| Day | Date | High/Low | Forecast |
| Mon | 27th | 65/54 | Some morning clouds but mostly sunny day; Possibly breezy at times in the afternoon. Mostly clear evening. |
| Tue | 28th | 68/55 | Some clouds but mostly sunny day. Mostly clear evening. |
| Wed | 29th | 68/56 | Chance of morning low clouds; Otherwise, mostly sunny day. Chance of evening low clouds. |
| Thu | 30th | 69/56 | Partly cloudy through the evening. |
| Fri | 1st May | 72/56 | Chance of some morning low clouds; Otherwise, mostly sunny day. Mostly clear evening. |
Synopsis
The storm that passed through southern California this past Saturday wasn’t much for many in L.A. County. Occasional light showers were the rule for most in the L.A. Basin, but measurable rainfall in the L.A. County lowlands was mainly restricted to the southeast County. Even that was under a tenth inch with the exception around LAX airport. A couple of heavy intensity showers (brief duration late Saturday into the beginning of Sunday) amounted to about a third to half an inch rainfall (not sure why that spot favored higher rainfall). As predicted by the computer models, more widespread, quarter to half inch rain fell to the east and south of L.A.County (one to two inch rainfall for some San Bernardino mountain locales).
Like yesterday, it’s another breezy afternoon in many locales. However, wind speeds are noticeably lower than it got yesterday. UCLA recorded a peak gust of 28 mph yesterday but so far, it hasn’t exceeded 19 mph (potentially could see values into the low 20s late afternoon). An upper level trough responsible for the breezy weather is weakening and moving off to the east. So, things should be more typical after today (brisk, afternoon sea breezes in some areas but more manageable…shouldn’t lose a cap to the wind).
Weak high pressure aloft will make a brief appearance late tonight through tomorrow morning. It’s not forecast to purge today’s marine layer, but should make it shallower and possibly dilute it in places (limited low cloud coverage, in theory). However, a different though weak trough will near the Southland late tomorrow. This pattern should limit warming tomorrow in most locales (should be slightly cooler than normal despite a predicted, brief, marginal off-shore flow). That second trough should promote widespread, marine layer clouds on Wednesday morning. Daytime temperatures should be comparable to Tuesday values in most areas.
A third trough is predicted to move from west to east but to the south of southern California (valid period Thursday). At one time, some model solutions favored scattered showers in parts of the Southland. That scenario isn’t cancelled entirely, but odds don’t favor any shower threat in L.A. County. I show “partly cloudy” for Thursday, but depending on the location of the third trough, cloud cover may wind up more or less.
A new high pressure ridge should reach the Southland on Friday. It should stick around for Saturday as well. At this point, most model solutions don’t favor temperatures rising too greatly. It should be slightly warmer than normal, but there is potential for well inland areas to reach 80 degrees (campus area shouldn’t exceed mid-70s). A cooling cycle should begin on Sunday, but should be minor at first.
The longer range period is still uncertain. It concerns a predicted, “cut-off” low pressure (“cut-off” low is weather person’s woe). Model agreement on when it reaches the West Coast (moving west to east in the eastern Pacific) is currently poor. Slightly cooler than normal weather could get here as early as next Monday or be delayed a couple of days. A chance of showers in the Southland will depend on strength and location of the low pressure (how close the center gets). I will end this discussion now as speculation runs high.
Next issued forecast/synopsis should be on Thursday, 30 April.