Sun Valley, CA Warnings, Watches and Advisories

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 Sun Valley.

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

Red Flag Warning issued August 27 at 10:46PM PDT until August 28 at 3:00PM PDT by NWS San Francisco CA

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 AM TO 3 PM PDT FRIDAY DUE TO LIGHTNING FOR SANTA CRUZ MOUNTAINS, SOUTHERN SALINAS VALLEY/ARROYO SECO AND LAKE SAN ANTONIO, SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST, NORTHERN SALINAS VALLEY/HOLLISTER VALLEY AND CARMEL VALLEY, NORTHERN MONTEREY BAY, AND SOUTHERN MONTEREY BAY AND BIG SUR COAST... ....The potential for isolated thunderstorms across the Central Coast continues to increase from Friday morning through Friday afternoon... * AFFECTED AREA...The Salinas and Carmel Valleys and Hollister Area, Monterey Bay and the Big Sur Coast, The Santa Cruz Mountains, and Interior Monterey County and the Santa Lucia Range. * TIMING...From 5 AM to 3 PM PDT Friday. * THUNDERSTORMS...Lightning strikes with little precipitation and gusty and erratic outflow winds of 40 to 50 mph. * IMPACTS...There will be an increased risk for power outages. Lightning strikes may result in new fire ignitions. Erratic outflow winds will result in rapid fire spread for both new and existing fires.

Extreme Heat Warning issued August 27 at 10:30PM PDT until August 28 at 8:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Dangerously hot conditions with temperatures up to 96. * WHERE...Santa Ynez Mountains Eastern Range and Santa Ynez Mountains Western Range. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events.

Extreme Heat Warning issued August 27 at 10:30PM PDT until August 28 at 8:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Hot daytime conditions with high temperatures between 92 and 102 common. Warm overnight conditions will bring less relief than usual. * WHERE...Most coastal areas of Los Angeles, Ventura, and southern Santa Barbara Counties. * WHEN...Until 8 PM PDT Friday. * IMPACTS...There is a high risk for dangerous heat illness, especially for sensitive groups like the very young, the very old, those without air conditioning, and those active outdoors.

Extreme Heat Warning issued August 27 at 10:30PM PDT until August 28 at 8:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Dangerously hot conditions with temperatures up to 93. * WHERE...Santa Barbara County Southwestern Coast. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events.

Extreme Heat Warning issued August 27 at 10:30PM PDT until August 28 at 8:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Hot daytime conditions with high temperatures between 100 and 110 common. Warm overnight conditions will bring less relief than usual. * WHERE...Most mountains and valleys of Los Angeles, Ventura, and Santa Barbara Counties. * WHEN...Until 8 PM PDT Friday. * IMPACTS...There is a high risk for dangerous heat illness, especially for sensitive groups like the very young, the very old, those without air conditioning, and those active outdoors.

Heat Advisory issued August 27 at 10:30PM PDT until August 28 at 8:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Hot daytime conditions with high temperatures between 90 and 100 common. * WHERE...San Luis Obispo County Inland Central Coast, Santa Barbara County Inland Central Coast, and Santa Ynez Valley. * WHEN...Until 8 PM PDT Friday. * IMPACTS...There is a high risk for dangerous heat illness for sensitive groups like the very young, the very old, those without air conditioning, and those active outdoors. * ADDITIONAL DETAILS...This advisory has been extended to now end on Friday. While temperatures will peak through Thursday, humidities will rise on Friday largely mitigating any relief from the heat.

Heat Advisory issued August 27 at 10:30PM PDT until August 28 at 8:00PM PDT by NWS Los Angeles/Oxnard CA

* WHAT...Hot daytime conditions with high temperatures between 95 and 105 common. * WHERE...San Luis Obispo County Interior Valleys, San Luis Obispo County Mountains, Santa Lucia Mountains, and Southern Salinas Valley. * WHEN...Until 8 PM PDT Friday. * IMPACTS...There is a high risk for dangerous heat illness for sensitive groups like the very young, the very old, those without air conditioning, and those active outdoors.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures of 112 to 114 expected. Low temperatures will be mostly in the mid 80s to mid 90s. * WHERE...Coachella Valley, San Diego County Deserts, and San Gorgonio Pass near Banning. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Overnight temperatures 5 to 10 degrees above normal will limit relief from the heat.

