textproduct: San Diego

SYNOPSIS

Fair and warmer weather is expected through the end of the week. There will be periods of high clouds this week, along with patchy coastal fog Wednesday and Thursday mornings. Brisk westerly winds will develop for late Wednesday in the mountains and deserts.

DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE

SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES...

Through Wednesday...

High pressure continues to build in over the region as the ridge further strengthens with a high approaching 590 dm over the Pacific waters to our southwest. This will allow for continued warming and drying conditions. High temperatures today will be generally on the slightly warmer side for most locations, and especially for the deserts. There could be a return to the marine layer for some of the coastal locations beginning tonight, and perhaps patchy fog along the coastal slopes where it intersects, if it does end up forming. Weak offshore winds overnight may help to prevent this.

Thursday through early next week...

The ridge will continue to expand northward with temperatures gradually increasing each day through Friday, which will likely be the warmest day of the week for most locations, with highs being as much as 15-20 degrees above the seasonal average for this time of year, especially within the IE and lower deserts. Going into the weekend, the ridge will finally begin to break down as we transition from being dominated by a longwave ridge, to a weak longwave trough, over the region. This will allow for temperatures to begin to cool back down closer to the seasonal average by Monday. In terms of the marine layer, based on guidance and a persistence of onshore flow returning, this should become more predominant overnight towards the end of the week and into the weekend, and will also continue to lift more going into Friday.

A little beyond the forecast period, there is at least some agreement with some of the deterministic members of split flow leading to a possible cut-off upper level low becoming stalled out over the region by the middle of next week, which may help to increase our chances of precipitation, and also help to keep us on the cooler side.

AVIATION

241030Z...Mostly clear and VFR conditions today and tonight. Variable high clouds AOA 20000 feet MSL. Patchy coastal fog after 06Z into Wednesday (10-30% chance) would be based around 200-400 feet MSL with vis 1-5SM at immediate coast. Cigs/vis issues not likely to impact coastal airports.

MARINE

No hazardous marine conditions 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.