San Francisco, California
Regional Weather Alerts
| Alert: | Extreme Heat Warning |
| Area(s): | Lake Havasu and Fort Mohave; Lake Mead - AZ side; Lake Mohave - AZ side; Hualapai Mountains; Northwest Deserts; Death Valley National Park; Eastern Mojave Desert, Including the Mojave National Preserve; Morongo Basin; Cadiz Basin; San Bernardino County-Upper Colorado River Valley; Northeast Clark County; Western Clark and Southern Nye County; Las Vegas Valley; Southern Clark County; Lake Mead - NV side; Lake Mohave - NV side |
| Effective: | 2026-08-19 @ 6:11 am -> 2026-08-20 @ 7:00 am |
| Onset: | 2026-08-19 @ 6:11 am -> 2026-08-21 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Las Vegas NV on 2026-08-19 @ 6:11 am |
| Headline: | Extreme Heat Warning issued August 19 at 4:11AM PDT until August 21 at 8:00PM PDT by NWS Las Vegas NV |
| Description: |
* WHAT...Dangerously hot conditions with temperatures up to 115 to 118 degrees expected through Death Valley and the lower Colorado River Valley, with highs between 107 to 110 degrees elsewhere. * 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. |
| Alert: | Heat Advisory |
| Area(s): | Cuyama Valley; Santa Clarita Valley; Southern Salinas Valley; San Luis Obispo County Interior Valleys; San Luis Obispo County Mountains; Santa Ynez Mountains Western Range; Santa Barbara County Interior Mountains; Calabasas and Agoura Hills; Western San Fernando Valley; Eastern San Fernando Valley; Santa Susana Mountains; Southern Ventura County Mountains; Western San Gabriel Mountains and Highway 14 Corridor; Eastern San Gabriel Mountains; Los Angeles County San Gabriel Valley |
| Effective: | 2026-08-19 @ 4:48 am -> 2026-08-20 @ 6:00 pm |
| Onset: | 2026-08-19 @ 4:48 am -> 2026-08-20 @ 10:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Los Angeles/Oxnard CA on 2026-08-19 @ 4:48 am |
| Headline: | Heat Advisory issued August 19 at 2:48AM PDT until August 20 at 8:00PM PDT by NWS Los Angeles/Oxnard CA |
| Description: |
* WHAT...High temperatures of 92 to 105 expected, with most areas seeing peak heat on Wednesday and Thursday. Low temperatures are expected to range from the upper 60s to lower 70s at lower elevations to the mid 70s to lower 80s in the foothills and mountains. * WHERE...A portion of southwest California. * WHEN...Until 8 PM PDT Thursday. * IMPACTS...Hot temperatures may cause heat illnesses. Warmer than normal low temperatures will add to the heat discomfort. * ADDITIONAL DETAILS...The heat advisory may need to be extended into Friday for portions of the forecast area, but there remains considerable uncertainty at this time. |
| Alert: | Heat Advisory |
| Area(s): | San Bernardino and Riverside County Valleys-The Inland Empire |
| Effective: | 2026-08-19 @ 2:58 am -> 2026-08-19 @ 5:30 pm |
| Onset: | 2026-08-19 @ 12:00 pm -> 2026-08-20 @ 10:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS San Diego CA on 2026-08-19 @ 2:58 am |
| Headline: | Heat Advisory issued August 19 at 12:58AM PDT until August 20 at 8:00PM PDT by NWS San Diego CA |
| Description: |
* WHAT...Temperatures up to 105 expected. * WHERE...San Bernardino and Riverside County Valleys-The Inland Empire. * WHEN...From 10 AM this morning to 8 PM PDT Thursday. * IMPACTS...Hot temperatures may cause heat illnesses. |
| Alert: | Extreme Heat Warning |
| Area(s): | Coachella Valley; San Diego County Deserts; San Gorgonio Pass Near Banning |
| Effective: | 2026-08-19 @ 2:58 am -> 2026-08-19 @ 5:30 pm |
| Onset: | 2026-08-19 @ 12:00 pm -> 2026-08-21 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS San Diego CA on 2026-08-19 @ 2:58 am |
| Headline: | Extreme Heat Warning issued August 19 at 12:58AM PDT until August 21 at 8:00PM PDT by NWS San Diego CA |
| Description: |
* WHAT...Dangerously hot conditions with temperatures up to 112 expected. * WHERE...Coachella Valley, San Diego County Deserts, and San Gorgonio Pass near Banning. * WHEN...From 10 AM this morning to 8 PM PDT Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. |
| Alert: | Extreme Heat Warning |
| Area(s): | Parker Valley; Kofa; Yuma; Central La Paz; Southeast Yuma County; Gila River Valley; Imperial County Southwest; Imperial County Southeast; Imperial County West; Imperial Valley; Palo Verde Valley; Chuckwalla Valley |
| Effective: | 2026-08-19 @ 2:14 am -> 2026-08-19 @ 5:30 pm |
| Onset: | 2026-08-19 @ 2:14 am -> 2026-08-21 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Phoenix AZ on 2026-08-19 @ 2:14 am |
| Headline: | Extreme Heat Warning issued August 19 at 12:14AM MST until August 21 at 8:00PM MST by NWS Phoenix AZ |
| Description: |
* WHAT...Dangerously hot and humid conditions. Afternoon temperatures 106 to 114 expected. Major Heat Risk. * WHERE...Portions of southwest Arizona and southeast California. * WHEN...Until 8 PM MST /8 PM PDT/ Friday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. Overexposure can cause heat cramps and heat exhaustion to develop and, without intervention, can lead to heat stroke. |