National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FNUS28 KWNS 171924
FWDD38

DAY 3-8 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0223 PM CDT MON JUN 17 2013

VALID 191200Z - 251200Z

A MID-LEVEL CYCLONE WILL SLOWLY ADVANCE EWD FROM THE PACIFIC NW TO
THE NRN ROCKIES FOR MID/LATE THIS WEEK. SHORTWAVE IMPULSES PIVOTING
AROUND THE SRN SEMICIRCLE OF THE CYCLONE WILL EXTEND ENHANCED
CYCLONIC FLOW INTO THE SWRN STATES THROUGH LATTER PORTIONS OF THIS
WEEK...WITH THIS ENHANCED FLOW LIFTING NEWD THEREAFTER. THIS FLOW
WILL OVERLIE DRY SFC CONDITIONS TO ENHANCE THE FIRE WEATHER THREAT
ACROSS PORTIONS OF THE CNTRL GREAT BASIN AND SW STATES EWD TO THE
CNTRL/SRN HIGH PLAINS FOR D3/WED AND D4/THU. THEREAFTER...SOME
POTENTIAL FOR MODESTLY ENHANCED FIRE WEATHER CONDITIONS CANNOT BE
RULED OUT ACROSS PORTIONS OF THESE AREAS ON D5/FRI INTO THIS WEEKEND
AND PERHAPS INTO D8/MON. HOWEVER...DIFFERENCES AMONGST MODEL
SOLUTIONS REGARDING THE STRENGTH OF LOW/MID-LEVEL FLOW -- ALBEIT
LIKELY WEAK IN STRENGTH PER A LARGE PROPORTION OF MODEL GUIDANCE --
RENDER NO INCLUSION OF PROBABILISTIC DELINEATIONS AT THIS TIME FROM
D5/FRI THROUGH D8/MON FOR STRONG WIND/LOW RH POTENTIAL.

...D3/WED-D4/THU: CNTRL GREAT BASIN AND SW STATES EWD TO THE
CNTRL/SRN HIGH PLAINS -- STRONG WIND/LOW RH POTENTIAL...
D3/WED: AS A ZONE OF ENHANCED DEEP-LAYER FLOW OVERLIES DRY/VERY DRY
SFC CONDITIONS AMIDST DRY/VERY DRY FUELS FROM NRN AZ AND NWRN NM NWD
INTO THE SERN HALF OF UT AND WRN CO...CRITICAL FIRE WEATHER
CONDITIONS ARE EXPECTED IN THESE AREAS. ACROSS THE CRITICAL
AREA...SSWLY TO SWLY SFC WINDS OF 20-25 MPH WITH HIGHER GUSTS ARE
EXPECTED TO ALIGN WITH RH VALUES FROM THE MIDDLE SINGLE DIGITS TO
THE MIDDLE TEENS. ELEVATED FIRE WEATHER CONDITIONS WILL ENCOMPASS A
BROADER REGION SURROUNDING THE CRITICAL AREA AS RH VALUES BECOME
CRITICALLY LOW...THOUGH CRITICALLY STRONG SUSTAINED WIND SPEEDS ARE
NOT EXPECTED TO OCCUR ON ANY MORE THAN A BRIEF/SPOTTY BASIS OUTSIDE
OF THE CRITICAL AREA IN THE ABSENCE OF STRONGER LOW/MID-LEVEL FLOW.
WHILE CRITICAL METEOROLOGICAL CONDITIONS MAY EXTEND NWD INTO PARTS
OF SRN WY...LIMITED AVAILABILITY OF DRY FUELS PREVENTS THE CRITICAL
AREA FROM EXTENDING FARTHER N INTO WY.

