textproduct: San Diego

SYNOPSIS

Below average temperatures will continue through Friday. Conditions will warm over the weekend, with a brief cooling trend early in the week. Conditions will warm for the middle of next week, returning to around average by next Wednesday. Night and morning low clouds and fog will reach well into the valley again tonight into Thursday, becoming shallower over the weekend.

..UPDATED AVIATION DISCUSSION

The marine layer was around 3500 ft deep this morning, with low clouds filling in the coastal basin. Visible satellite from this morning even showed low clouds through the Cajon Pass. At 11 AM, satellite was still showing patchy low clouds along the coast and portions of the western valleys. The marine layer is expected to stay a similar depth tonight, with similar inland extent expected. The marine layer will become shallower for Friday into the weekend with night and morning coastal low clouds not spreading inland past the far western valleys.

Weak troughing will gradually move east into the Great Basin by this weekend. That will result in below cooler conditions through Thursday, with a gradual warming Friday through Sunday as weak transient ridging builds over the West Coast. The warming will be most noticeable for inland locations. Even with the warming daytime highs, overnight lows will continue to cool off helping overnight relief from the heat.

Another trough of low pressure is expected to move west across Southern California Monday which will bring a few degrees of cooling and deepen the marine layer again. By the middle of next week, there starts to be some spread in the upper level pattern. NBM guidance has an 8 degree difference between the 75th (warmer end of solutions) and 25th (cooler end of solutions) percentile temperatures for the inland valleys. The current forecast follows the NBM which has temperatures within a few degrees of average for most locations.

AVIATION

170530Z...Coast/Valleys...Low clouds around 2600-3200 feet MSL will continue to fill most if not all of the coastal basin by 12Z Thursday. Bases will lift over 3000 feet MSL 14-18Z before scattering out by 17-19Z. Low clouds based around 2000-3000 feet MSL will return to KSAN and KCRQ rather early, by 23-02Z before spreading north Thursday night.

Mountains/Deserts...Mostly clear and VFR conditions through Thursday.

MARINE

No hazardous marine conditions are expected through Monday.

SKYWARN

Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions.

SGX WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...None.