21/240 AM.
A weak upper level trough will move over the area today, cooling temperatures and increasing marine layer stratus. A warming trend will begin Tuesday and peak on Wednesday, with highs 5 to 10 degrees above normal.
(tdy-Wed), 21/240 AM.
A high hgt (576 dam) will move over Srn Ca today. The lift from this low will deepen the marine to about 4000 ft and marine layer stratus will cover all of the csts and vlys. Some drizzle is possible this morning esp near the foothills. Look for slow clearing and a good chance of reverse clearing where the csts clear faster than the vlys. The deep marine layer, falling hgts and stubborn widespread clouds will bring 4 to 8 degrees of cooling to all areas. Highs today across the csts and vlys will mostly be in the 70s with a smattering of lower 80s. Most max temps will end up around 8 degrees under normal.
A small ridge will move into the area Tuesday and Wednesday. Hgts will rise to about 582 dam. More importantly there will be good offshore trends both days. This will lead to only weak onshore flow to the east and actual offshore flow from the north in the mornings. Look for a reduction in the marine layer cloud coverage as well as much earlier and complete clearing. Max temps will rise 2 to 4 locally 6 degrees on Tuesday. Due the weakened onshore flow, Wednesday will see a big 8 to 12 degree jump in temps.
Wednesday's temps should mostly end up in the 80s across the csts and in the 90s in the vlys. These max temps are 3 to 6 degrees above normal except for the Central Coast where there will be about 10 degrees over normal. There is a 20 to 25 percent chc that the forecast is not warm enough and max temps will end up high enough to warrant some heat advisories.
(Thu-Sun), 21/241 AM.
Broad troffing will likely cover the state later this week and into the weekend. The GFS does favor a ridge on Sunday but the EC, the EC-AI and many ensembles show the trof hanging on to the coast.
The onshore gradients will be fairly week through the period and there will be some weak offshore flow from the north during the mornings. This and the fact the troffing is not very sharp or dynamic will likely result in only a patchy marine layer stratus pattern.
Max temps will cool a little on most of the days, but most temps will remain a few degrees above normal. Blended ensemble guidance shows 4 to 8 degrees of cooling on Sunday, but this may be over done given the 586 fcst hgts and offshore flow from the north in the morning.
21/0940z.
At 0832Z at KLAX, the marine layer was 1900 ft deep. The top of the inversion was at 4900 ft with a temperature of 19 C.
High confidence in VFR conds for KPMD & KWJF.
Low to moderate confidence in the remaining sites. The timing of CIG and any VSBY restrictions may be off 2 hrs and flight minimums by one category. Cigs may bounce between categories. There is a 10 percent chance of -DZ through 18Z.
KLAX, Moderate confidence in TAF. Cigs may vary between 015 and 030 through 18Z. There is a 30 percent chc of no clearing. Any east wind component is expected remain less than 6kt.
KBUR, Moderate confidence in TAF. There is a 30 percent chc of BKN015 conds through 14Z.
21/241 AM.
For the outer waters, moderate confidence in the current forecast. Small Craft Advisory (SCA) level winds are likely (60-80 percent chance) for the waters around Point Conception through late tonight. There is a 40-50% chance of SCA wind gusts west and south of Point Conception Tuesday afternoon and night as well, otherwise conds will be below SCA levels through Thursday night. Expect steep, choppy seas with the SCA conditions.
For the inner waters N of Point Sal, moderate confidence in the current forecast. SCA wind gusts are possible (30-40 percent chance) during the afternoon and evening today and again Tuesday. Conds are otherwise expected to be below SCA levels through Thursday.
For the inner waters S of Point Conception, moderate to high confidence in the current forecast. Conds are expected to be below SCA levels for the most part through Thursday night. However, for the western Santa Barbara Channel, there is a 30-40% chance this afternoon/evening and Tuesday afternoon/evening.
Ca, NONE. PZ, Small Craft Advisory in effect until 3 AM PDT early this morning for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 5 AM PDT Tuesday for zone 673. (See LAXMWWLOX).
