Marine Weather and Tide Forecast for Signal Hill, CA

.SHORT TERM (TDY-WED)...14/1204 AM.

The streak of benign weather will continue through the next three days. At the upper levels a 595 dam upper high will sit atop of Srn CA today. On Tuesday a weak trof will move into the state and push the high to the south and east - hgts will fall to 590 dam.
There will only be weak flow aloft with no defining synoptic features on Wednesday - hgts will fall further to 588 dam. At the sfc strong onshore flow will continue with gradients peaking during the afternoon hours both to the east (5 to 9 mb) and to the north (4 to 6 mb).

The strong onshore flow will bring night through morning low clouds and fog will overspread the coasts and into valleys on all three days. Look for slow to minimal clearing at the west-facing beaches as well. Additionally there will be an early return of the stratus each evening. Patchy early morning drizzle is also be possible across the coasts and valleys each morning.

Max temperatures will be very similar to Sunday's, with 70s across the coasts (mid to upper 60s beaches) and 80s and lower 90s in the valleys. These max temps are mostly 3 to 6 degrees below normal for this time of year. The interior areas such as Cuyama and Antelope Valley, however, with no marine influence will continue to see max temps from 100 to 105 each day which is 5 degrees above normal. The lower heights on Tuesday will bring max temps down by 1 to 3 degrees at the coasts and 3 to 6 degrees elsewhere. Continued hgt falls on Wednesday will knock an additional 2 to 4 degree off of max temps away from the coasts.
Vly temps on Wednesday will only be in the upper 70s to mid 80s or 5 to 10 degrees blo normal.

Lastly, gusty onshore winds will continue across interior areas such as the western Antelope Valley and foothills each afternoon and evening. These winds will be near advisory levels, but only a few of the typical gusty locations will see gusts near 45 mph.

.LONG TERM (THU-SUN)...14/232 AM.

A change in the weather begins on Thursday. The upper level flow begins to switch to the SE and this will allow some moisture to advect into the area.

There is a small chance (20%) that enough upper level moisture will arrive to disrupt the marine layer, but more than likely Thursday will start out like Wednesday. There will likely be enough moisture over the area in the afternoon to produce a few mtn build ups. But there is less than a 10 percent chc of a shower or TSTM.

The GFS and EC both deterministic and ensemble means continue to show a substantial influx of moisture esp from 700mb to 850mb.
There is some mdl disagreement about how much moisture will move in in the 850mb to 700mb layer. The mdls currently indicate very little in the way of instability but that may well change as the days draw nearer and the forecast moves into sigma based mdls time frame. Currently there is a 10 percent chc of TSTMs forecast each afternoon and early evening Fri-Sun for the LA/VTA mtns and portions of the Antelope Vly.

The current forecast continues the night through morning low cloud regime, however, this might be overdone as the the moisture aloft and offshore trends could well combine to limit or even eliminate the morning stratus.

Max temps will continue to run several degrees blo normal everywhere save for the Antelope Vly which is forecast to end up a couple of degrees above normal.

AVIATION
14/0602Z.

At 0505Z at KLAX, the marine layer was 1300 ft deep. The top of the inversion was at 4100 feet with a max temperature of 24 C.

High confidence in TAFs for KWJF and KPMD.

MDT confidence in remaining TAFs. Timing of flight cat changes may be off by 90 minutes. There is a 20 percent chc of SCT conds for 1 to 2 hours in the afternoon at sites with no clearing fcst.

There is a 20% chc for cigs 002-004 at KPRB between 12Z and 16Z.

KLAX...Moderate confidence in TAF. There is a 20% chance of clearing (or brief) from 21Z to 00Z. No significant east wind component expected.

KBUR...Moderate confidence in 00Z TAF. Arrival of cigs tonight may be off +/- 2 hours. There a 30 percent chc of cigs below 005.

MARINE
13/708 PM.

Through this evening, localized Small Craft Advisory (SCA) W to NW winds may impact the waters around Point Conception south to the Channel Islands, western portions of the Santa Barbara Channel and nearshore from Point Mugu to Pacific Palisades.

Otherwise, relatively benign conditions are expected through Thursday, with the exception of patchy dense fog tonight into tomorrow morning. SCA level winds focused across the outer waters may become more widespread Friday into the weekend.

LOX WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...NONE.