October will have an unpredictable start as Rosa and front merge

Forecast precipitation amounts Tues pm thru Weds. Courtesy:NWS San Diego

An unusual weather event for the early part of fall kick off the rainy season early as the month of October will start out as a wet one.

Moisture from the remnants of Hurricane Rosa that is currently approaching the tip of the Baja California coast and an upper level low swinging in from the Pacific will combine bringing several days of showers and an unstable atmosphere will bring some areas heavy downpours and possible thunderstorms.

The area could see as much as an inch of moisture before the system clears put by Thursday morning.

There is a small chance late Monday for some that one of the outer bands of Rosa might produce a shower which forecasters are calling a 20% chance.  Most, if not all of the precipitation will not fall until the surface front coming in off the Pacific begins to move through on Tuesday with the main event occurring Tuesday evening and into Wednesday.

There will be a 40 percent chance of showers during the day on Tuesday, then 60 percent Tuesday night and through Wednesday.

Forecaster state that the longer it stays sunny on Monday the more unstable the air will become and the chance of thunderstorms rises.  A high of 88 is forecast on Monday as the upper level clouds from Rosa will begin to arrive.