11/103 PM.
Several degrees of cooling are expected Tuesday and Wednesday as an upper low moves through northern California. Low clouds and fog will move into the coastal valleys then clearing to near the coast by afternoon. Gusty winds are possible at times across the mountains and deserts. Slight warming is expected Thursday and Friday.
(tdy-Thu), 11/143 PM.
High pressure aloft and a slight weakening of the onshore flow helped warm temperatures away from the immediate coast today. Meanwhile, low clouds and fog hugged the coastline and most beaches were socked in all day except for a small portion of Malibu and around Long Beach.
Most of the forecast after today remains on track. High pressure will start to weaken and shift east Tuesday followed by an upper low moving through northern California Wednesday. This will start a significant trend for coast and coastal valleys Tuesday, and far interior areas Wednesday. Following the upper low passage northerly flow aloft will increase across the Santa Ynez Range and western Transverse Range creating increasing northerly winds in those areas, mainly from late afternoon through the early morning hours. Forecast ensemble gradients are still in the -3 to -5 range, which would likely be strong enough for wind advisories in the Santa Ynez Range.
One potential change for tomorrow is models are indicating almost a low grade monsoon pattern into the mountains and deserts associated with a very weak upper low moving up from Baja. There is a slight increase in PW's and instability tomorrow but moisture currently is still lacking. The latest high res models are showing winds coming from the southeast through early afternoon as that feature moves north, then shifting back to a typical southwest direction in the afternoon. Thunderstorms have not been added to the forecast, but the consensus is that there is a 5-10% chance of a shower or brief storm across the Antelope Valley or adjacent mountains.
A slight warming trend is expected to begin Thursday, mainly for areas away from the immediate coast.
(Fri-Mon), 11/144 PM.
Building high pressure and continued offshore flow from the north will greatly reduce or eliminate the low clouds on Friday. There will be a decent bump up in temps of 3 to 6 locally 8 degrees across the area.
Further warming Saturday with limited or no marine layer clouds will bring max temps into the 70s across the csts and 80s in the vlys or 3 to 6 degrees over normal.
Weak troffing will move into the area next Sunday. In addition there will be an increase in the onshore flow to the east. Max temps will likely fall a degree or 2 over most areas.
In addition the northerly gradients will likely bring advisory level wind gusts to the western portion of the SBA south coast late in the afternoons and evenings.
11/2054z.
High confidence in KWJF and KPMD TAFs.
Low to moderate confidence in remainder of TAFs. Timing of flight category changes may be off by 3 hours and one flight category. There is a 40-50 percent chance of IFR or lower cigs/vsbys for KBUR and KVNY 10-16Z.
KLAX, Moderate confidence in TAF. No significant east wind expected.
KBUR, Low confidence in TAF. There is a 50 percent chc of 2SM BR OVC004 conds 10Z-16Z.
11/149 PM.
Winds and seas will remain below Small Craft Advisory (SCA) levels overnight through Tuesday.
Wednesday night through the weekend, winds and seas will start to strengthen/build, with SCA winds across the outer waters starting late Wednesday night and Seas reaching steep and choppy SCA levels around Friday night. There is a 20-40 percent chance of SCA winds across the inner waters, with the highest chances each afternoon and evenings. GALE Force winds will be possible across the outer waters as early as Thursday afternoon, with highest (30-50 percent) chances on Saturday into Sunday.
Large SCA level seas of 10-12+ feet will be possible for the outer and northern waters by this weekend.
Dense fog will be possible this evening through mid morning Tuesday.
Ca, NONE. PZ, NONE.
