Near normal temperatures expected this weekend. Thunderstorm chances over the mountains each afternoon Sunday through the forecast period. Above average high and low temperatures return early to mid next week. Coastal flooding will impact beaches Sunday through Tuesday with evening high tides exceeding 7 feet.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
, UPDATED AVIATION DISCUSSION,
As of 1 AM, low clouds had started to spread into the western valleys with areas of high clouds streaming overhead. The presence of high clouds does not seem to be deterring the development of low clouds, with low clouds expected to linger into mid-morning in some locations along the coast.
Highs today will be within 5 degrees of highs Friday, with the deserts expected to be a few degrees cooler with 3 to 5 degrees of warming in the Inland Empire and Orange County and minimal change in San Diego county. Both high and low temperatures are expected to run above average for the middle of the week which will bring areas of moderate to major HeatRisk to inland locations. Current forecast has the heat peaking on Wednesday.
The area of high pressure that was sitting over us over the past few days will be nudged north and east to the Four Corners region by Sunday. That will allow for subtropical moisture to make it's way into Southern California. This will bring increased chances of showers and thunderstorms mainly to the mountains each afternoon and evening this week. Any thunderstorms that develop will be accompanied by gusty and erratic winds, lightning, and brief, heavy rainfall. Right now there is a 10-20% chance an isolated storm moves off the mountains and into the valleys or deserts, with the highest chances of that occurring being in the High Desert.
For the first half of the week, Monday looks like the most likely day for more widespread showers and thunderstorms to develop over the mountains. It looks like by the middle of the week, the high will shift further east which will limit, but not completely remove shower and thunderstorm chances. While there is uncertainty in the upper level pattern for the latter half of next week, about 31 percent of ensemble solutions position the high in a more favorable position for increased chances of afternoon showers and thunderstorms in the mountains by Thursday with 48 percent of solutions more favorable by next Friday.
111200z. Coast/Valleys, Locally reduced vis 3-5SM where stratus nears terrain in the western valleys. There is a 40% chance of IFR cigs/vis restrictions at KONT 12-15Z. Low clouds with bases 900-1400 ft MSL clearing 16-19Z Saturday, then redeveloping after 03Z Sunday, with similar bases, and then continue to spread and fill into the valleys, stretching to around 15-20 miles inland. Otherwise increasing mid/high clouds at/above 15,000 ft MSL throughout the day.
Mountains/Deserts, Increasing mid/high clouds at/above 15,000 ft MSL and unrestricted visibility. There is a slight chance of a shower over the mountains this afternoon.
No hazardous marine conditions are expected through Friday.
Ca, Beach Hazards Statement from Sunday morning through Tuesday evening for Orange County Coastal Areas-San Diego County Coastal Areas.
PZ, None.
