Marine Weather and Tide Forecast for Santa Monica, CA

.SHORT TERM (TDY-FRI)...29/137 PM.

High confidence in seasonally low impact weather through Friday with relatively small day to day changes in temperatures. Some buildups have already developed across the mountains with a 10 to 20 percent chance of showers across the higher mountains, especially the Ventura County mountains today and continuing each day through Friday.

A weak trough will pass through the region Wednesday and Thursday, leading to a much deeper marine layer with low clouds pushing well into coastal valleys if not lower mountain passes during this timeframe with patchy fog and drizzle possible, especially for valleys and south facing foothills. This type of pattern will support gusty but probably sub advisory winds focused across the interior Wednesday and Thursday afternoon in particular. A reverse clearing pattern is possible Wednesday and Thursday where low clouds linger in the valleys and especially foothills longer than at the coast on those days.

.LONG TERM (SAT-TUE)...29/137 PM.

High confidence in an unseasonably strong storm to push through the region this weekend with gusty northwest to onshore winds, but low confidence in precipitation amounts (if any) and timing.
Widespread advisory level winds will be possible sometime Saturday into Sunday including many coastal areas. Where precipitation does occur it will likely be under a quarter of an inch (except up to around a half of an inch in the mountains), with the Central Coast to mountains the most favorable to receive light amounts. Snow levels will largely be between 5000-7000 feet, although may dip to around 4000 feet Saturday night into Sunday morning with light accumulations generally above 5000 feet. The unusually cold (but moisture starved) system for this time of year will support a 10 percent chance of a thunderstorm over the mountains and deserts.
Any thunderstorms that do form could be slow moving, leading to locally heavier rainfall with embedded hail or graupel. It will feel much like a mid winter storm temperature wide with highs only in the 50s to low 60s for most (10-20 degrees below normal). A late season frost is possible for the coldest interior valleys Sunday or Monday mornings. Otherwise seasonably quiet weather with rebounding temperatures is likely early next week, although there’s a 20 percent chance of some shower activity lingering into early Monday.

AVIATION
29/2102Z.

At 1659Z at KLAX, the marine layer was around 1500 feet deep. The top of the inversion was around 3200 feet with a temperature of 17 C.

High confidence in TAFs for KPRB, KWJF, and KPMD. There is a 10% chance for LIFR to IFR conds at KPRB after 10Z.

Moderate confidence in TAFs for remaining sites. South of Point Conception, most sites should see IFR conds before 10Z, then MVFR after as the Catalina Eddy strengthens overnight. For KSMX and KSBP, there is a 20 and 30% chance respectively that sites will remain IFR or greater through the period. There is a 30% chance for LIFR conds at KBUR/KVNY any point after cigs arrive before 15Z. Timing of flight cat changes could be off +/- 3 hours, but high confidence in arrival of cigs late tonight.

KLAX...Moderate confidence in TAF. Cigs may arrive as soon as 00Z or as late as 04Z. There is a 30% chance cigs remain OVC010 or greater through the period once they arrive. Otherwise, flight cat changes may be off +/- 3 hours. There is a 30% chance cigs scatter between 18Z and 00Z Wednesday. There is a 30% chance of an east wind component of 8 kt 12Z-18Z.

KBUR...Moderate confidence in TAF. There is a 30% chance of LIFR conds once cigs arrive until 15Z. Cigs may arrive as soon as 06Z or as late as 11Z.

MARINE
29/200 PM.

In the outer waters, good confidence (60% chance) that Small Craft Advisory (SCA) conds will continue much of the time thru Wed morning in the northern zone (PZZ670) and in the southern two zones (PZZ673/676) thru tonight (60% chance). There is a 30% chance that SCA conds will continue thru late tonight or early Wed for the southern two zones. SCA conds are not expected across the outer waters Wed night thru early Fri. SCA conds are likely (>80% chance) Fri afternoon thru Sun night, with a 50% chance of GALE force winds Sat afternoon/night.

In the inner waters N of Pt Sal, SCA conds are likely (50% chance) this afternoon/eve. There is a 40% chance of SCA level winds Wed afternoon/eve. SCA conds are not expected Wed night thru Fri morning. SCA conds are likely (70% chance) in the afternoon/eve hours Fri through Sun, with a 40% chance GALES Sat afternoon/eve.

In the Santa Barbara Channel, there is a 30% chance of SCA level winds in western portions during the afternoon/eve hours today and Wed. SCA conds are not expected late Wed night thru Fri morning. SCA conds are likely (70% chance) during the afternoon thru late night hours Fri through Sun, with a 40% chance of GALES across western sections Sat afternoon/eve.

In the southern inner waters, SCA conds are not expected thru Sat morning, then are likely (70% chance) beginning in the the afternoon Sat and continuing thru Sun.

LOX WATCHES/WARNINGS/ADVISORIES
CA...Beach Hazards Statement in effect through Wednesday evening for zones 362-366. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect until 9 PM PDT this evening for zone 645. (See LAXMWWLOX).
Small Craft Advisory in effect until 9 AM PDT Wednesday for zone 670. (See LAXMWWLOX).
Small Craft Advisory in effect until 3 AM PDT Wednesday for zones 673-676. (See LAXMWWLOX).