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000
FXUS65 KSLC 170848
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
248 AM MDT MON JUN 17 2013

.SYNOPSIS...A WARM AND DRY SOUTHWEST FLOW ALOFT WILL EXIST ACROSS
THE GREAT BASIN EARLY THIS WEEK. A DRY COLD FRONT WILL PUSH ACROSS
NORTHERN AND CENTRAL UTAH ON WEDNESDAY. HIGH PRESSURE WILL BUILD
INTO THE AREA ONCE AGAIN FOR LATE IN THE WEEK.

&&

.DISCUSSION...WATER VAPOR LOOP SHOWS A BROAD CLOSED LOW OFF THE
PACIFIC NORTHWEST...WITH WEAK DISTURBANCES EMBEDDED IN SOUTHWEST
FLOW ALOFT FROM THE EASTERN PACIFIC THROUGH CENTRAL CALIFORNIA AND
THE EASTERN GREAT BASIN. ACARS 400-250MB WIND OBSERVATIONS PLACE A
50-65KT WESTERLY JET FROM SOUTH CENTRAL CALIFORNIA INTO ARIZONA.
MEANWHILE...A 75-95KT CYCLONICALLY CURVED JET WAS OVER THE PACIFIC
NORTHWEST. RAP...GOES...GPS SENSORS...AND 00Z SLC RAOB INDICATE
PRECIPITABLE WATER VALUES ARE IN THE 0.10" AND 0.35" RANGE.

REMOVED MENTION OF ISOLATED POPS MONDAY THROUGH WEDNESDAY FOR THE
NORTH. VERY DRY ENVIRONMENT IN PLACE. HOWEVER WITH THE PASSING
DISTURBANCES AND DAYTIME HEATING...CONVECTION STILL POSSIBLE ACROSS
THE RAFT RIVER MOUNTAINS...UINTA MOUNTAINS AND SOUTHWEST WYOMING.
HAVE MENTIONED DRY THUNDERSTORMS FOR THESE AREAS EACH AFTERNOON AND
EVENING. THIS IS SUPPORTED BY THE SHORT RANGE ENSEMBLE INSTABILITY
PROBABILITIES AND SIMULATED REFLECTIVITY FROM THE LOCAL 4KM WRF-ARW.
INSTEAD OF ANY RAINFALL...ISOLATED LIGHTNING AND LOCAL
GUSTY/ERRATIC WINDS WILL BE THE BIGGEST THREATS FROM THIS ACTIVITY.

VERY DRY AIRMASS IN PLACE. WHEN COMBINED WITH GUSTY SOUTHWEST WINDS
AHEAD OF THE NEXT COLD FRONT TUESDAY/WEDNESDAY...FIRE WEATHER IS
BIGGEST THREAT. SEE FIRE WEATHER DISCUSSION BELOW. THE COLD FRONT
WILL ALSO BRING COOLER TEMPERATURES TO THE NORTH MID TO LATE WEEK.

BOTH THE GFS PRECIPITABLE WATER...AND EUROPEAN 850-500MB SPECIFIC
HUMIDITY INDICATE DRY AIRMASS REMAINING IN PLACE THROUGH THE
EXTENDED FORECAST SO KEPT POPS BELOW MENTIONABLE CRITERIA. THIS ALSO
LINES UP WITH THE NAEFS PRECIPITABLE WATER ANOMALY PRODUCT.

TEMPERATURES ACROSS THE NORTH LOOK TO GRADUALLY REBOUND LATE WEEK
AND INTO NEXT WEEKEND WITH GOOD CONSISTENCY AT 700MB BETWEEN
GFS/EUROPEAN (CANADIAN WAS A COLDER OUTLIER). PATTERN RELOADS NEXT
WEEK WITH ANOTHER CLOSED LOW HEADING TOWARD THE PACIFIC
NORTHWEST...ALTHOUGH IT MAY BE FURTHER WEST ALLOWING THE RIDGE TO
BUILD INTO THE REGION WITH MORE AUTHORITY. PERHAPS THIS LEADS TO A
BIT LESS SOUTHWEST WIND...A BIT MORE MOISTURE FOR CONVECTION AND
HOTTER TEMPERATURES HEADING INTO THE SECOND HALF OF NEXT WEEK.

&&

.AVIATION...THE SLC TERMINAL WILL SEE VFR CONDITIONS THROUGHOUT THE
DAY WITH CLEAR SKIES. LIGHT EASTERLY WINDS ARE EXPECTED TO SHIFT TO
THE SOUTHEAST BY 12Z. THEY SHOULD THEN SHIFT TO THE NORTHWEST
BETWEEN 18Z AND 20Z.

&&

.FIRE WEATHER...HIGH PRESSURE WILL REMAIN OVER THE FIRE DISTRICT
TODAY...RESULTING IN CONTINUED WARM AND DRY CONDITIONS. SOUTHWEST
FLOW WILL INCREASE TUESDAY AND WEDNESDAY AS A PACIFIC STORM SYSTEM
APPROACHES...AND THIS IS EXPECTED TO CAUSE SEVERE FIRE WEATHER
CONDITIONS WHERE FUELS ARE DRY. THE STORM SYSTEM WILL SLOWLY GRAZE
THE STATE WEDNESDAY THROUGH SATURDAY...PUSHING A DRY COLD FRONT INTO
NORTHERN UTAH WEDNESDAY AND THURSDAY. THE INFLUENCE OF THE STORM
SYSTEM WILL KEEP SOUTHWEST WINDS ELEVATED...AT LEAST OVER SOUTHERN
UTAH...THROUGH SATURDAY. THIS WILL KEEP THE THREAT OF CRITICAL FIRE
WEATHER CONDITIONS IN THE FORECAST FOR MUCH OF THE WEEK.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
     EVENING BELOW 7000 FEET FOR UTZ489.

     FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
     EVENING FOR UTZ497-498.

     FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
     EVENING BELOW 9000 FEET FOR UTZ496.

     FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
     EVENING BELOW 6000 FEET FOR UTZ495.

WY...NONE.
&&

$$

PUBLIC...ROGOWSKI
FIRE WEATHER...TRAPHAGAN
AVIATION...TRAPHAGAN

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)