Discussion: Red Flag Warnings are in effect for parts of Southern California as fire weather conditions reach critical levels throughout the weekend into Monday afternoon. A moderate to locally strong Santa Ana wind event has developed over the area. These winds combined with the near record temperatures in the mid 80s, low relative humidity values, and dry vegetation will bring elevated conditions to the mountains and valleys in both Los Angeles and Ventura County. Gusty winds were expected to start around 10 PM PST Saturday and are expected to last through Monday afternoon. A red flag warning is issued when the weather conditions may indicate a period of weather that could lead to extreme burning conditions. During this time, it is important to heed local burn bans, properly discard any cigarettes, and avoid activities that cause open flames or sparks. With the dry vegetation, warm temperatures, gusty winds, and low humidity it doesn’t take much to spark a wildfire!
Santa Ana winds are most often characterized as being hot/dry winds which blow in from the desert towards the coast. These winds tend to occur during the following time frame (between September and May) when the desert is cooler than the Los Angeles basin. To learn more about fire weather and fire weather education, be sure to click here!
© 2018 Meteorologist Shannon Scully
In a particularly calamitous year for natural disasters across the United States, wildfires continue to burn in California past the normal fire weather season. A new solution to arm fire weather officials, led by researchers at the University of Wyoming, hopes to model wildfire growth in an effort to close a 12-hour information gap provided by NASA's Active Fire dataset.
While the Active Fire dataset (collected from the Moderate Resolution Imaging Spectroradiometer instrument on board NASA's Aqua and Terra satellites) provides a high-resolution snapshot of the burning wildfires, it suffers temporally. According to the researchers, the more readily available that updates about the wildfire's behavior or change in growth are, the more informed fire management officials can be when making critical decisions, such as mass evacuations.
Researchers at the University of Wyoming developed a computer model to simulate fire growth and spread on the scale of minutes based on factors such as fuel moisture, land topography, and real-time weather. Preliminary results were shared with fellow scientists at the American Geophysical Union Fall Meeting in New Orleans last December.
In the results, the model was compared to NASA's Visible Infrared Imaging Radiometer Satellite data in three different wildfires that occurred in Wyoming and Montana in 2017; while the model tended to over-predict the fire area, it did predict more than 86% of the actual burning area.
According to scientists at the American Geophysical Union who attended the preliminary results session, the model looks incredibly promising. The researchers at the University of Wyoming plan to continue their investigations in an effort to improve their model by looking at the California wildfires in 2018.
Check out the full press release from the AGU here, or read more about fire weather on our site here.
© 2018 Meteorologist Chris Stubenrauch