Area Forecast Discussion
Issued by NWS Salt Lake City, UT

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KSLC 032208
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
408 PM MDT FRI JUL 3 2015

.SYNOPSIS...HIGH PRESSURE ALOFT ACROSS THE GREAT BASIN WILL
GRADUALLY SHIFT INTO THE SOUTHERN ROCKIES THIS WEEKEND ALLOWING
DEEP MOISTURE TO SURGE NORTH AND EAST THROUGH THAT TIME.
SOMEWHAT COOLER TEMPERATURES WILL MOVE INTO THE REGION LATE IN
THE WEEKEND THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...AFTERNOON WATER VAPOR AND H5 ANALYSIS INDICATE A
SLIGHT NORTHEAST SHIFT THE RIDGE AXIS ASSOCIATED WITH THE
DOMINANT HIGH PRESSURE IN PLACE...WITH LOCATION NEARLY BISECTING
THE STATE FROM SOUTHEAST TO NORTHWEST ATTM. SAID RIDGE AXIS
REMAINS THE DELINEATION BETWEEN A DRIER AND MORE SUPPRESSED
AIRMASS TO THE NORTH AND EAST...AND A DEEPLY MOIST AIRMASS BENEATH
AND TO ITS SOUTH AND WEST. ISOLATED TO WIDELY SCATTERED CONVECTION
HAS ONCE AGAIN FORMED OVER THE SOUTHERN MOUNTAINS...WITH ANOTHER
CLUSTER MOVING INTO THE WEST DESERTS OUT OF NORTHEASTERN NEVADA
WITHIN THE MORE MOISTURE RICH AND LESS SUPPRESSED ENVIRONMENT.
THOSE TWO AREAS WILL REMAIN THE FOCUS FOR CONVECTION THROUGH THIS
EVENING BEFORE DISSIPATING WITH LOSS OF SOLAR INPUT/HEATING BUT
ANTICIPATE A FAIRLY DECENT MID LEVEL CLOUD DECK TO REMAIN IN
PLACE.

FOCUS TURNS TO THE EVOLUTION OF THE HIGH OVER THE NEXT 24 HOURS
AND THE PLACEMENT OF THE AFOREMENTIONED SHEAR AXIS. MODELS
CONTINUE TO PORTRAY THE CENTER OF THE HIGH SHIFTING SOUTH AND EAST
INTO WESTERN COLORADO BY SUNDAY MORNING ALLOWING THE AXIS TO
SHIFT MORE TO THE NORTH AND EAST. THE MORE FAVORABLE CONVECTIVE
ENVIRONMENT WILL SHIFT AS SUCH AND LIKELY BE ON THE DOORSTEP OF
THE WASATCH FRONT/NORTHERN MOUNTAINS BY THIS TIME TOMORROW.
ADDITIONALLY GUIDANCE CONTINUES TO INDICATE A STRENGTHENING
DISTURBANCE WITHIN THE RETURN FLOW WILL RESIDE OVER WESTERN
ARIZONA TOMORROW AFTERNOON...TRACKING NORTH. PRESENCE OF LARGER
SCALE FORCING ALONG ITS LEADING EDGE WILL PROVIDE AN ADDITIONAL
TRIGGER AND LIFT LATE DAY AND ANTICIPATE GREATER AREAL COVERAGE OF
STORMS BEGINNING TOMORROW AFTERNOON. TIMING AND STRENGTH OF THIS
FEATURE...WHICH CAN BE HARD TO RESOLVE IN MODELS...AND CLOUD COVER
WILL BE THE KEY TO THE EXTENT OF CONVECTION TOMORROW EVE/NIGHT AND
SOME SPREAD DOES EXIST REGARDING THIS...BUT FELT CONFIDENT TO
RAISE POPS TO SCATTERED COVERAGE WORDING MOST AREAS TOMORROW EVE
THROUGH SUNDAY AS THIS WAVE PASSES. TEMPS ALL AREAS WILL BE
NOTABLY COOLER BEGINNING SUNDAY AND GETTING OUT OF THE 80S IN KSLC
MAY BE CHALLENGING.

CONVERGENT NEAR WESTERLY FLOW WILL MAINTAIN DEEP MOISTURE OVER THE
AREA INTO EARLY NEXT WEEK AS THE AFOREMENTIONED WAVE GETS PICKED
UP BY THE NORTHERN BRANCH AND EXITS EAST. FOCUSED MOISTURE
CONVERGENCE AND GREATEST CONVECTION POTENTIAL APPEARS TO BE
FOCUSED OVER THE NORTHERN HALF OF THE FORECAST AREA AT THAT TIME.

.LONG TERM (AFTER 06Z TUESDAY)...MOISTURE REMAINS IN PLACE OVER THE
FORECAST AREA ON TUESDAY...ALLOWING FOR ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS...PRIMARILY DURING THE EVENING. THE MOISTURE WILL ALSO
KEEP MAXES AROUND SEASONAL NORMALS ACROSS THE STATE.

DRIER AIR IS PROGGED TO START TO NOSE INTO WESTERN UTAH BEGINNING
WEDNESDAY AS A PACIFIC LOW APPROACHES THE CALIFORNIA COAST. GLOBAL
MODELS ALL INDICATE THIS SYSTEM WILL MOVE ONSHORE AND EVENTUALLY
AFFECT THE FORECAST AREA. GFS MOVES THE SYSTEM ONSHORE EARLY
THURSDAY...WHILE THIS OCCURS A BIT LATER IN THE GFS. BOTH MODELS
MOVE THE SYSTEM OVER NORTHERN UTAH AS IT WEAKENS NEXT
WEEKEND...SHOWING UNUSUALLY GOOD AGREEMENT THAT FAR OUT. FOR
NOW...HAVE INDICATED A DRYING TREND FOR THE LATTER HALF OF THE
UPCOMING WORK WEEK...WITH A SLIGHT WARMING TREND IN TEMPERATURES.

&&

.AVIATION...VFR CONDITIONS AT KSLC WILL PREVAIL THROUGH THE TAF
PERIOD...WITH NORTHWEST WINDS SWITCHING BACK TO THE SOUTH BETWEEN
03Z AND 04Z.

&&

.FIRE WEATHER...ISOLATED TO WIDELY SCATTERED THUNDERSTORMS WILL
CONTINUE TO BRING SPOTTY WETTING RAINS OVER PORTIONS OF THE FAR
SOUTH AND WEST THROUGH THIS EVENING. ELSEWHERE DRY AND HOT
CONDITIONS WILL CONTINUE TO DOMINATE UNTIL THE MOISTURE OVER THE
SOUTH AND WEST BEGINS TO SURGE NORTH AND EAST TOMORROW THROUGH
TOMORROW NIGHT. AREAL COVERAGE OF THUNDERSTORMS AND ASSOCIATED
WETTING RAIN POTENTIAL WILL TREND TO INCREASE EACH DAY THROUGH
SUNDAY AS SUCH...THEN WILL REMAIN IN PLACE THROUGH THE MIDWEEK
TIMEFRAME BRINGING A RELATIVELY WET AND COOLER PERIOD TO THE
DISTRICT THROUGH THAT TIME.

A DRYING SOUTHWESTERLY FLOW WILL DEVELOP LATE WEEK...WITH
POTENTIAL FOR MUCH DRIER CONDITIONS AND LOCALLY GUSTY WINDS.

&&

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

$$

MERRILL/TRAPHAGAN/SEAMAN


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)



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.