High pressure will strengthen and move westward across the area through Saturday with high temperatures warming to 8 to 12 degrees above average for inland areas for the weekend with major to extreme HeatRisk for the deserts by Sunday. High temperatures will then cool around 5 degrees for inland areas through Wednesday with little change for low temperatures. Higher humidity will continue for coastal areas with increasing humidity for inland areas next week. Night and morning low clouds will continue for coastal areas.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
(today through Saturday), High pressure centered over New Mexico will move westward and strengthen through Saturday and be centered in the vicinity of Las Vegas on Saturday. High temperatures will warm a few degrees each day for today through Saturday, warming around 5 to locally 10 degrees for inland areas from Wednesday through Saturday.
High temperatures on Saturday will range from around 5 degrees above average near the coast to 8 to 12 degrees above average for inland areas. High temperatures on Saturday will range from around 80 near the coast to the upper 90s to 108 for the Inland Empire with 114 to 118 for the lower deserts. For Saturday, there will be major to locally extreme HeatRisk for the deserts, San Diego County mountains, moderate to major HeatRisk for the Inland Empire, and moderate or greater HeatRisk for most areas except at the beaches and for mountain elevations above 7500 feet.
The marine layer is around 1500 to 2000 feet deep. Coastal low clouds will spread into the western valleys early this morning. The marine mayer will slowly decrease in depth into the weekend with night and morning low clouds spreading inland mainly into just coastal areas and not into portions of the valleys.
(Sunday through Wednesday), High pressure will slowly weaken into the middle of next week. The axis of the high pressure will move northward just enough for the mid level flow across the area to become more easterly by the middle of next week. High temperatures for inland areas will decrease around 5 degrees from Saturday through Wednesday while surface dewpoints for inland areas will slowly increase with humidity slowing increasing.
Warm sea surface temperatures in the mid 70s, around 5 degrees above average, will maintain higher humidity for coastal areas into the western valleys. Low temperatures will change little, ranging from a few degrees above average for the coast into the western valleys with the mountains and deserts 5 to 10 degrees above average.
High temperatures for next Wednesday will range from around 80 near the coast to the mid 90s to 105 for the Inland Empire with 110 to 114 for the lower deserts. Low temperatures for the coast and valleys will be mostly in the mid 60s to lower 70s, in the 70s for the Apple and Lucerne Valleys, and in the mid 80s to lower 90s for the lower deserts.
HeatRisk will slowly decrease with HeatRisk for Wednesday of next week moderate to major for the deserts, and mostly moderate for the inland valleys, higher coastal terrain, and mountain areas below 7000 feet.
300600z. Coast/Valleys, Low clouds based 1000-1400ft MSL have already pushed inland around 10-15 miles and will filter in up to 20 miles by 12-14z. Intermittent IFR CIGs possible at coastal TAF sites, best chances between 10-14z. 70% chance for at least a brief CIG at KONT and a 20% chance for SBD, although both sites should at least see some reduced VIS due to HZ. Coastal terrain and western valleys, VIS down to 3-6SM possible. Clouds scatter out of the Inland Empire around 15-16z, clearing to the coast by 17-18z. Stratus may linger at some beaches in San Diego County through the afternoon. Low clouds based around 800-1100ft MSL develop and move inland again after 01z Fri.
Mountains/Deserts, Mostly SKC with unrestricted VIS through Thursday evening.
No hazardous marine weather is expected through Monday.
A 4-5 ft swell from 160-180 degrees with a period of 13-15 seconds associated with Hurricane Genevieve is currently moving into the coastal waters. Surf of 5-9 ft is expected on south facing beaches in Orange County with surf around 3-6 ft elsewhere. Surf will peak on Thursday and Friday, when the swell direction shifts to 180-190 degrees. Strong rip and longshore currents will create dangerous swimming conditions at most area beaches. In addition to the high surf, evening high tides will be above 6 ft this week. The combination of high tides and surf increases the risk of coastal flooding. The swell, period, and tides are expected to decrease over the weekend. Further information on all these hazards is found in the Coastal Hazard Message.
Ca, Coastal Flood Advisory until 3 AM PDT Saturday for Orange County Coastal Areas-San Diego County Coastal Areas.
High Surf Advisory until 5 PM PDT Saturday for Orange County Coastal Areas-San Diego County Coastal Areas.
Heat Advisory from 10 AM Friday to 8 PM PDT Sunday for Orange County Coastal Areas-San Diego County Coastal Areas.
Extreme Heat Warning from 10 AM Thursday to 8 PM PDT Sunday for Apple and Lucerne Valleys-Coachella Valley-Riverside County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Deserts-San Diego County Mountains-San Gorgonio Pass near Banning.
Extreme Heat Warning from 10 AM Friday to 8 PM PDT Sunday for Orange County Inland Areas-San Diego County Valleys-Santa Ana Mountains and Foothills.
Heat Advisory from 10 AM Thursday to 8 PM PDT Sunday for San Bernardino County Mountains.
PZ, None.
