Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
038 FXUS66 KHNX 030930 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 230 AM PDT Mon Jun 3 2024 KEY MESSAGES... 1. Gusty west winds will redevelop across the Mojave Desert Slopes this evening through early Monday morning. Winds will be stronger and more widespread across the Mojave Slopes on Monday afternoon through early Tuesday morning. 2. A significant warming trend will take place this week. An Excessive Heat Warning is in effect for the San Joaquin Valley and adjacent foothills, the Kern River Valley, and the Kern County Desert on Wednesday and Thursday. 3. Temperatures are forecast to lower slightly on Friday with more cooling over the weekend. Temperatures are forecast to still be a few degrees above normal by Sunday. 4. The anticipated heat later this week will lead to increased snowmelt over the Sierra Nevada. Colder and higher flows along rivers and waterways. && DISCUSSION... Zonal flow has developed aloft today, which will persist through Monday. Given the seasonal conditions, gusty winds are anticipated in parts of Kern County as we remain under a zonal pattern which is has been slightly disrupted by a minor shortwave. Currently areas of the Mojave Desert Slopes are seeing gusts just shy of 50mph; advisory level winds are expected to remain until 8AM PDT this morning. However, breezy conditions will continue throughout the morning and midday. Winds will once again reach advisory levels more broadly this afternoon and evening. Daytime temperatures will hover just around climatological norms today; with upper 80s to lower 90s expected in many locations. By Tuesday, the shallow trough and zonal flow will transition to a strengthening ridge, leading to our first significant heatwave of the year by Wednesday. Temperatures are expected to climb by 4-12 degrees from Monday to Tuesday, and then by an additional 9-16 degrees from Tuesday to Wednesday. Many locations in the San Joaquin Valley have a high probability of reaching 105 degrees or higher on both Wednesday and Thursday. Consequently, the Excessive Heat Watch has been upgraded to an Excessive Heat Warning, issued for the San Joaquin Valley and Kern County Desert from 11 AM PDT Wednesday through 8 PM PDT Thursday. The potential also exists that the Heat Warnings will extend into Friday. This heatwave poses a major heat risk, especially for individuals without access to adequate cooling and hydration. Above-average temperatures will persist from Friday through next Sunday. Fridays temperatures will be similar to Thursdays, with highs continuing to reach 105 degrees and above, along with warm overnight lows primarily in the 70s. Outside of the Kern County desert, the likelihood of temperatures reaching 105 degrees or higher on Friday is lower than on Thursday, ranging from 20-40% in the Central Valley. Probabilities of areas in the San Joaquin Valley seeing triple-digit temperatures persisting into the weekend range from 20-40%. The probability for 105 degrees or hotter remains about 40-70% for the Kern County desert on Friday, and 20-40% on Saturday. Although the ridge will shift and weaken, high temperatures near the century mark are expected to linger. Additionally, the high temperatures will accelerate snowmelt, leading to rapid and dangerous currents in streams and rivers, posing life-threatening risks. Please take precautionary measures if planning to enter the water and adhere to any lake and river closures. && 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 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... Wind Advisory until 7 AM PDT this morning for CAZ338. Excessive Heat Warning from 11 AM Wednesday to 8 PM PDT Thursday for CAZ300>317-319-321-332-337>339. && $$ MM/BSO weather.gov/hanford