textproduct: Los Angeles

SYNOPSIS

16/155 PM.

A trough building into the region for the second half of this week through this weekend will continue the night through morning low clouds and fog, even pushing them further inland, and will lead to a sharp cooling of temperatures away from the coast. Temperatures are expected to warm up again next week with increasing odds of impactful heat toward the second half of next week.

LONG TERM (FRI-MON)

16/143 PM.

The end of this week through at least Saturday is set to be peak June Gloom. Broad troffing will persist over the state through the weekend and will provide the gentle lift needed for a deep marine layer. At the sfc there will be stg onshore flow to start the weekend, esp to the east. Low clouds and fog should cover the csts and all vlys and will likely xtnd into the mtn passes. The low clouds will be slow to clear and early to return. Some, perhaps many, coastal locations will see little if any clearing. Max temps will only be in the mid and upper 60s across nearshore locations with only 70s across the rest of the csts/vlys. Most max temps will end up 5 to 10 degrees blo normal.

The trof will then diminish heading into Monday and the onshore flow will subside somewhat. This will lead to a lessening of the amount of morning low clouds, esp in areas like the Santa Clarita Vly, and an earlier and more complete afternoon burn off. Look for 1 to 2 degrees of warming on Sun and 2 to 3 degrees on Monday.

Looking further ahead into the middle of next week there are good indications of a strong upper high building into the area which would lead to well above normal temps for the vlys and inland areas (continued onshore flow will moderate the heat for the csts). There are already low probabilities (10-30%) for major heat risk for the warmer inland valleys beginning Wednesday next week. The heat next week, if it comes to fruition, may pose significant impacts to residents and especially for out of towners.

AVIATION

17/0018Z.

At 23Z at KLAX, the marine layer was 1200 ft deep. The top of the inversion was near 3000 ft with a temperature of 24 Celsius.

High confidence in KPMD & KWJF in VFR and gusty southwest winds.

High confidence in ceilings at all other airports. Moderate confidence in timing (+/- 3 hours) and flight categories (+/- 500 feet ceilings).

KLAX...High confidence in IFR/MVFR ceilings for the majority of the night. Moderate confidence in timing (+/- 3 hours). No significant east wind component expected.

KBUR...Moderate confidence in IFR ceilings forming tonight with slightly stronger than usual onshore winds in the afternoon and evening hours.

MARINE

16/220 PM.

Moderate to high confidence in current forecast. Conditions are generally expected to remain below Small Craft Advisory (SCA) levels across most of coastal waters through the forecast period. Winds approach SCA levels with gusts 20 to 25 knots through this evening across the eastern Santa Barbara Channel.

Local gusts could reach 21 kts during the afternoon and evening timeframe across the western Santa Barbara Channel, Santa Monica Basin, and nearshore Los Angeles Harbor into the San Pedro Channel

BEACHES

16/220 PM.

A long period southerly swell (14 seconds and 17 seconds) will continue to affect the coastal waters through at least Friday. A Beach Hazard Statement is in effect through Wednesday evening due to elevated surf of 3 to 6 feet on south- facing beaches of Ventura County Beaches, Malibu Coast, Los Angeles County Beaches, and portions of the Southern Santa Barbara County Beaches.

Evening tides of 7.0 to 7.4 ft are predicted late this evening. The combination of the unusually high tides with elevated surf could result in minor to locally moderate coastal flooding along south exposed coasts, especially near Malibu and Long Beach. In addition, there is along potential for sneaker waves. Stay tuned for updates and refer to CFWLOX for additional details.

LOX WATCHES/WARNINGS/ADVISORIES

CA...Beach Hazards Statement in effect through late Wednesday night for zones 349-350-354-362-366. (See LAXCFWLOX). Coastal Flood Advisory in effect until 2 AM PDT Wednesday for zones 362-366. (See LAXCFWLOX). PZ...NONE.