Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
025 FXUS66 KHNX 032123 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 223 PM PDT Wed Jul 3 2024 .KEY MESSAGES... 1. Temperatures will climb to around 15 degrees above normal this afternoon. This is a dangerous and prolonged heat wave that will last several days with an Extreme Heat Risk. 2. An Excessive Heat Warning remains in effect through Thursday, July 11th at 8 AM, and may need to be extended further as the week progresses. 3. The risk of grass fires will continue with herbaceous fuel loading at or near 120% of normal. A long period of excessive heat, minimum relative humidities near 15% and poor overnight recoveries will add to the grass fire risk. && .DISCUSSION... A strong upper ridge over the Eastern Pacific is continuing to build inland today and temperatures are rising in response. 24 hour trends show temperatures around 4 to 7 degrees higher than this time yesterday. The latest probabilities for a high temperature of 110 degrees or above are generally from 40-60 percent today. Probabilities are similar tomorrow then lower to around 20-40 percent on Friday. The center of the ridge is forecast to move over California this weekend with a ~599 dm height at 500 mb. Probabilities for a high of 110 jump up to 60-80 percent this weekend. The ridge weakens slightly early next week over the Great Basin. Probabilities for 110 lower to around 25-50 percent but probabilities for 105 degrees or above are from 50-90 percent. Some record high temperatures are likely to be tied or broken beginning today. Overnight low temperatures will remain warm, especially in the larger urban areas, meaning there will be little to no relief from the heat at night. Extreme Heat Risk will become widespread tomorrow and continue through the weekend into the middle of next week. The Excessive Heat Warning is now in effect until 8 AM PDT Thursday, July 11. && .AVIATION... Continued areas of MVFR and local IFR visibility due to smoke at and around the Fresno County fires will continue in the Sierra Nevada and adjacent foothills. 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... Excessive Heat Warning until 8 AM PDT Thursday for CAZ300>322- 324-332-334-336>339. && $$ DCH weather.gov/hanford