Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
638 FXUS66 KHNX 180919 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 219 AM PDT Sun Aug 18 2024 && .KEY MESSAGES... 1. Confidence remains high for temperatures to be slightly below normal today, with a return to around normal temperatures early into the work week before a spell of below normal temperatures with highs 6 to 9 degrees below normal. Chances for above normal temperatures increase next week. 2. Despite increased relative humidity values, the risk of grass fires continues with breezy afternoon winds. The risk is highest in eastern Kern County due to elevated winds and relative humidity less than 10 percent. && .DISCUSSION... A trough right of the west coast of the CONUS will keep temperatures slightly below normal today. This trough along with the ridge over the southern central CONUS will continue to draw up dry air into the state. As the trough weakens into the beginning of the work week, the ridge will deepen slightly and the western side is expected to spread into Central California. This will lead to increased 500mb heights and temperatures in most of the region approaching around normal, with the desert areas seeing above normal temperatures. This is expected to last until Wednesday. By Thursday, another trough is expected to dive down from the Canadian coast and cause a lowering of temperatures again, with highs expected to be 6-9 degrees below normal on Friday. Probabilities also show this, with chances for 90 degrees or lower in the valley on Friday at 50-80%. Relative humidities in the desert region will continue to be 10 percent or less through this week and winds will continue to be breezy in the afternoon. These factors combined with very dry fuels will continue the risk for small grass fires. By next weekend, relative humidities will increase slightly in the desert to the low teens on Friday, at the same time as the lowered temperatures due to the trough coming in on Thursday. Long term models are showing the trough will leave the area by Saturday and a ridge will build into the area as next week progresses, which will lead to a gradual warm up for the region and we may see the return of triple digits. Probabilities for 100 degrees or higher in the valley for next Tuesday are 65-75%. && .AVIATION... Areas of MVFR and local IFR visibilities will continue in and around wildfires. Otherwise, VFR conditions will prevail across the central CA interior over the next 24 hours. && .AIR QUALITY ISSUES... None. && .CERTAINTY... The level of certainty for days 1 and 2 is medium. The level of certainty for days 3 through 7 is medium. Certainty levels include low...medium...and high. Please visit www.weather.gov/hnx/certainty.html for additional information and/or to provide feedback. && .HNX WATCHES/WARNINGS/ADVISORIES... None. && $$ Public/Aviation/Fire Weather.........EW DSS/PIO..............................DCH weather.gov/hanford