07/111 PM.
Temperatures today will be either below or near normal, followed by a noticeable warming trend starting Tuesday. The heat spell will peak on Wednesday and Thursday, with many areas 5 to 10 degrees above normal. Some cooling is expected by the weekend, followed by another warming trend early next week.
(tdy-Thu), 07/154 PM.
Temperatures were several degrees cooler today as the upper low over northern California drifted slightly farther south and onshore flow increased. However, big changes coming tomorrow and the remainder of the week as high pressure over Arizona expands west into southern California. Weakening onshore flow and subsidence aloft from the strengthening high pressure system will squash the marine layer to under 1000 feet by Wednesday and bring significant warming to inland areas and minor warming to coastal areas. Valley highs expected to be in the mid 90s to around 103, but with a 20-30% chance of 106 in Woodland hills. Coastal areas more than 10 miles inland in the 80s to around 90. And far interior areas 100-106 with a 20 percent chance of reaching 108. Overall highs will be 5-10 degrees above normal.
Areas north of Pt Conception will warm up a little more slowly due to the closer proximity of the upper low but by Thursday inland highs are expected to reach 100 or slightly higher.
Based on the current forecast highs are still mostly below heat advisory criteria, partly due to relatively cool overnight temperatures in the low to mid 60s which will provide several hours of relief. Still, people should avoid any strenuous outdoor activities during the afternoon and stay hydrated. Will revisit the possibilty of heat headlines Tuesday based on the latest guidance and trends.
Some gusty and hot Sundowner winds are expected across southwest Santa Barbara County Wednesday and Thursday evenings.
(Fri-Mon), 07/204 PM.
High pressure is expected to weaken slightly Friday into the weekend, resulting in an increase in onshore flow and cooler temperatures. It will still be warm but highs will much closer to normal levels for this time of year.
Going into next week models are still advertising building high pressure again, and possibly even stronger than this week. However, models are also showing a very strong onshore flow during that period, around 10mb to the east and 5-7mb to the north based on the 12z GFS. If this holds the onshore flow will likely keep temperatures near to slightly below normal for coast and valleys and slightly above normal for interior areas, but with the added gusty onshore wind factor that could increase the risk of fire activity.
08/0156z.
At 23Z near KLAX, the marine layer was 1500 ft deep. The top of the inversion was 3400 feet with a temperature of 25 C.
High confidence in VFR TAFs for KWJF and KPMD.
Overall, moderate to low confidence in remaining TAFs. Timing of CIG/VSBY restrictions may be off by 2 hours for KSBP/KSMX and 3 hours for other airfields. There is a 40% chance of IFR CIGs at KLGB. There is a 10% chance of LIFR cigs arriving from 10Z to 16Z Tue at KBUR/KVNY.
KLAX, Moderate confidence in 00Z TAF. There is a 10% chance of LIFR CIGs ~004 10Z to 16Z Tue. Lowest confidence in timing of CIGs returning (+/- 3 hrs). No significant east wind component expected.
KBUR, Moderate confidence in 00Z TAF. There is a 10% chance of LIFR cigs arriving from 10Z to 16Z Tue. Otherwise, VFR conditions are expected.
07/236 PM.
Small Craft Advisory (SCA) level winds are likely across the waters around Point Conception and the Northern Channel Islands late this afternoon and evening (Moderate confidence). Better chances on Tuesday. High confidence in SCA level winds expanding across the rest of the Outer Waters and moderate confidence for the Inner Waters along the Central Coast Wednesday through Thursday. Seas are likely to remain below SCA thresholds through the period.
Inside the southern California bight, moderate confidence in SCA level winds in the western and southern portions of the Santa Barbara Channel this evening with local SCA level wind gusts in the eastern portion as well as near Point Dume, and into the San Pedro Channel. High confidence in widespread SCA level winds across the Channel and the Inner Waters off the LA and OC coasts including nearshore on Tuesday. Chances for SCA winds back off Wednesday and Thursday, but remain moderate for the western and southern portions of the Santa Barbara Channel along with local gusts near Point Dume, and into the San Pedro Channel. Choppy, short period seas will be common Tuesday.
Patchy dense fog may affect the coastal waters overnight and in the morning hours through the period, with best chances in the waters off the Central Coast.
Ca, NONE. PZ, Small Craft Advisory in effect until midnight PDT tonight for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Tuesday for zones 673-676. (See LAXMWWLOX).
