Ation and Marine Sections,
Another dry, windy, mostly clear day today as moderate to strong Santa Ana winds blow down the foothills into the valleys. Peak winds this morning have been 40-50 mph downwind of the Cajon and Banning passes, 40-45 mph in the Santa Ana Mountain foothills, and up to 60-70 mph in the San Diego County foothills. Gusts are generally in the 30-45 mph range in the breezier valley of San Diego County and the Inland Empire, with gusts 15-30 mph as far as (parts of) the San Diego coast. These offshore winds have resulted in a very dry airmass, and humidity values in most areas are in the mid teens to 20 percents.
While offshore Santa Ana winds will continue through the rest of next week, the strongest period of winds is very likely to be this morning. Winds begin to diminish late this afternoon as the upper level low over central Baja California starts to move eastwards, and high pressure over the Great Basin weakens. Winds will still be moderate to locally strong through Monday afternoon, and the Wind Advisory remains in effect until mid-afternoon Monday for the mountains to the valleys. Winds continue to weaken through at least mid-week, so though offshore winds will linger they'll be in the weak to locally moderate range. Strongest winds will continue to be in the foothills and passes.
The warm, dry airmass will remain in place from the continued upper level ridge along with the offshore winds, and each afternoon will be slightly warmer through Wednesday/Thursday next week. Temperatures peak Wed-Thu at 5-10 degrees above average for the coasts and deserts and up to 15 degrees above average for mid- January in the valleys, where the forecast is for highs 70s into the low 80s. The dry airmass will make it difficult for anything but intermittent mid to upper level clouds to form through at least mid-week, and efficient radiative cooling each night will lead to cooler mornings this week for wind-sheltered areas.
By late next week (Friday-Saturday), while there are model differences, it looks likely that another wave will move into the northern Plains/Mid-West, which could provide the support to bump up the offshore winds again. At the moment, the more likely outcome is a fairly weak, brief increase in winds late Friday into Saturday, but not to the strength of today's winds. In any case, warm, dry, and mostly clear weather is very likely to continue through late next week.
Moderate to locally strong Santa Ana winds will continue along the coastal mountain slopes, foothills, and into the valleys through Monday. Periods of weaker Santa Ana winds will continue through the remainder of the week. A warming trend continues, with temperatures peaking around the middle of the week. Wednesday and Thursday will likely be the warmest days.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
, Updated Aviation and Marine Sections,
Another dry, windy, mostly clear day today as moderate to strong Santa Ana winds blow down the foothills into the valleys. Peak winds this morning have been 40-50 mph downwind of the Cajon and Banning passes, 40-45 mph in the Santa Ana Mountain foothills, and up to 60-70 mph in the San Diego County foothills. Gusts are generally in the 30-45 mph range in the breezier valley of San Diego County and the Inland Empire, with gusts 15-30 mph as far as (parts of) the San Diego coast. These offshore winds have resulted in a very dry airmass, and humidity values in most areas are in the mid teens to 20 percents.
While offshore Santa Ana winds will continue through the rest of next week, the strongest period of winds is very likely to be this morning. Winds begin to diminish late this afternoon as the upper level low over central Baja California starts to move eastwards, and high pressure over the Great Basin weakens. Winds will still be moderate to locally strong through Monday afternoon, and the Wind Advisory remains in effect until mid-afternoon Monday for the mountains to the valleys. Winds continue to weaken through at least mid-week, so though offshore winds will linger they'll be in the weak to locally moderate range. Strongest winds will continue to be in the foothills and passes.
The warm, dry airmass will remain in place from the continued upper level ridge along with the offshore winds, and each afternoon will be slightly warmer through Wednesday/Thursday next week. Temperatures peak Wed-Thu at 5-10 degrees above average for the coasts and deserts and up to 15 degrees above average for mid- January in the valleys, where the forecast is for highs 70s into the low 80s. The dry airmass will make it difficult for anything but intermittent mid to upper level clouds to form through at least mid-week, and efficient radiative cooling each night will lead to cooler mornings this week for wind-sheltered areas.
By late next week (Friday-Saturday), while there are model differences, it looks likely that another wave will move into the northern Plains/Mid-West, which could provide the support to bump up the offshore winds again. At the moment, the more likely outcome is a fairly weak, brief increase in winds late Friday into Saturday, but not to the strength of today's winds. In any case, warm, dry, and mostly clear weather is very likely to continue through late next week.
112130z, Coast/Valleys/Mountains, Mostly clear skies prevailing. Northeast and east winds easing slightly this afternoon and evening with gusts near 30-40 kts along coastal slopes and 25-35 kts downwind of the Cajon/Banning passes into the Inland Empire and parts of Inland Orange County/eastern San Diego Valleys. Weaker winds expected by Monday afternoon with the strongest gusts more confined to the mountain slopes near 25-35 kts.
Periods of LLWS with mod up/downdrafts downwind of coastal slopes, notably between 06-15Z Mon when strong winds are more likely to separate from the surface. Offshore wind pattern continues through the next few days, though weaker and more localized.
Deserts, VFR conditions through Sunday evening. Elevated northeast winds staying mostly confined to desert foothills with gusts up to 20 kts.
Localized easterly wind gusts near 20 knots sporadically through Monday morning. Otherwise, no hazardous marine conditions expected through Friday.
Ca, Wind Advisory until 2 PM PST Monday 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.
