04/1259 AM.
Onshore flow will continue to bring low clouds to the coasts and coastal valleys each night through morning. The onshore flow will start to weaken Monday and cause decreasing clouds in the valleys and gradually warming temperatures. Expect a return to near normal temperatures by early next week, with potential for above normal temperatures by mid- week.
(tdy-Mon), 04/1253 AM.
Generally quiet weather is expected through the weekend for the most part, with temperatures remaining fairly stable. There will be a few degrees of warming on Saturday followed by slight cooling on Sunday. Starting Monday there will be a warming trend, initially to near normal temperature but with above normal highs likely by midweek. Winds will be mainly weak, except for onshore winds in the afternoon to evening hours, strongest through the passes and canyons of LA County into the Antelope Valley. On Monday northerly gradients along the Central Coast will result in Sundowner winds developing in the late afternoon and overnight hours, at this time looking to remain below Advisory levels.
The marine layer was somewhat shallower last night into this morning, with low clouds much more limited than previous nights. Expect a similar cloud pattern tonight into early Saturday under weakening onshore flow and slightly higher heights aloft. Most coastal areas will see low clouds overnight, spreading into some of the coastal valleys but not affecting the interior valleys. Decreasing marine layer clouds are then expected through the remainder of the short term and into the coming week.
High clouds will spread across the area tomorrow along with some increasing mid- level moisture. A weak impulse aloft will approach Point Conception from the south late Saturday afternoon with a low (around 10 percent) chance of convective storms developing. As low levels remain quite dry, there is also a low risk of dry lightning associated with this feature. The convective chances will persist through late Saturday evening.
(Tue-Fri), 04/1254 AM.
High pressure aloft across the four corners area early next week will expand westward over southern California, with a significant warming trend on tap for the region. 500 mb heights aloft will rise to 591 mb Tuesday, peaking at 594 mb Wednesday into Thursday before decreasing some on Friday. Above normal temperatures are expected during this time, with valley highs in the mid to upper 90s possible and low 100s over the Antelope Valley. The interior coastal areas could see highs in the mid to upper 80s, with marine layer influence limited to near- coastal areas. Overnight lows will be warm as well, particularly over the foothills and mountain slopes, adding to the potential heat stress.
While slight cooling is possible on Friday, temperatures could remain above normal through the weekend and into the following week. CPC outlooks continue to favor above normal temperatures through at least week 2. Finally, an increased pressure gradient Tuesday through Thursday will result in a return to modest sundowner winds Tuesday and Wednesday nights.
04/0648z.
At 0532Z at KLAX, the marine layer was 1200 ft deep. The top of the inversion was 1900 feet with a temperature of 23 C.
High confidence in KWJF and KPMD TAFs.
Low to moderate confidence in remainder of TAFs. Timing of flight cat changes may be off by +/-2 hours. KPRB may remain VFR through the period. There is a 40% chance that cigs only lower to IFR levels through the period.
KLAX, Moderate confidence in TAF. Timing of flight cat changes could be off by +/- 2 hours. There is a 20% chance of BKN004 conds 10Z-15Z Sat. No significant easterly wind component is expected.
KBUR, Moderate confidence in TAF. Timing of flight cat changes could be off by +/- 2 hours. There is a 40% chance that cigs only lower to BKN005-008 levels overnight.
04/156 AM.
For the Outer Waters, moderate to high confidence remains for the current forecast. High confidence in winds and seas remaining below Small Craft Advisory (SCA) levels through Sunday morning. For Sunday afternoon through Thursday, there is a 50-80% chance of SCA level winds. Seas will begin gradually increasing Sunday and will reach advisory levels mid-week.
For the Inner Water north of Point Sal, moderate to high confidence in current forecast. Through Monday morning, winds and seas are expected to remain below SCA levels. There is a 30% chance of SCA level winds on Monday and a 60% chance Tuesday & Wednesday. Seas will begin gradually increasing Sunday and will near advisory levels mid-week.
For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. Through Tuesday, high confidence in winds and seas remaining below SCA levels for most of the southern Inner Waters. The only exception will be the western half of the Santa Barbara Channel, where there is a 50-80% chance of SCA level winds Sunday through Wednesday, during the late afternoon and evening hours.
Ca, NONE. PZ, NONE.
