Fire Weather Outlook Discussion
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FNUS22 KWNS 271921
FWDDY2

DAY 2 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0220 PM CDT FRI MAR 27 2015

VALID 281200Z - 291200Z

...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF ERN WY...FAR SW NEB
PANHANDLE...FAR SE MT...

THE ELEVATED AREA HAS BEEN EXTENDED WWD ACROSS PORTIONS OF MT AND
WY. ADDED AREAS WILL BE IN PROXIMITY TO STRONG TROPOSPHERIC FLOW
CAPABLE OF SUPPORTING SUSTAINED WLY TO WNWLY SFC WINDS OF 25-35 MPH
AND HIGHER GUSTS PER THE LATEST MULTI-MODEL CONSENSUS. THE PRESENCE
OF MID/HIGH-LEVEL CLOUDS WILL STUNT SFC WARMING TO SOME EXTENT.
HOWEVER...STRONG DOWNSLOPE-FLOW-INDUCED WARMING/DRYING AND ENHANCED
VERTICAL MIXING SHOULD PROMOTE SUFFICIENT RH REDUCTIONS TO WARRANT
ELEVATED DESIGNATION. RH VALUES ARE EXPECTED TO FALL TO AROUND 20-25
PERCENT ACROSS THE ADDED AREAS AS TEMPERATURES CLIMB INTO THE
LOWER/MIDDLE 60S /AT THE RELATIVELY LOWER ELEVATIONS/. THIS IS
SUPPORTED BY THE LATEST GFS-MOS GUIDANCE THAT REFLECTS WARMER/DRIER
SFC CONDITIONS THAN NAM/GFS FORECAST SOUNDINGS /WHICH OFTEN EXHIBIT
COOL AND MOIST BIASES AT THE SFC IN THESE REGIMES/. DRY FINE FUELS
WILL SUPPORT THE POTENTIAL FOR FIRE GROWTH ACROSS THE AREAS ADDED TO
ELEVATED DESIGNATION. THE LACK OF EVEN STRONGER SFC HEATING OWING TO
THE PRESENCE OF CLOUDS SHOULD PREVENT RH VALUES FROM BECOMING
CRITICALLY LOW ACROSS AREAS ADDED TO ELEVATED DESIGNATION.

OTHERWISE...THE REMAINDER OF THE FORECAST IS ON TRACK BASED ON THE
LATEST AVAILABLE MODEL GUIDANCE...AND NO ADDITIONAL CHANGES HAVE
BEEN MADE.

..COHEN.. 03/27/2015

.PREV DISCUSSION... /ISSUED 0313 AM CDT FRI MAR 27 2015/

...SYNOPSIS...
OVERALL UPPER PATTERN IS EXPECTED TO LOSE AMPLITUDE THROUGHOUT THE
PERIOD AS THE ERN CONUS TROUGH GRADUALLY MOVES EWD /EVENTUALLY
MOVING OFF THE ERN SEABOARD VERY LATE IN THE PERIOD/ AND THE UPPER
RIDGE IN ITS WAKE OVER THE PLAINS DAMPENS IN RESPONSE TO A SHORTWAVE
TROUGH MOVING THROUGH THE NRN ROCKIES AND INTO THE CNTRL PLAINS.
GENERALLY WEAK...NEARLY-ZONAL FLOW IS EXPECTED W OF THE ROCKIES.
SURFACE PATTERN ACROSS THE ERN CONUS WILL BE DOMINATED BY A LARGE
RIDGE MOVING FROM THE GREAT LAKES SEWD INTO THE CNTRL APPALACHIANS.
A SURFACE LOW WILL MOVE EWD ACROSS THE CANADIAN PRAIRIE PROVINCES AS
AN ASSOCIATED COLD FRONT MOVES THROUGH THE PLAINS AFTER 00Z/SUN.

...NRN/CNTRL HIGH PLAINS...
SURFACE PRESSURE GRADIENT ACROSS THE AREA IS EXPECTED TO TIGHTEN
THROUGHOUT THE DAY AS THE COMBINATION OF THE APPROACHING COLD FRONT
AND ANTECEDENT LEE TROUGHING HELPS LOWER PRESSURES WHILE THE SURFACE
HIGH REMAINS OVER THE WRN OH VALLEY. THIS ENHANCED SURFACE PRESSURE
GRADIENT COUPLED WITH INCREASING WLY FLOW ALOFT AHEAD OF THE
APPROACHING SHORTWAVE TROUGH WILL HELP SUPPORT SUSTAINED WLY WINDS
AROUND 20-25 MPH WITH GUSTS OVER 35 MPH POSSIBLE. WIND SPEEDS MAY BE
A BIT LOWER FARTHER S INTO NE CO WHERE THE GRADIENT IS MORE RELAXED.
CRITICAL FIRE WEATHER CONDITIONS APPEAR LIKELY OVER MOST OF ERN
WY...FAR SW NEB PANHANDLE...AND SE MT WHERE THE GUSTY WINDS WILL
OVERLAP RH VALUES BELOW 20 PERCENT. ELEVATED FIRE WEATHER CONDITIONS
ARE EXPECTED ELSEWHERE ACROSS THE REGION WITH WINDS SPEEDS BELOW 20
MPH AS THE LIMITING FACTOR ACROSS WRN SD...MOST OF THE NEB
PANHANDLE/WRN NEB...AND NE CO. MIN RH VALUES ABOVE 20 PERCENT IS THE
LIMITING FACTOR FOR E-CNTRL/NE MT.

...CNTRL FL...
POST-FRONTAL CONDITIONS WILL LIKELY RESULT IN NWLY WINDS AROUND 15
MPH AMIDST MIN RH VALUES BELOW 35 PERCENT. THESE METEOROLOGICAL
CONDITIONS USUALLY MERIT AT LEAST AN ELEVATED FIRE WEATHER THREAT.
HOWEVER...UNRECEPTIVE FUELS WILL TEMPER ANY POTENTIAL FIRE WEATHER
RISK...PRECLUDING THE NEED FOR AN ELEVATED AREA.

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



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