| Day | Date | High/Low | Forecast |
| Fri | 21st | 69/53 | Mostly sunny day with scattered high clouds. Some evening high clouds. |
| Sat | 22nd | 68/54 | Chance of some early morning fog/low clouds; Otherwise, mostly sunny day with some high clouds. Some evening high clouds. |
| Sun | 23rd | 72/56 | Mostly sunny day with some high clouds. Scattered evening high clouds. |
| Mon | 24th | 79/59 | Sunny day. Mostly clear evening. |
| Tue | 25th | 78/57 | Sunny day. Mostly clear evening. |
Synopsis
A little precipitation fell over parts of northern California a couple days ago, but high pressure aloft has kept southern California dry for most of the week (minor storm did produce some light rain earlier on Monday afternoon). Minor fluctuations in the wind flow pattern are anticipated through tomorrow. A passing, weak trough aloft should promote a brief period of on-shore flow. It may be enough for a brief return of marine layer clouds/fog early tomorrow (some existed around coastal San Diego County early today). With or without low clouds/fog, there should be minor cooling west of the mountains tomorrow (relative to today’s highs).
Starting on Sunday, high pressure aloft should develop more strongly (encompassing the entire state). Marginal off-shore flow conditions are expected for at least a few days (peak strength Monday). Much above normal temperatures are likely by Monday (Tuesday too away from the immediate coast). Isolated 90 degree readings are probable in the coastal valleys. The predicted lack of a full fledged, off-shore flow should prevent the coastal plain from getting that warm, but even areas near the coast potentially could reach the 80 degree mark for a day or two (stayed a bit conservative for today’s campus forecast).
A weak, subtropical trough aloft should promote some cooler weather by the middle of next week. Temperatures should remain slightly above normal at first (unless the trough turns out stronger than currently forecast). A storm is forecast to affect northern California around Thursday (minor precipitation event). The only relevant affect on the Southland should be stronger on-shore flow (partly cloudy skies too… some high clouds; possibly low clouds too). A little cooler weather should develop toward the end of the week (effects of on-shore flow an developing trough off the coast.
Most of the longer range models show an opportunity for multiple storms to affect the state. Most of these storms should be limited to northern California. The model consensus predicts minor to average wet events (beginning with the one expected on Thursday). There are some model solutions showing some wet weather reaching Santa Barbara County before March ends, but it’s far from certain. There is one model scenario (from ECMWF model) that shows a decent soaking storm for the entire state around the 1st of April (April Fools joke?). I’d like to see a few more similar solutions before jumping onto that band wagon. At the least, the last few days of March and beginning of April should be cooler than normal.
Next issued forecast/synopsis may be on Monday, 24 March.