textproduct: Los Angeles

SYNOPSIS

31/715 PM.

Periods of moderate to heavy rain are expected Thursday morning into early afternoon then tapering off in the evening. Friday will mainly be dry before another system brings rain back to the area Saturday off and on into early next week.

LONG TERM (SUN-WED)

31/140 PM.

For the extended period, 12Z models indicate an extended period of wet weather for area. Models differ in the details (exact timing, amounts, etc.), but all indicate wet and unsettled weather for the area.

Through the extended period, a series of impulses will bring additional moderate to heavy rainfall to the area. At this time, the most significant impulses look to be Sunday and Sunday night then Tuesday and Tuesday night.

Based on current QPF forecasts, the Sunday through Wednesday time frame looks to be very wet. Coastal/valley areas, during this period, could receive 1.50 to 3.00 inches while foothill and mountain areas could get 3 to 6 inches of additional rainfall. One thing to note during the extended period, snow levels will likely be lower (in the 6500-7000 foot range). So, there may be some winter weather issues at the higher elevations.

AVIATION

01/0601Z.

At 0517Z at KLAX, there was no marine layer nor an inversion. There was a 7000 ft deep moist layer,

Low confidence in TAFs through 21Z. Cigs and vis will vary frequently as numerous rain showers move over the area. There is a 30 percent chc of a tstms from 13Z-19Z. Better confidence after 21Z with only a 20 percent chc of brief MVFR conds with rain.

KLAX...Low confidence in TAF through 21Z. Cig and Vis will vary frequently as the rain moves over the terminal. There is a 30 percent chc of a TSTM 15Z-19Z. Better confidence after 21Z with only a 20 percent chc of brief 4SM -SHRA BKN015 conds through 00Z. High confidence in at least a 10kt east wind component through 18Z. Wind shift back to the WSW may occur anytime 18Z-21Z.

KBUR...Low confidence in TAF through 21Z. Cig and Vis will vary frequently as the rain moves over the terminal. There is a 30 percent chc of a TSTM 15Z-19Z. Better confidence after 21Z with only a 20 percent chc of brief 4SM -SHRA BKN012 conds through 00Z.

MARINE

31/806 PM.

Moderate to strong SE winds will continue to affect the waters tonight into Thursday morning as a cold front moves toward the coast. SCA or stronger conditions will affect all areas. A Gale Warning is in effect for the Santa Barbara Channel and for the Outer Waters from the western Channel Islands north into the northern Outer Waters. The Warning is in effect through tonight.

There will likely be a lull in the winds on Thursday afternoon and evening, but there is a 70-80% chance of additional SCA level southerly winds Friday into at least this weekend, highest north and west of Point Conception as a cold front moves through the area. There is a 40-60 percent chance of GALES north and west of Point Conception Friday night into Saturday. Periods of SCA level southerly winds will continue into early next week. Rough and hazardous short period seas will be common into early next week.

Rain will likely be heaviest tonight through Thursday (New Year's Day). There is a chance of thunderstorms (best chances south of Point Conception) during this period, but confidence is low in timing. Waterspouts, gusty and erratic winds, frequent lightning, and brief heavy rain are all possible with any thunderstorm. Rain will return this weekend and continue into next week.

BEACHES

31/809 PM.

Abnormally large high tides between 6.7 and 7.5 feet MLLW will occur during the morning hours, roughly between 5 am and 11 am Thursday through Sunday. The tides could combine with southerly winds at times to bring minor tidal overflows at area beaches. While the major threat would be from pooling from water over normally dry parking lots and walkways, building surf and strong rip currents could increase the risk of minor coastal flooding.

A Beach Hazards Statement has been issued from late tonight through Sunday afternoon, but there is a 30-50% chance that a Coastal Flood Advisory and/or a High Surf Advisory could be needed over the weekend as another storm will likely generate moderate to strong winds and larger swell. While there is some uncertainty in timing of the highest surf, this would be the best chance for impacts such as shallow flooding of parking lots and roadways, some inundation of harbor walkways, and more significant beach erosion.

LOX WATCHES/WARNINGS/ADVISORIES

CA...Beach Hazards Statement in effect through Sunday afternoon for zones 87-340-346-349-350-354-362-366. (See LAXCFWLOX). Flood Watch remains in effect through Thursday evening for zones 88-349>358-362-366>382-548. (See LAXFFALOX). Wind Advisory remains in effect until 3 PM PST Thursday for zones 340>342-345>353. (See LAXNPWLOX). Wind Advisory in effect until 7 AM PST Thursday for zones 377-378. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 3 PM PST Thursday for zone 645. (See LAXMWWLOX). Gale Warning in effect until 3 AM PST Thursday for zones 650-670-673. (See LAXMWWLOX). Small Craft Advisory in effect until 9 AM PST Thursday for zones 655-676. (See LAXMWWLOX).