Will it rain on Halloween in the Bay Area? What awaits trick-or-treaters.

Halloween trick-or-treaters in the Bay Area will be keeping an eye on the skies Thursday evening while a weather front moves through Wednesday through Thursday.

The National Weather Service said a cold front brought preliminary light showers across the North Bay Wednesday morning, but more consistent precipitation will most likely fall across the rest of the Bay Area beginning late Wednesday afternoon and into Thursday morning.

Most areas around the Bay are expected to receive only about a tenth of an inch of rain, except for the North Bay, where some elevated areas could see up to a half-inch of rain, according to the weather service.

Halloween prediction

By late Halloween morning, the cold front is expected to be well south of the Bay Area, according to the weather service, but there will be scattered showers and drizzle through the afternoon.

In its forecast briefing Wednesday, the weather service said precipitation remaining through sunset will not impact Halloween activities and trick-or-treating.

“While drizzle is expected to continue throughout the evening, particularly in the North Bay, accumulations will be light and should not impede Halloween activities,” the discussion states. “This forecaster hopes most will find that persistent drizzle adds to, rather than detracts from, the day's spooky atmosphere.”

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The temperatures are cool for ghouls

The leading edge of the cold front brought chilly temperatures to the Bay Area as early as Wednesday morning, with some inland locations dropping as low as 30°C. Below average temperatures were expected to continue into Thursday, with most locations seeing morning lows around 40°C and highs about 5 to 15 degrees below average.

For Halloween night, trick-or-treaters should add a layer to their costumes.

“Temperatures will still be cool, but not excessively cold,” CBS News Bay Area meteorologist Paul Heggen said.

More rain coming here

Forecasters expect more rainfall to occur starting Friday. A second cold front will arrive and is expected to bring widespread rain across northern and central California by Saturday afternoon. Most locations could see up to half an inch of rain from this system, up to an inch of rain in the North Bay and more than an inch of rain in the North Bay Mountains.

The weather service said gusty onshore winds were also expected, particularly over elevated terrain and over gaps and passes, where gusts of up to 30 miles per hour were possible.

Temperatures are expected to remain below average throughout the week.

The weather service said the pattern is expected to shift back to warmer and drier conditions on Sunday, with the possibility of strong development of offshore winds, raising some potential fire weather concerns early next week.