2006 Nova Scotia tropical storm

Infobox Hurricane
Name=Unnamed Tropical Storm
Type=Tropical storm
Year=2006
Basin=Atl
Image location=Unnamed Tropical Storm 17 july 1706Z.jpg


Formed=July 17, 2006
Dissipated=July 18, 2006
1-min winds=45
Pressure=998
Da

Inflated=
Fatalities=None reported
Areas=Newfoundland
Hurricane season=2006 Atlantic hurricane seasonThe 2006 Nova Scotia tropical storm was a short-lived tropical cyclone that was unnamed operationally during the season but was recognized during post-season analysis and given the designation AL022006. The second tropical storm of the 2006 Atlantic hurricane season, the system developed as an extratropical cyclone to the southeast of Nantucket, Massachusetts on July 16 from a dissipating cold front. It tracked northeastward over warm water temperatures, and on July 17 transitioned into a tropical storm after an area of convection developed over the center. The storm quickly reached peak winds of 50 mph (85 km/h) before encountering cooler waters and weakening. On July 18, it degenerated into a non-convective remnant low, and after crossing Newfoundland it dissipated on July 19. Impact in Canada was minimal, and no deaths were reported.

Meteorological history

A cold front moved off the East Coast of the United States late on July 13 and subsequently stalled over the western Atlantic Ocean.cite web|author=Eric S. Blake and John L. Beven|year=2006|title=Unnamed Tropical Storm Tropical Cyclone Report|publisher=National Hurricane Center|accessdate=2007-06-20|url=http://www.nhc.noaa.gov/pdf/TCR-AL502006_Unnamed.pdf] The front decayed and dissipated, leaving behind two areas of low pressure. The southern area was centered about 200 miles (320 km) south of Cape Hatteras, North Carolinacite web|author=MAINELLI/BEVEN|year=2006|title=July 16, 2006 Tropical Weather Outlook (2)|publisher=National Hurricane Center|accessdate=2007-06-20|url=ftp://ftp.met.fsu.edu/pub/weather/tropical/Outlook-A/2006071621.ABNT20] and ultimately became Tropical Storm Beryl,cite web|author=Richard Pasch|year=2006|title=Tropical Storm Beryl Tropical Cyclone Report|publisher=National Hurricane Center|accessdate=2007-06-20|url=http://www.nhc.noaa.gov/pdf/TCR-AL022006_Beryl.pdf] while the northern area was centered about 290 miles (470 km) south-southeast of Cape Cod, Massachusetts. The northern area developed into an extratropical low on July 16 after an upper-level trough approached it from the west. Moving northeastward over warm water temperatures of 80–82° F (27–28° C), the trough weakened, and late on July 16 the system separated itself from the dissipating cold front. Shortly thereafter, a large burst of convection developed near the center, and it is estimated the system transitioned into a tropical depression early on July 17 while located about 240 miles (390 km) southeast of Nantucket, Massachusetts.

Accelerating northeastward, the depression encountered favorable conditions for development, and intensified into a tropical storm six hours after becoming a tropical cyclone. A large curved band of convection formed in the northern portion of the storm, with other banding features becoming more prominent. It continued to strengthen, and late on July 17 the storm attained peak winds of 50 mph (85 km/h) while located about 245 miles (395 km) south of Halifax, Nova Scotia. Shortly thereafter, the storm encountered much cooler water temperatures after leaving the Gulf Stream. The storm quickly weakened as the convection rapidly diminished, and on July 18 it degenerated into a non-convective remnant low. The remnants crossed Newfoundland before turning to the east-northeast, and on July 19 the system dissipated.

Operationally, the storm was classified as a non-tropical gale. However, a post-season analysis of the storm provided enough evidence of tropical characteristics to warrant classifying it as an unnamed tropical storm. Observations analyzed the storm as having a symmetric warm-core, whereas in real time it was considered subtropical. Additionally, the storm was first assessed as a frontal low in real-time, though subsequent analysis indicated no frontal features and no cold air entrainment around the time of its peak intensity.

Impact, naming, and records

Upon entering the area of responsibility of the Canadian Hurricane Centre, a Canadian buoy recorded maximum sustained winds of 36 mph (56 km/h) with gusts to 44 mph (70 km/h).cite web|author=Canadian Hurricane Centre|year=2007|title=2006 Atlantic Hurricane Season Review|accessdate=2007-06-20|url=http://www.atl.ec.gc.ca/weather/hurricane/storm06.html] The same buoy recorded a pressure of 1001.2 mbar (29.57 inHg). The storm greatly weakened prior to moving across Newfoundland, and as a result impact was minimal. No official forecasts were issued for the system; however the Atlantic Storm Prediction Centre issued marine gale warnings for the storm.

As part of its routine post-season review, the National Hurricane Center occasionally identifies a previously undesignated tropical or subtropical cyclone based on new data or meteorological interpretation. The reanalysis of 2006 resulted in its re-classification as an unnamed tropical storm on December 15, 2006; had it been classified operationally, it would have been named Tropical Storm Beryl. The last fully-tropical cyclone to be first classified in post-analysis was Hurricane Eight in 1991, more often known as the Perfect Storm. Several subtropical cyclones were first classified during post-analysis since then, most recently in 2005.

Upon transitioning into a tropical cyclone at 39.1° N, the storm broke the record for the northernmost cyclogenesis in the Atlantic in July since reliable records started in 1940, surpassing that of Tropical Storm Arthur in 2002. It was also the northernmost tropical or subtropical cyclogenesis for an Atlantic tropical cyclone since a subtropical storm in December of 1975. Additionally, the cyclone became a tropical storm further north than any other Atlantic tropical cyclone in the month of July, and was further north than any other Atlantic storm since Tropical Storm Alberto in 1988.cite web| author=NHC Hurricane Research Division|title=Atlantic hurricane best track|publisher=NOAA|year=2007|accessdate=2007-06-20|url=http://www.aoml.noaa.gov/hrd/hurdat/easyhurdat_5106.html]

See also

*List of storms in the 2006 Atlantic hurricane season

References

External links

* [http://www.nhc.noaa.gov/pdf/TCR-AL502006_Unnamed.pdf NHC Tropical Cyclone Report]