The bottom map shows the difference in total watch days between the strongest El Niño months and the strongest La Niña months. The middle map shows the total watch days for the ten Januarys with most pronounced La Niña conditions during December-January. The top map shows the total watch days in the ten Januarys corresponding to the most pronounced El Niño conditions during December-January. (*Divide grid cell numbers by 10 to arrive at monthly mean watch days in each phase). The years with the 10 warmest (El Niño) and 10 coldest (La Niña) phases for the December to January time frame, back to 1970, were used to select the total* January watch days within each phase.

The ENSO phase strength was ranked using the Multivariate ENSO Index, or MEI. With strong El Niño (ENSO warm phase) conditions continuing into the winter months, here's an analysis of how those conditions may influence the number of watch days in December.

This page has charts of the latest preliminary severe storm reports, annual summaries, and links to comma-separated-value (csv) data files from the SPC severe weather database back to 1950.Ī map of all tornado (red), hail (green), and thunderstorm wind gust (blue) reports from NWS offices in 2022.Ĭool Season Watch Days and El Niño Southern Oscillation (ENSO) Phase SPC AWIPS Products | Data | Tropical Cyclone Tornadoes | SVR GIS Watch Frequency Maps | 20y Annual Average Watches by County | 30-year Severe Climatology Monthly Tornadoes Since 1950 | Bi-monthly Tornadoes by ENSO Phase Strength Annual Tornado Maps | 2023 Preliminary Reports to Date Severe Weather Maps, Graphics, and Data Page

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