Includes Yosemite National Park and Oakhurst
July 3, 2021 - The National Weather Service Hanford Office reports a few thunderstorms are possible in the Sierra Nevada this afternoon into this evening.In addition to dangerous cloud to ground lightning strikes, any thunderstorm could produce small hail, gusty and erratic winds, and intense rainfall rates, leading to localized flooding.
Area Forecast Discussion National Weather Service Hanford CA 416 AM PDT Sat Jul 3 2021 .SYNOPSIS... Isolated showers and thunderstorms will be possible over the Sierra Nevada each afternoon through Sunday. Otherwise dry and warm weather is expected, with temperatures running a few degrees above normal through the middle of next week. By late next week, temperatures will rise more sharply, increasing the risk of heat relate illnesses. && .DISCUSSION... Southerly flow between a high pressure ridge over the southwest US and a low pressure center offshore is steering a slug of moisture and weak instability northward across southern and central California. Satellite and radar indicate associated clouds and mainly light/elevated precipitation pushing north over the Kern County desert. As the moisture continues moving north during the day today, expect additional precipitation development, with showers and a few thunderstorms possible over the Sierra zones. Temperatures meanwhile will top out around 5 degrees above climo this afternoon. The ridge is progged to expand westward and strengthen during the next few days. Additional afternoon thunderstorm activity can be expect over the Sierra Sunday as moisture lingers, while temperatures remain around 5 degrees above normal. As the ridge further builds westward, moisture will decrease and the thunderstorm threat over the Sierra will diminish for the remainder of next week. The gradually building ridge will maintain above normal temperatures across central California through the middle of next week. For the latter part of next week, the ridge is progged to continue strengthening, with 500 mb heights nearing 600 decameters by Saturday. This anomalously strong high pressure center would lead to a significant heat event for our region with afternoon highs reaching around 8-12 degrees above normal. These conditions will create increased risks for heat related illnesses in the San Joaquin Valley, lower foothills and desert areas by the end of next week. && .AVIATION... MVFR/IFR conditions in and near showers and thunderstorms over the Sierra between 18z Sat and 02z Sun. VFR conditions will prevail elsewhere throughout Central California for the next 24 hours. && .AIR QUALITY ISSUES... On Saturday July 3 2021... Unhealthy for sensitive groups in Tulare County and Sequoia National Park and Forest. Further information is available at Valleyair.orgSource: NWS
