Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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000
FXUS65 KSLC 282150
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
350 PM MDT TUE JUL 28 2015

.SYNOPSIS...A COOL AIRMASS WILL REMAIN IN PLACE THROUGH TONIGHT.
A WARMING TREND IS EXPECTED FOR THE LATTER HALF OF THE WEEK AS
STRONG HIGH PRESSURE BUILDS OVER THE GREAT BASIN. MOISTURE WILL
BEGIN TO RETURN TO SOUTHERN UTAH LATE THIS WEEK AND THEN SPREAD
SLOWLY NORTH OVER THE WEEKEND.

&&

.SHORT TERM (THROUGH 12Z FRIDAY)...HEIGHTS WILL CONTINUE TO BUILD
THROUGH THE SHORT TERM PERIOD AS HIGH PRESSURE CURRENTLY CENTERED
OVER THE SOUTHERN PLAINS EXPANDS NORTH AND WEST THROUGH THE EASTERN
GREAT BASIN. THE AXIS OF THIS HIGH IS EXPECTED TO STRETCH WEST
ACROSS THE UT/AZ BORDER THROUGH THURSDAY...ESSENTIALLY PINNING THE
RETURN FLOW MOISTURE SOUTH OF THE AREA THROUGH THAT TIME. DUE TO
THIS DRY AND STABLE CONDITIONS WILL LARGELY DOMINATE THROUGH THE
PERIOD. THIS SAID...A SLIGHT NORTHERLY SHIFT OF THIS AXIS WILL ALLOW
SOME MID LEVEL MOISTURE ADVECTION TO SEEP INTO THE UT/AZ BORDER
REGION THURSDAY...POTENTIALLY ALLOWING FOR ISOLATED HIGH BASED
CONVECTION THURSDAY AFTERNOON ACROSS THE SOUTHERN MOUNTAINS. HAVE
MAINTAINED SLIGHT CHANCE POPS AS SUCH...BUT EXPECT PRIMARILY TERRAIN
BASED CU AND MINIMAL PRECIP THREATS WILL BE THE OUTCOME.

H7 TEMPS WILL CONTINUE TO CLIMB COINCIDENT WITH BUILDING HEIGHTS
ALLOWING A MARKED WARMING TREND THROUGH LATE WEEK. SAID TEMPS ARE
ANTICIPATED TO CLIMB FROM VALUES NEAR +4C /12Z THIS MORNING/ TO +14
C BY 00Z FRIDAY ALLOWING MAX TEMPS TO APPROACH MORE NORMAL LEVELS BY
THURSDAY AFTERNOON.

.LONG TERM (AFTER 12Z FRI)...MEDIUM RANGE MODELS REMAIN IN GOOD
AGREEMENT ON THE EVOLUTION OF THE LARGE SCALE PATTERN FOR THE
LATTER HALF OF THE WEEK THROUGH THE WEEKEND. THE AXIS OF THE LARGE
E-W ORIENTED UPPER RIDGE SHIFTS OVER NORTHERN UT BY FRI MORNING
ALLOWING THE MOISTURE IN PLACE TO THE SOUTH OF IT TO SPREAD NORTH
INTO THE SRN HALF OF THE CWA WITH AN INCREASE IN CONVECTION ACROSS
THE SOUTH FRI AFTN.

THE RIDGE BECOMES MORE CIRCULAR OVER THE WEEKEND BUT THE CENTER
REMAINS TOO CLOSE TO UT TO ALLOW DEEP SLY FLOW TO DEVELOP. THIS
PREVENTS A STRONG MOISTURE SURGE BUT THE HIGH DOES GRADUALLY FILL
WITH MOISTURE OVER THE WEEKEND WITH AN INCREASE OF TERRAIN BASED
CONVECTION EACH DAY. THE LIGHT FLOW REGIME UNDER THE HIGH WILL
KEEP CELLS FROM DRIFTING VERY FAR FROM WHERE THEY FORM. EXPECT A
SUFFICIENTLY MOIST AIRMASS TO BE IN PLACE BY MON TO WARRANT LOW
POPS AREA WIDE EVEN WITH THE LIGHT FLOW.

WITH THE RIDGE AXIS SHIFTING OVERHEAD FRI MOST VALLEY TEMPERATURES
WILL CONTINUE TO CLIMB AND WILL REMAIN VERY WARM THROUGH THE
WEEKEND. THE AREAS MORE PRONE TO CONVECTION SHOULD LEVEL OFF SAT
AND MAY EVEN COOL A BIT SUN. EXPECT A SLIGHT COOLING TREND FOR THE
FIRST PART OF NEXT WEEK DUE TO THE MOISTURE INCREASE.

&&

.AVIATION...NORTHWEST WINDS WILL REMAIN IN PLACE THROUGH THIS
EVENING...WITH A RETURN TO LIGHT SOUTHEAST WINDS AFTER 05-06Z.

&&

.FIRE WEATHER...THE COOL AND STABLE AIRMASS IN PLACE WILL
GRADUALLY WARM TOMORROW...WITH A MORE SIGNIFICANT WARMING TREND
EXPECTED FOR THE LATTER HALF OF THE WEEK THROUGH NEXT WEEKEND.
HIGH PRESSURE BUILDING NORTHWEST THROUGH THE DISTRICT AT THIS TIME
WILL MAINTAIN LARGELY DRY CONDITIONS THROUGH THURSDAY...BUT
MOISTURE PINNED SOUTH OF THE DISTRICT WILL BEGIN TO SHIFT NORTH
ACROSS THE AREA THURSDAY THROUGH THE WEEKEND AS THE HIGH PRESSURE
SHIFTS EAST ALLOWING A MORE PRONOUNCED SOUTHERLY FLOW ALOFT TO
DEVELOP. DO NOT FORESEE ANY CRITICAL FIRE WEATHER CONDITIONS DUE
TO WIND OR LOW RH...BUT ISOLATED DRY LIGHTNING MAY BECOME A THREAT
AS THE MOISTURE BEGINS TO SPREAD IN FROM THE SOUTH.

&&

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

$$

MERRILL/WILENSKY

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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