19/830 PM.
A cooling trend will continue through mid week as an approaching storm brings a return to onshore flow. Light to moderate rain is expected late Monday into Tuesday, focused over San Luis Obispo County with minimal impacts. Widespread gusty west to northwest winds will follow Wednesday through Friday.
(Sun-Wed), 19/812 PM.
Latest satellite and surface observations indicate mostly clear to partly cloudy skies as a batch of high clouds are drifting across the area this evening. Current sounding data indicates marine inversion around 800 feet in depth. Southwesterly winds, gusting in the 25-35 MPH, are observed across interior sections.
Forecast-wise for the short term, primary focus remains on the cutoff low, forecast to bring some wet and unsettled weather to the area. Latest model data indicates nothing to really deviate from current forecast. Rain will begin across SLO county late Monday afternoon/evening, then will spread south and east Monday night and Tuesday. By Tuesday evening, the rain will be tapering off, with dry conditions expected on Wednesday. Rainfall totals still look to be most impressive across SLO and SBA counties with widespread 0.50" to 1.00" totals and local amounts up to around 1.50" across some foothill areas. For Ventura and LA counties, the rain will lose some "oomph" with widespread totals of 0.33" or less with local amounts up to around 0.75 across the Ventura county mountains. Along with rain, there will be some increasing instability moving into northern areas on Tuesday. So, there will continue to be 15-20% chance of thunderstorms Tuesday, mainly across SLO county. Rainfall rates with this system are expected to be around 0.25" or less per hour. However, with any thunderstorm development, rates up to around 0.50" per hour will be possible. So, given the rainfall rates, no significant hydrologic issues are expected. Based on current snow level forecasts, no significant snowfall accumulation is anticipated in the local mountains.
As for winds, gusty southwesterly winds are expected Monday and Tuesday across interior sections and could flirt with advisory levels Tuesday afternoon/evening across the LA Mountains and Antelope Valley. On Wednesday, the winds will shift to a more west to northwest direction with advisory-level winds possible through the I-5 Corridor as well as the western half of the Santa Ynez Range.
As for temperatures, a noticeable cooling trend can be expected through Tuesday with highs on Tuesday about 4-8 degrees below normal for most areas. On Wednesday, temperatures will begin to rebound a few degrees, climbing to around normal levels.
(Thu-Sun), 19/214 PM.
Thursday and Friday will generally be free of any weather impacts with mostly clear skies and temperatures near to slightly below normal. This may continue through the weekend and into next week, however there are quite a few models indicating at least some very light rain, possibly as early as Saturday night along the Central Coast and Sunday morning in LA County. Most solutions show amounts under a quarter inch, and at least half of those, mainly south of Pt Conception, from nothing to a tenth of an inch.
19/2230z.
At 2200Z at KLAX, the marine layer was 700 feet deep. The top of the inversion was 2300 feet with a temperature of 17 degrees Celsius.
For 00Z TAF package, high confidence in CAVU conditions for KPRB, KSBA, KBUR, KVNY, KPMD and KWJF.
For KSBP, there is a 30% chance of LIFR/VLIFR conditions 09Z-16Z.
For KSMX, KLAX, KSMO, KLGB, KOXR and KCMA, there is a 30-40% chance that CIG/VSBY restrictions do not develop. If they do arrive, timing could be +/- 3 hours of current forecast and flight categories could be off by 1-2 categories.
KLAX, Moderate confidence in 00Z TAF. There is a 30% chance that CIG/VSBY restrictions do not develop. If they do develop, timing of arrival could be +/- 3 hours of current 08Z forecast and flight category could be +/- 1 category from current forecast. No significant easterly wind component is expected.
KBUR, High confidence in 00Z TAF as CAVU condition are expected through the period.
19/831 PM.
A storm system will move over the coastal waters Monday afternoon through Wednesday morning, bringing a chance of showers to much of the area. Cannot rule out a thunderstorm or two across the northern waters Tuesday morning.
SCA level southerly winds are expected to increase ahead of the cold front, and while SCA level winds are not forecast, there is a 20-30% chance that SCA gusts could occur at times Monday into Monday evening, and possibly again Tuesday afternoon. Tuesday evening winds will shift to the northwest behind the front, increasing to SCA level NW winds Wednesday afternoon. These winds will likely expand to include the majority of waters by Thursday afternoon. Wednesday night there is a 40% chance of Gale Force gusts over the southern waters, including portions of the nearshore waters inside the SoCal Bight, especially the Santa Barbara Channel. SCA winds may persist into the weekend at least for some waters.
Ca, NONE. PZ, NONE.
