Residents and commuters across South Orange County can expect a shift to dry, windy conditions by the end of the week, as Santa Ana winds are forecast to arrive, according to the National Weather Service. This change follows a period of inclement weather stirred by the remnants of Hurricane Rachel, which recently brought rain to the Inland Empire and other areas.
The National Weather Service (NWS) explained in a statement Monday that "High pressure is going to begin to build in over the Great Basin" of Utah and Nevada, while an upper-level low becomes stalled over the Four Corners region. This atmospheric setup is expected to establish Santa Ana conditions.
Heavy clouds and sporadic rain showers lingered over the inland region Monday as the tail end of the trough associated with the tropical storm, which arrived Saturday, fully exited to the northeast. Meteorologists with the Weather Service indicated that clearing should commence by the predawn hours of Tuesday, if not sooner.
The recent storm delivered notable precipitation to inland areas. In the 48-hour period from late Saturday morning to late Monday morning, the Riverside metropolitan area recorded approximately 1.3 inches of rain, according to data from the agency.
Banning documented the highest rainfall total in Riverside County during this period, with 4.76 inches. Neighboring Beaumont was close behind, receiving 3.35 inches. Further south, Palm Springs International Airport registered 1.16 inches of precipitation, while nearby Palm Desert, in areas of rising terrain, indicated about 2 inches of rainfall. The lowest countywide measurement was at Corona Municipal Airport, where rain gauges filled with 0.64 inches.
However, the impacts of this storm are expected to quickly diminish, with forecasters predicting a return of dry, sunny weather from Wednesday through next week. The National Weather Service stated that by Friday, a strong "super-gradient jet" stream is expected to move in from the north. This system will help enhance offshore winds from Friday into Saturday.
Consequently, some coastal and inland basins could see afternoon temperatures climb as much as 15 degrees above average for Friday. This warming trend also brings a possible return of moderate heat risk for some areas. Winds are also anticipated to be rather strong and gusty, particularly in higher terrain. The agency noted that wind advisories may be issued as early as Wednesday.
From Tuesday night through early next week, the chances for precipitation are minimal. Temperature forecasts for inland areas illustrate the upcoming warming trend: In the Riverside area, high temperatures on Monday and Tuesday will peak just below 70 degrees, with lows around 50 degrees. The warming trend will begin Wednesday, with daytime temperatures rising from the upper 70s to the upper 80s as the weekend approaches, and lows settling in the low 60s.
For the Coachella Valley, highs will top out in the mid-70s on Monday and Tuesday, with lows in the upper 50s. From Wednesday to Sunday, the mercury is projected to reach the mid to upper 80s, followed by overnight temperatures in the mid to upper 60s. The Temecula Valley will experience similar highs and lows to the Riverside area on Monday and Tuesday. From Wednesday to Sunday, temperatures will range from the upper 70s to mid-80s, with nighttime lows generally near 60 degrees.
