DAY 1 FIRE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0947 AM CST THU NOV 12 2015 VALID 121700Z - 131200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN CA COASTAL RANGES AND ADJACENT FOOTHILLS... NO CHANGE TO THE PREVIOUS FORECAST ARE NEEDED. SEE DISCUSSION BELOW FOR MORE DETAILS. ..LEITMAN.. 11/12/2015 .PREV DISCUSSION... /ISSUED 0233 AM CST THU NOV 12 2015/ ...SYNOPSIS... A DEEP CYCLONE WILL TRACK ACROSS PARTS OF THE GREAT LAKES REGION TO NEW ENGLAND...WITH BROADLY CYCLONIC MID-LEVEL FLOW BEING MAINTAINED UPSTREAM BY AN IMPULSE AMPLIFYING ACROSS PARTS OF THE NRN GREAT PLAINS AND THE UPPER MIDWEST. A FRONTAL SYSTEM ATTENDANT TO THE AFOREMENTIONED DEEP CYCLONE WILL BE ASSOCIATED WITH PRECIPITATION ACROSS PARTS OF THE ERN CONUS. FARTHER W...A RELATIVELY FLAT MID-LEVEL RIDGE OVER PARTS OF THE ERN PACIFIC WILL ADVANCE INTO PORTIONS OF THE WRN CONUS...WITH DOWNSTREAM SUBSIDENCE PROMOTING A SFC ANTICYCLONE ACROSS PARTS OF THE CNTRL GREAT BASIN. ...PORTIONS OF THE SRN CA COASTAL RANGES AND ADJACENT FOOTHILLS... ACROSS THE CRITICAL AREA...AN ENHANCED SFC PRESSURE GRADIENT ON THE SWRN FLANK OF THE AFOREMENTIONED ANTICYCLONE IS EXPECTED TO FOSTER NELY TO ELY WINDS AROUND 20-25 MPH -- LOCALLY STRONGER AND WITH HIGHER GUSTS IN TERRAIN-FAVORED AREAS INCLUDING LOCATIONS THROUGH CANYONS AND PASSES. DOWNSLOPE-FLOW-ENHANCED WARMING/DRYING AMIDST DEEP DRY AIR IS FORECAST TO YIELD MINIMUM RH OF AROUND 7-15 PERCENT THIS AFTERNOON. THESE FACTORS...COMBINED WITH AREAS OF DRY FUELS...ARE EXPECTED TO SUPPORT THE CRITICAL FIRE-WEATHER RISK. CRITICAL FIRE-WEATHER CONDITIONS ARE EXPECTED TO CONTINUE INTO THE OVERNIGHT HOURS TONIGHT ACROSS PORTIONS OF THE CRITICAL AREA...WITH POOR RH RECOVERY ANTICIPATED OWING TO THE AFOREMENTIONED DOWNSLOPE FLOW ENCOURAGING DRY CONDITIONS. FOR THE ELEVATED FIRE-WEATHER AREA THAT SURROUNDS THE CRITICAL AREA...A RELATIVELY TIGHT SFC PRESSURE GRADIENT IS STILL EXPECTED TO SUPPORT ENHANCED WINDS -- THOUGH NOT AS STRONG AS THOSE ACROSS THE CRITICAL AREA. NELY TO ELY SFC WINDS AROUND 15-20 MPH ARE EXPECTED TO COMBINE WITH MINIMUM RH AROUND 7-15 PERCENT TO SUPPORT ELEVATED FIRE-WEATHER CONDITIONS. THESE CONDITIONS ARE EXPECTED TO CONTINUE INTO THE OVERNIGHT HOURS TONIGHT...WITH POOR RH RECOVERY EXPECTED. LOCALLY/BRIEFLY CRITICAL CONDITIONS WILL BE POSSIBLE THROUGH THE PERIOD. HOWEVER...CONFIDENCE IN CRITICALLY STRONG WINDS OCCURRING ON MORE THAN A SPOTTY/BRIEF BASIS IS NOT HIGH ENOUGH FOR CRITICAL DESIGNATION ACROSS THE ELEVATED AREA AT THIS TIME. ALSO...SOME AREAS OF LESS-RECEPTIVE FUELS FOR FIRE SPREAD S OF THE CRITICAL AREA COULD MITIGATE THE OVERALL FIRE-WEATHER POTENTIAL. ...PLEASE SEE http://ift.tt/KCM4Ij FOR GRAPHIC PRODUCT...Read more
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