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000
FXUS65 KSLC 131552
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
952 AM MDT MON MAY 13 2013

.SYNOPSIS...A VERY WARM AIRMASS WILL BE OVER THE AREA TODAY. A
PACIFIC TROUGH WILL PASS THROUGH THE NORTHERN ROCKIES OVER THE
NEXT 48 HOURS BRINGING SOME SLIGHT COOLING TO NORTHERN UTAH
TUESDAY. SOUTHWEST FLOW RETURNS TO THE AREA LATE WED THROUGH
THURSDAY.

&&

.DISCUSSION...UPPER TROUGH OFF THE WEST COAST WILL PUSH INLAND AND
FLATTEN THE RIDGE OVER THE GREAT BASIN TUESDAY. SURFACE COLD FRONT
ASSOCIATED WITH AFOREMENTIONED TROUGH IS DIFFICULT TO FIND THIS
MORNING BUT APPEARS TO BE SOMEWHERE IN EASTERN OREGON. ANOTHER
WEAK UPPER TROUGH AT 35N/130W THIS MORNING LOOKS TO COMPLICATE THE
PICTURE OVER THE NEXT 48 HOURS.

MODELS ARE TRENDING TOWARDS A WEAKER FROPA THIS EVENING...WITH
LATEST 12Z NAM SUGGESTING WE MIGHT NOT EVEN SEE A WIND SHIFT UNTIL
TUESDAY MORNING. SOUTHWEST FLOW IS NOT TERRIBLY STRONG AND GIVEN
LAKE TEMP BELIEVE WE WILL STILL SEE A LATE LAKE BREEZE...BUT WHERE
PREVIOUSLY THE THINKING WAS THE FRONT WOULD HAVE REINFORCED THE
LOW LEVEL NORTHERLY FLOW...THIS NOT LOOKING SO CERTAIN
ANYMORE.

BOTTOM LINE IS THERE IS NOT GOING TO BE A LOT OF COOLING WITH THIS
FRONT. WILL WAIT FOR 12Z GLOBAL RUNS...BUT WOULD NOT BE SURPRISED
IF TUE/WED FORECAST TEMPS NEED TO BE INCREASED A FEW DEGREES.

OTHERWISE NOT MUCH ACTION WITH THIS PATTERN...COULD BE SOME HIGH
BASED MICROBURST TYPE CONVECTION NEAR THE FRONTAL ZONE AS IT
STALLS AND DIES ACROSS UT TUES/WED.

THU NIGHT/FRI SYSTEM LOOKS A BIT MORE VIGOROUS THAN TONIGHT/TUES SYSTEM
WITH STRONGER SOUTHERLY WINDS AHEAD OF FRONT AND MORE COOLING
ALOFT AND AT THE SURFACE WITH TROUGH/FRONT FRIDAY.

NO CHANGES TO CURRENT FORECAST AT THIS TIME...STILL LOOKING FOR
NEAR OR RECORD MAX TEMPS TODAY.

&&

.AVIATION...SOUTH WINDS WILL REMAIN IN PLACE AT THE KSLC TERMINAL
THROUGH AT LEAST MID AFTERNOON. THERE IS A 40 PERCENT CHANCE THAT
WINDS WILL BECOME LIGHTER AND SOUTHWEST OR NORTHWEST LATE THIS
AFTERNOON WITH THE LAKE BREEZE DISRUPTING THE SOUTH WINDS. NORTHWEST
WINDS ARE FORECAST WITH THE PASSAGE OF A COLD FRONT LATE THIS
EVENING OR EARLY OVERNIGHT. VFR CONDITIONS ARE EXPECTED TO BE
MAINTAINED THROUGH THE VALID TAF PERIOD.

&&

.FIRE WEATHER...ACTIVE LATE SPRING PATTERN IN PLACE. AFTERNOON
VALLEY HUMIDITY VALUES WILL BE IN THE 10-15% RANGE THROUGH THE WORK
WEEK BEFORE RISING A BIT DURING THE WEEKEND. POOR OVERNIGHT MOISTURE
RECOVERY IS EXPECTED THROUGH THE WORK WEEK.

SOUTHERLY WINDS WILL INCREASE ACROSS THE WEST DESERT LATE THIS
AFTERNOON AND EVENING AHEAD OF AN APPROACHING COLD FRONT. LOCALLY
CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE THOUGH FUELS ARE
DEEMED NOT CRITICAL AT THIS TIME. TODAY WILL BE VERY WARM WITH
ISOLATED CONVECTION IN THE HIGHER TERRAIN.

A SLIGHT COOL DOWN AND SLIGHT INCREASE IN MOISTURE IS FORECAST
TUESDAY ACROSS NORTHERN AND CENTRAL UTAH WITH THE PASSAGE OF THE
COLD FRONT. WESTERLY WINDS IN DOWNSLOPE LOCATIONS MAY NEAR CRITICAL
FIRE WEATHER CRITERIA WITH MARGINAL HUMIDITY. FURTHER SOUTH ACROSS
SOUTH CENTRAL UTAH...IT WILL REMAIN VERY WARM AND DRY WITH MARGINAL
WESTERLY WINDS. HOWEVER FUELS ARE DEEMED NOT CRITICAL AT THIS TIME.
ISOLATED CONVECTION AGAIN EXPECTED IN THE TERRAIN.

A WEAK DISTURBANCE APPROACHES SOUTHERN UTAH WEDNESDAY. THIS MAY
ALLOW GUSTY SOUTHWEST WINDS ACROSS SOUTHERN UTAH TO DEVELOP AS
HUMIDITY VALUES DIP A BIT. LOCALLY CRITICAL FIRE WEATHER CONDITIONS
ARE POSSIBLE ACROSS SOUTHERN UTAH WITH ISOLATED CONVECTION AGAIN IN
THE HIGHER TERRAIN.

THERE IS THE POTENTIAL FOR A STRONGER COLD FRONT THURSDAY INTO
FRIDAY WHICH COULD PROVIDE EVEN GUSTIER SOUTH WINDS AND VERY LOWER HUMIDITY
LEVELS AHEAD OF THIS FEATURE. IT LOOKS LIKE STRONG WARNING
POTENTIAL FROM A METEOROLOGICAL STANDPOINT WHERE FUELS ARE DEEMED
CRITICAL. CONVECTION WILL INCREASE IN COVERAGE DURING THIS PERIOD.

IN THE EXTENDED...EXPECT A COOLER AND WETTER PATTERN TO EMERGE NEXT
WEEKEND WITH THE ARRIVAL OF A TROUGH.

&&

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

$$

PUBLIC...DUNN
FIRE WEATHER/AVIATION...ROGOWSKI

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)