La Mesa, CA Warnings, Watches and Advisories

When a severe thunderstorm warning is issued, the storm may produce damaging winds, large hail, dangerous lightning, and heavy rain. In some cases, heavy rainfall produced by a severe storm can also lead to flash flooding. Do not drive vehicles through flooded areas. The water depth or fast flowing water/mud/debris from a flash flood will make road conditions unsafe. Do not rely soley on data presented here or other third-party websites - always check your official national and local weather service agency website, socials, radio and/or TV stations for making critical decisions related to weather events.

Please carefully read each posted Warning and Alert as it relates to the area(s) being affected. We may provide a wider range of issued severe weather warnings for surrounding cities and counties, so some alerts may not directly impact this location. This is done to help with preparing for severe weather that may overlap or be heading towards La Mesa.

Use the Radar Maps link provided to understand the trajectory of a storm.

Red Flag Warning issued September 6 at 10:40AM PDT until September 6 at 8:00PM PDT by NWS Reno NV

The National Weather Service in Reno has issued a Red Flag Warning for gusty winds and low humidity, which is in effect until 8 PM PDT this evening. * Affected Area...Fire Weather Zone 274 Southern Mono County, Fire Weather Zone 421 Southern Sierra Front including Alpine, Northern Mono, Southern Lyon, and Western Mineral Counties, Fire Weather Zone 429 Lahontan Basin including Churchill and Eastern Mineral Counties. * Winds...Southwest 15 to 25 mph with gusts up to 40 mph. * Humidity...As low as 8 percent. * Duration...4 to 6 hours. * Impacts...The combination of gusty winds and low humidity can cause fire to rapidly grow in size and intensity before first responders can contain them.

Flood Advisory issued September 6 at 10:06AM PDT until September 6 at 1:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...West Central Los Angeles County in southwestern California...including the Franklin and Palisades burn scars... * WHEN...Until 100 PM PDT. * IMPACTS...Rises in small streams and normally dry washes. Water and minor rock falls over roadways. * ADDITIONAL DETAILS... - At 1001 AM PDT, Doppler radar and automated rain gauges indicated heavy rain. Minor flooding is ongoing or expected to begin shortly in the advisory area. Minor debris flows may occur in the recent burn scars. Between 0.25 and 0.5 inches of rain have fallen, so far. - Rainfall rates will generally range around 0.25 to 0.33 inch per hour. Isolated rates may reached 0.50 inch per hour for brief periods. - Some locations that will experience flooding include... Eastern Malibu, Encino, Santa Monica, Woodland Hills, Beverly Hills, Hollywood, Universal City, Pacific Palisades, Brentwood, Interstate 405 through the Sepulveda Pass, Bel Air, Topanga State Park, Sherman Oaks, Century City, Calabasas, Studio City and West Hollywood. - Recent burn scars including Franklin and Palisades burn scars. - http://www.weather.gov/safety/flood

Freeze Warning issued September 6 at 10:04AM PDT until September 7 at 9:00AM PDT by NWS Medford OR

* WHAT...Widespread frost, but also sub-freezing temperatures as low as 29 degrees expected. * WHERE...In California, Modoc, Northeast Siskiyou and Northwest Modoc Counties, and South Central Siskiyou Counties. In Oregon, Central and Eastern Lake, Klamath Basin, and Northern and Eastern Klamath and Western Lake Counties. This includes Klamath Falls, Lakeview, Alturas, McCloud, Dorris, Tulelake, Chiloquin, and Sprague River. * WHEN...From 3 AM to 9 AM PDT Monday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. * ADDITIONAL DETAILS...Freezing temperatures are also possible in much of the same area on Tuesday morning. The addition of some high clouds will be helpful, but dew points will be lower than on Monday morning.

Beach Hazards Statement issued September 6 at 2:32AM PDT until September 7 at 11:00PM PDT by NWS Eureka CA

* WHAT...Increased threat of sneaker waves expected. * WHERE...Southwestern Humboldt and Coastal Mendocino Counties. * WHEN...Through Monday evening. . * IMPACTS...Large, unexpected waves can sweep across the beach without warning, sweeping people into the sea from rocks, jetties, and beaches. These sneaker waves can also move large objects such as logs, crushing anyone caught underneath.

Lake Wind Advisory issued September 6 at 1:25AM PDT until September 6 at 11:00PM PDT by NWS Reno NV

* WHAT...Southwest winds 15 to 25 mph with gusts up to 35 mph. Wave heights up to 3 feet on Lake Tahoe and Pyramid Lake. * WHERE...Greater Lake Tahoe Area, Lassen-Eastern Plumas-Eastern Sierra Counties, Mono County, Mineral and Southern Lyon Counties, Greater Reno-Carson City-Minden Area, and Western Nevada Basin and Range including: Lake Tahoe, Pyramid Lake, Eagle Lake, Honey Lake, Lake Davis, Frenchman Lake, Stampede, Boca, and Prosser Creek Reservoirs, Donner Lake, Fallen Leaf Lake, Washoe Lake, Lahontan Reservoir, Topaz Lake, Walker Lake, Bridgeport Reservoir, Mono Lake, and Lake Crowley. * WHEN...From 11 AM this morning to 11 PM PDT this evening. * IMPACTS...Strong winds and rough waves on area lakes will create hazardous conditions for small craft.

