Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
581 FXUS66 KHNX 221132 AAA AFDHNX Area Forecast Discussion National Weather Service Hanford CA 1005 PM PDT Mon Apr 21 2025 .UPDATE... Updated Aviation section. && .KEY MESSAGES... 1. A slight chance (10%-20%) of high Sierra Nevada afternoon thunderstorms. 2. Warming trend in temperatures through Tuesday. 3. Temperatures will see a cooling trend starting mid-week ahead of a disturbance moving into the area next weekend. 4. Locally breezy conditions expected across the Mojave Desert from the middle of next week into next weekend. && .DISCUSSION... Another sunny day as a ridge of high pressure moves overhead. A high Probability of Exceedance (PoE) of reaching 85 degrees during the early part of the week and then tapers-off later in the week. PoE of 85 degrees or greater will range from 70%-90% through Tuesday and lower to less then 20% by Thursday. Current surface pressure gradient from KSFO to KLAS sits at around 3mb. This translates into light winds across the district. Until the disturbance enters the region, winds will remain light and diurnally driven. Cooling will begin on Wednesday as temperatures drop to a few degrees below seasonal normal values (around 75 degrees) by Friday and Saturday. Longer range upper-air ensemble analysis is leaning toward the introduction of a trough pattern near the weekend. While widespread precipitation is very unlikely across Central California, decreasing temperatures and increasing winds have a higher probability of occurring. Longer range temperatures PoE analysis is showing a 50% chance of temperatures reaching 75 degrees on Saturday. With PoE of seeing even lower temperatures, confidence is high of a good cool-down by next weekend. At the same time, PoE for wind gusts will increase as percentages rise to 40%-60% during the Friday and Saturday time frame. At the moment, Sunday will see little change in temperatures and winds before a transition back to warming closer to Day-8 (Monday). && .AVIATION...12Z: Mountain thunderstorms along the crests of the Sierra Nevada are possible this afternoon between 18Z and 00Z. Otherwise, VFR conditions will prevail across the central CA interior thru 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... None. && $$ Public/Aviation....Molina/BSO weather.gov/hanford