BASIC PATTERN:
Large Scale Pattern –
- The current dry pattern for California has been slow to release its dry grip on N and northcentral California. Sea surface temperature related influences (IVTinit™) are consistent in focusing the rain developments mostly west of N and Central California. Upper lows, troughs and fronts do come SE and E into California, but lack vigor.
- Precipitation trend: Mar 15, 28, 29, Apr 3, 4, 5, 9.
- March: Near normal temperatures in N California, and a turn to a bit warmer than normal in S California. Mar is currently forecasted wetter than normal in coastal Oregon, near or slightly above normal in NW California (Humboldt Co), and drier than normal from the Delta south through Central California and Monterey-San Luis Obispo Co’s. Input of moisture from clouds or showers into Central and SOCAL agricultural areas will be spotty/questionable at times through Mar.
- Below normal sea surface temperatures are suggested by the latest guidance from the North American Multi-Model Ensemble (NMME) for the period Apr – June 2022. This will tend to support risk of frost near the normal end of frost season in Apr for NW California coastal valleys, including Mendocino and Sonoma Co’s, and early April in upper Salinas Valley, and San Luis Obispo Co coastal valleys. The combination of colder than normal sea surface along the California coast (NMME climate model guidance), and well above normal temperatures in inland valleys of California, including mountains and deserts, contributes strong onshore flow and persistent marine fog. For the north and central California coast, this encourages unusually persistent or recurrent conditions for fog drip in the coastal forests during especially May and June.
FORECASTS FOR CALIFORNIA
Forecast for Northern and Central California:
NORCAL Rains: Mar 15 moderate rain N SierraNV) to about Amador Co., Other rains: Mar 19-20, 28-29, Apr 1-2, Apr 4-5, 8-10 and 12.
CENTRAL CALIF Rains: 15 (light N), 19-20, 28-29 (moderate rain), Apr 2 (light), 5, and 9-10.
WARM SPELLS: Mar 17-18, 22-25, Apr 7, 10-11 and 14-19.
COLD SPELLS: Mar 15-16, 19-21 and 28-Apr 5.
FRONTS WITH RAINS: Mar 15, 19, 28, Apr 1, 4, 8 and 12.
FROST RISK: Mar 16-18, 21-24, 30-31, Apr 3, 6-7, 11 and 13-14.
Forecast for S California:
SOCAL RAINS: Mar 19-20 (light), 28-29, Apr 2, 5 and 9 or 10.
SOCAL WARM SPELLS: Mar 16-18, 22-27, Apr 1, 6-8 and 13-20.
SOCAL COOL OR COLD SPELLS: Mar 19-21, 28-30, Apr 2-3, 5-6 and 9-11.
SOCAL FROST PERIODS: Mar 21-22, 30-Apr 1, 3-4, 6-8 and 11-12.
FRONTS WITH RAINS OR DRIZZLE: Mar 19, 28, Apr 2, 5 and 9.
Sierra Nevada:
Dates of mountain rains and snows are: Mar 15, 20-21, 29-30, Apr 2-5, and 9-12.
----------
The listing of dates normally included for hot and cold spells, and precipitation are based on our CFSDaily and CFSDailyAI forecast products, and present expected trends in precipitation and temperature (CFSDailyAI) to 4km. Our system gives some consideration of terrain and coastal influence. We consider the CFSv2 as one of the better ways to represent basic weather down in the sub-monthly time scale beyond the 15 day GFS or monthly maps from CFSv2 or NMME.
----------
Southern California Deserts Outlook for March 17 – April 17
Highlights: Turning consistently warmer than normal for most of mid April.
Looking Ahead – Long Range Outlook
Apr 17 – May 27, 2022…NORCAL and Central California: Trend toward warmer conditions in the remainder of March as upper winds shift to westerly instead of the troughing and cold N winds from the Gulf of Alaska NORCAL has experienced at times. Pleasant, warm spring conditions are indicated, with an intermix of showery periods. After this week, we should see a turn to higher snow levels than normal in the Sierras, and above normal temperatures for mid-Apr and May 2022. Near normal rainfall in the Delta and Northern California. Consistently warmer than normal in mid May onward with some hot conditions (highs in mid to upper 90s possible around May 15th and onward later in the month.
For SOCAL Apr 17 – May 27, 2022 mountains westward to coast: Mid-Apr – end of May: Progressive trend towards above normal temperature for Apr, and below normal rainfall for April (a month of usually meager rainfall). There is potential to turn hot and dry in mid-May, with foothill and coastal valley highs (avocado areas) peaking into u90s while immediate coast is cool foggy 60s to 70.
In summary, despite the possible uptick of rains in late March to early Apr in northcentral and N California, a drier than normal rainy season, overall, is likely, with some seriously low reservoir levels at the beginning of the long dry hot season. Watch for some 100+ hot spells early in the summer season for end of May and in June while cool fogs hang at the immediate coast/beach through most of the days from end of May and June.
(Terms and Definitions Used In This Weather Outlook)
Alan Fox & Zane Stephens...Fox Weather, LLC
Copyright © 2022, Fox Weather, LLC, Used by permission.