177 FXUS66 KHNX 090458 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 958 PM PDT Tue Jul 8 2025 .UPDATE... Updated Aviation Section. && .KEY MESSAGES... 1. Temperatures near season averages across the region today before a gradual warm up into the triple digits later this week. 2. Low RH values 15 to 25 percent will stretch across much of the San Joaquin Valley and Sierra Nevada with values 5 to 10 percent in the Mojave Desert. RH will decrease over the region later in the week with warming temperatures. && .DISCUSSION... High pressure ridge pattern becoming the dominate feature over the West Coast during the latter half the week. With this, will expect a continuation of the warming trend as widespread triple digits will be seen by Thursday and Friday. In addition to the rise in temperatures, the ridge pattern will allow for monsoonal moisture to surge northward as a potential for convection will exist across the Mojave Desert later this week. With little change in the overall pattern, will expect the duration of the heat wave to last from near Friday through at least next Tuesday. Ensemble Probability of Exceedance (PoE) of reaching 100 degrees starts off below 30% over the next few days. Thursday marks the transition period at which time the PoE jumps up to a range between 50% and 90%, with the higher end on the west side of the San Joaquin Valley along the Interstate-5 corridor. Also, by Thursday, the Kern Desert maxs out its PoE with values above 90% for the duration of the period. Friday shows both the San Joaquin Valley and Kern Desert having probabilities in the 90% and above range. At that point, confidence in widespread triple digits increases for the start of the next heat wave. Little change in PoE values observed through the weekend as triple digits will be here to stay through the early part of next week. Ensemble Cluster analysis of Precipitable-Water is showing good consensus in attempting to push monsoonal moisture northward toward Central California later this week. While the southwesterly flow aloft will hinder its surge toward Central California. Yet, ensemble analysis does show a very slight chance of development toward Friday and Saturday across the Kern Desert. Otherwise, dry and hot across Central California with afternoon wind breezes over the favored locations. && .AVIATION... 06Z Update: VFR conditions will prevail for the next 24 hours across the Central California Interior. && .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/EW weather.gov/hanford weather.gov/hanford