High Surf Advisory issued September 6 at 12:24AM PDT until September 8 at 11:00PM PDT by NWS San Diego CA

* WHAT...Large breaking waves of 6 to 10 feet for south and southwestern-facing beaches and 4 to 7 feet for west-facing beaches. Strong and dangerous rip and longshore currents. Minor coastal flooding from a combination of high surf and high astronomical tides. * WHERE...San Diego County coastal areas and Orange County coastal areas. * WHEN...Now through 11 PM PDT Tuesday. * IMPACTS...Flooding of lots, parks, and roads with only isolated road closures expected. Dangerous swimming and surfing conditions and beach erosion. * ADDITIONAL DETAILS...Predicted tides for La Jolla, CA: Sat, Sep 5 2026: 6.0 feet at 4:48 PM PDT Sun, Sep 6 2026: 6.3 feet at 6:03 PM PDT Mon, Sep 7 2026: 6.7 feet at 7:03 PM PDT Tue, Sep 8 2026: 6.8 feet at 7:54 PM PDT.

Coastal Flood Advisory issued September 6 at 12:24AM PDT until September 8 at 11:00PM PDT by NWS San Diego CA

* WHAT...Large breaking waves of 6 to 10 feet for south and southwestern-facing beaches and 4 to 7 feet for west-facing beaches. Strong and dangerous rip and longshore currents. Minor coastal flooding from a combination of high surf and high astronomical tides. * WHERE...San Diego County coastal areas and Orange County coastal areas. * WHEN...Now through 11 PM PDT Tuesday. * IMPACTS...Flooding of lots, parks, and roads with only isolated road closures expected. Dangerous swimming and surfing conditions and beach erosion. * ADDITIONAL DETAILS...Predicted tides for La Jolla, CA: Sat, Sep 5 2026: 6.0 feet at 4:48 PM PDT Sun, Sep 6 2026: 6.3 feet at 6:03 PM PDT Mon, Sep 7 2026: 6.7 feet at 7:03 PM PDT Tue, Sep 8 2026: 6.8 feet at 7:54 PM PDT.

High Surf Advisory issued September 5 at 8:10PM PDT until September 8 at 11:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...For the Coastal Flood Advisory, moderate coastal flooding expected. For the High Surf Advisory, large breaking waves of 5 to 8 feet with local sets to 10 feet and dangerous and potentially life threatening rip currents, largest on south- facing shores. * WHERE...Catalina and Santa Barbara Islands, Ventura County Beaches, Malibu Coast and Los Angeles County Beaches. * WHEN...Until 11 PM PDT Tuesday. * IMPACTS...There is an increased risk for ocean drowning. Rip currents will be widespread and very strong, potentially pulling swimmers and surfers out to sea. Large breaking waves can cause injury, wash people off beaches and rocks, and capsize small boats near shore. Enhanced beach erosion will occur. Flooding of sea water is likely, around the time of high tide, over vulnerable low-lying coastal areas such as parking lots, beaches, and walkways. Areas most susceptible to coastal flooding will include Avalon, Long Beach (Alamitos Peninsula), and Oxnard to Malibu (including Point Mugu). * ADDITIONAL DETAILS...High tides will occur around 6.7 feet at 6pm on Sunday, 7 feet at 7pm on Monday, and 7.2 feet at 8pm on Tuesday.

Coastal Flood Advisory issued September 5 at 8:10PM PDT until September 8 at 11:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...For the Coastal Flood Advisory, moderate coastal flooding expected. For the High Surf Advisory, large breaking waves of 5 to 8 feet with local sets to 10 feet and dangerous and potentially life threatening rip currents, largest on south- facing shores. * WHERE...Catalina and Santa Barbara Islands, Ventura County Beaches, Malibu Coast and Los Angeles County Beaches. * WHEN...Until 11 PM PDT Tuesday. * IMPACTS...There is an increased risk for ocean drowning. Rip currents will be widespread and very strong, potentially pulling swimmers and surfers out to sea. Large breaking waves can cause injury, wash people off beaches and rocks, and capsize small boats near shore. Enhanced beach erosion will occur. Flooding of sea water is likely, around the time of high tide, over vulnerable low-lying coastal areas such as parking lots, beaches, and walkways. Areas most susceptible to coastal flooding will include Avalon, Long Beach (Alamitos Peninsula), and Oxnard to Malibu (including Point Mugu). * ADDITIONAL DETAILS...High tides will occur around 6.7 feet at 6pm on Sunday, 7 feet at 7pm on Monday, and 7.2 feet at 8pm on Tuesday.

Beach Hazards Statement issued September 5 at 8:10PM PDT until September 8 at 11:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Dangerous and potentially life threatening rip currents and breaking waves due to elevated surf expected. * WHERE...San Luis Obispo County Beaches, Santa Barbara County Central Coast Beaches, Santa Barbara County Southwestern Coast and Santa Barbara County Southeastern Coast. * WHEN...Through Tuesday evening. * IMPACTS...There is an increased risk of ocean drowning. Rip currents will be widespread and very strong, potentially pulling swimmers and surfers out to sea. Waves can wash people off beaches and rocks. Pooling of sea water is possible around high tide at beach areas that is uncommon with normal tidal ranges. Enhanced beach erosion is also possible. No significant damage is expected. * ADDITIONAL DETAILS...High tides will occur around 6.3 feet at 630pm on Sunday, 6.5 feet at 730pm on Monday, and 6.5 feet at 830pm on Tuesday.

Beach Hazards Statement issued September 5 at 10:37AM PDT until September 7 at 11:00PM PDT by NWS San Francisco CA

* WHAT...Increased risk of sneaker waves and strong rip currents due to incoming long period southerly swell associated with tropical activity in the Eastern Pacific Ocean. Breaking waves to around 10 feet expected. * WHERE...Pacific Coast beaches. * WHEN...Through 11 PM PDT Monday. * IMPACTS...Dangerous conditions are forecast along the shoreline. Hazards include sneaker waves, strong rip currents, and large breaking waves.