Weatherwise, September has been quite an adventure for California. The month began with an incredibly long and hot late summer heatwave roasting all interior areas of the state, pushing statewide power consumption to an all-time high, and threatening electricity outages to millions. During this period of extreme heat in the midst of a persistent, severe drought, multiple wildfires broke out across California, the largest being the Mosquito Fire in nearby Placer and El Dorado counties. Then Southern California was hit by a Tropical Storm (the remnant of Hurricane Kay) where some of the driest areas of southeastern California received a year’s worth of rain (2-4 inches) in two days and an outbreak of flash floods in areas of steep slopes and near recently burned areas.

Then the low pressure remnant of Typhoon Merboka, born in the tropical region of the Western Pacific, underwent a dramatic transition and became a powerful extratropical cyclone pushing massive waves and hurricane-force winds into the western coasts of Alaska. In the process, the system induced a unusually deep, early season low pressure trough to move south to a point just west of California.

As this front advanced towards Northern California, gusty southwest winds blowing at 20-30 miles per hour ventilated the Mosquito Fire, pushing it to the northwest while producing new spot fires, particularly along ridge tops where the winds were strongest.

However, the arrival of precipitation early on this past Sunday increased humidity, lowered temperatures, and significantly sapped the vitality of the fire. With the unstable, cooler and wet conditions continuing through Monday and Tuesday, there was little new growth to the perimeter of the fire and firefighters were given an opportunity to hold and improve existing containment lines.

Yesterday, continued rain showers, along with colder temperatures kept fire activity to a minimum and the footprint of Mosquito Fire remained unchanged. Moreover, the Flash Flood Watch for the fire area expired and all evacuation orders were lifted for residents of Placer and El Dorado counties.

Nonetheless, as Operations Chief Steve Burns with California Interagency Incident Management Team 5 summed it up at yesterday morning's crew briefing: “Lots of things are still happening on this fire. We’re not done yet. We’re getting close, but there’s still a lot of work to be done.”

Specifically, fire-suppression repair work is in full swing where the fire perimeter is considered contained. And on east side, which is largely uncontained, crews are getting very close to finishing fireline construction. However, containment, currently at 49 percent, is expected to gradually but steadily increase despite warmer, drier conditions forecast for the upcoming week.