Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0138 AM CDT Fri Aug 28 2020 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... ...Synopsis... Upper-level ridging over the Southwest and Rockies is forecast to weaken slightly under the influence of west coast troughing and increasing zonal flow over the Pacific Northwest. Warm and dry conditions are expected under the ridge of high pressure, where pockets of locally elevated fire weather potential will likely exist. To the east, widespread shower and thunderstorm activity associated with shortwave trough and the remnants of hurricane Laura will limit overall fire weather potential. ...southern/central Great Basin... The partial break down of the upper-level ridge associated with the southern edge of the passing shortwave trough will allow some stronger mid-level flow to return to portions of the Great Basin. Dry surface conditions are expected with RH near 10%, and elevated fire weather conditions will be possible where topographically enhanced winds overlap with the dry surface conditions. However, overall confidence in widespread elevated fire weather conditions is low, precluding any area highlights. ...California... Warm and dry conditions are expected across much of the central valley on the periphery of the ridge. While upper-level flow is forecast to remain relatively weak, locally elevated conditions are likely to occur adjacent to the higher terrain across the central and southern portions of the state. With receptive fuels and several ongoing large incidents, there remains some threat given locally elevated fire weather conditions. ...Dry Thunderstorms... Monsoonal moisture over the Southwest will support thunderstorm development this afternoon and evening. Model soundings show deep saturated profiles with precipitable water values exceeding 1 to 1.5 inches. The high water content and forecast slow storm speeds below 15 mph should favor predominately wet storms. Additional thunderstorms are possible, but less certain, across the Sierra and into portions of the northern Great Basin. Here, storms are likely to exist atop a drier boundary layer, with a mixed wet/dry mode. The lower water content, and presence of very receptive fuels, suggests these storms may pose some risk for dry lightning strikes. However, uncertainty in storm coverage is large enough to preclude the addition of a dry thunder area at this time. ..Lyons.. 08/28/2020 ...Please see www.spc.noaa.gov/fire for graphic product...Read more
from SPC Forecast Products http://www.spc.noaa.gov/products/fire_wx/fwdy1.html
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