San Jacinto Weather Pages (California) including current sensor readings, forecasts, weather news and features, links, weather history and climate information http://weathercurrents.com/sanjacinto/ 60 Copyright 2026 WeatherCurrents. All rights reserved. en-us webmaster@weathercurrents.com http://static.weathercurrents.com/images/WeatherCurrentsBug.gif http://weathercurrents.com High: N/A°F at N/A Low: N/A°F at N/A Wind: N/A Precipitation: N/A http://weathercurrents.com/sanjacinto/ http://weathercurrents.com/sanjacinto//NewsItemDisplay.do?Id=1689 Triple-digit heat has returned to the region Tuesday, prompting the National Weather Service to issue an Extreme Heat Warning for the coasts, valleys and low desert until 8 PM Wednesday, as well as a Heat Advisory until 8 PM Thursday. Thunderstorms previously forecasted to impact the mountains on Tuesday, along with southeasterly flow, helped produce a large thunderstorm over Agua Tibia Mountain and Palomar Mountain Tuesday afternoon. As the thunderstorm grew and rapidly intensified, rain began to spill over into Temecula to the north, as well as Anza to the east. This prompted the National Weather Service to briefly issue a Severe Thunderstorm Warning for Temecula and Murrieta, however the thunderstorm weakened significantly just north of Temecula Tuesday evening. Thunderstorms had also formed over the San Diego County mountains. In addition, a large grouping of thunderstorms off the coast of Ventura County managed to bring rain to Simi Valley, although these storms had weakened ... http://weathercurrents.com/sanjacinto//NewsItemDisplay.do?Id=1688 Tropical moisture from Hurricane Marie in the Pacific Ocean, coupled with an upper level trough from the Pacific Northwest, produced widespread rainfall and thunderstorms early this week across the region - in what was the first rains of the 2026-2027 water year across the majority of Southern California communities. Increasingly cloudy, muggy, downright tropical weather descended upon Southern California over this Labor Day weekend. Rainfall and embedded thunderstorm activity was more focused to the north on Sunday, with especially heavy rainfall across Los Angeles County (with numerous cities breaking daily rainfall records). Precipitation dropped off significantly south of Los Angeles and San Bernardino, with San Diego County seeing only scant rainfall on Sunday. By Monday morning, dense storm activity over LA County had shifted south, producing scattered thunderstorms further south over Orange and Riverside counties. This activity sent waves of mostly light-to-moderate precip ... http://weathercurrents.com/sanjacinto//NewsItemDisplay.do?Id=1687 A broad upper level trough positioned over the West Coast is bringing not only relief from a hot August, but also mid-level tropical moisture connected to Hurricane Marie in the Pacific and potential precipitation for the region this weekend. Hurricane Marie, currently positioned far to our south, is projected to travel west and well out to sea, with no direct impacts expected. However, mid-level tropical moisture associated with Hurricane Marie is forecast to interact with the large upper level trough over the West Coast this weekend. Computer forecast models are increasingly in agreement on rainfall chances across the region, although rainfall amounts still vary considerably. According to the National Weather Service, ensemble means are currently showing precipitation amounts between 0.2-0.3 inches across the valleys, with higher totals for the coastal slopes and mountains. Due to uncertainty regarding the exact placement of the large upper low, rainfall amounts from this syste ... http://weathercurrents.com/sanjacinto//NewsItemDisplay.do?Id=1686 The recent stretch of exceptionally hot days across Southern California, has been exacerbated by modest humidity and high dew points - a rather uncommon combination for the region. Widespread high temperatures in the upper 90s and 100s across the inland valleys since roughly August 19, were compounded with unusually high heat index readings (Heat Index being a calculation that translates air temperature readings into what the conditions currently "feel like" to humans). Inland, heat index values exceeding 110 degrees were observed nearly every afternoon over the past week - brought on by unusually warm SSTs (Sea Surface Temperatures) off the Southern California coast, which contributed to relatively high humidity and high dew points during what was already a significant heat wave baking the region during the hottest time of the year. Dew points were unusually high along and near the coasts, frequently in the 70s, compared to more typical dew points in the 40s and 50s. Dew points ... http://weathercurrents.com/sanjacinto//NewsItemDisplay.do?Id=1685 The Extreme Heat Watch previously issued by the National Weather Service for a large portion of Southern California from 10 AM Tuesday until 8 PM Friday, has been upgraded to an Extreme Heat Warning covering the same timeframe. The difference between both advisories is mainly due to the increased heat threat, with temperatures in areas under the Extreme Heat Warning now forecast to reach up to 110 degrees during the peak of the heat wave. In addition, this also raises the risk for heat-related illnesses across affected populations. Very warm nights, with low temperatures significantly above average, will provide little to no relief from the excessive daytime heat. The Heat Advisory currently in effect across much of the region, will remain in place until 10 AM Tuesday with no changes. As a reminder, the National Weather Service cautions the public to drink plenty of fluids, stay out of the sun and in an air-conditioned room if/when possible, and check up on relatives and neighbors.