Heat Advisory issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...High temperatures in the low 90s to 102 expected. * WHERE...Riverside County Mountains. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 10 to 15 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Heat Advisory issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...High temperatures in the 90s below 6000 feet expected. * WHERE...San Bernardino County Mountains below 6000 feet. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 10 to 15 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures in the mid 90s to 102 expected. * WHERE...San Diego County Mountains. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 10 to 15 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures from 100 to 108 expected. Overnight low temperatures will be mostly in the 70s. * WHERE...San Bernardino and Riverside County Valleys-The Inland Empire. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 5 to 10 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness across populations.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures in the upper 90s in the western valleys to around 103 in the inland valleys expected. Low temperatures will be mostly in the 70s. * WHERE...San Diego County Valleys. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 5 to 10 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Heat Advisory issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...High temperatures in the mid 80s near the beaches to the mid to upper 90s for the mesas and other higher coastal terrain expected. Low temperatures will be mostly in the 70s. * WHERE...San Diego County Coastal Areas. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures in the upper 90s to 105 expected. * WHERE...Apple and Lucerne Valleys. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 5 to 10 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Heat Advisory issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...High temperatures in the mid 80s near the beaches to the lower to mid 90s for higher coastal terrain expected. Low temperatures mostly in the 70s. * WHERE...Orange County Coastal Areas. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures in the mid 90s to 102 expected. Low temperatures will be mostly in the 70s. * WHERE...Orange County Inland Areas. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 5 to 10 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Extreme Heat Warning issued August 27 at 9:05PM PDT until August 28 at 8:00PM PDT by NWS San Diego CA

* WHAT...Dangerously hot conditions with high temperatures in the mid 90s to 103 expected. * WHERE...Santa Ana Mountains and Foothills. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Low temperatures 5 to 10 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.

Red Flag Warning issued August 27 at 1:33PM PDT until August 28 at 3:00PM PDT by NWS Los Angeles/Oxnard CA

...RED FLAG WARNING IN EFFECT THROUGH 3 PM FRIDAY FOR MANY INTERIOR PORTIONS OF SOUTHWEST CALIFORNIA DUE TO EXTREME HEAT AND INSTABILITY ALONG WITH LOCALLY GUSTY WINDS AND LOW HUMIDITIES... ...RED FLAG WARNING IN EFFECT FROM FRIDAY 5 AM THROUGH 3 PM ACROSS ALL OF SAN LUIS OBISPO COUNTY TO DO POTENTIAL FOR DRY LIGHTNING... .A very hot and unstable air mass combined with locally gusty winds and low humidities will bring a significant risk of large plume dominated fires with rapid spread and extreme fire behavior. Additionally, tropical moisture streaming across our area will bring a 15-25 percent chance of thunderstorms to the region, with a moderate risk for frequent fire starts across San Luis Obispo County due to dry lightning potential. The National Weather Service in Los Angeles/Oxnard has issued a Red Flag Warning for potential for dry lightning, which is in effect from 5 AM to 3 PM PDT Friday. * THUNDERSTORMS...Moderate risk for dry lightning with minimal rain as well as gusty and erratic winds. * TEMPERATURES...Highs 100 to 110 across the lower mountains, adjacent foothills, and 85 to 95 across higher mountains. Very deep mixing heights of 10,000 to 15,000 feet today, slightly lower on Friday. * IMPACTS...Moderate risk for frequent fire starts associated with dry lightning. Additionally, there is a significant risk of large plume dominated fires with rapid fire spread and extreme fire behavior.

Red Flag Warning issued August 27 at 1:33PM PDT until August 28 at 3:00PM PDT by NWS Los Angeles/Oxnard CA