D4/THU: RH VALUES ARE EXPECTED TO BECOME CRITICALLY LOW IN MANY
AREAS. HOWEVER...CONFIDENCE IN CRITICALLY STRONG SUSTAINED WIND
SPEEDS OCCURRING ON ANY MORE THAN A LOCALIZED/SHORT-DURATION BASIS
IS LOW AS LOW/MID-LEVEL FLOW LIKELY WEAKENS. AN AREA OF
CONCERN...HOWEVER...IS ACROSS PORTIONS OF THE HIGH PLAINS FROM NERN
NM AND THE ADJACENT TX PANHANDLE NWD INTO SERN CO AND SWRN
KS...WHERE DOWNSLOPE FLOW MAY BE ASSOCIATED WITH HOT...VERY
DRY...AND POTENTIALLY STRONG WINDS. HOWEVER...CONFIDENCE IN ANY MORE
THAN SPOTTY/BRIEF INSTANCES OF CRITICALLY STRONG WINDS IS LIMITED
SUCH THAT A CRITICAL AREA IS NOT WARRANTED...WITHOUT HIGHER
CONFIDENCE IN STRONGER LOW/MID-LEVEL FLOW.

...D3/WED: COASTAL RANGES AND ADJACENT FOOTHILLS OF SRN CA FROM
SANTA BARBARA COUNTY TO NWRN LOS ANGELES COUNTY -- STRONG WIND/LOW
RH POTENTIAL...
A LOCALLY/MODESTLY TIGHT PRESSURE GRADIENT W OF A SFC TROUGH OVER
THE LOWER CO RIVER VALLEY IS EXPECTED TO SUPPORT NNWLY TO NNELY
WINDS OF 15 TO 20 MPH WITH LOCALLY HIGHER GUSTS...WITH THE STRONGEST
WINDS EXPECTED THROUGH FAVORED PASSES AND CANYONS. DOWNSLOPE EFFECTS
AMIDST A DRY AIR MASS WILL AID IN DRYING/HEATING OF THE BOUNDARY
LAYER...WITH MINIMUM RH VALUES FROM THE UPPER SINGLE DIGITS TO
MIDDLE TEENS EXPECTED. THESE FACTORS MAY SUPPORT ELEVATED FIRE
WEATHER CONDITIONS AMIDST DRY/VERY DRY FUELS. HOWEVER...IN THE
ABSENCE OF AN EVEN TIGHTER SFC PRESSURE GRADIENT...CRITICALLY STRONG
SUSTAINED WIND SPEEDS ARE NOT EXPECTED TO OCCUR ON ANY MORE THAN A
BRIEF/SPOTTY BASIS.

...D4/THU-D7/SUN: WRN TWO-THIRDS OF NM AND ERN AZ -- DRY
THUNDERSTORM POTENTIAL...
A MID-LEVEL RIDGE WILL GRADUALLY BUILD AND THEN PERSIST ACROSS PARTS
OF THE S-CNTRL CONUS LATE THIS WEEK INTO THIS WEEKEND. AN INCREASING
SLY FLOW COMPONENT W OF THE RIDGE AXIS WILL DRAW MODEST AMOUNTS OF
MID-LEVEL MOISTURE NWD. ASSOCIATED BUOYANCY AND OROGRAPHIC EFFECTS
MAY PROMOTE ISOLATED HIGH-BASED THUNDERSTORM DEVELOPMENT...WHICH MAY
CONTAIN LIMITED PRECIPITATION AMOUNTS OWING TO RELATIVELY LOW PW AND
DEEP SFC-BASED MIXED LAYERS SUPPORTING SUB-CLOUD EVAPORATION. SOME
RISK FOR DRY THUNDERSTORMS MAY EXIST. HOWEVER...DEEP-LAYER FORCING
FOR ASCENT MAY NOT BE STRONG ENOUGH TO SUPPORT ANY MORE THAN
ISOLATED DRY THUNDERSTORMS. FURTHERMORE...UNCERTAINTY REGARDING THE
SPATIAL DISTRIBUTION OF LOW/MID-LEVEL MOISTURE CONTENT EXTENDS TO
THE POTENTIAL PRECIPITATION AMOUNTS FROM STORMS AND THE POTENTIAL
FOR A DRY-THUNDERSTORM MODE. AS SUCH...PROBABILITIES ADDRESSING THE
DRY THUNDERSTORM POTENTIAL HAVE NOT BEEN INCLUDED AT THIS TIME.

..COHEN.. 06/17/2013

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