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FNUS28 KWNS 052010
FWDD38

DAY 3-8 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0310 PM CDT SUN JUL 05 2015

VALID 071200Z - 131200Z

A BROAD CYCLONIC FLOW PATTERN IS EXPECTED TO PERSIST THROUGHOUT THE
FORECAST PERIOD ACROSS THE NORTHERN TIER OF THE CONUS...WITH WEAK
SHORTWAVE RIDGING IN PLACE ON D3/TUE IN THE SOUTHWESTERN CONUS JUST
DOWNSTREAM OF A CUT-OFF LOW OVER THE EASTERN PACIFIC.  MODELS HAVE
NOW COME INTO BETTER AGREEMENT THAT THIS LOW WILL MOVE SLOWLY INTO
CALIFORNIA WHILE WEAKENING/TRANSITIONING INTO AN OPEN WAVE THROUGH
D6/FRI.  AS THIS OCCURS...ENHANCED MID-LEVEL FLOW WILL DEVELOP OVER
THE SOUTHWESTERN CONUS.  MEANWHILE...AN UPPER RIDGE WILL STRENGTHEN
AND REMAIN NEARLY STATIONARY OVER THE SOUTHEASTERN CONUS.

...D3/TUE: PACIFIC NORTHWEST...
LOW PROBABILITIES OF ISOLATED DRY THUNDERSTORMS HAVE BEEN RETAINED
ACROSS PARTS OF OREGON FOR THIS FORECAST PERIOD.  CURRENT
INDICATIONS ARE THAT SLOW-MOVING THUNDERSTORMS WILL DEVELOP IN
TYPICAL TERRAIN-FAVORED AREAS AND PRODUCE WETTING RAINS DURING THE
AFTERNOON AND EARLY EVENING.  ALTHOUGH WEAK MID/UPPER FLOW AND
PRECIPITABLE WATER VALUES OF 0.75-1.1 INCH SUGGEST ONLY LIMITED DRY
THUNDERSTORM POTENTIAL...CONCERN REMAINS THAT PRE-EXISTING DRY FUELS
MAY IGNITE DUE TO LIGHTNING STRIKES THAT ARE DISPLACED FROM THE
HEAVIER THUNDERSTORM CORES.  GUSTY/ERRATIC SURFACE WINDS NEAR THE
STORMS MAY ALSO COMPLICATE ANY ONGOING FIRE SUPPRESSION EFFORTS.

A 40 PERCENT PROBABILITY AREA HAS ALSO BEEN INTRODUCED IN THE
COLUMBIA BASIN AND ADJACENT PARTS OF NORTHERN OREGON.  IN THIS
AREA...DRY FUELS AND A PRE-EXISTING DRY AIRMASS WILL COMBINE WITH
STRONG INSOLATION AND N/NWLY SURFACE FLOW TO RESULT IN ELEVATED FIRE
WEATHER CONDITIONS...WITH LOCALLY-CRITICAL FIRE WEATHER CONDITIONS
BRIEFLY POSSIBLE IN TERRAIN-FAVORED AREAS.

...D4/WED-D5/THU: PARTS OF SOUTHEASTERN NEVADA...NORTHWESTERN
ARIZONA...AND SOUTHWESTERN UTAH...
30-40 KNOT MID-LEVEL FLOW WILL OVERSPREAD THE REGION IN RESPONSE TO
A TIGHTENING GEOPOTENTIAL GRADIENT DUE TO THE SLOWLY EASTWARD-MOVING
CUT-OFF LOW OVER THE EASTERN PACIFIC.  INSOLATION/MIXING WILL
ENHANCE SOUTHWESTERLY SURFACE FLOW IN THESE REGIONS WHILE ALSO
RESULTING IN FALLING RH VALUES DURING THE AFTERNOON.  ALTHOUGH
ANTECEDENT RAINFALL MAY BE A MITIGATING FACTOR FOR A HIGHER FIRE
WEATHER THREAT...THE OVERALL PATTERN SUGGESTS AN INCREASING FIRE
WEATHER THREAT AND 40 PERCENT PROBABILITIES HAVE BEEN INTRODUCED FOR
EACH AFTERNOON TO ADDRESS THIS POTENTIAL.

..COOK.. 07/05/2015

...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...




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