textproduct: San Diego

SYNOPSIS

A low pressure system moving into Baja will bring a slight chance of showers to southern San Diego County early this morning and again for this afternoon. Onshore flow will return today with high temperatures cooler than Sunday, as much as 20 to 25 degrees cooler near the coast. Inland areas will begin to warm on Tuesday with much greater warming for the valleys on Wednesday and coastal areas on Thursday with weak to locally moderate strength offshore flow. The coast and valleys will cool for Saturday into Sunday, but with high temperatures mostly remaining 15 to 20 degrees above average. For next week, strong high pressure aloft and occasional weak offshore lower flow will bring widespread record heat to inland areas.

SHORT TERM (Today through Wednesday)

A low pressure system off the coast of central Baja will move slowly eastward and inland across central Baja tonight, then accelerate eastward on Tuesday. A band of showers and isolated thunderstorms across northern Baja early this morning will mostly remain just south of the Mexican border this morning. A second band of showers for this afternoon could be far enough north to impact portions of San Diego County with chances for measurable precipitation greatest across southern San Diego County at 15 to 25 percent.

High temperatures today will be cooler, as much as 20 to 25 degrees cooler near the coast. The deserts will begin to warm on Tuesday. Much greater warming is expected on Wednesday, with high temperatures for the inland valleys and lower elevations of the mountains as much as 10 to 15 degrees warmer than Tuesday. High temperatures on Wednesday will range from around 70 near the coast to the 80s for the Inland Empire with the lower deserts in the mid 80s to lower 90s.

LONG TERM (Thursday through Sunday)

Strengthening high pressure aloft off the southern California coast and offshore flow will bring additional warming on Thursday with high temperatures for coastal areas as much as 10 to 15 degrees warmer than Wednesday. On Thursday, high temperatures for much of the coast and valleys except near the coast will be 20 to 25 degrees above average. High temperatures on Thursday will range from the lower to mid 80s near the coast to the upper 80s to mid 90s for the valleys and inland Orange County with the lower deserts in the mid to upper 90s. High temperatures will continue to warm another few degrees for inland areas on Friday with high temperatures for the Coachella close to all-time record highs for March each day for Friday through Sunday.

A brief return of onshore flow for the weekend could bring some cooling for the coast into the valleys, but with Sunday high temperatures still around 10 degrees above average near the coast to 20 to 25 degrees above average for the inland valleys with the deserts around 20 degrees above average. High temperatures on Sunday would range from the mid to upper 70s near the coast to the lower to mid 90s for the inland valleys with the lower deserts around 100.

Even hotter weather is likely for inland areas next week, with new all-time record high temperatures for March likely to be set for Palm Springs and Thermal. For Tuesday through Thursday of next week for Thermal, NBM has a 50 percent chance or greater each day to reach or exceed 110. If that were to happen, that would be the earliest date for Thermal to reach 110 by about two months. For Palm Springs, the NBM chance to reach or exceed 110 is 25 percent on both Wednesday and Thursday of next week.

AVIATION

091730Z...SCT-BKN clouds AOA 10000 feet MSL through the afternoon in San Diego County, except down to 8000 feet in any -SHRA near the Mexico border. Gradual clearing to occur after 02Z. Patchy low clouds to develop generally after 08Z into Tuesday morning, but with low confidence of cigs impacting coastal airports for much time, most likely at KSNA and 30% chance at KONT. Any cigs would be based around 2000-2500 feet MSL.

MARINE

No hazardous marine conditions are expected through Saturday.

SKYWARN

Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions.

SGX WATCHES/WARNINGS/ADVISORIES

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