Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
595 FXUS66 KHNX 102119 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 219 PM PDT Mon Jun 10 2024 .KEY MESSAGES... 1. Isolated strong thunderstorms are possible this afternoon and early evening along the Sierra Nevada crest from Yosemite NP to Kings Canyon NP. 2. Temperatures warm trend warmer to around 10 to 15 degrees above climatological averages on Tuesday and Wednesday. 3. A Heat Advisory is in effect for Tuesday and Wednesday, with probabilities of afternoon highs exceeding 100 degrees in the San Joaqin Valley around 65-90%. The probability of exceeding 105 degrees is less than 20% with the exception of Fresno and Visalia being about 30 to 45%. 4. The warm temperatures will allow increased snowmelt to continue over the Sierra Nevada, resulting in colder and higher flows along rivers and waterways. && .DISCUSSION... Satellite loops show sunny skies prevailing across the central California interior early this afternoon. Upper ridging over the eastern Pacific is merging with ridging over the southwest while a weak upper low spins off the coast of northern Baja California. 24hr trends show temperatures around 2 to 4 degrees warmer with highs forecast to top out around 4 to 7 degrees above average this afternoon. Afternoon convection over the Sierra Nevada will lead to some cumulus development with a slight chance for a few strong thunderstorms this afternoon and early evening. The ridge strengthens on Tuesday resulting in further warming. Much of the lower elevations will climb into the triple digits with highs near 10 to 15 degrees above climatological averages. A Heat Advisory is in effect for the San Joaquin Valley, the lower Sierra Nevada foothills, the West Side Mountains, and the Kern River Valley from 11 AM Tuesday through 6 AM PDT Thursday. Here are probabilities for a high temperature of 102 degrees or higher for some locations across the San Joaquin Valley. Tue Wed Merced 46% 56% Madera 46% 56% Fresno 71% 71% Reedley 46% 56% Lemoore 51% 56% Hanford 56% 56% Visalia 71% 66% Porterville 51% 56% Delano 51% 51% Bakersfield 51% 66% The ridge breaks down on Thursday as the upper low moves inland over southern California. A Gulf of Alaska low then moves across the Pacific Northwest this weekend with broad troughing over the western CONUS. Temperatures drop back to around 4 to 7 degrees above average on Thursday and then fall to near average for the weekend. Winds will be on the increase later in the week after the ridge breaks down. Strong wind gusts are expected across the Mojave Desert slopes Friday and through the weekend with breezy conditions elsewhere. && .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... Heat Advisory from 11 AM Tuesday to 6 AM PDT Thursday for CAZ300>317-319-332. && $$ DCH weather.gov/hanford