Karen (2007)

A tropical wave that moved off West Africa developed into a tropical depression at 0000 UTC on 25 September 2007 about 720 nautical miles west-southwest of the Cape Verde Islands. It became Tropical Storm Karen about six hours later and moved generally west-northwest. Karen strengthened rapidly on 26 September, reached hurricane strength around 1200 UTC that day, then encountered strong upper-level wind shear and weakened back to a tropical storm by 0000 UTC 27 September. The circulation continued to weaken and became a tropical depression early on 29 September; the system dissipated after 1200 UTC 29 September, with remnant showers lingering near and east of the Leeward Islands for a few days.

Karen did not make any landfalls. Its track remained well out in the tropical Atlantic and it dissipated before reaching the Leeward Islands.

The peak intensity was estimated at 65 knots (75 mph) with a minimum central pressure near 988 mb, corresponding to a Category 1 hurricane at its peak around 1200–1800 UTC on 26 September 2007. Aircraft data (700 mb flight-level winds of 69 kt and SFMR surface winds of 62 kt) and satellite imagery supported the 65‑kt peak in post-storm analysis.

Because Karen stayed over the open Atlantic, there were no reported storm surge measurements tied to the cyclone and no reports of significant rainfall totals on land attributed to it. A nearby NOAA buoy (41041, at 14.5°N, 46.0°W) recorded a maximum 1‑minute wind of 43 kt at 0700 UTC 27 September when Karen’s center was about 75 nautical miles to the south; no ship reports of tropical-storm-force winds were received.

There were no reports of casualties or damage associated with Karen. The system posed little threat to land during its lifetime.

Karen’s formation was well anticipated in forecasts: the disturbance that became Karen was mentioned in the Tropical Weather Outlook nearly 57 hours before genesis. Official track and intensity forecasts showed somewhat larger than average track errors at short ranges but were generally successful in anticipating that increasing wind shear would limit or reverse Karen’s strengthening.