| Day | Date | High/Low | Forecast |
| Fri | 6th | 67/55 | Some clouds but mostly sunny remainder of day. Partly cloudy evening. |
| Sat | 7th | 70/56 | Some morning clouds possible but mostly sunny day. Mostly clear evening. |
| Sun | 8th | 78/56 | Mostly sunny day with some high clouds possible. Mostly clear evening. |
| Mon | 9th | 71/54 | Mostly sunny day with scattered high clouds. Partly cloudy evening. |
| Tue | 10th | 65/52 | Mostly cloudy through the evening. Good chance of showers developing; Decrease chance of rain in the evening. |
Synopsis
A weak, upper level trough exists off the state coast today (responsible for recent, variable high clouds as well as return of some marine layer, low clouds). It is, however, just strong enough to promote some atmospheric instability over some mountains (mainly southern Sierras and Tehachapi Mountains). Afternoon radar imagery showed isolated showers and one thunderstorm (southern Kern County, as of this writing). The threat of mountain showers should end by early evening.
The center of the aforementioned trough is forecast to drop south before it can make landfall (somewhere in southern Baja California on Monday). High pressure aloft should nose into the state over the weekend. Marginal off-shore flow tomorrow may become a weak but full-fledged, off-shore flow on Sunday. Minor to modest warming is expected tomorrow. More noticeable warming should occur west of the mountains on Super Bowl Sunday, but it’s not expected to get as warm as with the previous warm spell (less widespread 80 degree weather and no 90 degree readings expected…high pressure aloft weaker upcoming event). Cooler weather will develop on Monday as off-shore flow transitions to on-shore flow (high pressure aloft drops south).
Last week, the numerical models were forecasting a significant shift in northeastern Pacific jet stream pattern for the week of the 9th. This change favored less persistent high pressure aloft over the state. The model consensus today continues to forecast this change for next week (enjoy the warm weather this Sunday…such weather may not return for awhile). A new, stronger, upper level trough should exist just off the state coast by Tuesday. Although model solutions vary on timing and wetness, it looks like southern California will experience some wet weather sometime in the Tuesday-Wednesday period (through Thursday, if a few model solutions are right). Most model solutions predict just a modest storm on Tuesday (0.25 – 0.50 inch rains in the lowland away from the mountains). There are still some scenarios that favor a weak storm reaching the Southland (favors less widespread precipitation, as well as lower storm totals…snow levels may not get below 6000 feet at height of storm).
A second storm could follow on Wednesday, but there has been a forecast trend of this system largely avoiding the Southland (storm center may drop south too far to the west to promote widespread, wet weather). At best, storm totals similar to the Tuesday storm may occur. If the Wednesday storm arrives more slowly than most scenarios favor currently, the threat of wet weather may include at least part of Thursday. In any case, a dry period is expected next Friday.
After that, most models show a colder, potentially wetter storm for the entire state sometime over the Presidents’ Day weekend. Potentially, a good but average, soaking storm is possible (0.75 – 1.50 inch rains in the lowlands away from the mountains). Showers could start in L.A. County as early as Valentine’s day evening, but most model solutions lean toward sometime on Sunday (currently leaning toward afternoon hours). A period of steady precipitation would give way to numerous showers and isolated thunderstorms on Monday (snow levels may fall below 5000 feet that day). Showers should exit the County Monday evening(16th) or Tuesday morning(17th). While far from certain, some model solutions show yet another storm later that week (modest strength).
Next issued forecast/synopsis should be on Monday, 9 February.