Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
949 FXUS66 KHNX 302234 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 334 PM PDT Thu Jul 30 2026 .UPDATE... Updated Aviation section, Key messages, Certainty. Added Heat Advisory info for SJ Valley and foothills. && KEY MESSAGES... 1. Major Heat Risk for the Indian Wells Valley, Mojave Slopes and Desert, with an Extreme Heat Warning in effect through next Monday. 2. Prolonged heat is expected to affect the SJ valley and adjacent foothills this weekend into early next week with a Heat Advisory in effect from Saturday afternoon through next Monday. 3. Seasonably dry conditions to prevail through the week, with slight increase in monsoonal moisture expected by early next week. Along with well above normal temperatures, this will produce elevated fire weather concerns into early next week. && DISCUSSION... A shortwave trough will progress through northern CA today allowing for very slight onshore pgrad from the Bay Area into the central valley with resultant NW winds 8-12 mph. However, no noticeable temperature effects will occur thanks to mid-upper level heights building as the ridge centered over NM gradually shifts westward. Highs today look on track with lower 100s expected in most location in the SJV and foothills to the 70s/80s in the mountains. Further east, and Extreme Heat Warning is in effect for the Desert region of Eastern Kern county with high temperatures expected to be near 110 F today. As the upper ridge continues to builds westward into the weekend, 850 temps will warm to between 28-34 C. As a result, high temperatures are expected to warm into the 104-108 F range in the SJV and 106-109 in the west side mountains and 110-115 in the Mojave Desert. In addition, low temperatures are expected to be in the 80s in the west side mountains and Deserts to he upper 60s-mid 70s in the SJV. Although dewpoints will remain in the 40s to lower 50s through Saturday, there is some indication in model guidance that a weak monsoon moisture plume will rotate around the upper ridge and support slightly higher humidities by Sunday/Monday. As a result, the Heat Risk is expected to be in the Moderate category likely rising into the Major Category for this weekend. The heatwave is expected to continue into early next week, although the duration of the hottest temperatures should not last more than 3-4 days as the upper ridge axis gets shunted back to the east associated with a stronger trough moving into the Pac NW/Northern Great Basin. Precip chances look near zero through the period, although an isolated TS can not be ruled out in the higher terrain late Sunday and Monday associated with the slight increase in monsoon moisture. Generally light winds will preclude serious fire concerns. However, seasonably dry vegetation combined with low RH readings will lead to continued heightened fire danger through the period. && AVIATION... VFR conditions will prevail for the next 24 hours. NW winds less than 10 kts will become light and variable overnight. Winds will increase again early tomorrow afternoon from the W-NW with speeds again expected to be less than 10 kts. Clear skies through the period. && AIR QUALITY ISSUES... Unhealthy for Sensitive Groups in eastern Tulare County and SJ valley portion of Kern County for today and Friday. && .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... Extreme Heat Warning until 11 PM PDT Monday for CAZ337>339. Heat Advisory from noon Saturday to 11 PM PDT Monday for CAZ301>317-319-321-332-334>336. && $$ public...Crosbie aviation....Crosbie weather.gov/hanford