ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 181650
DAY 1 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1150 AM CDT MON AUG 18 2014
VALID 181700Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR NWRN CA AND SWRN OREGON...
HAVE MADE MINOR ADJUSTMENTS TO THE SCATTERED DRY THUNDERSTORM AREA.
EVEN THOUGH A FEW STORMS MAY PRODUCE LOCAL WETTING RAINS...MANY
AREAS OUTSIDE THE STRONGEST STORM CORES ARE LIKELY TO REMAIN
RELATIVELY DRY AND A LARGE NUMBER OF LIGHTNING STRIKES ARE EXPECTED
TODAY IN FAR SWRN OREGON INTO NWRN CA WHERE FUELS ARE VERY DRY.
...PORTIONS NRN CA AND SWRN OREGON...
MORNING MODEL GUIDANCE CONTINUES TO HIGHLIGHT THE EXTREME SWRN
OREGON AND NWRN CA AREAS AS THE MOST LIKELY AREA FOR THUNDERSTORMS
TODAY WITH NUMEROUS LIGHTNING STRIKES. IN A COORDINATION CALL WITH
NRN CA GEOGRAPHIC COORDINATION CENTER/WFOS AND IMETS...AND FROM
REPORTS FROM YESTERDAY...IT CERTAINLY APPEARS LIKELY THAT SOME SMALL
AREAS NEAR THE STORM CORES CAN RECEIVE SIGNIFICANT WETTING RAINS
WHILE JUST A FEW MILES AWAY...NO WETTING RAINS ARE RECEIVED.
THUS...WITH THE VERY DRY FUELS STILL IN MANY AREAS OF NWRN CA AND
DRY FUELS IN SWRN OREGON...SCATTERED DRY THUNDERSTORMS WITH
STRONG/GUSTY AND ERRATIC OUTFLOW WINDS ARE EXPECTED DURING THE
AFTERNOON...INTO THE EVENING HOURS.
AREAS CLOSER TO THE COAST WHERE THE PRECIPITABLE WATER IS HIGHER
SHOULD HAVE THE BETTER CHANCE FOR WETTING RAINS WHILE INLAND...
HIGHER ELEVATION AREAS WILL BE MOST PRONE TO DRY THUNDERSTORMS. THE
AREAS SURROUNDING THE SCATTERED DRY THUNDERSTORM AREA WILL HAVE A
LESSER CHANCE OF DRY STORMS AND/OR FUELS ARE NOT AS DRY SO HAVE
CONTINUED THE ISOLATED DRY THUNDERSTORM AREA.
...PORTIONS OF CNTRL NV -- STRONG WIND/LOW RH POTENTIAL...
NO CHANGE.
..BOTHWELL.. 08/18/2014
.PREV DISCUSSION... /ISSUED 0218 AM CDT MON AUG 18 2014/
...SYNOPSIS...
EARLY-MORNING WATER VAPOR IMAGERY INDICATES A PAIR OF MID-LEVEL
IMPULSES ALONG THE PACIFIC NW COAST...WHICH ARE FORECAST TO
CONSOLIDATE INTO A CYCLONE THAT WILL ADVANCE SSWWD NEAR/JUST OFF THE
COAST. TO THE E...A MID-LEVEL RIDGE WILL EXTEND ACROSS PORTIONS OF
THE SRN ROCKIES/S-CNTRL CONUS...WHILE A SHORTWAVE TROUGH ADVANCES
FROM THE NRN PLAINS TO THE WRN GREAT LAKES REGION.
...PORTIONS OF NRN CA...SRN ORE -- DRY-THUNDERSTORM POTENTIAL...
ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO FORM ON THE
ERN/NRN PERIPHERY OF THE AFOREMENTIONED CYCLONE...WHERE ADEQUATE
MID-LEVEL MOISTURE WILL EXIST IN COMBINATION WITH DIURNALLY ENHANCED
BUOYANCY. THE GREATEST COVERAGE OF STORMS -- I.E. SCATTERED -- IS
EXPECTED FROM THE COASTAL RANGES OF NWRN CA AND EXTREME SWRN ORE TO
THE SISKIYOU MOUNTAINS WHERE TERRAIN-ENHANCED ASCENT OCCURS. THIS IS
WHERE A CRITICAL AREA FOR DRY THUNDERSTORMS IS IN EFFECT. PW VALUES
AND BOUNDARY-LAYER MEAN RH ARE GENERALLY EXPECTED TO BE SUFFICIENTLY
LOW TO LIMIT PRECIPITATION AMOUNTS WITH THESE STORMS...WARRANTING
MAINTENANCE OF THE CRITICAL AREA. WHILE PW VALUES IN CLOSER
PROXIMITY TO THE COAST /0.75-1.00 INCH/ WILL BE HIGHER THAN THOSE
MORE OFTEN ASSOCIATED WITH STRICTLY DRY THUNDERSTORMS...VERY DRY
FUELS EXIST IN THESE AREAS WHICH WILL GREATLY ENHANCE THE RISK FOR
LIGHTNING-INDUCED IGNITIONS -- PARTICULARLY ON THE EDGES OF RAIN
CORES.
SURROUNDING THE CRITICAL AREA...AN ISOLATED DRY-THUNDERSTORM AREA
REMAINS IN EFFECT...WHERE EITHER /1/ RELATIVELY HIGHER PW INCREASES
THE CHANCES FOR WETTING RAINS AND MIXED WET/DRY-THUNDERSTORM
MODES...AND/OR /2/ WEAKER ASCENT IN AREAS OF DRIER TROPOSPHERIC
PROFILES FAVORS LOWER DRY-THUNDERSTORM COVERAGE. IN EITHER
CASE...THE COVERAGE OF PURELY DRY THUNDERSTORMS IS EXPECTED TO BE
TOO LIMITED FOR CRITICAL DESIGNATION.
