Irene (2005)

A strong tropical wave moved off the west coast of Africa on 1 August and developed into Tropical Depression Nine on 4 August about 600 nautical miles southwest of the Cape Verde Islands. The system wandered across the central Atlantic, fluctuating between depression and tropical storm strength as it encountered varying wind shear and dry air. Beginning about 11 August it steadily strengthened while moving northwest, became a hurricane on 15 August, and turned east-northeast. Irene weakened as it moved into the far North Atlantic and was absorbed by a larger extratropical low on 18 August.

Irene remained well offshore for its entire life and did not make any coastal landfalls. No coastal tropical cyclone watches or warnings were required, and there were no reports of damage or casualties tied to the storm.

The hurricane reached its maximum intensity on 16 August with peak sustained winds of 90 knots (about 103 mph) and a best-track minimum central pressure of 970 mb. That peak made Irene a Category 2 hurricane on the Saffir–Simpson scale while it was roughly 300 nautical miles northeast of Bermuda.

Storm surge and rainfall impacts were minimal because Irene stayed over the open Atlantic. The NHC report lists no reliable buoy or ship reports of tropical-storm-force winds, and no specific storm surge heights or heavy rainfall totals were recorded for cities, counties, or coastal areas.

There were no reported deaths—direct or indirect—and no reported damage associated with Irene. The regions most affected were open-ocean areas along the storm’s path, with satellite and reconnaissance aircraft observations providing most of the data used to document the cyclone.

Noteworthy items include Irene’s long life as a Cape Verde-type cyclone and its development to a moderate hurricane at relatively high latitude well north of Bermuda. Forecast track errors through 72 hours were smaller than the 1995–2004 average, while longer-range (96–120 h) track errors were larger than the earlier average; intensity forecasts were generally better than the 10-year mean.