Hurricane forecast for England, in October? That's right! Tropical Storm Grace just blow right by the United States and ended up near the United Kingdom a few days ago. Unusual, I'd say so! The storm developed off the coast of Azores, in late September as an extra-tropical area of low pressure. By October 4, the storm had formed and at 11:00 AST that day it was named Grace, by the National Hurricane Center (NHC) due to it's relatively deep convection and eye-like feature. Convection continued to persist due to low wind shear, even though the storm was already in waters not normally warm enough for a tropical storm to develop. Due to the intense jet stream, the tropical storm blew on a northeastern track over the Atlantic, rather than the more common southly track over the northwestern Atlantic. The storm intensified slightly as it moved over the waters and then began to decrease as it moved closer to the land surface, the next day. It's max winds where reported to peak at about 70 mph, for about one-minute. On October 6, Tropical Storm Grace dissipated over England, after bringing minor rainfall and high winds to Wales, Ireland and Capel Curig, United Kingdom.
According to the Hurricane Specialist's Unit (2009), "Operationally, Grace was not classified a tropical storm until it reached latitude 41.2°N; this marked the second northernmost formation of a tropical storm in the Atlantic on record, only Tropical Storm Alberto of 1988 had formed farther north." It also "...marked the farthest northeast a tropical cyclone formed in the Atlantic basin, surpassing that of Hurricane Vince in 2005."
Unfortunately these reports were proven to be incorrect after a post-storm analysis by the NHC, finding that "Grace had become a tropical storm 12 hours earlier than initially stated, becoming tropical at latitude 38.3°N." - source here.
Regardless if Tropical Storm Grace, was extra-tropical or just tropical, I'm sure it surprised a lot of weather forecasters!
Definition of Extratropical- "
-->Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of cyclones defined as synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth (outside the tropics) having neither tropical nor polar characteristics, and are connected with fronts and horizontal gradients in temperature and dew point otherwise known as "baroclinic zones." source
According to the Hurricane Specialist's Unit (2009), "Operationally, Grace was not classified a tropical storm until it reached latitude 41.2°N; this marked the second northernmost formation of a tropical storm in the Atlantic on record, only Tropical Storm Alberto of 1988 had formed farther north." It also "...marked the farthest northeast a tropical cyclone formed in the Atlantic basin, surpassing that of Hurricane Vince in 2005."
Unfortunately these reports were proven to be incorrect after a post-storm analysis by the NHC, finding that "Grace had become a tropical storm 12 hours earlier than initially stated, becoming tropical at latitude 38.3°N." - source here.
Regardless if Tropical Storm Grace, was extra-tropical or just tropical, I'm sure it surprised a lot of weather forecasters!
Track of Hurricane Grace (courtesy of weather underground)
Definition of Extratropical- "
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