*2021 Tropical Season and Summertime Outlook* — Perspecta Weather

Signals from the analog years and the summertime outlook

Based largely upon the expectation of weakening La Nina conditions later this summer and fall, there are six analog years that I have selected which featured similar sea surface temperature anomalies and trends.  When averaged together, these six analog years featured slightly above-normal tropical activity in the Atlantic Basin in terms of the number of named storms and nearly the normal amount of those that reached minimal hurricanes status and “major” classification.  The six analog years listed here include the number of named storms, number of minimal hurricanes, and the number of “major” hurricanes in each given year: 2018 (15/8/2), 2013 (13/2/0), 2011 (19/7/4), 2008 (16/8/5), 2006 (10/5/2) and 2001 (15/9/4).

In the Mid-Atlantic region, these six analog years generally featured warmer-than-normal conditions in the June through August time frame. Specifically, in terms of temperature anomalies, I expect the summer season to average from 1.0-3.0 (°F) above normal in the Mid-Atlantic region.  Elsewhere, there is reason to believe that much of the nation will experience warmer-than-normal conditions this summer based upon comparisons with these selected analog years with the south-central states potentially extremely hot (e.g., Texas).