Average September weather will demonstrate across the deserts this weekend, with lots of sun and dry weather.
High temps will be 100-108 this weekend, with lows mostly in the upper 60's and 70's.... very close to normal. Dewpoints should remain well below 55 degrees.
An offshore wind event is possible over the weekend, with east to northeast winds driving humidity value way down to under 10% at times. Winds will mostly be confined to our west, blowing up to 30 mph at times in the Inland Empire, especially near Banning, and below the Cajon Pass. There is a slight chance of gusty winds in our area as well, but mostly 25 mph or less, and most likely along the highway 62 corridor and along I-10 from Whitewater to Beaumont.
An upper level low pressure is slowly developing off our coast, and will move south and become stationary Monday and Tuesday off the coast of Northern Baja California. This low is what will be responsible for the offshore wind pattern... and is eventually expected to tap moist air from south of us in Mexico by Monday.
As the moisture starts heading north, and combines with the atmospheric dynamics of the low pressure system, clouds will begin to increase on Monday, with a slight chance of scattered showers or thunderstorms during the day Monday. Mostly dry thunderstorms are a possibility, with dry lightning being a hazard for wildfire production on Monday.
By Monday night, more moisture moving north into our area will increase the probability of showers, with slightly increasing humidity expected. Tuesday and perhaps Tuesday night appear to be when we have the highest probability for storms. Early precipitation totals are expected to vary, due to the scattered nature of this type of storm. At this point, up to 0.50 inch is expected to fall in some areas. This will likely be changed a bit as we get closer to Monday and the forecast models get a better handle on the forecast.
Temps may cool back into the 90's for Monday-Wednesday, before warming up again later next week.
More details as the weekend transpires!