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AREA FORECAST DISCUSSION

 
 FXUS65 KSLC 032206
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
306 PM MST TUE MAR 3 2015

.SYNOPSIS...A COLD UPPER TROUGH WILL CROSS THE REGION THROUGH THE
EVENING HOURS. A COOL NORTHERLY FLOW WILL BE OVER THE AREA
WEDNESDAY. HIGH PRESSURE WILL BRING A DRYING AND WARMING TREND
THROUGH THE REST OF THE WEEK.

&&

.SHORT TERM (THROUGH 00Z SATURDAY)...
WATER VAPOR LOOP SHOWS THE TROUGH AXIS APPROACHING WITH AN
EMBEDDED WAVE NEARING THE NORTHWEST CORNER OF UTAH. AMDAR
400-250MB WIND OBSERVATIONS CONFIRM THE POSITION OF THE UPPER
LEVEL JET AXIS TO OUR NORTHWEST...ALONG WITH A 125-175KT
SOUTWHESTERLY JET FROM THE FOUR CORNERS THROUGH THE GREAT LAKES.
GOES/GPS/RAP/12Z RAOB INDICATE THE PRECIPITABLE WATER VALUE RANGES
BETWEEN 0.10-0.15" MOUNTAINS...TO 0.30-0.35" MOST VALLEYS. BLENDED
TOTAL PRECIPITABLE WATER PRODUCT INDICATES AN ABNORMALLY DRY
AIRMASS ACROSS THE WEST WITH THE EXCEPTION OF THE GREAT BASIN.

COLD FRONT WILL CLEAR SOUTHERN UTAH BY LATE EVENING. INSTABILITY
SHOWERS ACROSS THE SOUTH WILL LIKELY BECOME A BIT MORE NUMEROUS FROM
FILLMORE TO CEDAR CITY WITH FAVORABLE NORTHERLY UPSLOPE DEVELOPING.
COULD SEE LOCAL ACCUMULATIONS OF UP TO 2 INCHES IN THESE PARTS. THIS
IS THE PORTION OF THE STATE THAT WE FOCUSED OUR POPS/QPF ON THROUGH
THE EVENING HOURS...WITH THE REST OF THE STATE SEEING A DOWNWARD
TREND IN ISOLATED TO SCATTERED SHOWERS. STILL SEE AN ISOLATED CHANCE
FOR THUNDER ACROSS SOUTHERN UTAH THROUGH SUNSET PER SREF/RAP BUFKIT
AND OBSERVED STRIKES THIS AFTERNOON.

WHILE INSTABILITY DUE TO THE WARM LAKE SURFACE WILL BE FAVORABLE FOR
LAKE EFFECT SHOWERS INTO THE EVENING...THIS CHANGES QUICKLY
OVERNIGHT WITH ADJUSTED RAP SOUNDINGS INDICATING LOWERING EQUILIBRIUM
LEVELS AND THINNING LAKE INDUCED CAPE THIS EVENING AS SUBTLE WARMING
BEGINS. BY MIDNIGHT THERE IS NO LAKE INDUCED CAPE TO SPEAK OF.

PRESSURE GRADIENT ACROSS SOUTHERN UTAH INCREASES BEHIND THE COLD
FRONT TONIGHT. 700MB COLD ADVECTION AND 25KT WINDS SHOULD SUPPORT 30-
45 MPH GUSTS IN FAVORABLE DOWNSLOPE/CANYON AREAS. THESE WINDS SHOULD
GRADUALLY SLACKEN TOMORROW AFTERNOON AND EVENING.

KEPT MENTION OF ISOLATED SNOW SHOWERS FOR THE NORTHEAST MOUNTAINS
LATE TONIGHT WITH PASSAGE OF A WEAK TRAILING WAVE.

OTHERWISE BUILDING HIGH PRESSURE SURFACE AND ALOFT SHOULD SUPPLY
BENIGN WEATHER WITH A WARMING TREND THROUGH THE REMAINDER OF THE
WEEK.

&&

.LONG TERM (AFTER 00Z SATURDAY)...
VERY LITTLE WEATHER OF NOTE IN THE EXTENDED FORECAST...AS HIGH
PRESSURE DOMINATES THE SOUTHWESTERN CONUS FOR MUCH OF THE FORECAST
PERIOD. A FEW VERY WEAK SHORTWAVES COULD SLIDE OVER THE AREA IN
THE NORTHWEST FLOW ALOFT THROUGH THE WEEKEND AND EARLY PART OF THE
WORK WEEK...BUT LITTLE IMPACT IS EXPECTED...WITH TEMPERATURES
REMAINING ABOVE CLIMATOLOGICAL NORMALS AND CLOUD COVER STAYING
MOSTLY CONFINED TO CIRRUS LEVEL.

THE RIDGE LOOKS TO FLATTEN THROUGH THE DAY TUESDAY...WHICH COULD
OPEN UP THE REGION TO A BROAD TROUGH MOVING IN FROM THE PACIFIC.
HOWEVER...IT CURRENTLY LOOKS LIKE THE EARLIEST THIS TROUGH WOULD
IMPACT THE FORECAST AREA IS WEDNESDAY...WHICH IS CURRENTLY DAY 8 FOR
THE FORECAST. HAVE INTRODUCED SOME 10 PERCENT POPS ACROSS WESTERN
UTAH FOR THE LATTER HALF OF TUESDAY...BUT OTHERWISE THERE ARE NO
TRULY CONSISTENT DETAILS TO LATCH ONTO YET FOR THE LATTER HALF OF
NEXT WEEK.

&&

.AVIATION...THERE IS A 20 PERCENT CHANCE OF MVFR OR IFR SNOW SHOWERS
AT THE SLC TERMINAL BETWEEN 22Z AND 01Z. CEILINGS SHOULD GENERALLY
IMPROVE THROUGH THE EVENING...LIKELY LIFTING ABOVE 7000FT BETWEEN
23Z AND 02Z. AFTER THIS...LOWER CEILINGS ARE EXPECTED TO STAY OVER
THE MOUNTAINS THROUGH THE EVENING AND OVERNIGHT HOURS.
HOWEVER...THERE IS A SLIGHT CHANCE THAT THESE LOWER CEILINGS LINGER
THROUGH THE EVENING AND PAST 06Z IF THEY BUILD BACK INTO THE VALLEY
AREAS. WINDS SHOULD STAY NORTHERLY UNTIL 05Z-08Z...WHEN LIGHT
SOUTHERLY OR LIGHT AND VARIABLE WINDS WILL LIKELY DEVELOP.

&&

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




SHORT TERM...ROGOWSKI
LONG TERM/AVIATION...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)