textproduct: San Diego

SYNOPSIS

High pressure aloft with weak offshore flow will bring warming through Wednesday. There will be local northeast to east winds along and below the coastal slopes of the mountains with gusts to 40 mph. Cooling will begin to spread inland on Thursday and continue into the weekend. Low pressure from the north will bring greater cooling by Sunday and Monday with high temperatures falling below average. Chances for measurable precipitation are greatest on Sunday at 35 to 45 percent, but there are wide differences on if, when, and how much precipitation might fall around Sunday and Monday.

SHORT TERM (Today through Thanksgiving)

High pressure aloft will move eastward across southern California on Wednesday, then weaken on Thanksgiving as a weak low pressure system from the west moves toward southern California and northern Baja. There will be offshore lower level flow with periods of gusty east to northeast winds along and below the coastal slopes of the mountains developing today and continuing into Thanksgiving morning with gusts mostly 40 mph or less.

High temperatures for the coast and valleys will warm 5 to locally 10 degrees today with another few degrees of warming for most areas on Wednesday. With the warming, high temperatures on Wednesday will be as much as 10 to 14 degrees above average for portions of the valleys with high temperatures ranging from the lower to mid 70s near the coast to the upper 70s to mid 80s for the valleys with the lower deserts around 80.

The weak low pressure system approaching from the west on Thanksgiving will bring mid and high clouds with cooling beginning to spread inland.

LONG TERM (Friday through Monday)

The cooling trend will continue for Friday and Saturday with high temperatures on Saturday falling to within a few degrees of average, ranging from the lower to mid 60s near the coast to the mid 60s to lower 70s in the valleys with the lower to mid 70s for the lower deserts.

Low pressure from the north will bring greater cooling for Sunday and Monday, but with greater model spread in the details. NBM chances for measurable precipitation are greatest on Sunday at 35 to 45 percent with chances for one inch or more of rainfall or liquid-equivalent in the wetter locations in the mountains around 15 to 20 percent. The snow level will fall to around 5500 feet on Monday, but with the spread between the 25th and 75th percentile increasing to around 2000 feet.

AVIATION

251600Z...Coasts...VFR very likely after through period, with less than 20% chance for CIGs this evening (highest chances after 26/05Z through 26/12Z).

Valleys/Mountains/Deserts...VFR conditions expected through tonight. E to NE winds locally gusting 25-35 kts along coastal slopes of the mtns will expand to include adjacent foothills and portions of the Inland Empire after 18Z. Areas of LLWS/low-level turbulence along foothills/west mtn slopes.

MARINE

No hazardous marine conditions are expected through most of Saturday. There is the potential for elevated winds and seas towards late Saturday or Sunday with an approaching storm system, but the forecast remains uncertain at this point; stay tuned for updates.

SGX WATCHES/WARNINGS/ADVISORIES

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