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FNUS28 KWNS 031936
FWDD38

DAY 3-8 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0236 PM CDT FRI JUL 03 2015

VALID 051200Z - 111200Z

THE OVERALL FLOW PATTERN AT THE BEGINNING OF THE FORECAST PERIOD
WILL BE CHARACTERIZED BY A RIDGE OVER A LARGE PART OF THE WESTERN
CONUS...AND A BELT OF ENHANCED QUASI-ZONAL FLOW FROM THE NORTHERN
ROCKIES INTO THE NORTHERN GREAT PLAINS.  A WEAK UPPER TROUGH WILL
MOVE VERY LITTLE ACROSS THE SOUTHERN APPALACHIANS FROM D3/SUN
THROUGH D5/TUE...AFTER WHICH IT WILL MERGE WITH A LARGER-SCALE
SHORTWAVE TROUGH AXIS IN THE NORTHERN STREAM.  THE WESTERN RIDGE
WILL BREAK DOWN BEGINNING D5/TUE AS A SLOW-MOVING UPPER TROUGH MOVES
INTO NORTHERN CALIFORNIA.  MODEL DIFFERENCES REMAIN REGARDING THE
SPEED OF THIS TROUGH AS IT MOVES EAST...LOWERING PREDICTABILITY
BEYOND D6/WED.

...D3/SUN THROUGH D5/TUE: PACIFIC NORTHWEST...
LOW CHANCES OF ISOLATED DRY THUNDERSTORMS HAVE BEEN MAINTAINED FOR
THIS PERIOD.  ALTHOUGH THE UPPER FLOW OVER THE REGION REMAINS
WEAK/CONVOLUTED...STRENGTHENING INSTABILITY DUE TO INSOLATION WILL
RESULT IN SLOW-MOVING THUNDERSTORMS DEVELOPING ALONG HIGHER TERRAIN
AND RIDGELINES ON EACH AFTERNOON.  PRECIPITABLE WATER VALUES ARE
EXPECTED TO REMAIN ON THE MARGINS FOR A MORE WIDESPREAD DRY
THUNDERSTORM THREAT /AROUND 0.8-1.0 INCH/ BUT GIVEN DRY FUEL
CONDITIONS...ANY DRY AREAS NEAR THUNDERSTORMS WILL BE SUSCEPTIBLE TO
LIGHTNING-INDUCED FIRE STARTS.  AFTERNOON RH VALUES SHOULD MEET
CRITICAL CRITERIA EACH AFTERNOON...BUT WEAK LARGE-SCALE FLOW SHOULD
LIMIT A HIGHER FIRE WEATHER THREAT TO ONLY LOCALIZED AREAS
INFLUENCED BY TERRAIN.

...D7/THU: SOUTHERN GREAT BASIN...
MID-LEVEL FLOW WILL STRENGTHEN AS AN UPPER LOW ENTERS NORTHERN
CALIFORNIA.  GIVEN THE PRE-EXISTING DRY AIRMASS IN PLACE AND STRONG
AFTERNOON SOLAR HEATING...AN INCREASED FIRE WEATHER THREAT IS
POSSIBLE.  ONE MITIGATING FACTOR FOR INTRODUCING PROBABILITIES FOR
THIS FORECAST REMAINS DIFFERENCES AMONG MODEL GUIDANCE IN THE SPEED
OF THIS UPPER LOW AS IT MOVES EASTWARD TOWARD THE PACIFIC COAST.  AS
TIMING BECOMES MORE CERTAIN AND PRECIPITATION POTENTIAL BECOMES MORE
CLEAR...PROBABILITIES MAY NEED TO BE INTRODUCED IN PARTS OF THE AREA
IN LATER FORECASTS.

..COOK.. 07/03/2015

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



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