Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
573 FXUS66 KHNX 081948 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 1248 PM PDT Wed May 8 2024 .KEY MESSAGES... 1. The warming trend will continue through next Wednesday. 2. By next Wednesday afternoon, high temperatures throughout Central California will be around 10 to 14 degrees above normal for this time of year. 3. A few strong thunderstorms are possible in the Sierra Nevada Friday afternoon and each afternoon through Wednesday of next week. && .DISCUSSION... Central California is currently in a broadly cyclonic northerly flow between a sharp Northeast Pacific ridge and a trough extending westward from upper level low pressure centered near the northern Great Plains area. Temperatures are trending gradually upward in this pattern and afternoon highs today are on track to top out right around normal readings for this time of year. The upper low is progged to migrate westward Thursday and recenter near the Great Basin region by Friday. This brings a more pronounced northeasterly flow Thursday and a more notable uptick in temperatures, especially in the San Joaquin Valley. High temperatures Thursday afternoon are forecast to be around 4 to 8 degrees higher than today. Probabilities for maximum temperatures of at least 86 degrees in the San Joaquin Valley on Thursday are around 50 to 70 percent. Temperatures will trend upward a few more degrees on Friday, with probabilities generally around 40 to 60 percent for afternoon highs of at least 90 degrees in the San Joaquin Valley. In addition, the proximity of the upper low will lead to increased instability and 15 to 25 percent probabilities for thunderstorms over the Sierra Nevada during the afternoon and evening on Friday. Saturday and Sunday afternoons will see Sierra thunderstorm probabilities lower slightly to around 10 to 15 percent as the upper low swings eastward and there is brief weak ridging over central California. Temperatures will trend upward a few more degrees to around 10 degrees above normal. Probabilities are around 50 to 70 percent for high temperatures of at least 92 degrees in the San Joaquin Valley Sunday afternoon. By Monday and Tuesday, another weak upper low approaching the California coast will bring a pause in rising temperatures, with afternoon highs holding near 10 degrees above normal. Thunderstorm probabilities over the Sierra will return to around 15 to 25 percent for Monday and Tuesday afternoons. Rebuilding high pressure Wednesday will bump temperatures up a few more degrees, likely to be our warmest day so far this year. Probabilities are around 50 to 60 percent for afternoon highs of at least 94 degrees in the San Joaquin Valley on Wednesday. Sierra thunderstorm probabilities meanwhile drop back to around 10 to 15 percent. && .AVIATION... VFR conditions will prevail across Central California for at least 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... None. && $$ public/aviation...JEB PIO/IDSS..........AS weather.gov/hanford