Storm Prediction Center Day 1 Fire Weather Outlook
Created: Sat Dec 16 16:10:02 UTC 2017 ( | )
Click for Day 1 FireWX Areal Outline Product
ZCZC SPCFWDDY1 ALL FNUS21 KWNS 161608 Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1008 AM CST Sat Dec 16 2017 Valid 161700Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND NORTHERN CALIFORNIA... The ongoing forecast is on track with no changes needed. Several areas of gusty northerly/northeasterly flow will persist across portions of California today amidst very low RH values, resulting in potential for rapid fire spread. Farther east in the Plains, elevated fire weather conditions will develop for a few hours in the afternoon with RH values falling to around 15-20% within the elevated area. Locally elevated fire weather conditions can also be expected in northeastern Oklahoma and vicinity, where 10-20 mph southerly winds will briefly combine with minimum RH values of around 25-30%. See the previous forecast below for more detail. ..Cook.. 12/16/2017 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Dec 16 2017/ ...Synopsis... Strong northerly deep-layer flow on the back side of an amplifying upper trough over the Great Basin will overspread much of CA today. At the same time, surface high pressure will build over the Pacific Northwest today, and into the Great Basin tonight. This will result in an increasing surface pressure gradient first over northern CA. As stronger high pressure slides southward into the Great Basin this evening, offshore gradients will increase over southern CA. The net result will be a large area of elevated to critical fire weather conditions across much of California today and tonight. Increasing southerly deep-layer flow will overspread the southern Plains today as a shortwave trough lifts northeast from northern Mexico into TX by this evening. At the surface, a lee low will develop over the central/southern High Plains and an increasing pressure gradient across the region will aid in development of gusty surface winds and elevated fire weather conditions will be possible. ...Portions of Central into Northern CA Today and Tonight... Gusty north winds were already occurring as of 07z across portions of the Bay Area mountains and foothills. RH values are expected to fall critically low later this morning and elevated to critical conditions are expected to persist through the remainder of the period across portions of central into northern CA. Critical conditions are most likely in the mountains and foothills near the Bay Area southward along the Diablo and Santa Cruz Mountain Ranges into adjacent portions of the Sacramento Valley. RH values will fall into the 10-20 percent range during the day with north winds around 15-30 mph with higher gusts possible. ...Portions of Southern CA... Gusty winds were already occurring as of 07z across parts of the Santa Barbara County mountains in conjunction with very low RH. Critical conditions will continue through this evening as north to northeast winds of 15-25 mph with stronger gusts persist. Further south and east toward Ventura, Los Angeles, Orange and western San Bernardino and Riverside Counties, gusty northeasterly winds will return Saturday night into Sunday morning. Expect sustained winds of 20-30 mph with higher gusts. RH values will fall into the 15-25 percent range Saturday night, before falling further during the day on Sunday. ...Portions of the Central and Southern High Plains... Breezy and dry conditions are expected across portions of the central and southern High Plains today. As temperatures warm into the 50s to low 60s, boundary-layer mixing to around 2-3kft will ensue, resulting in further drying and downward transport of stronger midlevel winds. RH values of 20-30 percent will be widespread with sustained winds around 15-20 mph and higher gusts. ...Please see www.spc.noaa.gov/fire for graphic product...
Fire Weather/Forecast Products/Home