Rim Fire California's 7th Largest on Record, and is 23% Contained

California's massive Rim Fire in Yosemite National Park continues to grow, but firefighters took advantage of less windy conditions on Tuesday and had attained 23% containment of the fire as of 9:20 am EDT on Wednesday. According to Inciweb, the Rim Fire has burned 187,000 acres. This ranks as the 7th largest fire in state history, and largest fire on record in the California Sierra Mountains, says wunderground's weather historian, Christopher C. Burt in his latest post, "The Worst Wild Fires in U.S. History". The Rim Fire will likely climb to be the 5th biggest fire in California's history by this weekend, but will have difficultly surpassing California's largest fire on record--the Cedar Fire in San Diego County of October 2003. That fire burned 273,246 acres (430 square miles), destroyed 2,820 buildings, and killed 15 people. California has had its driest year-to-date period, so it is no surprise that the state is experiencing an unusually large fire this summer. It would also not be a surprise if the state sees another huge fire this year, as peak California fire activity usually comes in September and October, during the end of the six month-long dry season, and when the hot, dry Santa Ana winds tend to blow.


Figure 1. California's Rim Fire as captured by a member of the International Space Station on August 26, 2013. Lake Tahoe is visible at the top, and smoke from the fire obscures the northern portion of Yosemite National Park, and streams into Nevada. Image credit: NASA.


Figure 2. Outbuilding and pickup truck burned by the Rim Fire. Image credit: USFS-Mike McMillan

Weather conditions over the next five days where the Rim Fire is burning are expected to near average, with high temperatures in the upper 80s to low 90s and moderate winds. Air quality alerts for smoke have been posted over portions of California and Nevada, and Reno, Nevada is under a dense smoke advisory. The dense smoke will result in unhealthy air quality in the city, and prolonged outdoor activities are being discouraged. Travel may be difficult due to reduced visibility less than five miles on some area highways.

Links to follow
Wunderground's weather historian, Christopher C. Burt's latest post, "The Worst Wild Fires in U.S. History".
Our wundermap with the fire layer turned on is a good way to track the fire perimeter and smoke plume.
Crane Flat webcam
Time lapse of the Crane Flat webcam for 8 hours on Tuesday.
Yosemite Fire Example of How Droughts Amplify Wildfires, August 26 post by Andrew Freedman of climatecentral.org

Tropical wave midway between Africa and the Lesser Antilles downgraded
A tropical wave that came off the coast of Africa on Sunday is midway between Africa and the Lesser Antilles Islands. This disturbance is moving westward at 10 - 15 mph, has a modest amount of spin, but has lost nearly all of the limited heavy thunderstorm activity it had. In their 8 am EDT Wednesday Tropical Weather Outlook, NHC downgraded the 5-day odds of formation of this disturbance from 30% to 20%. Wind shear is a moderate 10 knots over the system, but there is an area of dry air and dust from the Saharan Air Layer (SAL) to the north that is interfering with development. For the next few days, though, the wave will experience upward-moving air from a Convectively-Coupled Kelvin Wave (CCKW) that is moving eastwards across the Atlantic at 25 - 35 mph. This interaction may contribute to development. With the exception of the NAVGEM model, there is little support from the models for developing the disturbance during the next five days. The wave could spread heavy rains and gusty winds to the Lesser Antilles Islands as early as Sunday.

A tropical wave expected to emerge from the coast of Africa on Friday and track over the Cape Verde Islands is developed by the GFS and European models. This wave is expected to take a northwesterly track, and would likely not be able to make the long trek across the Atlantic to threaten North America or the Caribbean Islands.

Jeff Masters