Fire Weather Outlook Discussion
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000
FNUS22 KWNS 301612
FWDDY2

DAY 2 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1111 AM CDT TUE SEP 30 2014

VALID 011200Z - 021200Z

PREVIOUS FORECAST IS ON TRACK...NO CHANGES NEEDED.

..LEITMAN.. 09/30/2014

.PREV DISCUSSION... /ISSUED 0313 AM CDT TUE SEP 30 2014/

...SYNOPSIS...
IN THE MID LEVELS...MULTIPLE SHORTWAVE IMPULSES WILL TRACK THROUGH
BROADLY CYCLONIC FLOW COVERING AREAS FROM THE GREAT BASIN AND SWRN
CONUS TO THE PLAINS. AS THE SRN-MOST IMPULSE ADVANCES FROM THE CNTRL
GREAT BASIN AND SW STATES TO THE CNTRL/SRN ROCKIES...A MID-LEVEL
RIDGE WILL EDGE EWD TOWARD THE WEST COAST. SUBSIDENT NWLY FLOW ALOFT
ON THE BACKSIDE OF THE IMPULSE WILL /1/ ENHANCE SFC RIDGING ACROSS
PORTIONS OF THE CNTRL GREAT BASIN...AND /2/ BE ASSOCIATED WITH AN
INFLUX OF DRY TROPOSPHERIC AIR ACROSS PORTIONS OF THE W-CNTRL/SWRN
CONUS.

...PORTIONS OF CALIFORNIA...
THE PRESSURE GRADIENT ON THE WRN/SWRN FRINGES OF THE AFOREMENTIONED
REGIME OF CNTRL-GREAT-BASIN SFC RIDGING WILL MODESTLY ENHANCE NLY TO
ELY SFC WINDS ALONG THE CA COASTAL RANGES AND ADJACENT
FOOTHILLS...AS WELL AS ACROSS THE CENTRAL VALLEY OF CA. RELATED
DOWNSLOPE-FLOW-AIDED WARMING/DRYING IN THE BOUNDARY LAYER WILL
RESULT IN MINIMUM RH FROM THE UPPER SINGLE DIGITS TO THE TEENS IN
MANY AREAS...WITH POOR RH RECOVERY WED NIGHT...AS DEEP DRY AIR
OVERLIES THE REGION.

AN ELEVATED FIRE-WEATHER AREA HAS BEEN INCLUDED FOR PORTIONS OF THE
COASTAL RANGES AND ADJACENT FOOTHILLS OF SRN CA -- SPECIFICALLY
AFFECTING AREAS FROM ERN SANTA BARBARA COUNTY EWD ACROSS VENTURA
COUNTY INTO PORTIONS OF LOS ANGELES COUNTY AND SWRN SAN BERNARDINO
COUNTY. THIS IS WHERE THE LATEST MULTI-MODEL CONSENSUS SUGGESTS THE
EXISTENCE OF A RELATIVELY TIGHTER SFC PRESSURE GRADIENT CAPABLE OF
SUPPORTING SUSTAINED NELY TO ELY WINDS OF 15-20 MPH WITH HIGHER
GUSTS -- STRONGEST WINDS THROUGH FAVORED PASSES/CANYONS. AND...WITH
DOWNSLOPE FLOW BEING LOCALLY BOLSTERED IN THESE AREAS...AND WITH PW
VALUES FALLING TO AROUND ONE-QUARTER INCH...RH VALUES WILL LIKELY
FALL TO 8-15 PERCENT. GIVEN THE PRESENCE OF DRY FUELS...ELEVATED
FIRE WEATHER CONDITIONS ARE LIKELY TO DEVELOP THROUGH THE DAY ON WED
AND CONTINUE INTO WED NIGHT AS RH VALUES REMAIN LOW. LOCALIZED
BORDERLINE CRITICAL FIRE WEATHER CONDITIONS MAY
EVOLVE...PARTICULARLY DURING WED NIGHT AS THE SFC PRESSURE GRADIENT
POTENTIALLY BECOMES REINFORCED. HOWEVER...CONFIDENCE IN A MORE
WIDESPREAD RISK FOR STRONG SUSTAINED WIND SPEEDS IS TOO LIMITED FOR
CRITICAL DELINEATION...IN THE ABSENCE OF A TIGHTER SFC PRESSURE
GRADIENT.

ELSEWHERE...GENERALLY SPOTTY/BRIEF/MARGINAL ELEVATED FIRE WEATHER
CONDITIONS MAY ENSUE...ESPECIALLY AROUND THE HILLS SURROUNDING THE
SAN FRANCISCO BAY AREA AND LOCATIONS SWD TO THE INTERNATIONAL
BORDER...AS WELL AS ACROSS THE CENTRAL VALLEY OF CA...WHERE DRY
FUELS EXIST. HOWEVER...SUSTAINED WIND SPEEDS SHOULD GENERALLY BE
BELOW 15 MPH -- WITHOUT A TIGHTER SFC PRESSURE GRADIENT -- TO
MITIGATE THE FIRE-WEATHER RISK. THIS PRECLUDES THE INTRODUCTION OF
ANY ADDITIONAL FIRE-WEATHER HIGHLIGHTS.

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



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