24/1241 PM.
A shallower marine layer is expected over the next few days. Warm weather will peak on today and continue into Thursday. A cooling trend with a more pervasive marine layer cloud pattern and below normal temperatures is expected Friday into the weekend.
(tdy-Sat), 24/1241 PM.
A 590 dm ridge is currently situated over Socal. This ridging is expected to break down on Thursday and will be replaced with zonal to cyclonic flow as another trough develops over PACNW and dives into the Great Basin through the weekend.
Onshore flow will strengthen to the north through Thursday and to the east through Saturday. This will result in gusty SW winds across the interior - strongest across the Antelope Valley/ft hills and portions of LA county mtns. Approaching advisory levels Thursday into Friday, and even better chances into the weekend. Advisory level Sundowner winds likely on Friday, and especially on Saturday. Focused across western Santa Ynez range.
With increasing onshore flow, decreasing 500 mb heights, and increasing potential for Catalina Eddy (throughout the week) this will result in the continuation of marine layer stratus across the coasts and valleys.
Temperatures are expected to be warmest today and a couple degrees cooler tomorrow (still warm/hot). Then, a noticeable cooling trend Friday into the weekend.
Important: Have adjusted the Heat advisory end time to 9 PM Wednesday for zone 368 - Los Angeles Inland Coast including Downtown. All other zones are still under a heat advisory through 9 PM Thursday. See NPWLOX for more details.
(Sun-Wed), 24/1241 PM.
June Gloom will be back with a vengeance during the xtnd period. By Sunday, an unseasonably cold upper low will be situated over the Great Basin region. This main low will lift to the NE on Monday. In Tandem, a shortwave will drop south on the backside and will maintain troughing over the west coast. There is some uncertainty in how far south the energy dives.
Chances for advisory level winds linger into Sunday across the Antelope Valley/adjacent foothills and I-5 corridor. Lower confidence beyond due to uncertainty in upper pattern and sfc pressure gradients.
At least moderate onshore flow to the north and east is expected to continue Monday through Wednesday. Look for plenty of night through morning low clouds across the csts/vlys every day. Clearing will be on the slow side and a few beaches will remain cloudy in the afternoon. Portions of the SBA south coast may be the exception as local north flow indicated by the KSBA-KSMX gradients may keep the low clouds away or to a lesser extent.
Temperatures are likely to remain below normal through end of fcst period. Max temps will mostly be in the 70s across the csts/vlys (mid to upper 60s at the beaches) and only lower to mid 80s for the inland areas. These max temps are 3 to 5 degrees cooler than normal at the csts and 5 to 10 locally 12 below normal across the vlys and inland areas.
24/1835z.
At 1720Z at KLAX, the marine layer was 1000 feet deep. The top of the inversion was 3400 feet with a temperature of 22 C.
Low to moderate confidence in the KPRB TAF with the National Blend only indicating a 30 to 40 percent chance of MVFR CIGs.
Moderate confidence in the remainder of the TAFs. The National Blend indicates a 70+ percent chance of LIFR CIGs at KSBP, KSMX, KSBA, KOXR, with a 50 to 60 percent chance at KCMA and KSMO.
KLAX, Low to moderate confidence in TAF. Opted for persistence forecast with LIFR CIGs again beginning 08Z, although the National Blend only features a 45 percent chance of sub-1K CIGs early Thursday morning with high confidence in VFR conditions by 16Z.
KBUR, Moderate confidence in TAF. Less than 30 percent probability of LIFR and a 60 percent chance of MVFR between 13z and 17z.
24/656 AM.
High confidence in winds and seas remaining below Small Craft Advisory (SCA) levels through today. Local gusts could reach 21 kts near Point Conception and across the western Santa Barbara Channel later this afternoon into the evening. Chances for SCA criteria gusts increase Thursday evening across the northern waters and will expand to the south Friday into the weekend. SCA winds will be strongest on Saturday, and will reach into the nearshore waters along the Central Coast and Santa Barbara Channel at times. Seas will near 10 ft Saturday evening through Monday morning. Thereafter, conditions look to quiet down a bit through mid next week.
Ca, Heat Advisory remains in effect until 9 PM PDT Thursday for zones 88-372-373-379-380-548. (See LAXNPWLOX). Heat Advisory now in effect until 9 PM PDT this evening for zone 368. (See LAXNPWLOX). PZ, NONE.
