World Series victory parade goers, Bay Area trick-or-treaters and Halloween revelers should think about adding an umbrella to their costumes this Friday as a storm system makes its way through the Bay Area.
The NBC Bay Area Microclimate Weather Team says rain is likely throughout the Bay Area during the day Friday and on Halloween night.
A cold front heading south from the Gulf of Alaska should reach the North Bay by early Friday Morning, and slowly make its way south, creating a wet commute, especially for San Francisco and points north. The South Bay should see showers during the morning.
The wettest weather will likely occur between 8 a.m. and 2 p.m. throughout the region. There may be a brief break in the rain during the late afternoon before more evening showers.
The North Bay and Santa Cruz mountains will likely see the most rainfall, with totals of more than 1.5 inches possible. Most spots will likely see more than a half-inch of rain.
Thunderstorms are most likely during the late evening hours on Friday and into the early morning on Saturday, especially in the North Bay, where a short wave trough will pass through. Rainfall rates during thunderstorms could exceed an inch per hour. There is a low chance for lightning elsewhere in the Bay Area.
Halloween isn’t often rainy in the Bay area. According to National Weather Service records, it rains only about 1/8 of the time. However, during our drought, we’ll take rain any time we can get it. Be forewarned…you should expect a chilly and damp Halloween.