Above average conditions will continue through Wednesday. Cooler conditions with increased cloud coverage is expected for Thursday through early next week. Periods of showers and increased winds are expected starting Friday through next Tuesday.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
Highs today are expected to be within a few degrees of yesterday. Weak ridging aloft and weak offshore flow will continue to keep highs above average. Along the coast, daytime highs are expected to run 10 to 15 degrees above average through Wednesday, with highs 5 to 10 degrees above average elsewhere. Thursday, highs will be up to 5 degrees cooler than Wednesday but will still be 5 to 10 degrees above average.
Thursday, an upper level low will dig south and east and is expected to pass through Northern Baja by early Friday. This will bring periods of mostly light showers to the coastal basin Friday into Saturday. There will be a modest increase in precipitable water, with some guidance showing a bump up in IVT on Friday. The ECMWF EPS has a 30% chance of IVT exceeding 250 kg/m/s (equates to a weak atmospheric river), while the GEFS has closer to a 60% chance. There is still quite a bit of spread in rainfall amounts, especially for areas north of San Diego County with some members still running completely dry. Solutions that usher more IVT into Southern California will lead to higher rainfall amounts across the area. Compared to yesterday, the upper end of potential rainfall totals has come down to under an inch. The NBM chances of exceeding 0.50" over 48 hours from Friday morning to early Sunday is 15-35% across the coastal basin.
Periods of showers are expected through the weekend into early next week as troughs line up to periodically pass across the US West Coast. A lot of the details will become clearer as the timing and track of each trough passage becomes clearer. After the Friday/Saturday timeframe, there may be periods of isolated light showers Sunday, but ensemble guidance is honing in on Monday/Tuesday for our next chance at widespread rainfall.
Winds are expected to increase over the mountains and deserts with each trough passage. Expect winds to increase as early as late Thursday and continue into Saturday morning. Peak gusts of 35 to 45 mph, with gusts up to 55 mph through wind prone passes. Winds are expected to increase again early next week with the next trough passage.
101830z, Mostly clear skies and VFR conditions through early Wed. Light E/NE winds west of mountain passes and foothill slopes.
No hazardous marine conditions are expected through Friday. Winds increase late Friday and seas build Saturday, which could lead to hazardous boating conditions.
Surf of 3-7 feet will lead to a high rip current risk and hazardous swimming conditions today, particularly in San Diego County. A Beach Hazards Statement in effect for these beaches through this evening contains the details.
Ca, Beach Hazards Statement until 10 PM PST this evening for San Diego County Coastal Areas.
Coastal Flood Advisory until noon PST today for Orange County Coastal Areas-San Diego County Coastal Areas.
PZ, None.
