A weak area of low pressure will stay over the area through Monday, bringing temperatures near to slightly above normal with night and morning clouds and fog for the coastal and western valley areas. A stronger area of low pressure moves by from the north, bringing cooler and breezier weather by the middle of next week.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
New Aviation and Marine Discussion,
Low clouds and areas of dense fog occurred earlier this morning in coastal San Diego County. Low clouds will move slightly further inland to all coastal regions tonight through Thursday morning as the marine layer slightly deepens as a weak trough forms over Southern California. Temperatures will be fairly similar through he weekend as the weak area of low pressure hangs around with highs near to slightly above average across the region. As the weak trough moves in, low clouds will move around 15 miles inland each night, diminishing each morning. The weak troughing pattern will bring a return to light onshore winds from the southwest and west, gusting near 15-25 MPH each afternoon and evening.
By Monday into the first half of next week, a stronger troughing pattern develops over the West Coast as an area of low pressure passes to the north. This will bring in greater low cloud coverage each night and morning across the western valleys with temperatures cooling down further where 60s and 70s will occur from the mountains to the coast. Onshore flow will increase as the low moves into the Pac NW and Great Basin by Tuesday into the middle of the week. Nbm models show winds gusting near 30-45 MPH across most mountains and deserts, with locally higher winds in the passes.
210430z, Coast, Low clouds with bases 900-1500ft MSL will slowly make their way in along the coast, beginning along southern San Diego after 05-06Z and spread northward and inland up to 10-15 miles after 08Z-09Z. Minor vis reductions of 3-6 SM will be possible along elevated coastal terrain. Low clouds scatter to the coast by 16-17z. Low clouds may linger over KSAN with intermittent BKN/SCT possible before filling in again after 02-04Z Friday.
Otherwise, predominately clear skies and VFR conditions through the TAF period.
No hazardous marine conditions are expected through Monday morning.
Ca, None. PZ, None.
