000
FXUS65 KSLC 151021
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
421 AM MDT WED MAY 15 2013

.SYNOPSIS...A WEAK UPPER LEVEL DISTURBANCE WILL MOVE EAST ACROSS
SOUTHERN UTAH TODAY. BEHIND THIS SYSTEM A STRONGER TROUGH WILL
MOVE INTO THE GREAT BASIN LATE IN THE WEEK...FOLLOWED BY A STILL
COLDER SYSTEM OVER THE WEEKEND.

&&

.DISCUSSION...A COMPACT CIRCULATION CENTER OVER SOUTHERN NEVADA
EARLY THIS MORNING WILL TRACK EAST ACROSS SOUTHERN UTAH TODAY.
THIS FEATURE WILL LOSE SOME OF ITS DEFINITION AS IT MOVES THROUGH
UTAH...BUT STILL SHOULD BE ABLE TO GENERATE ENOUGH DYNAMIC TO FORM
CONVECTION IMMEDIATELY NORTH AND EAST OF THE CENTER LATER THIS
MORNING THROUGH THIS AFTERNOON.

A PERIOD OF COOL AND UNSETTLED WEATHER IS SHAPING UP FOR
FRIDAY THROUGH AT LEAST EARLY MONDAY. THE LEADING TROUGH WILL
REACH THE WEST COAST THURSDAY NIGHT...THEN LIFT EAST-NORTHEAST AS
A SOMEWHAT DIFFLUENT TROUGH ACROSS THE GREAT BASIN FRIDAY. A WELL-
DEFINED SURFACE FRONT WILL SET UP ACROSS EASTERN NEVADA THROUGH
EXTREME NORTHWEST UTAH BY LATE THURSDAY AFTERNOON OR EVENING. THIS
FRONT WILL GENERATE BREEZY AND WARM CONDITIONS THURSDAY WITH
LITTLE THREAT FOR CONVECTION DURING THE DAY. THE EASTWARD PUSH OF
THE FRONTAL BOUNDARY WILL LACK STRONG LOW-LEVEL COLD ADVECTION...
BUT WILL HAVE ENOUGH MID-LEVEL COOLING TO SUPPORT SCATTERED
CONVECTION BEHIND THE FRONT ACROSS NORTHWEST UTAH FRIDAY.

THE NEXT SYSTEM ON THE HEELS OF THE FRIDAY TROUGH WILL BRING MORE
COLD AIR AND A RENEWED THREAT FOR PRECIP TO MAINLY NORTHERN UTAH
LATE IN THE WEEKEND. THE 00Z ECMWF OFFERS UP A MUCH BETTER THREAT
FOR WIDESPREAD PRECIP AS IT BRING DEEP LAYER COLD ADVECTION AND
MOISTURE ALONG WITH DYNAMIC LIFT SUPPLIED BY THE MID-LEVEL TROUGH.
THE GFS LACKS THE DEEP LAYER MOISTURE AND INSTABILITY AS THE MID-
LEVEL COLD POOL REMAINS FURTHER TO THE NORTH OVER THE NORTHERN
ROCKIES. AT THIS POINT COOLER TEMPS LOOKS TO BE A GIVEN...
ESPECIALLY UP NORTH WHERE READINGS WILL LIKELY DROP BELOW NORMAL
FOR EARLY IN THE WEEK. WILL PUT THE GREATEST THREAT FOR PRECIP UP
NORTH WITH A BIAS TOWARDS THE LATEST ECMWF SOLUTION.

WILL BRING SUBSTANTIALLY WARMER/DRIER/BREEZY CONDITIONS BACK INTO
THE REGION MIDWEEK AS THE UPPER RIDGE RETURNS TO THE INTERIOR
WEST. WARM AND GENERALLY DRY CONDITIONS WILL LIKELY PERSIST
THROUGH THE END OF THE WEEK.

&&

.AVIATION...WINDS AT THE KSLC TERMINAL WILL REMAIN GENERALLY
SOUTHERLY EARLY THIS MORNING THEN SWITCH TO NORTHWEST BETWEEN
13-15Z THIS MORNING AS A WEAK FRONT FINALLY REACHES THE AIRFIELD.
VFR CONDITIONS WILL PREVAIL WITH ANY CEILINGS WELL ABOVE 7000 FT.

&&

.FIRE WEATHER...A WEAK COLD FRONT WILL CROSS MAINLY NORTHERN
UTAH TODAY...BUT EVEN BEHIND THE COLD FRONT...WELL ABOVE NORMAL
TEMPERATURES WILL CONTINUE ACROSS MUCH OF THE REGION. ANOTHER DAY
OF ABOVE NORMAL TEMPERATURES IS EXPECTED THURSDAY AHEAD OF A
STRONGER COLD FRONT THAT IS EXPECTED TO SLOWLY CROSS THE AREA
LATE IN THE WEEK.

STRONGER WINDS AND LOW HUMIDITIES ARE EXPECTED AHEAD OF THIS COLD
FRONT THURSDAY AFTERNOON AND EVENING...ESPECIALLY ACROSS PORTIONS
OF SOUTHERN UTAH. DEPENDING ON FUEL STATUS...CRITICAL CONDITIONS
ARE POSSIBLE THURSDAY AFTERNOON AND EVENING ACROSS SOUTHWESTERN
UTAH. ANOTHER ROUND OF GUSTY WINDS AND LOW HUMIDITIES CAN BE
EXPECTED ON FRIDAY ACROSS SOUTHEASTERN UTAH.

&&

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

$$

PUBLIC...CONGER
FIRE WEATHER/AVIATION...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)