DAY 2 FIRE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1059 AM CST THU NOV 12 2015 VALID 131200Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN CA COASTAL RANGES AND ADJACENT FOOTHILLS... NO CHANGES TO THE PREVIOUS FORECAST ARE NEEDED. SEE DISCUSSION BELOW FOR MORE DETAILS. ..LEITMAN.. 11/12/2015 .PREV DISCUSSION... /ISSUED 0234 AM CST THU NOV 12 2015/ ...SYNOPSIS... IN THE MID LEVELS...A SHORTWAVE TROUGH WILL MOVE ACROSS PARTS OF THE GREAT LAKES REGION AND NERN CONUS...WITH AN UPSTREAM RIDGE MOVING ACROSS PARTS OF THE N-CNTRL CONUS. FARTHER W...A BELT OF STRONG WLY FLOW WILL GRADUALLY SHIFT SWD ACROSS PARTS OF THE NWRN CONUS THROUGH THE PERIOD. AT THE SFC...AN ANTICYCLONE WILL BE SITUATED ACROSS PARTS OF THE CNTRL GREAT BASIN...AND IS FORECAST TO GRADUALLY BE WEAKENING BY LATE IN THE D2/FRI PERIOD. ...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 CONTINUE INTO D2/FRI. THIS IS FORECAST TO SUPPORT NELY TO ELY WINDS AROUND 20-25 MPH -- LOCALLY STRONGER AND WITH HIGHER GUSTS IN TERRAIN-FAVORED AREAS INCLUDING LOCATIONS THROUGH CANYONS AND PASSES. ALSO...AFTER POOR RH RECOVERY THURSDAY NIGHT...DRY CONDITIONS WILL BE IN PLACE ON D2/FRI. THE COMBINATION OF THE PREVIOUSLY MENTIONED WINDS...AND MINIMUM RH AROUND 7-15 PERCENT...IS EXPECTED TO YIELD CRITICAL FIRE-WEATHER CONDITIONS. THIS SHOULD PARTICULARLY BE THE CASE EARLY IN THE PERIOD. BY LATE IN THE D2/FRI PERIOD...SFC WINDS ARE EXPECTED TO BE WEAKENING AS THE ANTICYCLONE WEAKENS...CORRESPONDING TO A LESSENING OF THE OVERALL FIRE-WEATHER RISK. HOWEVER...DRY CONDITIONS WILL LINGER INTO THE OVERNIGHT HOURS OF FRIDAY NIGHT WITH POOR OVERNIGHT RH RECOVERY EXPECTED. FOR THE ELEVATED FIRE-WEATHER AREA THAT SURROUNDS THE CRITICAL AREA...A RELATIVELY TIGHT SFC PRESSURE GRADIENT IS EXPECTED TO CONTINUE SUPPORTING ENHANCED WINDS INTO THE D2/FRI PERIOD. HOWEVER...SIMILAR TO D1/THU...THESE WINDS ARE NOT FORECAST TO BE 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. LOCALLY/BRIEFLY CRITICAL CONDITIONS CANNOT BE RULED OUT...ESPECIALLY EARLY IN THE PERIOD. HOWEVER...CONFIDENCE IN CRITICALLY STRONG WINDS OCCURRING ON MORE THAN A LOCALIZED/SHORT-DURATION BASIS IS NOT HIGH ENOUGH FOR CRITICAL DESIGNATION AT THIS TIME. WINDS ARE EXPECTED TO BE WEAKENING BY LATE D2/FRI AS THE SFC PRESSURE GRADIENT WEAKENS...RESULTING IN A LESSENING OF THE FIRE-WEATHER RISK. ALSO...SOME AREAS OF LESS-RECEPTIVE FUELS FOR FIRE SPREAD TO THE S OF THE CRITICAL AREA MAY MITIGATE THE OVERALL FIRE-WEATHER POTENTIAL. ...PLEASE SEE http://ift.tt/KCM4Ij FOR GRAPHIC PRODUCT...Read more
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