textproduct: San Diego

SYNOPSIS

Inland warming will begin today with greater warming for all areas for Wednesday and Thursday with widespread record heat for most areas for Thursday and Friday. Onshore flow will bring some cooling for the coast into the valleys during the weekend while the deserts continue to slowly warm. This long-duration heat wave for the deserts, valleys, and inland coastal areas will continue for much of next week.

SHORT TERM (Today through Thursday)

Low pressure centered over northern and central Baja will weaken and accelerate towards the east moving into Texas by Wednesday. High pressure aloft will strengthen over southern California through Thursday with weak offshore lower-level flow developing on Thursday.

Satellite imagery shows patches of low clouds extending from the outer coastal waters to the coastal slopes of the mountains with fairly limited coverage overall. The marine inversion will gradually strengthen and lower into Thursday. Coverage of low clouds is expected to increase each night, but with low clouds not spreading as far into the valleys each night.

The stronger north to northeast winds on Thursday are expected to be near and below the Cajon Pass and along and below the coastal slopes of the Santa Ana Mountains with the stronger gusts to 30 to 40 mph.

The greatest warming of high temperatures for today, of 4 to 8 degrees, is expected for the lower deserts. Warming is expected for all areas on Wednesday with high temperatures warming as much as 10 to 15 degrees for the inland valleys onto the lower coastal slopes of the mountains. On Thursday, high temperatures will warm another 4 to 8 degrees for the deserts, mountains, and inland valleys with the coast and western valleys warming 10 to 15 degrees.

High temperatures on Thursday will be around 14 to 18 degrees above average for the deserts into the mountains, and mostly 20 to 25 degrees above average for the coast, valleys, and lower coastal slopes of the mountains. For the coast and valleys, high temperatures near the coast will be in the lower to mid 80s with high temperatures in the western valleys and inland Orange County mostly in the mid 90s with the lower deserts in the mid to upper 90s.

The currently forecast high temperatures for most areas on Thursday would be near to exceeding the existing high temperature record for the date. There could also be a few records broken for warmest overnight temperatures for the date, mostly in the mountains and inland valleys. Heat Risk will increase to moderate for much of the coast and valleys except near the coast and in the more inland portions of the Inland Empire. With moderate heat risk, heat-related illnesses are likely for sensitive populations.

LONG TERM (Friday through Monday)

High temperatures on Friday will continue to warm another few degrees at lower elevations to around 5 degrees for the mountains. With that warming, high temperatures for portions of the western valleys and inland coastal areas will be as much as 25 to 30 degrees above average. High temperatures on Friday will be in the 80s near the coast and mostly in the 90s for the valleys and inland coastal areas. The lower deserts will be mostly in the upper 90s to around 100. Most locations could set new record high temperatures for the date on Friday with some locations in the lower deserts close to their all-time record for March. On Friday, the moderate Heat Risk will expand to include more of the coast and valleys and much of the lower deserts.

Onshore flow for the weekend will cool high temperatures for the coast and valleys as much as 4 to 8 degrees for the western valleys and inland coastal areas on Saturday and another few degrees on Sunday for coastal areas and the far western valleys. The deserts will warm another few degrees on Saturday with the deserts, mountains, and inland valleys warming another few to around 5 degrees on Sunday.

On Sunday, high temperatures will be as much as 25 to 30 degrees above average for the lower elevations of the mountains and inland portions of the Inland Empire. High temperatures on Sunday will range from the mid to upper 70s near the coast to the 90s for the inland valleys with 100 to 104 for the lower deserts.

High temperature records are most likely to be broken on Saturday and Sunday for the deserts, mountains, and portions of the inland valleys. Most areas in the lower deserts could set new high temperature records for March on Sunday, in some cases exceeding the records set only a day or two prior.

Most areas will warm another few degrees on Monday with widespread record or near-record high temperatures for the deserts, mountains, valleys, and inland Orange County. Record or near- record heat is likely to continue for inland areas for much of next week.

AVIATION

101125Z...Patchy low clouds currently with bases ranging from 600- 2200ft MSL. Clouds generally lower in Orange/Riverside/San Bernardino counties (sub-1000ft MSL) with higher bases for San Diego County. Clouds will gradually scatter out between 15-19z, with VFR expected to prevail thereafter. FEW-SCT marine layer clouds near 2500-3000ft MSL may stick around near the coast into the afternoon. Low clouds expected to re-increase in coverage for the coastal areas after 03z Wednesday, with CIGs at most coastal/inland TAF sites by 06-09z. Bases generally expected to be 1000-2000ft MSL.

MARINE

No hazardous marine conditions are expected through Saturday.

SGX WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...None.