Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
661 FXUS66 KHNX 250839 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 139 AM PDT Tue Jun 25 2024 && .KEY MESSAGES... 1. A Heat Advisory remains in effect through 11 AM this morning due to warm overnight low temperatures. 2. Above average temperatures will continue this week, with 100 degree heat persistent for many locations through Wednesday. 3. There is a 10 to 30 percent probability for thunderstorms Tuesday afternoon along the Sierra Nevada crest from Yosemite National Park to the border of Tulare and Kern Counties. 4. Winds pick up on Thursday with a 40 to 45 percent chance of wind gusts of 40 mph or higher at the Mojave Desert Slopes. && .DISCUSSION... With the very high temperatures the past few days and the advection of the moisture from the remnants of former Tropical Storm Alberto, we had a few showers and thunderstorms the past two days. These thunderstorms produced cloud-to-ground lightning resulting in a few fires being started yesterday. These thunderstorms produced little to none rain because of hot and dry conditions in the lower levels and tropical moisture in the middle and upper levels. Latest model ensembles show the ridge stays in place keeping temperatures hot again and the moisture is still being advected. This combination brings a 10 to 30 percent chance of thunderstorms over the Sierra Nevada today and a 5 percent chance of thunderstorms in the Valley. The heat will remain today in the San Joaquin Valley as the NBM probabilities have a 35 to 45 percent probability of high temperatures of at least 103 degrees today. However, the probabilities for Merced and Madera are 15 percent or less of a high temperature of at least 103 today. Temperatures cool off on Wednesday as the model ensembles are showing the ridge weakening and moving east. Winds pick up on Thursday with a trough sliding across the Pacific Northwest. Latest probabilities show a 40 to 45 percent probability of wind gusts of 40 mph over the Mojave Desert Slopes on Thursday. The wind speeds decrease on Friday and Saturday. Model ensembles are showing a second trough sliding across the Pacific Northwest on Sunday bringing stronger gusts again to the Mojave Desert Slopes. Temperatures will remain persistent through the weekend with a less than 15 percent probability of triple digits for the entire weekend. && .AVIATION... MVFR conditions possible around scattered showers along the crest and surrounding foothills of the Sierra Nevada from 18Z Tuesday through 6Z Wednesday. There is a very slight chance of thunderstorms in the San Joaquin Valley between 18Z Tuesday and 3Z Wednesday. Otherwise, VFR conditions will prevail across the central California 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... Heat Advisory until 11 AM PDT this morning for CAZ300>317-319- 321-332. && $$ JPK weather.gov/hanford