Random Ramblings: Aerial Wildland Firefighting

I have blogged about aerial wildland firefighting since 2009. I am not a firefighter and am not a pilot, just an interested bystander who wants to learn more and share what I learn here. Join me here as I blog on the aircraft and the pilots who fight wildland fires from the air in support of crews on the ground. I also blog on concerns affecting fire crews on the ground as well as other aviation and meteorology issues. Learn what it takes to do jobs that are staffed by the best of the best.

Monday, January 09, 2023

Atmospheric River Event in Western U.S.: January 9th Update

January 9, 2:50 PM EST

From the National Weather Service Forecast Office Los Angeles

Residents near recent burn areas are advised to monitor local weather, news, and https://t.co/qVlkZ3gRPO for up-to-date information.

Gather loved ones, pets, supplies, and important documents in the event of an Evacuation Order by local authorities.
— Ready Los Angeles County (@ReadyLACounty) January 9, 2023

#WEATHER: An evacuation warning has been issued for residents in the Lake Hughes and Kings Canyon areas due to the threat of mudflows in recent burn areas. https://t.co/u0fH9psrJm
— KCAL News (@CBSLA) January 9, 2023

Flash Flood Warning including Santa Maria CA, Santa Barbara CA and Lompoc CA until 4:45 PM PST pic.twitter.com/MeHGXYDAP2
— NWS Los Angeles (@NWSLosAngeles) January 9, 2023

January 9, 6:30 AM EST

I continue posting about the forecast atmospheric river event in California on January 9 through January 11th, see my post of January 8th where I first posted on this forecasted atmospheric event. If you are affected by the forecasted atmospheric river events or just want more information on a specific area please go the relevant NWS Weather Forecast Office for more information. Please heed any warnings and evacuation orders. Go to your local emergency management office for information on any warnings and evacuation orders that might affect you. Turn around don't drown

The Weather Prediction Center issued a short range forecast discussion on January 9th including a discussion of these forecasted atmospheric river events, I am copying the portion of the WPC discussion pertinent to California:

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Mon Jan 09 2023
Valid 12Z Mon Jan 09 2023 - 12Z Wed Jan 11 2023
...Two major episodes of heavy precipitation expected to impact California today and Tuesday...
Two major episodes of heavy rain and heavy mountain snow are expected to impact California in quick succession during the next couple of days in association with two of the more energetic and moisture-laden parade of cyclones that are aiming directly for California. The heavy precipitation episode currently streaming into central California is expected to be the more robust of the two, resulting in heavy rainfall totals of 3-5 inches near the coast. The second episode will quickly arrive on Tuesday with amounts slightly less heavy, but impacting locations farther south into southern California. The Sierra Nevada will likely see heavy snow exceeding 6 feet across the higher elevations before the snow tapers off Wednesday morning. The cumulative effect of successive heavy rainfall events will lead to additional instances of flooding. This includes rapid water rises, mudslides, and the potential for major river flooding. Susceptible terrain and areas near recent burn scars will be most at risk for debris flows and rapid runoff. For the higher terrain of the Sierra Nevada, extremely heavy snow and intense snowfall rates are anticipated to make travel very dangerous to impossible at times, including the potential for road closures. The amount of additional accumulating snow on top of an already well built snowpack is likely to increase the threat of avalanches and strain infrastructure. Gusty winds are also expected to spread onshore with the approaching system and could lead to the threat of downed trees and power outrages. The combination of saturated soil and gusty winds could exacerbate the tree damage threat. Residents and visitors across this region are advised to check their local forecast, never drive across flooded roadways (Turn Around Don't Drown!), and have both an emergency kit and evacuation plan in place.

To review, take a look at this graphic (I first posted this on December 30th) that explains what an atmospheric River on the west coast USA is.

Obtained on December 30, 2022 from https://www.noaa.gov/stories/what-are-atmospheric-rivers

One of the reasons why I started posting on the atmospheric river events is because of the risk of debris flows on recent wildfire burn scars. For more information on the danger flooding rains pose to burn scars, see my January 6th post. Two NWS Weather Service Forecast Offices, San Francisco/Monterey and Los Angeles are warning that heavy rain may lead to debris flows on recent burn scars. See the graphic images below for more information. If you live near any of these burn scars or other burn scars not mentioned, please pay special attention to any evacuation orders.

obtained on January 9, 2023, 6 AM EST from NWS Forecast Office Los Angeles

obtained on January 9, 2023, 6AM EST from NWS Forecast Office San Francisco CA

Two other National Weather Service Forecast Offices in Sacramento and Hanford/San Joaquin Valley CA are expecting heavy rainfall from this forecast atmospheric river event. See the graphic images below.