Warm and dry weather will continue each afternoon through Friday with cool nights and mostly clear skies. A cooler and wetter pattern will enter the region this weekend into early next week. Some areas may see rainfall by Saturday, others shortly thereafter. Snow levels will be high, so expect rain for most mountain communities. Confidence on exact details are slowly coming together, but still low at this time. Another round of wetter weather may occur into early next week as well.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
No significant changes to the forecast this evening as stable high pressure continues over the area.
Previous discussion from 1:55 pm Wednesday November 20th, 2024
(Thursday through Saturday), Satellite continues to show clear skies over SoCal as high pressure dominates the Southwest. Light winds and warm weather will continue through Friday as high pressure maintains its hold over the Desert Southwest. NBM chances for temperatures to reach into the lower 80s will be highest by Thursday. Chances are lower for the San Diego valleys 10-40%, 30-60% across the Inland Empire and 50-80% in the lower deserts.
A storm to the north currently impacting Northern California and the Pacific Northwest will drift southward this weekend. The atmospheric river associated with this storm will move closer to our region by Saturday, becoming weaker per latest IVT output values near 250-400 kg/m/s. Model trends from EPS and GEFS continue to show drier solutions on Saturday for our area, so confidence on the start time of any precipitation is slowly increasing on a later start. Trimmed back larger POPs so most areas along and west of the mountains see a 20-40% chance of precip by Saturday evening. If any precip falls from this weakening AR, northern areas will be favored to see the rain earliest along with higher totals. Some leftover showers may make it south toward San Diego County by Saturday night or Sunday morning. Whatever occurs, confidence is high that rain totals will be light. Snow levels will be high with this system as well, over 8,000 feet.
(Sunday into middle of next week)A series a shortwaves will rotate within the upper level trough the weekend into early next week. One of these waves may be deep enough to bring another chance of precipitation later on Sunday through early Tuesday. Model ensembles continue to show widespread differences, but if this occurs we may be able to see some heavier rain and high elevation snow. Confidence on these details by this time are still on the low end. My confidence is higher that we will continue to see a troughing pattern overhead, which will be indicative of cooler and breezier weather across the area. Long range models diverge a bit by the middle of next week, some showing slight warming and drying, others showing more cooler and breezier weather. We will continue to monitor the outlook for Thanksgiving, which may not be calm and dry.
210430z, Aside from some upper level cirrus clouds, mostly clear skies and VFR conditions prevail through Thursday evening.
No hazardous marine weather conditions expected through Monday.
Ca, None. PZ, None.
