| Day | Date | High/Low | Forecast |
| Mon | 10th | 83/66 | Mostly sunny remainder of day with some, mainly distant clouds possible. Some evening high clouds possible. |
| Tue | 11th | 81/66 | Chance of some early morning low clouds; Otherwise, mostly sunny day with some mid/high clouds. Chance of late evening low clouds. |
| Wed | 12th | 78/65 | Good chance of early morning low clouds; Otherwise, mostly sunny day with some high clouds. Evening low clouds likely. |
| Thu | 13th | 76/65 | Good chance of morning low clouds; Otherwise, mostly sunny day with some high clouds. Evening low clouds likely. |
| Fri | 14th | 76/65 | Good chance of morning low clouds; Otherwise, mostly sunny day. Chance of evening low clouds. |
Synopsis
No surprise (predicted by the numerical models last week), but high pressure aloft continues its dominance across the southwestern states. Still, it has weakened slightly since its peak strength late last week. All the models predict the high pressure migrating east enough to allow a low pressure trough to form along the West Coast (by midweek). A long awaited cooling trend should promote cooler than normal, daytime temperatures across the entire Southland (not just the coastal plain).
The temperature at UCLA has reached at least 80 degrees for a fifth day in a row (Downtown L.A. fourth consecutive 90 degree day). It’s only the second such streak this summer (other was 23 – 27 July). It’s still one day short of the most consecutive 80 degree days this year so far (six days 16 – 21 March). That possibly will be tied tomorrow, assuming the sea breeze doesn’t start up too early at UCLA.
The current, “monsoon” moisture incursion into southern California seems to be keeping the local, low cloud field from forming a solid blanket (most of Santa Monica Bay was clear of low clouds this morning). However, slowly strengthening on-shore flow and an upper trough formation along the West Coast should promote widespread low clouds in the coming day (clouds should reach the coastal valleys by the latter half of the week). Even as the “monsoon” incursion is predicted to lessen over the Southland mountains/deserts by the end of the week, greater marine air influence should keep the muggy factor on the high side this week (west of the mountains). That’s thanks to the local ocean being warmer then normal (mid-70s off the Orange, San Diego County waters). If air from the open waters to the northwest gets entrained into the local marine layer, then, it may not be as muggy as I’m currently anticipating.
Most of the models weaken the aforementioned, West Coast trough this weekend. So, temperatures should make some upward recovery (valid for well inland areas). Some of the models show high pressure aloft nosing back into the Southwest early next week. If true, interior sections should get warmer than normal again, but those models show just moderate warming (not getting as hot as recent days). Modest warming would also occur for most areas west of the mountains (at or slightly warmer than normal). There are some models that show the upper trough re-asserting itself along the state coast by the middle of next week (more limited warming cycle). Which scenario is right is still uncertain.
Next issued forecast/synopsis should be on Monday, 17 August.