Dry and warmer weather through the weekend as gusty Santa Ana winds continue across the mountains into the inland valleys as an area of low pressure nears the region. This low pressure system will move southward into northern Mexico and will bring a small chance for light rain over San Diego County by late Sunday into Monday. Temperatures drop a little for Monday and Tuesday then high pressure will move over the region for much of next week, bringing dry and warmer weather.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
, New Aviation Discussion for the 12z TAF package,
This morning, a few mid and high clouds are moving from northeast to southwest across Socal in the northeast flow aloft around a closed upper low over the Lower Colorado River Valley. Surface pressure gradients are offshore and trending stronger. The combination of offshore pressure gradients and northeast flow aloft is enough to produce northeast winds gusting as high as 53 mph in the windiest locations this past hour.
The closed upper low will continue to migrate to the southwest, reaching a position off the central coast of Baja on Sunday. The Santa Ana winds will likely peak later today, producing strong northeast to east winds gusting mostly 40 to 50 mph with isolated gusts to 65 mph in the favored locations before gradually weakening through Monday. Socal can expect dry and warmer weather today and Sunday. Sunday will likely be the warmer day with daytime high temperatures reaching the mid 80s in the valleys and coastal areas, and the upper 80s in the low deserts.
The upper low will remain to our south through Monday and could bring some moisture from the sub-tropics into SoCal with the return flow on the north side of the low. This will bring a slight chance for light showers from late Sunday night through Monday, mostly to the mountains of San Diego County but light showers could also develop over the low deserts, inland valleys and southern portions of the Riverside County mountains. Rainfall totals are unlikely to exceed 0.10 inch
The closed upper low will begin to move northeast late Monday, reaching the New Mexico as an open wave by late Tuesday. The return of onshore flow and the marine layer will bring lower temperatures for Tuesday, especially west of the mtns, along with areas of coastal low clouds and fog during the nights and mornings.
For Wednesday through the end of the week, a ridge of high pressure building over the west coast will bring a return of unseasonably warm weather. Thursday and Friday will likely be the warmest days with temperatures reaching the low 90s in the inland valleys, the upper 70s to mid 80 in the coastal areas, the 70s in the mtns, the low 80s in the high deserts and the upper 90s in the low deserts.
071145z. Coast/Valleys, VFR with SKC to FEW high clouds AOA 20,000ft MSL. N/NE gusts 20-30 kts, increasing more significantly after 14z to 35-50 kts through the Inland Empire (below the Cajon Pass) and 25-40 kts throughout Orange County. Winds decrease slightly after 21z (still elevated 20-35kts), then greater confidence for more significant wind weakening after 02z Sun, though periods of gusty winds are possible through Sunday afternoon. Localized areas of LLWS and mod up/down drafts expected, especially in the lee of mountains.
Moderate confidence for gusts above 30 kts at KSNA, 15-20z. Moderate to high confidence for gusts above 35 kts at KONT, 14-22z.
.Mountains/Deserts, VFR with SKC to FEW high clouds AOA 20,000ft MSL. Periods of gusty N/NE winds expected through Sunday, sustained at 20-35 kts, and gusts 25-45 kts with isolated gusts to 55 kts through mountain passes and on coastal facing foothills. Localized areas of LLWS and mod up/down drafts in lee (south of) mountains mainly in San Bernardino County. Peak gusts in SB/OC/Riv Co. mtns 12- 20z; peak gusts over SD Co. mtns not until after 00z Sun. BLDU possible through the period with reduced VIS to 3SM or less at times.
Low confidence on gusts exceeding 35 kts at KPSP today, most likely 12-16z.
Intermittent gusts near 20 knots possible in the outer coastal waters near San Clemente Island this morning. Otherwise, no additional hazardous marine conditions are expected through Wednesday.
Ca, Wind Advisory until 5 PM PST Sunday for Orange County Inland Areas-Riverside County Mountains-San Bernardino County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Mountains-San Diego County Valleys-San Gorgonio Pass near Banning-Santa Ana Mountains and Foothills.
PZ, None.
