BASIC PATTERN:
Large Scale Pattern –
- A few light showers and thunderstorms (TSTMS) occur in SOCAL mountains and deserts around the 27-30 July, and again Aug 1 in SOCAL eastern deserts otherwise it is dry.
- During August, showers and TSTMS develop early in the month and again about midmonth, focusing on SE California deserts and in Arizona…Arizona receives rains on most of the first 10 days of August, with chance for near or a little above normal rainfall for Arizona south and east portions, and the Mogollon plateau area.
- We continue in the middle of the midsummer heat and fire season in mountain areas of central and N California and hot weather for the rest of the state through 31 July. During 1-4 August troughing returns to N and central California, with much cooler weather, and a chance for mountain showers and TSTMS central Sierras and in NW California mountains.
- Looking to the fall, the best chance for normal rainfall in California will be in far NW coast area, and in coastal Oregon during October. November now appears to be drier than normal throughout California. December currently appears to be drier than normal in central and N California, but possibly wetter than normal in SOCAL. Warmer than normal conditions are currently indicated through the Fall from September through December for central and N California.
- Precipitation Trend - Some mostly dry thunderstorms (TSTMS) with dry lightning occur central Sierras 28th, then some desert thunderstorms 29-31 July and 1-6 Aug in SE California desert areas. Other TSTMS occur on 15-16th in the Sierras, and again 19-20 Aug.
FORECASTS FOR CALIFORNIA
Forecast for Northern and Central California:
NORCAL Rains: Dry TSTMS Sierra east slope Aug 2-6. Showers Sierras Aug 15-16, Few mountain showers 16-17, 22-24 and 27-30.
CENTRAL CALIF: Dry thru Aug 11. Aug 12-13 few mountain showers, 15-17 scattered showers in Sierras, Aug 21-24 and Aug 26-30.
WARM SPELLS: Jul 30-31, Aug 6-14, 18-22 and 25-28.
COOL SPELLS: Aug 1-4.
Forecast for S California:
SOCAL RAINS: Jul 29-31 (E mountains), 1-3 (deserts & E mtns), Aug 7-12, Aug 17-20, Aug 25-29.
SOCAL WARM AND HOT SPELLS: Jul 29-31, Aug 6-16 and 21-24.
SOCAL COOL OR COLD SPELLS: Aug 3-5.
Forecast for Central Sierra Nevada:
Dates of mountain showers of rain: Jul 30, Aug 2-4, 10-12, 18-20 and 24-29.
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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.
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Southern California Deserts Outlook for July 30 – August 30, 2022
Highlights: Hot weather alternates with usual monsoonal TSTM conditions during August.
Looking Ahead – Long Range Outlook
September 1 – October 31... NORCAL and Central California coastal valleys, and Central Valley: Warmer than normal in Sept, with some hot conditions (highs in the mid-90s to near 100 in the hot spells. Near normal precipitation in the Sierras and Siskiyou Mountains, and Trinity Co-north along the coast range with a few showery periods. Inland valleys (Sacramento and San Joaquin Valley systems remain drier than normal through Sept. October turns wetter than normal along the coast from Sonoma Co north, but temperatures are still above normal due to hot spells during the intervening dry periods. Otherwise above normal temperatures are expected to continue throughout central California due to dry downslope wind events with basically unbroken dryness south of the Bay Area.
For SOCAL mountains westward to coast: Above normal temperature. There is potential to continue hot and dry. Foothill and coastal valley highs m90s (avocado areas), but intermediate valleys persistently into the m90s to over 100 on occasion. Tropical cyclone-associated moisture increases around the first week of September, and again about mid-September in the mountains and deserts of SOCAL. At least a seasonably hot September is suggested by the current update of the CFSv2 model. There may be some more coastal cooling with eddy conditions becoming more dominant for a time at the SOCAL coast mid-September.
(Terms and Definitions Used In This Weather Outlook)
Alan Fox & Zane Stephens...Fox Weather, LLC
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