Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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000
FXUS65 KSLC 261126
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
526 AM MDT FRI SEP 26 2014

.SYNOPSIS...A MILD SOUTHWESTERLY FLOW WILL REMAIN OVER THE AREA
TODAY. A COOL PACIFIC SYSTEM WILL MOVE INLAND TONIGHT AND SLOWLY
CROSS THE GREAT BASIN SATURDAY THROUGH MONDAY.

&&

.DISCUSSION...UTAH REMAINS UNDER A WARM SOUTHWESTERLY FLOW THIS
MORNING AHEAD OF A STORM SYSTEM APPROACHING FROM THE WEST. MOSTLY
CLEAR SKIES REMAIN IN PLACE THIS MORNING...ALTHOUGH CLOUDS ARE
EXPECTED TO INCREASE THROUGH THE DAY. OTHERWISE...A SOUTHERLY
SURFACE PRESSURE GRADIENT EXTENDING FROM NORTH-CENTRAL THROUGH
SOUTHWEST UTAH IS RESPONSIBLE FOR INCREASED SOUTHERLY WINDS ACROSS
THE WESTERN VALLEYS. THESE WINDS SHOULD FURTHER STRENGTHEN THIS
AFTERNOON AS MIXING BECOMES ENHANCED. ALTHOUGH TEMPERATURES WILL BE
A BIT COOLER TODAY AS H7 TEMPERATURES FALL A COUPLE OF DEGREES...THE
SOUTH WINDS SHOULD KEEP ALL AREAS WELL ABOVE CLIMO TODAY.

THE STORM SYSTEM OVER THE WEST COAST HAS ALREADY EJECTED A PIECE OF
ENERGY ACROSS EASTERN OREGON AND WESTERN IDAHO. THIS PRODUCED SOME
PRECIPITATION OVER NEVADA OVERNIGHT BUT SINCE THIS WAVE WILL
CONTINUE TO LIFT NORTHEAST IT WILL NOT BE A CONCERN FOR OUR AREA.
INSTEAD...MOISTURE IS INCREASING FROM THE SOUTH AND SOUTHWEST
WHICH...WHEN COMBINED WITH INCREASING INSTABILITY...WILL ALLOW A FEW
SHOWERS AND THUNDERSTORMS TO DEVELOP OVER THE FORECAST AREA THIS
AFTERNOON. WITH PWATS FORECAST TO INCREASE TO AROUND AN INCH...SOME
OF THE STORMS COULD PRODUCE LOCALLY HEAVY RAIN.

THE PART OF THE STORM THAT CONCERNS US IS CURRENTLY PINCHING OFF
INTO A CLOSED LOW AND APPROACHING THE SF BAY AREA. THIS WILL
CONTINUE TO SPIN UP AND SLOWLY TRACK ACROSS THE SIERRA NEVADA
TONIGHT. IN DOING SO...INCREASING DIFFLUENT FLOW AHEAD OF THIS
APPROACHING LOW WILL CAUSE PRECIPITATION TO INCREASE OVER UTAH FROM
THE WEST TONIGHT. THE HEAVIEST AND MOST WIDESPREAD PRECIPITATION
WILL OCCUR DURING THE DAY TOMORROW AS A COLD FRONT PUSHES ACROSS THE
AREA FROM THE WEST-SOUTHWEST. WITH LARGE-SCALE LIFT COMBINED WITH
SOME INSTABILITY AND THE AMPLE MOISTURE IN PLACE...EXPECT SOME AREAS
TO SEE HEAVY PRECIPITATION TOMORROW. MAY NEED TO CONSIDER SOME HYDRO
HIGHLIGHTS...BUT WILL LET THE DAY SHIFT MAKE THE DECISION SINCE THE
EVENT IS STILL AROUND 24 HOURS OUT.

