STRENGTHEN ACROSS THE INTERIOR WEST THIS WEEKEND. A
SUBSTANTIAL WARMING A DRYING TREND IS ANTICIPATED AREA WIDE
THROUGH AT LEAST SUNDAY.

AHEAD OF THE ADVANCING UPPER RIDGE A STILL SOMEWHAT MOIST CYCLONIC
NORTHWEST FLOW ALOFT WILL BRING ANOTHER CHANCE FOR SHOWERS/STORMS
THROUGH EARLY THIS EVENING. THE BEST AREAS FOR CONVECTIVE PRECIP
WILL BE ACROSS THE SOUTHERN THIRD OF THE STATE WHERE WEAK DYNAMIC
SUPPORT EXISTS...AND ACROSS FAR NORTHERN AND NORTHEAST UTAH WHERE
ONE LAST VORTICITY LOBE WILL ROTATE SOUTHEAST ACROSS THE REGION
BEHIND THE EXITING UPPER LOW HEADING INTO THE NORTHERN/CENTRAL
PLAINS STATES.

A MID-LEVEL MOISTURE TAP POURING INTO THE STRENGTHENING RIDGE WILL
SUPPORT HIGH-BASED CONVECTION AGAIN ON SATURDAY. MODEL GUIDANCE
HINTS THAT A WEAK SHORTWAVE AHEAD OF THE UPPER RIDGE WILL
ACCOMPANY THIS MOISTURE SATURDAY AFTERNOON. THIS FEATURE COULD
BRING SOME ORGANIZATION TO THE CONVECTION WITH AN INCREASE IN
AREAL COVERAGE BEYOND TERRAIN-BASED CONVECTION POSSIBLE.

FURTHER STRENGTHENING OF THE UPPER RIDGE SUNDAY SHOULD DRIVE THE
BULK OF THE MOISTURE NORTH OF THE STATE...LEADING TO MAINLY
ISOLATED TERRAIN-BASED CONVECTION SUNDAY AFTERNOON/EARLY EVENING.
INCREASING SOUTHWEST FLOW ACROSS WESTERN UTAH DURING THE DAY WILL
DRIVE TEMPERATURES UPWARD...WITH READINGS ENDING UP WELL ABOVE
NORMAL FOR THE END OF MAY. FURTHER INCREASES IN THE NEAR 700 MB
WINDS AND TEMPS WILL BRING THE WARMEST TEMPERATURES OF THE YEAR TO
MUCH OF THE STATE SUNDAY.

A WEAK SHORTWAVE EJECTING OUT AHEAD OFT EH UPPER TROUGH OFF THE
PACIFIC NORTHWEST WILL DRIVE A COLD FRONT INTO NORTHWEST UTAH
MONDAY. COOLER TEMPS AND A FEW SHOWERS/STORMS WILL EXIST NEAR THE
FRONT ACROSS THE NORTH MONDAY AFTERNOON. POINTS SOUTH OF THE
FRONT WILL REMAIN WINDY AND QUITE WARM MONDAY AFTERNOON/EVENING.

.LONG TERM (AFTER 06Z TUESDAY)...YET ANOTHER LONG WAVE TROUGH WILL
BECOME ESTABLISHED ACROSS THE WESTERN CONUS BEGINNING TUESDAY...
THOUGH AXIS WILL REMAIN WELL WEST AND NORTH OF THE AREA ALLOWING
A MOSTLY DRY CYCLONIC SOUTHWESTERLY FLOW TO DOMINATE INTO
WEDNESDAY. ONE OF SEVERAL SHORT WAVES ROTATING AROUND THE BASE OF
THE TROUGH WILL CARVE A BIT FURTHER EAST WEDNESDAY ALLOW PASSAGE
OF A SHALLOW COLD FRONT ACROSS THE NORTHERN HALF OF THE AREA BY
LATE DAY. EXPECTING JUST ENOUGH MOISTURE/FORCING/INSTABILITY TO
GENERATE ISOLATED TO WIDELY SCATTERED CONVECTION ALONG AND BEHIND
THIS FEATURE...BUT BULK OF STORMS SHOULD BE OF THE GUSTY WIND
VARIETY WITH MINIMAL PRECIP. THIS BOUNDARY COULD BECOME A FOCUS
FOR FURTHER CONVECTION LATE WEEK AS THE PARENT TROUGH MOVES
THROUGH THE AREA...BUT INCREASED SPREAD EXISTS IN GLOBAL GUIDANCE
REGARDING AND TRACK AND EVOLUTION OF THIS FEATURE.

REGARDING TEMPERATURES...WARMEST EARLY IN THE PERIOD THEN COOLING
BACK TO NEAR NORMAL VALUES MID/LATE WEEK.


&&

.FIRE WEATHER...REMNANT LOW AND MID LEVEL MOISTURE IN WAKE OF THE
DEPARTING TROUGH WILL CONTINUE TO ALLOW FOR ISOLATED TO WIDELY
SCATTERED CONVECTION OVER THE HIGHER TERRAIN OF THE SOUTHERN
MOUNTAINS AND THE NORTHEAST TODAY...BUT AS A WHOLE THE
DRYING/WARMING TREND WILL BEGIN IN EARNEST THIS AFTERNOON.

HIGH PRESSURE BUILDING INTO THE EASTERN GREAT BASIN WILL ALLOW FOR A
MARKED WARMING/DRYING TREND INTO EARLY NEXT WEEK. THE APPROACH OF
YET ANOTHER PACIFIC TROUGH WILL AID TO CREATE BREEZY SOUTHERLY WINDS
BEGINNING SUNDAY...AND COMBINED WITH VERY LOW RH AT THAT TIME
CRITICAL METEOROLOGICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS
THE WESTERN VALLEYS. SLOW MOVING NATURE OF THIS TROUGH AND
ASSOCIATED COLD FRONT WILL AID TO MAINTAIN THESE CONDITIONS THROUGH
TUESDAY.

THE SHALLOW COLD FRONT WILL MOVE THROUGH NORTHERN UTAH MIDWEEK
ALLOWING COVERAGE OF SHOWERS/STORMS TO INCREASE ONCE AGAIN...BUT NOT
TO THE LEVEL EXPERIENCED AS OF LATE.

&&

.AVIATION...OPERATIONAL WEATHER CONCERNS ARE EXPECTED TO REMAIN
MINIMAL AT THE KSLC TERMINAL THROUGH THE VALID TAF PERIOD. LIGHT
SOUTHEASTERLY SURFACE WINDS ARE EXPECTED TO SWITCH TO THE NORTHWEST
BETWEEN 18-19Z PER NORM...AND SKIES WILL REMAIN LARGELY CLEAR.

&&


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

$$

SHORT TERM...CONGER
LONG TERM/FIRE WEATHER/AVIATION...MERRILL

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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