National Weather Service Warnings for Flash Floods and Debris Flows Alex Tardy and Brandt Maxwell - Meteorologists National Weather Service/San Diego Building a Weather-Ready Nation
Warning Notification Flash Flood Watch – potential for FEMA alert app heavy rain exceeding thresholds today or tonight Flash Flood Warning – heavy rain is occurring or imminent and flooding is expected along with possible debris flow for “defined area” Threshold for rainfall (rate per hour) would be met and burn scar would be mentioned in Flash Flood Warning if affected Building a Weather-Ready Nation W th /S Di
TV and radio EAS alerts Wireless emergency alerts Building a Weather-Ready Nation
NWS Warning polygon Wireless Emergency Alert in polygon Building a Weather-Ready Nation
Force and depth of flash flood debris flow Building a Weather-Ready Nation
Weak El Niño Expected This Winter Both wetter and drier than normal winters have occurred in southern California with a weak El Niño. Flash flooding can occur in southern California regardless of if there is an El Niño, La Niña or neutral conditions. Building a Weather-Ready Nation
Atmospheric River BIG storms Jet Stream highest moisture in yellow and red Building a Weather-Ready Nation
Winter Storm Rainfall is widespread but localized heavy This type of “embedded rainfall” can cause high rain rates and debris flows Building a Weather-Ready Nation
https://www.wrh.noaa.gov/sgx/kml/holyfire.php Building a Weather-Ready Nation
Flash Flood Warning Debris Flow Thresholds for Holy Fire Rainfall Duration Rainfall Amount 15 minutes 0.20 inches 30 minutes 0.30 inches 60 minutes (1 hour) 0.50 inches US Geological Survey Questions? Building a Weather-Ready Nation
Recommend
More recommend
