The 2021 hurricane season may have ended just over a week ago, but Colorado State University is already looking ahead to the 2022 season.
The 2021 season was very active with 21 named storms, running out of names for the second year in a row. Despite the number of names being above normal, the season was relatively average in the number of hurricanes (7) and the number of major hurricanes (4).
Their 2022 outlook is based on probability scenarios for a weather index called, Accumulated Cyclone Energy (ACE). ACE is a named storm's potential for wind and storm surge destruction. Total ACE is a way meteorologists measure how busy a hurricane season is.
An ACE Index above 126 is considered above normal, while an ACE Index below 73 is considered below normal. For example, the 2021 season had an ACE Index of 142, which is above normal, while the even busier 2020 season had an ACE Index of 180. We haven’t had a below-normal season since 2015 when the ACE Index measured 63.
CSU uses two weather parameters to make forecasts for the potential total ACE Index in a given season. The first is the strength of the Atlantic multi-decadal oscillation (AMO). AMO is defined as the natural variability of sea surface temperatures and atmospheric pressure in the North Atlantic. CSU uses the AMO in combination with the forecast ENSO Index, which is our La Niña and El Niño. The NOAA Climate Prediction Center is currently forecasting our current La Niña to remind this winter, before transitioning closer to its neutral phase (No La Niña or El Niño). A La Niña would lead to less wind shear in the Atlantic Ocean, which could translate to more storms.
So, what does this all mean?
Colorado State University is predicting:
- 40% chance of an ACE Index of approximately 130, which would typically mean 13-16 named storms, 6-8 hurricanes, and 2-3 major hurricanes.
- 25% chance of an ACE Index of approximately 170, which would typically mean 15-18 named storms, 9-11 hurricanes, and 4-5 major hurricanes.
- 25% chance of an ACE Index of approximately 80, which would typically mean 9-12 named storms, 3-5 hurricanes, and 1-2 major hurricanes.
- 10% chance of an ACE Index of approximately 50, which would typically mean 6-9 named storms, 2-3 hurricanes, and 0-1 major hurricanes.
Remember an average hurricane season includes 14 named storms, 7 hurricanes, and 3 major hurricanes.
Colorado State University will release its full quantitative outlook on April 7. The National Hurricane Center typically releases its forecast in mid to late May, but the big date is to remember is June 1, the official start.