Marine Weather and Tide Forecast for Imperial Beach, CA

DISCUSSION
FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES...

Evening update...
No hint of marine layer low clouds or fog this evening with scattered high clouds moving up from the southwest. Surface pressure gradients are trending stronger offshore after weakening during the afternoon. As a result, winds have strengthened again with gusts of 25-40 mph below the passes and on the coastal foothills. Breezy conditions will continue overnight, diminishing Sunday morning with a sea breeze taking over Sunday afternoon. No changes to the forecast this evening.

Previous discussion...
Temperatures will remain well above average this weekend with highs reaching into the 80s for valleys west of the mountains into the lower deserts, while 50s/60s remain over the higher elevations.

As the upper level high begins to weaken Sunday into Monday, subtle cooling will occur for areas near the coast with highs around 5 degrees cooler, while still remaining warm inland where highs will reach into the 80s for valleys west of the mountains into the lower deserts, while 50s/60s remain over the higher elevations. The marine layer will begin to rebuild, which will lead to a better chance of fog near the coast by Monday morning, some of which could be dense for the morning commute. A weak impulse of offshore winds may occur on Tuesday, with more elevated wind gusts near 30 MPH at times in the passes. Confidence is low if this will keep the completely offshore, so confidence remains low on any development at the coast.

High pressure will remain over the region through the middle of next week, though weaker. An area of low pressure will move closer to the region by this time, aiding in greater onshore flow and a slow cooling trend. This will bring a few degrees of cooling each day into Friday, where highs will mainly be in the 60s or lower 70s for all lower elevations. Models continue to struggle on exactly where this area of low pressure will go, though a general trend toward a more zonal pattern is indicated.
Ensemble members do show greater chances for wet weather sometime by next Friday or next weekend. Rain chances for now remain near or below 20 percent with low confidence on when or if we see any rainfall from this weather system.

AVIATION
180315Z...SCT high clouds and VFR conditions prevail region-wide through Sunday night. Offshore N/E winds gusting to 30-35 kts over mountain slopes and on the lee side of the Banning and Cajon Passes are coming down tonight, diminishing below 30 kts almost everywhere by 08z. Isolated patches of dense fog are possible along the immediate coast 06-10Z Sun, but are unlikely (10% chance or less) to impact any TAF sites.

MARINE
Tonight, low probability (less than 10%) for any impactful fog formation. Fog chances increase slightly Sunday night into Monday and again Monday night into Tuesday. Patchy fog can result in visibility dropping locally below 1 nautical mile. Otherwise, no hazardous marine conditions are expected through Wednesday.

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



SGX WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...None.