...RED FLAG WARNING IN EFFECT THROUGH 3 PM FRIDAY FOR MANY INTERIOR PORTIONS OF SOUTHWEST CALIFORNIA DUE TO EXTREME HEAT AND INSTABILITY ALONG WITH LOCALLY GUSTY WINDS AND LOW HUMIDITIES... ...RED FLAG WARNING IN EFFECT FROM FRIDAY 5 AM THROUGH 3 PM ACROSS ALL OF SAN LUIS OBISPO COUNTY TO DO POTENTIAL FOR DRY LIGHTNING... .A very hot and unstable air mass combined with locally gusty winds and low humidities will bring a significant risk of large plume dominated fires with rapid spread and extreme fire behavior. Additionally, tropical moisture streaming across our area will bring a 15-25 percent chance of thunderstorms to the region, with a moderate risk for frequent fire starts across San Luis Obispo County due to dry lightning potential. * TEMPERATURES...Highs 96 to 106 across the lower elevations. Highs 85 to 95 common across the higher mountains. Lows in the mid 70s to mid 80s common in the mountains and foothills. Very deep mixing heights of 12,000 to 17,000 feet today, slightly lower on Friday. * WINDS...Southwest 10 to 20 mph with gusts 20 to 30 mph this afternoon into early evening. * RELATIVE HUMIDITY...Minimum humidities 12 to 25 percent. Poor recoveries overnight hours in the mountains and foothills with humidities in the 15 to 30 percent range. * IMPACTS...There is a significant risk of large plume dominated fires with rapid fire spread and extreme fire behavior. There is a history of large plume dominated fires this time of year with similar weather and fuel conditions, including the Bridge, Bobcat, and Station fires.

Red Flag Warning issued August 27 at 1:33PM PDT until August 28 at 3:00PM PDT by NWS Los Angeles/Oxnard CA

...RED FLAG WARNING IN EFFECT THROUGH 3 PM FRIDAY FOR MANY INTERIOR PORTIONS OF SOUTHWEST CALIFORNIA DUE TO EXTREME HEAT AND INSTABILITY ALONG WITH LOCALLY GUSTY WINDS AND LOW HUMIDITIES... ...RED FLAG WARNING IN EFFECT FROM FRIDAY 5 AM THROUGH 3 PM ACROSS ALL OF SAN LUIS OBISPO COUNTY TO DO POTENTIAL FOR DRY LIGHTNING... .A very hot and unstable air mass combined with locally gusty winds and low humidities will bring a significant risk of large plume dominated fires with rapid spread and extreme fire behavior. Additionally, tropical moisture streaming across our area will bring a 15-25 percent chance of thunderstorms to the region, with a moderate risk for frequent fire starts across San Luis Obispo County due to dry lightning potential. The National Weather Service in Los Angeles/Oxnard has issued a Red Flag Warning for potential for dry lightning, which is in effect from 5 AM to 3 PM PDT Friday. * THUNDERSTORMS...Moderate risk for dry lightning with minimal rain as well as gusty and erratic winds. * TEMPERATURES...Highs 100 to 110 across the lower mountains, adjacent foothills, and 85 to 95 across higher mountains. Very deep mixing heights of 12,000 to 17,000 feet today, slightly lower on Friday. * IMPACTS...Moderate risk for frequent fire starts associated with dry lightning. Additionally, there is a significant risk of large plume dominated fires with rapid fire spread and extreme fire behavior.

Red Flag Warning issued August 27 at 1:33PM PDT until August 28 at 3:00PM PDT by NWS Los Angeles/Oxnard CA

...RED FLAG WARNING IN EFFECT THROUGH 3 PM FRIDAY FOR MANY INTERIOR PORTIONS OF SOUTHWEST CALIFORNIA DUE TO EXTREME HEAT AND INSTABILITY ALONG WITH LOCALLY GUSTY WINDS AND LOW HUMIDITIES... ...RED FLAG WARNING IN EFFECT FROM FRIDAY 5 AM THROUGH 3 PM ACROSS ALL OF SAN LUIS OBISPO COUNTY TO DO POTENTIAL FOR DRY LIGHTNING... .A very hot and unstable air mass combined with locally gusty winds and low humidities will bring a significant risk of large plume dominated fires with rapid spread and extreme fire behavior. Additionally, tropical moisture streaming across our area will bring a 15-25 percent chance of thunderstorms to the region, with a moderate risk for frequent fire starts across San Luis Obispo County due to dry lightning potential. * TEMPERATURES...Highs 100 to 110 across the lower mountains, adjacent foothills and the Cuyama Valley, and 85 to 95 across higher mountains. Very deep mixing heights of 12,000 to 17,000 feet today, slightly lower on Friday. * WINDS...Local west to north winds 15 to 25 mph with gusts up to 35 mph at times, strongest across the I-5 and Highway 33 corridors. A slightly stronger northerly wind push is possible late tonight into Friday morning, with gusts up to 40 mph possible across the I-5 corridor and other favored interior mountain passes. * RELATIVE HUMIDITY...Minimum humidities 12 to 25 percent. Poor recoveries overnight hours in the mountains and foothills with humidities in the 15 to 30 percent range. * IMPACTS...There is a significant risk of large plume dominated fires with rapid fire spread and extreme fire behavior. There is a history of large plume dominated fires this time of year with similar weather and fuel conditions, including the Bridge, Bobcat, and Station fires.

