SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0203 PM CDT Mon Oct 26 2020 Valid 271200Z - 281200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN INTO CENTRAL CALIFORNIA... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... Much of the previous forecast remains on track. Latest model guidance consensus depicts 15-25 mph sustained northerly surface winds amidst 10-20% RH across portions of the Sacramento and upper San Joaquin Valley areas Tuesday afternoon, necessitating the maintenance of a Critical area given exceptionally dry fuels in place. Offshore flow and widespread 10-20% RH will continue all day Tuesday across the southern Transverse Ranges in southern California. The strongest winds (i.e. widespread 25+ mph with higher gusts) are expected to occur mainly during the morning, with gradual weakening expected through the afternoon into the overnight hours as upper support continues to move away from California. The Elevated area across the Lower Colorado River Basin was expanded farther north into far southern Nevada. Temperatures are forecast to warm into the 50s, with widespread 15-25 mph sustained northerly surface winds coinciding with critically low RH by afternoon peak heating. While surface temperatures will remain cool overall, the aforementioned favorable surface winds/RH overspreading very dry fuels will compensate to support an Elevated wildfire-spread threat. ..Squitieri.. 10/26/2020 .PREV DISCUSSION... /ISSUED 0216 AM CDT Mon Oct 26 2020/ ...Synopsis... Elevated to critical fire-weather conditions will continue across California and the Desert Southwest on D2/Tuesday as a persistently strong surface pressure gradient resides in these areas. There are indications that this gradient will weaken midday as high pressure over Nevada weakens slightly. However, models also indicate a restrengthening of the gradient in the latter half of the forecast period, which should maintain areas of gusty northerly/northeasterly surface winds and very low RH. ...Northern California and the Bay Area... Given the continued favorable pattern for fire weather, it is likely that elevated to critical fire-weather conditions (20-30 mph northerly flow and 5-20% RH values) will be ongoing early in the forecast period. Winds will slacken only briefly in a few areas during the day as temporary weakening of the surface pressure gradient occurs. This gradient will reintensify, however, with strong winds returning during the afternoon and continuing overnight. Fuels remain very dry in this region, and ERCs remain near record levels. Thus, an environment favorable for rapid fire spread will continue - especially in the critical delineation across the Sacramento Valley and eastern portions of the Bay Area. ...Coastal ranges of Southern California... The favorable offshore flow pattern will persist throughout the day across the region, and although slightly weaker winds are expected compared to D1/Monday, gusts to 50 mph or higher cannot be completely ruled out in terrain-favored areas. Fuels remain dry, and RH values will also exhibit poor recovery overnight while falling again into the 5-15% range amid peak heating. Critical fire-weather conditions are expected to persist throughout the day and continue into the overnight hours. ...Please see www.spc.noaa.gov/fire for graphic product...
from SPC Fire Weather Outlooks https://bit.ly/3kzz4VO
Be First to Comment