| Day | Date | High/Low | Forecast |
| Mon | 29th | 73/63 | Sunny remainder of day. Chance of evening low clouds |
| Tue | 30th | 72/61 | Good chance of morning low clouds; Sunny afternoon. Chance of evening low clouds. |
| Wed | 1st October | 74/61 | Chance of early morning low clouds; Otherwise, mostly sunny day. Chance of late evening low clouds. |
| Thu | 2nd | 75/62 | Chance of early morning low clouds; Otherwise, mostly sunny day. Chance of evening low clouds. |
| Fri | 3rd | 74/62 | Good chance of morning low clouds but mostly sunny by late morning. Chance of evening low clouds. |
Synopsis
An upper level, “cut-off” low pressure that brought showers and some thunderstorms (mostly mountain/desert region) late last week has passed. It also contributed to a deep marine layer that produced drizzle/light rain in places, including UCLA. Today, we’re under the influence of a weak ridge of high pressure. Areal low cloud coverage this morning was much less than in previous days, but daytime temperatures remain below normal (overnight low temperatures closer to normal today as water vapor content finally dropped more toward normal for this time of year).
A new Pacific, upper level trough will move through the state tomorrow. It should promote widespread, marine layer clouds again tonight into tomorrow. Although I didn’t include it in the campus forecast, I wouldn’t be surprised if spotty, early morning drizzle/light rain were to occur. Clearing is anticipated for the afternoon hours, but it’s possible that little or only partial clearing occurs tomorrow (similar to what occurred in recent days).
High pressure aloft over Mexico is forecast to bulge into the Southwest Tuesday night through Thursday morning. It should help weaken the on-shore flow again, and that should lead to less extensive low clouds for Wednesday-Thursday. Despite more sunshine, only a minor warming trend is expected in the coastal plain. At best, well inland areas may experience a return to seasonable temperatures.
Yet another trough is forecast for Friday. This one may stick around the state through early next week, if a number of computer model forecasts are right. Cooler weather is anticipated. Depending on what model solution verifies, another round of marine layer induced drizzle may occur (not necessarily same locales each day). Also, some models depict a decent on-shore flow early next week that may promote breezy weather in the interior.
Some of the longer range models showed a potential, weak off-shore flow around the middle of next week (accompanied by slightly warmer than normal daytime temperatures). However, many model solutions tend to keep some form of trough along the West Coast for next week. For now, I’m expecting mostly sunny days after Monday of next week with near seasonable temperatures.
Next issued forecast/synopsis should be on Monday, 6 October.