Santa Cruz Island CA to 120W between 150 and 250 NM Offshore Forecast
|Tonight...Nw Winds 10 To 20 Kt. Seas 7 To 10 Ft.|
|Wed...Nw Winds 10 To 20 Kt, Becoming 10 To 15 Kt. Seas 7 To 9 Ft.|
|Wed Night...Nw Winds 10 To 15 Kt. Seas 7 To 9 Ft.|
|Thu...Nw Winds 10 To 15 Kt, Diminishing To 5 To 10 Kt. Seas 6 To 7 Ft.|
|Thu Night...Nw Winds 10 To 15 Kt. Seas 5 To 6 Ft.|
|Fri...N To Nw Winds 10 To 15 Kt. Seas 5 To 6 Ft.|
|Fri Night...Nw Winds 15 To 20 Kt. Seas 5 To 7 Ft.|
|Sat...Nw Winds 15 To 20 Kt. Seas 6 To 7 Ft.|
|Sat Night...N To Nw Winds 15 To 25 Kt. Seas 6 To 9 Ft.|
|Sun...N Winds 10 To 20 Kt. Seas 7 To 9 Ft.|
|Sun Night...N Winds 10 To 20 Kt. Seas 6 To 8 Ft.|
| 1241 PM PDT Tue Apr 13 2021 |
Synopsis for the far southern California coast - PZZ700
At 2 PM, a 998 mb low was near Tonopah, NV. Moderate onshore flow will continue each afternoon and evening through Sunday.
| Area Forecast Discussion|
National Weather Service San Diego CA
938pm PDT Tuesday April 13 2021
A low pressure system will move into the Great Basin, strengthening the onshore flow across southern California, as well as deepening the marine layer through Wednesday with periods of stronger and gusty west winds in the mountains and deserts. There will be patchy drizzle, and even light rain along the lower coastal mountain slopes and foothills through Wednesday morning. This will be followed by a warming trend into the weekend.
FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Some patchy, light rain/drizzle was being reported along the foothills of the coastal mountains this evening, where most of the significant accumulations of one-tenth inch or more have been. The latest rainfall totals are headlined on our webpage. On the other side of the mountains, it was quite windy with some blowing dust reported in the deserts. Strong onshore surface pressure gradients of 10 MBS or more were sustaining wind gusts of 30-40 MPH in the deserts, and 50 to 60 MPH near the San Gorgonio Pass and into the northern Coachella Valley. These winds will continue through Wednesday so it looks like the Wind Advisory may need to be extended in these areas. For now it goes through the night.
The latest HRRR (High-Resolution Rapid Refresh) runs turn wetter late this evening with light showers developing in response to a weak disturbance aloft moving over SoCal. Radar indicates some very weak echoes approaching the Coast at 9:30pm which could end up producing some of this. These type of showers are always more likely overnight as saturation in the lower layers is more easily reached. This is already adequately addressed in the current forecast so no forecast changes this evening.
From previous discussion... An upper low will meander over Nevada through Wednesday evening before departing to the east. West winds to the south of this feature will strengthen tonight and be strongest on the desert side of the San Gorgonio Pass and deserts slopes to the San Diego County deserts. Peak gusts 50-60 mph are anticipated.
Clouds will continue to blanket the coast to the coastal mountain slopes. Drizzle and light showers will likely re-develop tonight through Wednesday morning. Trace to 0.05" is forecast for the coast and valleys, but the coastal mountain slopes will see 0.05-0.15". The exception may be along the mountain slopes just to the east of the Cajon Pass where 0.25-0.50" may fall. The rain will end Wednesday afternoon along with a potential return of partial sunshine especially late in the afternoon, though we may need to wait until Thursday for more sun west of the mountains. Abundant sunshine will continue at higher elevations and across the deserts.
Heigheights will rise Thursday and through the weekend. This will lead to warming conditions, rather significantly, as we move into the weekend. Warm and dry conditions will continue at the start of next week and could continue. However, uncertainty is higher as we head into the middle part of next week. Some models and their ensembles show another trough digging southward which would lead to cooling and a potential of more light rainfall. However, other members show less troughing with warm, dry conditions continuing. So confidence is high through early next week on dry and warmer weather prevailing, but lower confidence by the middle of next week.
No hazardous marine weather is expected through Sunday.
.SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions.
.SGX WATCHES/WARNINGS/ADVISORIES... CA...Wind Advisory until 5am PDT Wednesday for San Diego County Deserts-San Gorgonio Pass Near Banning.