Area Forecast Discussion
Issued by NWS Sacramento, CA
Issued by NWS Sacramento, CA
353 FXUS66 KSTO 140951 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 251 AM PDT Fri Jun 14 2024 .SYNOPSIS... Critical fire weather conditions likely Saturday night through Monday afternoon across the Sacramento Valley due to gusty northerly winds and low relative humidity. Seasonable temperatures and dry conditions continue over the next several days. && .DISCUSSION... Key Points - A Fire Weather Watch remains in effect from 11 PM Saturday - 5 PM Monday across the majority of the Sacramento Valley due to low daytime relative humidity, gusty northerly winds, and poor overnight recoveries. - Northerly winds may continue early next week maintaining some locally elevated fire weather conditions Tuesday - Seasonable temperatures the next several days, then gradually warming mid to late next week Short-Term Discussion (Today THROUGH Monday)... Current GOES-West satellite imagery shows mostly clear skies across interior northern California early on this Friday morning. Temperatures are currently trending approximately around 2 to 8 degrees cooler than this time yesterday morning, valid at 230 AM PDT. Locally breezy onshore flow is being observed with the Delta Breeze in the Delta and adjacent Valley areas. Seasonable temperatures are in the forecast over the next several days, with mainly Minor HeatRisk. High temperatures are projected to be in the 80s to 90s in the Valley/Delta, 80s to around 90 in the foothills, and 60s to 80s in the mountains. Critical fire weather conditions develop in the Sacramento Valley over the weekend and continue into Monday due to gusty northerly winds and low relative humidity. The National Blend of Models (NBM) indicates a 25-50% probability of wind gusts of 40 mph or greater in the Sacramento Valley, strongest on Sunday. Minimum relative humidity is expected to be in the 10-20% range, with overnight recoveries of about 20-45%. This combination of low relative humidity and gusty northerly winds has warranted a Fire Weather Watch that remains in effect from Saturday night through Monday afternoon to address the increasing confidence for these conditions. && .EXTENDED DISCUSSION (Tuesday THROUGH Friday)... Ensembles and clusters show upper level low gradually weakening over the Great Basin Region through next week. This will keep lingering breezy winds over NorCal through Wednesday. Temperatures gradually warm up next week into the 90`s, but uncertainty in just how much remains uncertain with a progressively widening ensemble spreads by late week. && .AVIATION... VFR conditions over interior NorCal next 24 hours. Southerly surface winds up to 20 kts in the southern Sacramento Valley, and northwesterly wind gusts up to 20 kts northern San Joaquin Valley until 06Z Saturday. Surface winds 15-25 kts vicinity Delta with gusts up to 30 kts. && .STO WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Saturday evening through Monday afternoon for Central Sacramento Valley in Glenn, Colusa, Yuba, Northern Sutter, and Butte County Below 1000 Ft-Eastern Mendocino NF-Northern Sacramento Valley to Southern Tehama County Line Below 1000 Ft-Northern Sierra Foothills from 1000 to 3000 Ft. Includes portions of Shasta-Trinity and Butte Units- Northern Sierra Including Lassen NP and Plumas and Lassen NF/S West of the Sierra Crest (West of Evans Peak-Grizzly Peak- Beckworth Peak)-Southeast Edge Shasta-Trinity NF and Western Portions of Tehama-Glenn Unit-Southern Sacramento Valley in Yolo- Sacramento Far Western Placer, southern Sutter and Solano County Below 1000 Ft. && $$