LANDSLIDES & ENSO

Wildfires potentially increase the risk of landslides.

This is not new in the Western US. The USGS Landslide Hazards Program alerts of the danger of landslides after a rainstorm in areas of recent wildfires, explaining what to do before and during an event. This makes me think of a very probable strong El Niño event this year after all the wildfires the state has endured so far…

NOAA just prepared an updated prediction that can be seen here. Basically, they say as today El Niño conditions are present and that there is an approximately 95% chance that El Niño will continue through Northern Hemisphere winter 2015-16, gradually weakening through spring 2016.

El Niño and La Niña, together called the El Niño Southern Oscillation (ENSO), are periodic departures from expected sea surface temperatures (SSTs) in the equatorial Pacific Ocean. These warmer or cooler than normal ocean temperatures can affect weather patterns around the world by influencing high and low pressure systems, winds, and precipitation

Another good source of information is the California Geological Survey (CGS), which has produced numerous maps that show landslide features and delineate potential slope-stability problem areas.

FEMA always is also a good place to keep informed about these hazards and what to do before, during, and after.

Maps of risk areas can be downloaded and studied (regional and local examples here), which would help the managers and planners know which areas will be needing help first/more frequently.

10/17/15 UPDATE:
Flash floods sent water flowing into South CA roads.  All lanes of California's Interstate 5 reopened Friday evening after a massive mudslide pushed up to five feet of mud across the roadway Thursday, trapping cars and forcing crews to close the highway in both directions for nearly 40 miles. 

Meanwhile, State Route 58 is expected to remain closed for days after the same storm system caused flash flooding and dangerous mud flows, trapping about 200 cars there in mud as deep as 6 feet.

More information at links below:

http://www.conservation.ca.gov/cgs/information/publications/ms/documents/ms58.pdf

http://landslides.usgs.gov/hazards/

http://www.conservation.ca.gov/cgs/geologic_hazards/landslides/Pages/Index.aspx

http://www.ready.gov/landslides-debris-flow

http://www.cjpia.org/news/news-and-updates/news-and-updates/2015/10/05/strong-el-ni%C3%B1o-probable

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

http://cdfdata.fire.ca.gov/incidents/incidents_current
http://www.weather.com/news/news/california-flooding-mudslides-stranded-motorists

http://www.nytimes.com/2015/10/17/us/a-wall-of-mud-in-california-and-warnings-to-heed-el-nino.html?hp&action=click&pgtype=Homepage&module=second-column-region&region=top-news&WT.nav=top-news