A DRY SLOT WILL PUNCH INTO THE AREA BEHIND THE FRONT SO EXPECT
PRECIPITATION TO WIND DOWN ACROSS SOUTHERN UTAH FROM WEST TO EAST
TOMORROW NIGHT. AS THE LOW CONTINUES TO SLOWLY TRACK ACROSS THE
AREA...INSTABILITY SHOWERS WILL CONTINUE ON SUNDAY WITH SOME LOCALLY
ENHANCED ACTIVITY AS VARIOUS EMBEDDED DISTURBANCES ROTATE AROUND THE
LOW CENTER. LINGERING SHOWERS WILL CONTINUE ACROSS THE NORTH ON
MONDAY AS MOISTURE CONTINUES TO WRAP AROUND THE DEPARTING LOW.

MUCH COOLER TEMPERATURES ARE STILL PROGGED TO ACCOMPANY THIS STORM
SYSTEM. A NOTICEABLE DROP IN TEMPERATURES WILL OCCUR TOMORROW...WITH
MANY AREAS BECOMING 5-10 DEGREES BELOW CLIMO FOR SUNDAY AND MONDAY.
ALL TOLD...THIS IS SHAPING UP TO BE QUITE A SOAKER WITH MODELS
DEPICTING OVER 1 INCH STORM TOTALS ACROSS MANY AREAS...PEAKING
GREATER THAN 2 INCHES IN SOME AREAS. WITH THE ARRIVAL OF COLDER
TEMPERATURES...ACCUMULATING SNOW IS EXPECTED ON THE HIGHER PEAKS.
ALTHOUGH THERE IS STILL SOME SPREAD IN H7 TEMPERATURES BETWEEN THE
VARIOUS MODELS...MOST OF THE SNOW WILL LIKELY OCCUR ABOVE 9KFT
BEGINNING LATE SUNDAY.

ANOTHER STORM SYSTEM IS STILL IN THE PICTURE FOR TUESDAY NIGHT AND
WEDNESDAY AS IT IS FORECAST BY GLOBAL MODELS TO DROP IN FROM THE
NORTHWEST. HOWEVER...THE EC SOLUTION STILL DEPICTS A SLOWER...DEEPER
AND MORE MOIST SYSTEM THAN THE GFS. WILL HAVE TO SEE HOW THIS PANS
OUT...BUT IT CURRENTLY DOES NOT APPEAR TO BE AS COLD OF A SYSTEM AS
MODELS WERE INDICATING LAST NIGHT.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL AT THE KSLC TERMINAL
TODAY...WITH A 20 PERCENT CHANCE OF CEILINGS DROPPING TO 6000 FT
DURING BRIEF VICINITY SHOWERS THIS AFTERNOON. SOUTHERLY WINDS WILL
DOMINATE THROUGHOUT THE DAY...BECOMING GUSTY AFTER ABOUT 16Z.

&&

.FIRE WEATHER...STORM TIMING IS RIGHT ON TRACK WITH GUSTY
SOUTHWESTERLY WINDS TODAY AHEAD OF A STATEWIDE SOAKING TOMORROW.
PRECIPITATION WILL BEGIN IN THE WESTERN PORTION OF THE STATE THIS
AFTERNOON AND WILL RAPIDLY SPREAD EAST. WETTING RAINS WILL ENSCONCE
THE ENTIRE REGION BY TOMORROW AFTERNOON. SUNDAY WILL BRING DRYING
FROM THE SOUTHWEST...LEAVING THE REMAINING CHANCES OF WETTING RAIN
TO THE NORTHERN THIRD OF THE STATE THROUGH SUNDAY EVENING. SNOW
LEVELS ARE STILL EXPECTED TO LOWER TO NEAR 9000 FT WITH STORM TOTALS
RANGING FROM ONE TO TWO INCHES OF SNOW IN THE SOUTHERN AND CENTRAL
MOUNTAINS TO A POSSIBLE FIVE INCHES AT THE HIGHEST PEAKS OF THE
WASATCH AND UINTA MOUNTAINS. LINGERING PRECIP IS EXPECTED IN THE
NORTHERN MOUNTAINS ON MONDAY AND POSSIBLY INTO MIDWEEK.

&&

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

$$

CHENG/VERZELLA

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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