Tropical Storm Grace (2009)

Tropical Storm Grace originated from a large extratropical cyclone that formed along a cold front on 27 September, roughly 470 mi (755 km) east of Cape Race, Newfoundland. However, the following day, convection began to decrease over the system, and the National Hurricane Center (NHC) ceased monitoring it. Over the following two days, the system executed a counter-clockwise loop near the Azores. During the afternoon of 4 October, convection redeveloped around the center of the low and was classified as a tropical storm near São Miguel Island. with winds estimated at 65 mph (100 km/h) early on 5 October; operationally it was held at 70 mph (110 km/h), but was downgraded due to uncertainties in the storm's intensity as it was progressing over cold waters. A large extratropical cyclone near Grace caused the storm to deteriorate in organization, with convection weakening and becoming asymmetric. By this time, the storm was over waters, likely inhibiting convective development. Shower and thunderstorm activity continued to diminish throughout the day on 5 October; however, Grace maintained tropical characteristics, namely a deep, warm core. Early on 6 October, the NHC issued their final advisory on Grace as it merged with a frontal system over the northeastern Atlantic. Just prior to merging, the lowest pressure in relation to the storm was recorded at 986 mbar (hPa; 29.12 inHg). The extratropical remnants of Grace persisted for roughly 18 hours before dissipating over the Celtic Sea early on 7 October. Although officially designated a tropical cyclone by the NHC, Météo-France, the French meteorological service, stated in their annual report to the World Meteorological Organization that Grace should not have been classified a tropical system. In their report, they argued that although the storm presented deep convection, an eye-like feature, and winds above 60 mph (95 km/h), the overall development of Grace was more similar to that of a mid-latitude non-tropical cyclone. They also criticized the NHC for warning on this system based on recent trends of the link between global warming and increased hurricane activity. ==Impact and records==

, Belgium|alt=Dark and stormy clouds with sunlight breaking through in the background Upon being classified a tropical cyclone within the Azores, a few islands received minor rainfall and high winds. Gusts up to were recorded on Ponta Delgada. While merging with the frontal system on 6 October, the storm's outer bands produced heavy rains and strong winds over parts of Portugal, resulting in some street flooding. In higher elevations, wind gusts were estimated to have exceeded . Due to the storm's relatively rapid forward movement by the time it reached the United Kingdom, rainfall was limited. In Ireland, of precipitation fell in the city of Cork. Sustained winds in the city were recorded up to . Rainfall in the country peaked at in Wexford. Near the coastline of Wales, a buoy recorded sustained winds up to , equivalent to a minimal tropical storm. Late on 6 October, the remnants of Grace moved inland over Wales, bringing heavy rains and high winds to the region. Maximum rainfall in the United Kingdom reached in Capel Curig. One ship, the Cap Castillo (call sign A8PI5), recorded sustained winds of on 5 October, while located about south of the storm's center. Operationally, Grace was not classified as a tropical storm until it reached latitude 41.2°N. In its Tropical Cyclone Report on Grace, the National Hurricane Center reported that the formation of Grace was poorly forecast. The first mention of the precursor low on 1 October predicted that it would not develop into a tropical or subtropical cyclone. Over the following three days, the system was not mentioned in the NHC's tropical weather outlooks until just prior to Grace's classification. The lack of preceding outlooks was attributed to the storm's unusual location and the sparsity of data for storms in the region. ==See also==