textproduct: Los Angeles

SYNOPSIS

21/825 PM.

A shallower marine layer is expected over the next few days and a significant warming trend will start Monday, peaking around Wednesday with well above normal afternoon temperatures. A push of moisture midweek will bring at least a low chance for rain and then drier conditions return. Temperatures are expected to cool heading into the end of the week and the weekend.

LONG TERM (THU-SUN)

22/148 AM.

For the extended period, models continue to exhibit good synoptic agreement. At upper levels, trough will sag across the state with cyclonic flow over the area through the weekend. At the surface, moderate onshore flow will continue with some enhancement of northerly offshore gradients next weekend.

Forecast-wise, no dramatic changes to current forecast thinking. On Thursday, the heat will have one last hurrah across the area, although it will be a couple degrees cooler than Wednesday. So, HEAT ADVISORIES for LA county will remain in effect through Thursday evening.

For Friday through Sunday, the cyclonic flow aloft will usher in a cooling trend for all areas with lowering thicknesses and increased areal coverage of marine layer stratus. Typical onshore winds will continue across interior sections each afternoon and evening. However, with the increase in northerly offshore gradients, there will be an increase in northerly winds across the Santa Ynez Range and the I-5 Corridor. Winds across the western half of the Santa Ynez Range could approach advisory levels next weekend.

AVIATION

22/0413Z.

At 0400Z at KLAX, the marine layer was around 1200 feet deep. The top of the inversion was 5100 feet with a temperature of 18 degrees Celsius.

For the 06Z TAF package, high confidence in KPMD and KWJF.

For all other sites, low to moderate confidence in 06Z TAFs. Timing of flight category changes could be +/- 3 hours of current forecasts. CIG categories could be either MVFR or IFR.

KLAX...Moderate confidence in 06Z TAF. Timing of flight category changes could be +/- 3 hours of current forecasts. There is a 50% chance that CIGs will not drop to IFR levels overnight. No significant easterly wind component is expected.

KBUR...Moderate confidence in 06Z TAF. There is a 50% chance that MVFR VSBYs do not develop overnight. There is a 30% chance of IFR CIGs in the 11Z-17Z time frame.

MARINE

22/147 AM.

For the Outer Waters, moderate to high confidence in current forecast. Today through Wednesday, high confidence in winds and seas remaining below Small Craft Advisory (SCA) levels. For Thursday through Friday, there is a 40-60% chance of SCA level winds developing.

For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. Today through Thursday, high confidence in winds and seas remaining below SCA levels. On Friday, there is a 50-60% chance of SCA level winds in the afternoon and evening hours.

For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. For a majority of the southern Inner Waters, high confidence in winds and seas remaining below SCA levels today through Friday. However, for the western half of the Santa Barbara Channel, there is a 50% chance of SCA level winds on Friday in the late afternoon and evening hours.

LOX WATCHES/WARNINGS/ADVISORIES

CA...Heat Advisory remains in effect from 8 AM Tuesday to 9 PM PDT Thursday for zones 88-368-372-373-379-380-548. (See LAXNPWLOX). PZ...NONE.