Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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FXUS65 KSLC 011023
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
423 AM MDT FRI AUG 1 2014

.SYNOPSIS...HIGH PRESSURE ALOFT WILL STRENGTHEN ACROSS THE
INTERIOR WEST OVER THE FIRST HALF OF THE UPCOMING WEEKEND. A
STRONGER AND SIGNIFICANTLY MORE MOIST WEATHER DISTURBANCE WILL
LIFT NORTH THROUGH THE GREAT BASIN AND IMPACT MUCH OF UTAH SUNDAY
THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM (UNTIL 06Z TUESDAY)...AN APPARENT SHORTWAVE RIDING
EAST ALONG A WEAK NEAR 700MB THERMAL BOUNDARY OVER SOUTHERN UTAH
BROUGHT ORGANIZED CONVECTION TO THE SOUTHERN TIER OF UTAH
OVERNIGHT. THE REMNANT OF THE ACTIVITY HAS MOVED INTO SOUTHEAST
UTAH WITH A WEAKENING TREND THE PAST COUPLE OF HOURS. A FEW
ADDITIONAL TRIALING SHOWERS ACROSS SOUTHWEST UTAH ARE ALSO
WEAKENING AND SHOULD BE ALL BUT GONE BY AROUND SUNRISE.

GOES TPW IMAGERY CONTINUES TO SHOW A FAIRLY LARGE AREA OF 1.00+
PWAT VALUES ACROSS SOUTHERN/WESTERN UTAH...WITH STILL RESPECTABLE
.75 - .90 INCH VALUES ACROSS THE REMAINDER OF THE FORECAST AREA.
WEAK FLOW ALOFT SHOULD KEEP MUCH OF THIS MOISTURE IN PLACE...
LEADING TO SOME CONVECTION AGAIN THIS AFTERNOON/EVENING. PINNING
DOWN WHERE THIS ACTIVITY IS MOST LIKELY TO DEVELOP IS DIFFICULT
AS THE DYNAMIC LIFT IS WEAK AT BEST. THE VARIOUS MODEL GUIDANCE
STABILITY PARAMETERS SEEM TO SUGGEST THE BEST THREAT WILL REMAIN
ACROSS THE CENTRAL AND SOUTHERN PORTIONS OF THE STATE. FOR NOW
WILL MAINTAIN MORE TERRAIN-BASED POPS AS THE FLOW IS QUITE WEAK.

HIGH PRESSURE ALOFT WILL STRENGTHEN ACROSS THE GREAT BASIN THE
NEXT COUPLE OF DAYS. TRAPPED MOISTURE WILL LIKELY EVOLVE INTO A
SUBSTANTIAL AMOUNT OF TERRAIN-BASED CUMULUS...THOUGH DEEP
CONVECTION AND PRECIP MAY BE SOMEWHAT LIMITED THROUGH SATURDAY.
TEMPERATURES WILL ALSO WARM UP...WITH MOST READINGS GETTING BACK
TO AROUND SEASONAL NORMS.

A SUBSTANTIAL MONSOONAL SURGE IS STILL ADVERTISED IN THE MODEL
GUIDANCE BEGINNING LATE IN THE UPCOMING WEEKEND. THE VARIOUS MODEL
GUIDANCE HAVE REMAINED FAIRLY CONSISTENT IN BRINGING AN EASTERLY
WAVE ACROSS NORTHERN MEXICO/SOUTHERN ARIZONA...THEH TURNING IT
NORTHWARD THROUGH EASTERN NEVADA/WESTERN UTAH BY LATE
SUNDAY/MONDAY. DEEP LAYER MOISTURE TAPPED BY THIS FEATURE WILL
FUEL WHAT COULD BE A SIGNIFICANT PRECIP EVENT EARLY IN THE
UPCOMING WEEK. CONFIDENCE FAIRLY HIGH AT THIS TIME DUE TO THE RUN-
TO-RUN CONSISTENCY OF BRINGING THIS FEATURE NORTH THROUGH THE
AREA. HAVE BOOSTED POPS CONSIDERABLY FOR LATE SUNDAY THROUGH
MONDAY EVENING...WITH SOME MENTION OF HEAVY RAINFALL IN THE
FORECAST.

