The Impacts of the El Nino Southern Oscillation, the North Atlantic Oscillation, and the Pacific-North American on Spatial Patterns of Severe Weather Occurrences

Keywords: ENSO, PNA, NAO, Severe Weather
Abstract Type: Poster Abstract

Abstract

The El Nino Southern Oscillations (ENSO), North Atlantic Oscillation (NAO), and the Pacific-North American (PNA) are known to cause a significant changes in the jet stream patterns across North America and the jet stream plays a vital role in thunderstorm and tornado development. The main research question is how do the phases of ENSO, NAO, and PNA cause shifts in the spatial distribution of severe weather occurrences across the United States. This multi-variate examination is due to the temporal aspects of severe weather patterns and the various time scales that the different circulation patterns. Data for the ENSO, PNA, and NAO phases can be easily obtained from the Climate Prediction Center website (www.cpc.noaa.gov) as they have an archived record of that information. The occurrence of severe weather in the United States is archived through the Storm Prediction Center (www.spc.noaa.gov). Each occurrence of hail, straight-line wind, and tornado will be tagged with information regarding the phase and strength of each circulation patterns. For the circulation patterns the strength will be classified into 5 categories: neutral, positive, strongly positive, negative, and strongly negative. The occurrences of severe weather was mapped based on there different categories of each circulation pattern and the various combinations of these circulation patterns.