Extreme Heat Warning issued August 27 at 1:17PM PDT until August 28 at 8:00PM PDT by NWS Las Vegas NV

* WHAT...Dangerously hot conditions expected through the work week, with temperatures up to 115 to 118 across Death Valley and the Colorado River Valley; up to 108 to 112 across Moapa Valley, the Las Vegas Valley, the Pahrump Valley, and the Morongo Valley; up to 90 to 95 in the Hualapai Mountains. Overnight lows will be in the upper-80s to low-90s for desert valleys. * WHERE...Portions of northwest Arizona, southeast California, and southern Nevada. * WHEN...Until 8 PM PDT /8 PM MST/ Friday. * IMPACTS...Heat-related illnesses increase significantly during extreme heat events.

Extreme Heat Warning issued August 27 at 11:37AM MST until August 28 at 8:00PM MST by NWS Phoenix AZ

* WHAT...Dangerously hot conditions. Afternoon temperatures 103 to 113. Major Heat Risk. * WHERE...Chuckwalla Mountains, Salton Sea, Chiriaco Summit, and Joshua Tree NP East. * WHEN...Until 8 PM PDT Friday. * IMPACTS...Overexposure can cause heat cramps and heat exhaustion to develop and, without intervention, can lead to heat stroke.

Extreme Heat Warning issued August 27 at 11:37AM MST until August 29 at 8:00PM MST by NWS Phoenix AZ

* WHAT...Dangerously hot conditions. Afternoon temperatures 106 to 115. Major to Extreme Heat Risk. * WHERE...Portions of southwest Arizona and southeast California. * WHEN...Until 8 PM MST /8 PM PDT/ Saturday. * IMPACTS...Increase in heat related illnesses, including heat cramps, heat exhaustion, and heat stroke. Heat stroke can lead to death.

Air Quality Alert issued August 25 at 7:55AM PDT by NWS Los Angeles/Oxnard CA

* WHAT...The South Coast AQMD has issued an air quality alert due to harmful levels of ozone pollution. Visit https://www.aqmd.gov/alertinfo to check current and forecasted air quality levels. * WHERE...in the the South Coast Air Basin and Coachella Valley. Levels of ozone pollution can vary by time and location depending on emissions and air pollution transport. * WHEN...from 1 PM Monday to 8 PM Friday. The highest ozone levels typically occur in the afternoon and early-evening hours. * IMPACTS... Ozone air pollution can cause serious health problems, including trouble breathing, asthma attacks, and lung damage. Everyone can be affected, but sensitive groups such as people with lung disease, older adults, people who are pregnant, children, and those who spend a lot of time outdoors are at greater risk.

Air Quality Alert issued August 25 at 6:39AM PDT by NWS Los Angeles/Oxnard CA

* WHAT...The South Coast AQMD has issued an air quality alert due to harmful levels of ozone pollution. Visit https://www.aqmd.gov/alertinfo to check current and forecasted air quality levels. * WHERE...in the the South Coast Air Basin and Coachella Valley. Levels of ozone pollution can vary by time and location depending on emissions and air pollution transport. * WHEN...from 1 PM Monday to 8 PM Friday. The highest ozone levels typically occur in the afternoon and early-evening hours. * IMPACTS... Ozone air pollution can cause serious health problems, including trouble breathing, asthma attacks, and lung damage. Everyone can be affected, but sensitive groups such as people with lung disease, older adults, people who are pregnant, children, and those who spend a lot of time outdoors are at greater risk.

Air Quality Alert issued August 24 at 1:34PM PDT by NWS San Diego CA

* WHAT...The South Coast AQMD has issued an air quality alert due to harmful levels of ozone pollution. Visit https://www.aqmd.gov/alertinfo to check current and forecasted air quality levels. * WHERE...in the the South Coast Air Basin and Coachella Valley. Levels of ozone pollution can vary by time and location depending on emissions and air pollution transport. * WHEN...from 1 PM Monday to 8 PM Friday. The highest ozone levels typically occur in the afternoon and early-evening hours. * IMPACTS... Ozone air pollution can cause serious health problems, including trouble breathing, asthma attacks, and lung damage. Everyone can be affected, but sensitive groups such as people with lung disease, older adults, people who are pregnant, children, and those who spend a lot of time outdoors are at greater risk.