Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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000
FXUS65 KSLC 222138
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
338 PM MDT FRI APR 22 2016

.SYNOPSIS...A STORM SYSTEM WILL IMPACT THE AREA LATE TONIGHT
THROUGH SATURDAY WITH A COLD FRONT PASSAGE...BRINGING SHOWERS AND
MUCH COOLER TEMPERATURES. A SECOND STORM SYSTEM WILL REACH THE
AREA EARLY NEXT WEEK...FOLLOWED BY ANOTHER LATER IN THE WEEK.

&&

.SHORT TERM...SATELLITE IMAGERY THIS AFTERNOON SHOWS A LARGE
CIRCULATION CENTER MOVING THROUGH NORTHERN CALIFORNIA ASSOCIATED
WITH AN UPPER LEVEL LOW PRESSURE SYSTEM. A FEW LIGHTNING STRIKES
HAVE BEEN OBSERVED ACROSS NORTHERN CALIFORNIA AND WESTERN NEVADA
AS THE SYSTEM MOVES THROUGH. MEANWHILE...NUMEROUS HIGH-LEVEL
CLOUDS ARE STREAMING THROUGH OUR AREA IN ADVANCE OF THIS LOW. AT
THE SURFACE...GUSTY SOUTH WINDS HAVE DEVELOPED ACROSS THE EASTERN
GREAT BASIN. STRONG 700MB WINDS HAVE MIXED DOWN TO THE
SURFACE...IN ADDITION TO A TIGHTENING SURFACE GRADIENT. THUS
FAR...THE STRONGEST GUST OBSERVED ACROSS OUR FORECAST AREA WAS A
REMOTE SITE WEST OF MILFORD WHICH RECORDED A 61 MPH GUST EARLIER
TODAY. IN GENERAL...EXPECTING 40-50 MPH GUSTS TO CONTINUE INTO THE
EVENING ALONG WITH BLOWING DUST. THE BIGGEST IMPACT WILL LIKELY BE
CROSS WINDS ALONG EAST-WEST ORIENTED ROADS...WITH A FEW LOCATIONS
SEE LIMITED VISIBILITIES IN BLOWING DUST.

AS THE LOW PROGRESSES ACROSS NEVADA LATE TODAY...THE SURFACE
TEMPERATURE GRADIENT WILL TIGHTEN AND CREATE A TYPICAL SPRING
GREAT BASIN COLD FRONT. CURRENT PROJECTIONS MOVE THE FRONT INTO
UTAH AROUND 3AM...REACHING THE WASATCH FRONT AROUND 6AM...THEN
PUSHING THROUGH THE MAJORITY OF UTAH AND SOUTHWEST WYOMING BY
AROUND NOON. A BURST OF STRONG WEST TO NORTHWEST WINDS WILL
ACCOMPANY THE FRONT...THOUGH WINDS ARE GENERALLY EXPECTED TO NOT BE
AS STRONG AS OBSERVED THIS AFTERNOON. THE EXCEPTION IS NORTHEAST
UTAH WHERE THE WIND ADVISORY WILL NEED TO BE EXTENDED INTO
TONIGHT. MEANWHILE...CONVECTIVE PARAMETERS INDICATE A MODESTLY-
FAVORABLE ENVIRONMENT FOR THUNDERSTORMS WITH THE FRONT PASSAGE
FROM AROUND UTAH COUNTY NORTHWARD. 700MB TEMPS DROP TO AROUND THE
-5C RANGE...SUGGESTING SNOW LEVELS POSSIBLY TO WASATCH FRONT
BENCHES. WHILE WE CANNOT RULE OUT SOME FLAKES TO VALLEY FLOORS AS
WELL...ACCUMULATING SNOW IS VERY UNLIKELY. SEVERAL INCHES OF SNOW
CAN BE EXPECTED IN THE MOUNTAINS...GENERALLY ABOUT 6500 FEET
ELEVATION. WE`RE LOOKING AT GENERALLY 4-8 INCHES IN THE NORTHERN
UTAH MOUNTAINS AND A FEW INCHES IN THE CENTRAL MOUNTAINS. THE
SOUTHERNMOST PARTS OF UTAH INCLUDING ZION NP AND ST GEORGE WILL
LIKELY ESCAPE UNSCATHED...WITH SOME BREEZES...CLOUDS...AND COOLER
TEMPERATURES BEING THE ONLY EFFECT OF THE LOW BRUSHING TO THE
NORTH.

