Just in time for Halloween, fall temperatures are descending on the Valley, and there’s a possibility of rain showers on Thursday to dampen trick or treaters, National Weather Service meteorologist Sara Purdue said Monday.

“Nothing that’ll ruin the night per se, but definitely a chance to get sprinkled on,” she said. “If your costume is made of paper, don’t wear that.”

This week’s weather in the Fresno area will be slightly cooler than normal, with highs in the 60s and overnight lows in the mid-to-upper 40s, Purdue said.

The average for this time of year is for highs in the low 70s, she said.

The cooler weather is the result of a low-pressure system dropping down from the Gulf of Alaska into California, bringing slight chances of sprinkles — “mostly just sort of a wetting rain” — to the Fresno area Monday and then again starting Thursday and continuing through the end of the week, she said.

Wind gusts of up to 20 mph are forecast for Monday in the Fresno area, making it the best day this week for kite-flying. But the gusts are forecast to die down after Monday, Purdue said.

The forecast daytime high Monday is 67, with an overnight low of 46; 64 on Tuesday and low of 45; 67 on Wednesday and Thursday with an overnight low Wednesday of 45 and Thursday of 47; high of 65 on Friday and overnight low of 46; high of 62 on Saturday and overnight low of 45, and high next Sunday of 66.

Turn Back the Clocks, Water Just Once a Week

Sunday is the day to turn back clocks one hour, giving us extra morning daylight but making the evenings darker earlier.

And Friday will mark the change in outdoor sprinkler schedules for residents in Fresno and Clovis from three days a week to once weekly. Odd-numbered addresses may water on Saturdays only, and even-numbered addresses on Sundays only.

The once-a-week schedule remains in effect through the late fall and winter months.