SPC Day 1 Fire Weather Outlook

DAY 1 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0349 AM CDT TUE MAY 14 2013

VALID 141200Z - 151200Z

...CRITICAL FIRE WEATHER AREA FOR EXTREME NE NEB...ERN SD...NRN
IA...SRN MN...

...SYNOPSIS...
UPPER TROUGH OFF THE E COAST WILL CONTINUE NEWD WHILE THE POLAR JET
DE-AMPLIFIES. SHORTWAVE TROUGH EMBEDDED WITHIN THE NEAR-ZONAL FLOW
OF THE JET WILL TRACK QUICKLY EWD...MOVING FROM SRN SK/NE MT THROUGH
SRN MB/NRN ND AND INTO WRN ONTARIO THROUGHOUT THE PERIOD. COLD FRONT
ASSOCIATED WITH THIS SHORTWAVE TROUGH WILL MOVE ACROSS THE ERN
DAKOTAS BY THE EARLY AFTERNOON AND THROUGH MUCH OF THE MID MO VALLEY
AND SRN MN BY THE END OF THE PERIOD. DEWPOINTS AHEAD OF THIS FRONT
HAVE BEEN CONSISTENTLY OVER-FORECAST BY ALMOST ALL GUIDANCE
/DISCUSSED IN MORE DETAIL IN THE SUB-SECTION BELOW/. ELSEWHERE...AN
UPPER LOW WITHIN THE SRN STREAM...CENTERED OVER THE CNTRL GULF OF CA
PER EARLY MORNING SATELLITE IMAGERY...WILL DRIFT EWD ACROSS NRN
MEXICO AND INTO TX WITH ISOLATED TSTM ACTIVITY POSSIBLE ACROSS W TX
LATE IN THE PERIOD.

...EXTREME NE NEB...ERN SD...NRN IA...SRN MN...
SURFACE TROUGH AND COLD FRONT ASSOCIATED WITH THE PREVIOUSLY
DISCUSSED SHORTWAVE TROUGH WILL PROGRESS ACROSS THE DAKOTAS AND
UPPER MIDWEST. A TIGHT SURFACE PRESSURE GRADIENT WILL RESULT IN SWLY
WINDS FROM 20-25 MPH WITH GUSTS UP TO 35 MPH AHEAD OF THE FRONT.
WINDS WILL QUICKLY SHIFT NWLY AFTER FROPA...WITH WIND SPEEDS
GENERALLY AROUND 15-20 MPH WITH GUSTS UP TO 30 MPH. DEEP BOUNDARY
LAYER MIXING AMIDST STRONG DOWNSLOPING SWLY WINDS AND THE PRESENCE
OF AN ABNORMALLY WARM THERMAL RIDGE /850 MB TEMPERATURES FROM 20-25
DEG C/ WILL RESULT IN HIGHS IN THE MID TO UPPER 90S /APPROACHING OR
EXCEEDING RECORD VALUES FOR MANY LOCATIONS/. AS MENTIONED IN THE
SYNOPSIS...MODEL DEWPOINTS FROM MOST GUIDANCE HAVE BEEN CONSISTENTLY
TOO HIGH. NAM...GFS...AND SREF MEAN HAVE DEWPOINTS GENERALLY IN THE
MID 50S. THE DEWPOINTS APPEAR PARTICULARLY ERRONEOUS IN N-CNTRL/NE
IA AND S-CNTRL/SE MN WHERE MODEL DEWPOINTS ARE NEAR 60 AT 21Z. IN
CONTRAST...SHORT-TERM GUIDANCE PROVIDED BY THE RAP APPEARS TOO DRY
WITH DEWPOINTS GENERALLY IN THE LOW TO MID 30S. GIVEN THE DEPTH OF
THE MIXING...DEWPOINTS IN THE MID 40S APPEAR MOST LIKELY. THESE
VALUE WILL RESULT IN RH VALUES FROM 15 TO 20 PERCENT. THE
COMBINATION OF ALL OF THESE FACTORS WILL RESULT IN A CRITICAL FIRE
WEATHER THREAT ACROSS THE REGION.

...ERN ND/NWRN MN...
SUSTAINED WLY WINDS NEAR 30 MPH WITH GUSTS TO 40 MPH ARE ANTICIPATED
IN THE WAKE OF THE COLD FRONT ACROSS ERN ND. TEMPERATURES IN THE
UPPER 70S AND DEWPOINTS IN THE MID 30S WILL RESULT IN RH VALUES
GENERALLY AROUND 20-25 PERCENT. RH VALUES MAY BRIEFLY DROP BELOW 20
PERCENT FOR A HOUR OR TWO DURING THE LATE AFTERNOON. AS
SUCH...ELEVATED TO BRIEFLY/LOCALLY CRITICAL FIRE WEATHER CONDITIONS
ARE EXPECTED.

...SERN CO...WRN/CNTRL KS...TX/OK PANHANDLES...NERN NM...
LEE TROUGH ACROSS THE CNTRL HIGH PLAINS IN TANDEM WITH THE SURFACE
TROUGH ASSOCIATED WITH THE COLD FRONT MOVING ACROSS THE
DAKOTAS/UPPER MIDWEST WILL SUPPORT ENHANCED SLY FLOW ACROSS MUCH OF
THE SRN PLAINS AND SRN PORTIONS OF THE CNTRL PLAINS. WIND SPEEDS
WILL GENERALLY BE AROUND 20 MPH WITH THE STRONGEST WINDS EXPECTED
ACROSS CNTRL KS. HIGHS NEAR 90 AND DEWPOINTS GENERALLY AROUND 30
WILL SUPPORT RH VALUES FROM 10-20 PERCENT /WITH THE LOWEST VALUES
FROM NERN NM NEWD THROUGH THE OK PANHANDLE AND INTO SWRN KS/. THE
BEST JUXTAPOSITION OF STRONG WINDS AND LOW RH IS ACROSS CNTRL KS BUT
FUEL GUIDANCE INDICATES GENERALLY MOIST FUELS IN THIS AREA. SW OF
THIS AREA...WIND SPEEDS AT OR ABOVE 20 MPH MAY OCCUR FOR A FEW HOURS
DURING THE LATE AFTERNOON BUT WINDS GENERALLY LESS THAN 20 MPH ARE
EXPECTED. AS A RESULT...ELEVATED TO LOCALLY CRITICAL FIRE WEATHER
CONDITIONS ARE ANTICIPATED. AN UPGRADE TO CRITICAL MAY BE NEEDED IF
GUIDANCE/OBSERVATIONS INDICATE WIND SPEEDS OVER 20 MPH LASTING
LONGER THAN 3 HOURS.

...SRN NV...
ENHANCED MID-LEVEL WINDS ARE EXPECTED ACROSS SRN NV AS A SHORTWAVE
TROUGH APPROACHES THE REGION. THESE ENHANCED WINDS IN CONJUNCTION
WITH A DEEPLY MIXED BOUNDARY LAYER... AFTERNOON TEMPERATURES IN THE
UPPER 80S/LOW 90S...AND RH VALUES IN THE SINGLE DIGITS WILL RESULT
IN LOCALLY ELEVATED FIRE WEATHER THREAT.

..MOSIER.. 05/14/2013

...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...
via SPC Forecast Products http://www.spc.noaa.gov/products/fire_wx/fwdy1.html