Bay Area Gets Break From Drought, Heat Dome, Mosquito Fire as Work Week Ends: Forecast Says Hurricane Kay Thunderstorms

As the work week comes to an end, the Bay Area and the rest of California get a breather from the drought, heat dome, and mosquito fire. Experts predict that Hurricane Kay's remnants could bring thunderstorms.

The Bay Area and the rest of the state will experience the long-awaited cooling trend on Friday, with temperatures dropping through the weekend. The Sierra Nevada is also expected to experience a steady decline in temperature, which is excellent news for the firefighters facing the Mosquito Fire.

This fire, which is raging in the Tahoe National Forest as well as the counties of Placer and El Dorado, has grown considerably since it first started. That is attributable to this week's statewide heat wave-induced intensely hot and dry weather. And according to weather models, a rare system will likely fan so much the wildfire this weekend.

Much-Awaited Rain from Kay

Areas Nearby Southern California are in the middle of a dramatic Areas close to Southern California are experiencing a dramatic change from this week's widespread heat wave as tropical storm-force winds rip through the San Diego-Tijuana metro area, churning choppy waters off the Southern coasts of California. This weekend, Southern California is expected to receive up to 4 inches of rain, with even higher totals potentially along the San Bernardino and San Jacinto ranges, thanks to Kay, which is currently riling up the coast and pushing historic rains to much of Baja California.

The Canadian, European, and American weather data models predict that the Bay Area and Sacramento will be able to take advantage of some of this leftover tropical moisture.

To help fill the hole left by this week's heat dome, southerly winds will lift Kay's leftover moisture northward. By Sunday, this will cause precipitable water values, which gauge the amount of water vapor in the atmosphere, to rise up to 100% above average in Northern California.

And Also... Thunderstorms

Due in large part to the heat dome being directly over Central California for over a week, the air in the Bay Area and Central Valley is still extremely dry. Due to a phenomenon known as virga, a significant portion of the moisture that is expected to arrive this weekend despite the fact that it is moving in may just evaporate before it reaches the ground.

This is bad news for the firefighters battling the Mosquito fire. The firefighters may have to contend with strong isolated gusts this weekend in addition to any Kay-related prevailing winds near Tahoe.

On this fire, there has already been intense fire activity, and on Thursday, at least two pyrocumulonimbus clouds erupted. The winds from this hurricane's remnants will not only fan the Mosquito Fire, but they will also blow smoke into the Sacramento Valley. This implies that much of the state will experience muggy and hazy weather this weekend.

For Friday, the Bay Area Air District has posted a warning to take into account haze for the remainder of the weekend. Even for those who are fit and healthy, as AQI levels in Tahoe exceed 300 from Friday through Sunday, it will be extremely risky to breathe in.

However, any virga in the area has a low likelihood of developing into dry thunderstorms. The remnants of Kay will also be carrying unstable air into the area. As of Friday, model runs indicate there is a less than 5% chance of dry thunderstorms occurring in Northern California, the Bay Area, or the Central Coast, San Francisco Chronicle reports.