Executive Summary: The 2018 Climate Impact Company North Atlantic seasonal tropical cyclone outlook is issued. The next update will be available around June 1. The outlook projects 12 tropical storms, 7 hurricanes and 3 intense hurricanes in 2018. The accumulated cyclone energy index forecast is 93. The outlook is slightly less active than the 30-year climatology and very similar to neutral ENSO climatology forecast for this season. The activity is considerably lower than last year. A transition from weak La Nina toward weak El Nino coupled with only near normal warmth of the ocean surface in the deep North Atlantic tropics are lead contributors to the forecast.
Projected Source Region, Tracks and Activity for 2018 in the North Atlantic
Regional forecast discussions: Based on the analog forecast and adjusted for the quasi-biennial oscillation a projection of expected activity for the 2017 season is indicated.
- Gulf of Mexico: Expect several tropical storms however the forecast does not indicate hurricanes in the Gulf of Mexico in 2018 with the exception of the Bay of Campeche and possibly Florida. The analogs favor the eastern half of the Gulf of Mexico for tropical cyclone activity.
- Mexico: Two events are forecast and at least one is an intense hurricane. The intense hurricane is projected as a low latitude system and these are usually most dangerous. Traveling across the central Caribbean Sea this system is likely early in the season before –QBO develops suppressing deep tropics activity. The forecast indicates a Lower Yucatan Peninsula strike and then westward across the Bay of Campeche. At least one other tropical system will follow this path.
- East Coast Virginia and north: Projected this summer season is an upper trough over the East-Central U.S. Therefore the upper wind across the East Coast is generally either a shearing westerly flow or favorable southerly current. Expect several tropical storms to affect the U.S. East Coast this season. One system gains hurricane intensity off the Mid-Atlantic Coast but drifts northeast away from the coast. The analog forecast favors an out-to-sea hurricane drifting into Nova Scotia.
- East Coast south of Virginia: Several tropical storms are likely to affect Florida on either side of the peninsula. The only hurricane risk is late in the season drifting north from the southwestern Caribbean Sea.
- Caribbean: The developing –QBO pattern implies that mid-to-late season may be relatively quiet in the Caribbean Sea. Prior to –QBO becoming established risk of an intense hurricane across Caribbean Sea is indicated. Typical of late season another intense hurricane is forecast to develop in the southwest Caribbean Sea and turn north toward Miami. There may be 1 or 2 other tropical cyclones occurring during the season.
