Last Friday’s system had a wintry flavor with steady showers in parts of the Bay Area and a fresh blanket of snow from the Sierra. We may not be well on our way to winter yet.

A few wind events will dry out Northern California and increase the risk of fires.

Parts of the Bay Area saw some good soaking last week. Why is the risk of fire still a concern?

Last Friday’s storm was very powerful and produced more than an inch of rain in parts of the North Bay. Some areas of the South Bay did not receive measurable precipitation.

While the increased humidity is helpful, the upcoming pattern will dry out the “fuels” over the coming week.

Until the Bay Area receives significant rain, our fire season continues.

Were there any major fires in November?

High winds caused the Camp Fire in Butte County to explode on November 8, 2018. The fire front moved quickly at a rate of 80 football fields per minute.

This fire has the grim distinction of being the deadliest fire in California history. The Camp Fire burned 153,000 acres and killed 85 people.

What is the weather situation that produces these strong winds?

When forecasting in the fall, it is the higher level weather pattern that meteorologists look for –

First – A storm is developing to our north. Instead of moving to Northern California, it takes an inland route to the east.

Second, an upper-level high pressure system is forming in the Pacific.

The pressure difference between these two systems produces a northerly wind. When these systems intensify, strong winds blow over land and bring dry air.

The moist earth flow to which we are accustomed is suspended. The combination of dry air, gusty winds and low vegetation moisture still makes wildfires a threat. We are still at the height of fire season.

The strength and proximity of different pressure systems dictate the strength of the winds.

What should you watch out for this week?

We follow two main wind events.

Sunday: The first wind event develops. The risk of fire will be high. The northerly winds will strengthen. Gusts could range between 30 and 45 mph. Recent precipitation has been beneficial and is not expected to cause an extreme fire risk.

Wednesday: the second wind event begins (perhaps as early as Tuesday evening). Although some uncertainty remains over forecast details, this event could be larger.

Gusts could possibly range between 40 and 65 mph.

Since the fuels have had a chance to dry, the conditions could lead to a more critical situation. Red flag warnings could potentially be issued for parts of the Bay Area.