LINGERING SCATTERED SHOWERS CAN BE EXPECTED SATURDAY AFTER THE
FRONT PASSES...ESPECIALLY FOR NORTHERN UTAH. ANOTHER IMPULSE IS
PROJECTED TO ROTATE THROUGH IN THE AFTERNOON...BRINGING ANOTHER
PERIOD OF INCREASED SHOWER ACTIVITY. OVERALL...A MUCH COOLER AND
DAMP DAY IS IN STORE FOR MOST OF THE FORECAST AREA. SHOWERS MAY
LINGER INTO THE NIGHT AS THE LOW PULLS EAST OF THE
AREA...ESPECIALLY OVER THE BEAR RIVER RANGE AND UINTAS.

A SHORT-WAVE RIDGE MOVING IN SUNDAY WILL BRING DRYING TO THE
AREA AND MODESTLY WARMER TEMPERATURES...RIGHT AROUND SEASONAL
NORMALS. THE BREAK WILL SHORT-LIVED HOWEVER AS THE NEXT IN A
PARADE OF STORMS APPROACHES THE FORECAST AREA BY SUNDAY EVENING.

.LONG TERM (AFTER 00Z MONDAY)...THE NEXT UPPER LEVEL LOW SYSTEM IN
A SERIES OF SYSTEMS DEVELOPS OFF THE COAST OF OREGON/WASHINGTON
STATE MONDAY AND DROPS SOUTHWARD ALONG THE CALIFORNIA COAST BEFORE
MAKING A DUE EAST TURN. SUBTLE WARM ADVECTION AHEAD OF THE NEXT
FRONT...WHICH LOOKS TO MOVE THROUGH WEST -SOUTHWEST UTAH MONDAY
MORNING...WILL SEE ANOTHER WINDY MORNING WITH THE FRONTAL PASSAGE.
UNSETTLED WEATHER LASTING THROUGH MID WEEK FOR MOST OF THE STATE
WILL KEEP TEMPERATURES CLOSER TO SEASONAL NORMAL AS COMPARED TO
THE PREVIOUS WEEK.

SUBTLE RIDGING BEHIND THE DEPARTING SHORTWAVE ON WEDNESDAY WILL BE
SHORT LIVED AS FORECAST MODELS ADVERTISE YET ANOTHER UPPER LEVEL
CIRCULATION DROPPING SOUTHWARD ALONG THE CALIFORNIA
COAST. DIFFERENCES BETWEEN MODELS ARISE BETWEEN THE LOCATION AND
TREK OF THIS SHORT WAVE. WHILE THE GFS ADVERTISES A MORE EAST
-NORTHEAST TREK TAKING THE LOW THROUGH SOUTHERN NEVADA AND ACROSS
SOUTHERN UTAH/NORTHERN ARIZONA...THE LATEST ECMWF DROPS THE LOW
FARTHER SOUTH STRADDLING THE ARIZONA/MEXICO BORDER LATE THURSDAY
INTO FRIDAY. CONFIDENCE IS LOW AT THIS TIME FOR THE FAR EXTENDED
AS TO WHETHER OR NOT WHICH MODEL TO TOTALLY LEAN ON...SO A BLEND
OF MODELS APPROACH WAS TAKEN.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL AT KSLC FOR THE REMAINDER
OF THE EVENING WITH SOME PASSING HIGH CLOUDS. SOUTHERLY WINDS
WILL CONTINUE THROUGH THE EVENING AND WILL REMAIN GUSTY INTO THE
OVERNIGHT HOURS. FRONTAL PASSAGE IS EXPECTED AROUND 12Z
SATURDAY...WHEN MVFR CONDITIONS ARE EXPECTED TO SETTLE IN WITH
RAIN AND LOW CIGS. AT FRONTAL PASSAGE TIME...MAY SEE TSRA FOR
BRIEF PERIOD.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...WIND ADVISORY UNTIL 10 PM MDT THIS EVENING FOR UTZ003-015-016.

     WIND ADVISORY UNTIL 6 AM MDT SATURDAY FOR UTZ005.

WY...NONE.
&&

$$

PUBLIC...VAN CLEAVE
AVIATION...DEWEY

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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