Southern California weather is about to shift into a wetter mode. Forecasters are holding out chances of showers and thunderstorms twice over the coming 5-days. A low pressure center that’s been wandering around the Southwest will fire up the initial chance of rain tonight through Friday. The mountains are most vulnerable especially in San Bernardino County with up to an inch-and-a-half. The valleys and coastal areas will be dampened with up to one-quarter-of-an-inch. Another storm sliding down the coast should arrive by Sunday. With the clouds, higher humidity and chances of rain, temperatures are falling back to normal. October usually generates the last of the year’s triple digit days. There have been 30 days of 100-degree heat in the Riverside-San Bernardino area so far this year. Last year there were 31. The 10-year average is 31, based on official temperatures recorded by the National Weather Service.