On the Utility of In-Situ Soil Moisture Observations for Flash Drought Early Warning in the Central United States

Abstract:

Drought early warning systems are a vital component of drought monitoring, and require information at sub-monthly time scales because of the rapidly evolving nature of drought. This study evaluates the utility of in-situ soil moisture observations for drought early warning in the Central United States. Soil moisture was used to identify drought events and results were compared with the U.S. Drought Monitor with respect to the identification of drought onset. Soil moisture observations consistently identify rapid-onset (flash) drought events earlier than the U.S. Drought Monitor. Our results show that soil moisture percentiles can provide a two to three week lead-time over the U.S. Drought Monitor based on flash drought events which occurred in Oklahoma between 2000 and 2013. We conclude in-situ soil moisture observations are an important source of information for early warning of flash drought events in the Central United Staets.