Constructing Mimi Hughes (NOAA), Tapash Das (SIO), Dale Cox (USGS) Multi-Hazards Demonstration Project • Fire / Debris Flow 2007 Post Fire Coordination • Earthquake / Tsunami Earthquake Scenario • Winter Storm Winter Storm Scenario • Information Interface Community Interface, Implementation, Tools and Training The Great Southern California ShakeOut • A week-long series of events to inspire southern Californians to improve their earthquake resiliency; >6 million participants • Based on a scenario of a major southern San Andreas earthquake designed by the USGS for California Office of Homeland Security’s Golden Guardian exercise, Nov 2008, Oct 2009, Oct 2010, … • December 24, 1861 through Jan 21, 1862: nearly unbroken rains • Central Valley flooding over about 300 mi long, 12 – 60 mi wide • Most of LA basin reported as “generally inundated” • San Gabriel & San Diego Rivers cut new paths to sea • 420% of normal-January precipitation in Sacramento in Jan 1862 • 300% of normal-January precipitation fell in K Street Sacramento, looking east San Diego in Jan 1862 • No way of knowing how intense the rains were, but they were exceptionally large in total and prolonged. • Implication: Prolonged storm episodes are a plausible mechanism for winter-storm disaster conditions in California • Implication: A combined NorCal+SoCal extreme event is plausible. 12 days separated the flood crest in Sacramento from the crest in Los Angeles in Jan 1862 Generating the scenario details Weather Research & Forecasting (WRF) model’s nested grids Mimi Hughes, NOAA/ESRL,V at the helm From James Done, NCAR ARkStorm Precipitation Totals Daily Precipitation at three locations 6” 20” 20” Percentage of ARkStorm period spent below freezing Ratio of VIC-simulated ARkStorm Runoff vs Historical Periods (1969, 1986) Runoff Maximum Daily Runoff Total Runoff Recurrence Intervals of Maximum 3-day Runoff (relative to WY1916-2003 Historical Simulation) Summary of ARkStorm Meteorological Events Percentage of ARkStorm period spent below freezing.