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FNUS28 KWNS 072015
FWDD38

DAY 3-8 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0315 PM CDT TUE JUL 07 2015

VALID 091200Z - 151200Z

A CLOSED UPPER LOW WILL BE LOCATED ALONG THE WEST COAST AT THE
BEGINNING OF THE FORECAST PERIOD...WITH BROAD ZONAL FLOW DOWNSTREAM
ACROSS THE CENTRAL PLAINS EASTWARD INTO THE NORTHEASTERN CONUS.
WITH TIME...THIS UPPER LOW WILL WEAKEN WHILE EVOLVING INTO AN OPEN
WAVE...WHILE ENHANCING MID-LEVEL FLOW OVER PARTS OF THE
WESTERN/SOUTHWESTERN CONUS THROUGHOUT THE FORECAST PERIOD.  ANOTHER
WAVE WILL DIG SOUTHEASTWARD FROM THE NORTHEASTERN PACIFIC TOWARD
BRITISH COLUMBIA IN THE D5/SAT-D7/MON TIME FRAME...ALTHOUGH GUIDANCE
IS NOT VERY CONSISTENT WITH ITS EVOLUTION AND ASSOCIATED WIND/HEIGHT
FIELDS ALOFT.  HOWEVER...MODELS ARE CONSISTENT IN WESTWARD
DEVELOPMENT OF AN UPPER RIDGE CENTERED OVER THE DEEP SOUTH ON
D5/SAT...SOUTHERN PLAINS ON D6/SUN...AND THE SOUTHERN ROCKIES BY
D7/MON.

...SOUTHERN GREAT BASIN...
DESPITE THE FAVORABLE RIDGE-BREAKDOWN PATTERN FOR AN INCREASED FIRE
WEATHER THREAT IN THE WEST...COPIOUS AMOUNTS OF MID-LEVEL MOISTURE
AND WETTING RAINS FROM THUNDERSTORMS OVER THE PAST WEEK WILL TEMPER
ANY LARGE-SCALE FIRE WEATHER CONCERNS OVER A LARGE PART OF THE
SOUTHWESTERN U.S. THROUGHOUT THE PERIOD.  SOME RISK FOR AT LEAST AN
ELEVATED FIRE WEATHER THREAT WILL EXIST DUE TO 15-20 MPH SSWLY
SURFACE FLOW IN THE AREA ON D3/THU...BUT LATEST GUIDANCE SUGGESTS
AFTERNOON RH WILL BE MARGINAL AT BEST FOR A MORE EXTENSIVE THREAT.
FUEL RECEPTIVENESS IS ALSO IN QUESTION GIVEN THE ANTECEDENT RAINFALL
OVER PARTS OF THE AREA...AND A FEW ISOLATED THUNDERSTORMS ARE ALSO
POSSIBLE ON D3/THU.  THE 40 PERCENT DELINEATION ISSUED IN
YESTERDAY/S OUTLOOK HAS BEEN RETAINED FOR THIS FORECAST DESPITE
AFOREMENTIONED DETRACTORS FOR A HIGHER FIRE WEATHER THREAT.
ATMOSPHERIC TRENDS WILL CONTINUE TO BE MONITORED FOR THE POTENTIAL
FOR ELEVATED FIRE WEATHER CONDITIONS IN LATER FORECASTS.

...NORTHERN ROCKIES...
VERY DRY FUELS SUPPORTIVE OF RAPID FIRE GROWTH HAVE DEVELOPED IN THE
NORTHERN ROCKIES...AND ALTHOUGH WETTING STORMS HAVE OCCURRED IN A
FEW AREAS IN RECENT DAYS...A FEW LIGHTNING-INDUCED FIRES HAVE
OCCURRED IN AREAS THAT HAVE RECEIVED MINIMAL RAINFALL DISPLACED FROM
HEAVIER THUNDERSTORM DOWNDRAFTS.  A THREAT FOR CONTINUED
LIGHTNING-INDUCED ACTIVITY WILL EXIST ON D3/THU IN PARTS OF THE
NORTHERN ROCKIES...BUT CONFIDENCE IN A SPECIFIC AREA OF DRY
THUNDERSTORM POTENTIAL REMAINS TOO LOW TO ISSUE PROBABILITIES IN
THIS FORECAST.  THIS WILL BE MONITORED IN FUTURE OUTLOOKS.

...PACIFIC NORTHWEST...
PARTS OF THIS REGION ARE EXPECTED TO REMAIN RELATIVELY RAIN-FREE IN
THE NEXT FEW DAYS...WHICH WILL CONTINUE TO RESULT IN DRY FUELS
SUPPORTIVE OF FIRE GROWTH ESPECIALLY IN THE LEE OF THE CASCADES.
WEAK FLOW SHOULD LIMIT A MORE EXTENSIVE THREAT UNTIL D5/SAT...WHEN
MODELS GENERALLY INCREASE DRY DOWNSLOPE FLOW OVER THE REGION IN
RESPONSE TO THE APPROACHING STORM SYSTEM WEST OF BRITISH COLUMBIA.
CONFIDENCE IN THE DETAILS OF THIS EVOLVING THREAT IS TOO LOW FOR
PROBABILITIES AT THIS TIME...AS MODELS ARE NOT CONSISTENT IN THE
EXTENT OF STRENGTHENING FLOW ACROSS THE REGION.  THIS AREA WILL BE
MONITORED FOR AN INCREASING FIRE WEATHER THREAT IN FUTURE OUTLOOKS.

..COOK.. 07/07/2015

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




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