Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
047 FXUS66 KHNX 042016 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 116 PM PDT Fri Oct 4 2024 .KEY MESSAGES... 1. Dry conditions and well above average temperatures will prevail through the middle of next week. There is a 35 to 65 percent chance of triple digit heat across much of the San Joaquin Valley this weekend. 2. A Heat Advisory remains in effect for the San Joaquin Valley, West Side Hills, and Sierra Foothills through 11 PM PDT Sunday. 3. Low afternoon humidity will occur across many locations along with poor to moderate overnight recoveries in the mountains and desert. 4. The Climate Prediction Center`s 6-10 and 8-14 day temperature outlooks show a 60 to 70 percent chance for above normal temperatures across the region. && .DISCUSSION...A large upper ridge which is currently centered over the Four Corners regions is maintaining an anonymously hot airmass across our area for the time being. Temperatures have cooled slightly today from Thursday when several all time record high temperatures for the month of October were shattered as a trough has pushed into the PAC NW and lowered heights a but as well as provided our area with some mid levels clouds pulled up from an offshore disturbance. Radar composites showed some sprinkles and light showers across our area earlier today that were embedded in this mid level moisture. The ridge is progged to strengthen some across central CA on Saturday with SREF showing rises in heights and thicknesses in addition to RH progs showing less in the way of mid level moisture. With triple digit heat still expected for much of the San Joaquin Valley, West Side Hills and Sierra Nevada Foothills today, and warming advertised for Saturday have decided to extend the Heat Advisory through the weekend until a cold front associated with the next upper trough is progged to push into our area on Monday and provide our area with a cooling trend on Monday and Tuesday. NBM probabilistic guidance is indicating a PoE of 100 DEG F in the San Joaquin Valley between 35 and 65 percent on Saturday and Sunday. By Monday, the PoE of 100 DEG F lowers to 10 percent or less across most of the San Joaquin Valley. NBM indicating the cooling trend will continue through the middle of next week as a weak trough moves through CA with daytime highs in the San Joaquin Valley lowering into the lower to mid 90s which is still well above normal, but below the level where there would be noticable heat impacts. Ensemble means are showing a stronger trough moving into CA by next Friday which will lower temperatures to near seasonal normals by the end of next week, but the cooling trend looks to be brief as the Climate Prediction Center`s 6-10 and 8-14 day temperature outlooks show a 60 to 70 percent chance for above normal temperatures across the region. && .AVIATION...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 high. 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... Heat Advisory until 11 PM PDT Sunday for CAZ300>322. && $$ public/aviation...DAS idss...JPK weather.gov/hanford