...PORTIONS OF CNTRL NV -- STRONG WIND/LOW RH POTENTIAL...
MODESTLY ENHANCED MID-LEVEL SWLYS TO THE E OF THE AFOREMENTIONED
CYCLONE WILL OVERLIE THE REGION DURING PEAK HEATING WHEN RH VALUES
FALL TO 10-20 PERCENT. DEEP VERTICAL MIXING INTO THIS ENHANCED FLOW
ALOFT MAY SUPPORT SSWLY/SWLY SFC WINDS OF 15-20 MPH WITH LOCALLY
HIGHER GUSTS. LOCALLY/MARGINALLY ELEVATED FIRE WEATHER CONDITIONS
CANNOT BE RULED OUT. HOWEVER...ABOVE-NORMAL PRECIPITATION DURING THE
PAST COUPLE OF WEEKS IN MANY AREAS IS EXPECTED TO LIMIT THE
FIRE-WEATHER RISK SUFFICIENTLY SUCH THAT FIRE-WEATHER HIGHLIGHTS ARE
NOT WARRANTED AT THIS TIME.
...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 181851
DAY 2 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0151 PM CDT MON AUG 18 2014
VALID 191200Z - 201200Z
AN ISOLATED DRY THUNDERSTORM AREA HAS BEEN INTRODUCED FOR PORTIONS
OF NORTHERN CA AS UPPER TROUGH BECOMES BETTER ESTABLISHED OVER THE
PACIFIC NW.
...PORTIONS OF NORTHERN CALIFORNIA...
ALTHOUGH A MIXED MODE OF WET AND DRY STORMS IS EXPECTED....A FEW DRY
STORMS ARE POSSIBLE EVEN THOUGH THEY SHOULD BE TRANSITIONING TO MORE
WET STORMS. WITH NRN CA NEAR THE BASE OF THE UPPER TROUGH AND
MARGINAL INSTABILITY ACROSS THE AREA...A FEW STORMS ACROSS NRN CA
MAY STILL PRODUCE LITTLE IN THE WAY OF WETTING RAINS. PW STILL
REMAINS ABOUT 0.75 TO 1.0 INCH AND MOST PORTIONS OF NRN CA REMAIN
EXTREMELY DRY. TO THE NORTH AND EAST IN SERN OREGON AND NWRN
NV...FUELS ARE NOT AS DRY AND A FEW DRY STORMS ARE ALSO POSSIBLE.
...PORTIONS OF ERN/CNTRL ORE...ERN/CNTRL WA -- STRONG WIND/LOW RH
POTENTIAL...
NO CHANGE TO THIS ELEVATED FIRE WEATHER AREA.
..BOTHWELL.. 08/18/2014
.PREV DISCUSSION... /ISSUED 0218 AM CDT MON AUG 18 2014/
...SYNOPSIS...
A MID-LEVEL CYCLONE IS FORECAST TO ADVANCE SLOWLY SWD NEAR/JUST OFF
THE CA COAST...WHILE A TROUGH TO ITS N DIGS INTO THE NWRN CONUS.
DOWNSTREAM...MID-LEVEL RIDGING WILL OCCUR ACROSS THE N-CNTRL
STATES...WHILE CYCLONIC FLOW COVERS THE GREAT LAKES REGION.
...PORTIONS OF ERN/CNTRL ORE...ERN/CNTRL WA -- STRONG WIND/LOW RH
POTENTIAL...
MODESTLY ENHANCED TROPOSPHERIC FLOW ASSOCIATED WITH THE
AFOREMENTIONED DIGGING TROUGH IS FORECAST TO SUPPORT WLY TO NWLY SFC
WINDS OF 15 TO LOCALLY AROUND 20 MPH AND OCCASIONALLY HIGHER GUSTS.
WITH AFTERNOON RH EXPECTED TO BE IN THE 20S...ELEVATED FIRE WEATHER
CONDITIONS MAY OCCUR. HOWEVER...THE ABSENCE OF STRONGER
LOW/MID-LEVEL FLOW IS EXPECTED TO KEEP ANY INSTANCES OF CRITICALLY
STRONG WINDS MARGINAL...BRIEF...AND SPOTTY.
...PORTIONS OF NRN CA...SRN ORE...NWRN NV -- DRY-THUNDERSTORM
POTENTIAL...
LINGERING MID-LEVEL MOISTURE AND DIURNALLY ENHANCED
BUOYANCY/OROGRAPHIC CIRCULATIONS WILL SUPPORT ISOLATED THUNDERSTORMS
DURING THE AFTERNOON. WHILE PW VALUES AROUND 0.5-0.8 INCH MAY YIELD
LIMITED PRECIPITATION AMOUNTS...WEAK FLOW THROUGH THE TROPOSPHERE
WILL ENHANCE THE POTENTIAL FOR WETTING RAINS AS STORMS MOVE SLOWLY.
WHILE AN ISOLATED DRY-THUNDERSTORM RISK CANNOT BE ENTIRELY RULED
OUT...THE POTENTIAL IS CURRENTLY TOO LIMITED FOR FIRE-WEATHER
HIGHLIGHTS.
...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...
