AREA FORECAST DISCUSSION

 
 FXUS65 KSLC 092054
 AFDSLC
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SALT LAKE CITY UT
 254 PM MDT THU SEP 9 2010
 
 .SYNOPSIS...A COOL PACIFIC TROUGH WILL LIFT THROUGH THE STATE
 THROUGH FRIDAY MORNING. HIGH PRESSURE WILL BUILD THROUGH THE
 WEEKEND WITH DRIER WESTERLY FLOW DOMINATING THROUGH MIDWEEK OF
 NEXT WEEK.
 
 
 
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 .DISCUSSION...AFTERNOON SATELLITE LOOPS SHOW PACIFIC TROUGH
 LIFTING NORTHEAST THROUGH THE GREAT BASIN/NORTHERN ROCKIES STATES.
 SAID TROUGH EXHIBITS TWO PRONOUNCED SHORT WAVES...WITH FIRST
 LIFTING THROUGH CENTRAL IDAHO...AND A TRAILING COLD POCKET
 DROPPING SOUTHEAST THROUGH EASTERN OREGON. INITIAL WAVE WAS
 RESPONSIBLE FOR SURGING THE LEADING EDGE COLD FRONT THROUGH THE
 WASATCH FRONT THIS MORNING SPREADING NUMEROUS SHOWERS AND STORMS
 ACROSS THE METRO AREA. THE FRONT CURRENTLY REMAINS STALLED ACROSS
 SOUTHERN UTAH VALLEY WITH DRY AND GUSTY SOUTHWESTERLY FLOW
 DOMINATING CENTRAL AND SOUTHERN PORTIONS OF THE STATE. STALLED
 NATURE OF THE FRONT HAS ALLOWED FOR A SUBSIDENT AIRMASS ACROSS THE
 CENTRAL WASATCH...SQUELCHING MOST ALL AFTERNOON SHOWER DEVELOPMENT
 SOUTH OF OGDEN. AREAS NORTH OF OGDEN REMAIN MORE BUOYANT AS MID
 LEVEL BAROCLINIC ZONE PASSES THROUGH THE EAST. SCATTERED SHOWERS
 AND ISOLATED STORMS REMAINING ALONG THE UT/ID BORDER.
 
 AFOREMENTIONED UPSTREAM SHORT WAVE WILL CARVE THE TROUGH SOUTH A
 BIT AFTER MIDNIGHT TONIGHT...SURGING THE STALLED SURFACE BOUNDARY
 INTO SOUTH CENTRAL UTAH BY DAWN FRIDAY. MODEL SUITE CONSISTENT IN
 REGENERATING PRECIP ACROSS THE WASATCH FRONT/MOUNTAINS AS THIS
 OCCURS...WITH SHOWERS AND EVEN SOME SNOW POSSIBLE ACROSS THE
 CENTRAL/NORTHERN WASATCH MOUNTAINS ABOVE 75-8000 FT EARLY FRIDAY
 MORNING. THIS IDEA SEEMS REALISTIC. SUBSIDENCE WILL WANE ACROSS
 THE NORTH AS FRONTAL BOUNDARY FINALLY TRACKS SOUTH...AND MID LEVEL
 COLD POCKET WILL ALLOW WEAK COLD ADVECTION INCREASING INSTABILITY
 ACROSS THE NORTH. PVA ASSOCIATED WITH UPSTREAM SHORT WAVE TO
 INITIATE SHOWERS. KEPT SCATTERED TO NUMEROUS SHOWERS IN FORECAST
 FOR LATE NIGHT WITH MUCH COOLER TEMPS.
 
 CLEARING AND DRYING CONDITIONS EXPECTED ALL AREAS BY MIDDAY
 FRIDAY. PACIFIC TROUGH WILL LIFT OFF RAPIDLY TO THE NORTHEAST
 ALLOWING RAPID HEIGHT RISES AS SHORT WAVE RIDGING ENTRENCHES IN
 THE GREAT BASIN STARTING FRIDAY NIGHT. ANOTHER COOL NIGHT EXPECTED
 FRIDAY NIGHT AS A RESULT...ESPECIALLY FOR MOUNTAIN VALLEY AREAS.
 ADDED MENTION OF PATCHY FROST THROUGH THE BEAR RIVER VALLEY AND
 WASATCH BACK.
 
 AFOREMENTIONED RIDGE WILL HOLD STRONG THROUGH EARLY NEXT WEEK. TEMP
 TRENDS TO CLIMB RAPIDLY BACK TOWARDS CLIMO...EXCEEDING NORMS BY EARLY
 NEXT WEEK IN SOME LOCALS.
 
 &&
 
 .AVIATION...THERE IS A 30 PERCENT CHANCE OF SHOWERS IMPACTING THE 
 SLC TERMINAL THROUGH THE EVENING AND OVERNIGHT HOURS...WITH CEILINGS 
 BELOW 7000FT AGL POSSIBLE IN ANY SHOWERS. GUSTY NORTHWEST SURFACE 
 WINDS ARE EXPECTED TO WEAKEN THROUGH THE EVENING...THEN RETURN TO 
 THE SOUTH BETWEEN 04Z AND 06Z...WITH A SLIGHT CHANCE THAT WINDS 
 REMAIN NORTHWESTERLY THROUGH 07Z.  
 
 &&
 
 .FIRE WEATHER...THE PACIFIC TROUGH CONTINUES TO MOVE THROUGH 
 NORTHERN UTAH AND IS PULLING OFF TO THE NORTHEAST. THE ASSOCIATED 
 COLD FRONT HAS PUSHED INTO CENTRAL UTAH AND WILL MAKE LITTLE FARTHER 
 PROGRESS SOUTH. SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS 
 AFTERNOON AND EVENING WITH ANOTHER FAIR SHOT FOR NOCTURNAL 
 CONVECTION FRIDAY MORNING WHEN THE COLDEST AIR AND ANOTHER WEAK WAVE 
 ARRIVES OVER THE NORTHERN PORTION OF THE FIRE DISTRICT. MUCH COOLER 
 TEMPERATURES ALONG WITH WETTING RAINS CAN BE EXPECTED THROUGH FRIDAY 
 MORNING OVER THE NORTH. AHEAD OF THIS FRONT...OVER THE SOUTHERN HALF 
 OF THE DISTRICT...GUSTY SOUTHWEST WINDS ALONG WITH MILD TEMPERATURES 
 CAN BE EXPECTED TONIGHT AND FRIDAY. ISOLATED CRITICAL FIRE WEATHER 
 CONDITIONS POSSIBLE ACROSS SOUTHEAST UTAH...BUT ONLY BORDERLINE WITH 
 NO WARNINGS ANTICIPATED. WINDS WILL CONTINUE TO RELAX OVER THE NEXT 
 SEVERAL DAYS AS A RIDGE OF HIGH PRESSURE SETTLES OVER THE AREA. THIS 
 WILL USHER IN A DRY AND MILD WESTERLY FLOW AND A WARMING AND DRYING 
 TREND THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
 
 &&
 
 .SLC WATCHES/WARNINGS/ADVISORIES...
 UT...NONE.
 WY...NONE.
 &&
 
 $$
 
 PUBLIC...MERRILL
 FIRE WEATHER...YOUNG
 AVIATION...SCHOENING
 
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 HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)
 
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 VISIT...
 HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)