&&

.LONG TERM (AFTER 06Z TUESDAY)...A SIGNIFICANT MONSOONAL SURGE WILL
BE ONGOING AT THE BEGINNING OF THE LONG TERM FORECAST PERIOD. A
DISTURBANCE MOVING ACROSS THE GREAT BASIN WILL HELP TO KEEP
CONVECTION GOING INTO THE NIGHTTIME HOURS MONDAY. THE EC INDICATES A
PERIOD OF SUBSIDENCE CAN BE EXPECTED BEHIND THIS WAVE TUESDAY
AFTERNOON ACROSS ALL BUT NORTHERN UTAH WHILE THE GFS IS DECIDEDLY
MOISTER AND MORE UNSTABLE OVER A LARGER AREA OF THE CWA. LEANED
TOWARD THE GFS SOLUTION FOR TUESDAY AFTERNOON.

THE GFS CONTINUES TO BRING A SERIES OF DISTURBANCES THROUGH THE AREA
THROUGH THE END OF THE WEEK...WITH REMNANT MOISTURE FROM THE EARLIER
MONSOONAL SURGE HELPING TO FUEL CONVECTION ACROSS MUCH OF THE CWA.
THE EC SOLUTION IS MORE CONTINGENT ON A WAVE APPROACHING THE AREA
THURSDAY AFTERNOON TO INCREASE CONVECTIVE COVERAGE ONCE AGAIN AFTER
TUESDAY.

LEANED TOWARD THE WETTER GFS SOLUTION WITH THE LONG TERM FORECAST
AND KEPT ELEVATED POPS THROUGH THE END OF THE FORECAST PERIOD. AS
WAS THE CASE YESTERDAY...CONFIDENCE IN THE LONG TERM PORTION OF THE
FORECAST IS LOWER THAN AVERAGE DUE TO THE RELIANCE ON SUBTLE
FEATURES MOVING AROUND THE PERIPHERY OF THE RIDGE.

&&

.FIRE WEATHER...A DRIER DAY IS ON TAP ACROSS MUCH OF THE DISTRICT
TODAY...WITH CONVECTION MAINLY LIMITED TO THE HIGHER TERRAIN AND
ADJACENT VALLEYS. MOISTURE WILL BEGIN TO INCREASE ACROSS THE
SOUTHERN PORTION OF THE STATE SATURDAY.  A SIGNIFICANT MONSOONAL
SURGE IS EXPECTED TO BEGIN SUNDAY ACROSS THE SOUTH...REACHING
NORTHERN UTAH MONDAY. THIS MONSOONAL SURGE WILL LAST THROUGH MIDWEEK
WITH WETTING RAINS LIKELY NEAR ANY SHOWERS OR THUNDERSTORMS. FIRE
WEATHER CONCERNS WILL BE MINIMAL THROUGH MUCH OF THE NEXT SEVEN DAYS
WITH MAINLY TERRAIN DRIVEN WINDS AND MOIST CONDITIONS EXPECTED.

&&

.AVIATION...LIGHT SOUTH TO SOUTHEASTERLY WINDS WILL CONTINUE AT THE
SLC TERMINAL THROUGH MUCH OF THE MORNING. EXPECT A WIND SHIFT TO THE
NORTH TO NORTHWEST BETWEEN 17-18Z. THERE IS A 20 PERCENT CHANCE THE
WIND SHIFT WILL OCCUR AS EARLY AS 16Z. DO NOT EXPECT ANY CONVECTION
TO IMPACT THIS TERMINAL THIS AFTERNOON AND EVENING.

&&

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

$$

CONGER/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)



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