Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
078 FXUS66 KHNX 070810 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 110 AM PDT Fri Jun 7 2024 .KEY MESSAGES... 1. An Excessive Heat Warning remains in effect for the lower elevations through 8 PM today. 2. The Heat Risk will be major (red) today, which will impact anyone without effective cooling and/or adequate hydration. Impacts are likely in some health systems, heat-sensitive industries and infrastructure. 3. Temperatures will lower this weekend, but are forecast to still be around 3 to 6 degrees above normal by Sunday. 4. The anticipated heat could lead to increased snowmelt over the Sierra Nevada, resulting in colder and higher flows along rivers and waterways. 5. Another round of triple digit heat is forecast by the middle of next week, with probabilities of afternoon highs exceeding 100 degrees in the San Joaquin Valley between 40 and 60 percent. && .DISCUSSION...The large upper ridge that brought near records heat to much of our area on Thursday is now shifting eastward as a moisture deficient shortwave system moves across Norcal. This will result in a the beginning of a cooling trend across our area today with lowering heights and thicknesses with maximum temperatures expected to be 2 to 5 DEG F lower than Thursday`s near record highs. With this morning/s lows still expected to be well above normal, one more day of dangerous heat is anticipated for much of our area today and an Excessive Heat Warning remains in effect until 800 PM PDT as a result. SREF is showing an upper trough approaching CA on Saturday and moving into the state by Sunday which will bring further cooling to our area over the weekend with maximum temperatures in the San Joaquin Valley expected to be below the century mark by Saturday and only 3 to 6 DEG F above normal on Sunday. With this upper trough, breezy conditions in the usual wind-prone portions of our area such as the West Side Hills and the Mojave Desert Slopes are possible most noticably on Saturday afternoon and evening. An upper low is progged to break off of the weekend trough and cut off west of Baja by Monday then remain quasi-stationary through midweek then lift northeast across Socal late next week as another upper trough approaches the western CONUS. Medium range ensemble means are indicating heights rebounding on Monday and Tuesday which will bring about a warming trend across our area although temperatures are not expected to reach dangerous heat levels with the latest NBM probabilistic guidance indicating a 40 to 60 percent PoE of 100 DEG F in the San Joaquin Valley on Tuesday. Little change is anticipated for Wednesday then a cooling trend will taker place next Thursday and Friday as heights and thicknesses lower in response to the approaching trough although temperatures will remain slightly above daily climatological normals. && .AVIATION...VFR conditions will prevail across the Central CA interior for 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 high. 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... Excessive Heat Warning until 8 PM PDT this evening for CAZ300>317-319-321-332-337>339. && $$ public/aviation/fire wx...DAS idss...BSO weather.gov/hanford