Interpreting Hydroclimatic Extremes in the North American Monsoon System (Invited)

Warm season precipitation extremes in complex terrain are often controlled by a synergy of processes rather than a singular, representative, event structure. Furthermore, the processes controlling extremes in warm season precipitation may differ substantially depending on the timescale (event vs. seasonal or annual) or spatial scale (small watershed vs. sub-continental region) of the events being evaluated. Therefore a broad and inclusive understanding hydroclimatic processes must be engaged to properly understand the occurrence of warm season hydroclimatic extremes and their potential evolution in a changing climate. This talk will present an analysis of warm season precipitation extremes in the context of mechanisms operating across a range of space and timescales for the region of southwestern North America falling under the direct influence of the North American Monsoon (NAM) system. For this region, these processes may include land-falling tropical storms, organized mesoscale convective systems, synoptic scale transients and intra-seasonal oscillations emanating from the tropics. Analyses will be presented which compare regional hydroclimatic extremes to other locations in the world and which also seek to attribute common, in terms of frequency of occurrence, mechanisms responsible for significant hydroclimatic anomalies. The presentation will conclude with some thoughts on how regional climate extreme mechanisms may be influenced by a potentially warmer climate.