LAWTON, Okla. (TNN) -
Hurricane season is just around the corner as the beginning of summer draws near. After the active season last year, the forecast for the coming season is a particular area of interest for coastal regions. The Colorado State University Tropical Project released a forecast Thursday for this year’s season based on the conditions of March 2021. The outlook produced above-average predictions for this year’s tropical activity compared to that of the years 1981-2010, with 8 hurricanes, 17 named storms, and 4 major hurricanes predicted. A major hurricane is a Category 3 or higher ranked hurricane, with wind speeds of over 115 mph. The expected landfall probability of a major hurricane on US soil is about 130 percent of the long-period average (Klotzbach et al., 2021). The predictions laid out in the outlook are based on a method using 38 years of past hurricane data and the use of early April extended-range statistical prediction. The three different modeling types that are used by the study have all shown that the 2021 hurricane season will be of above-average activity.
Last year’s hurricane season was a record-setting period with 30 named storms, 13 hurricanes, and 6 major hurricanes. It was also the fifth costliest hurricane season on record. The season began early in the middle of May, with the final storm in mid-November. The official start of hurricane season is June 1, but after 6 consecutive years of early storm formation, the National Hurricane Center has considered a revision to mid-May. CSU predicted 16 named storms, 8 hurricanes, and 4 major hurricanes for 2020, giving it the prediction of an above-average season. NOAA’s Climate Prediction Center forecasted an above-average season for 2020 with a 60% chance for above-average tropical activity and a mere 10% for below average, proving to be consistent with the season. El Nino conditions were neutral last year, with weak La Nina conditions.
The impacts of the seasonal atmospheric changes such as El Nino and La Nina are crucial to the prediction of the Atlantic hurricane season. This season’s weak La Nina conditions along with the unlikely shift to El Nino over the summer months give a favorable environment for tropical development. The El Nino pattern is notorious for the reduction of the Atlantic hurricane season, so the neutral state of the Atlantic will trend towards tropical activity. The subtropical Atlantic conditions are also warmer than normal, a key ingredient for hurricane season.
The extended range forecast is important for a basic understanding of what the upcoming season might look like. Although the outlooks become stronger the closer it is to the middle of the season, the prominent features in the Atlantic in the early Spring can indicate what is to come. It is impossible to forecast whether or not many storms or any will make landfall in the United States, but one major landfall can lend itself to a memorable season.