2005 Azores subtropical storm
Meteorological history | |
---|---|
Formed | 4 October 2005 |
Dissipated | 5 October 2005 |
Subtropical storm | |
1-minute sustained (SSHWS/NWS) | |
Highest winds | 50 mph (85 km/h) |
Lowest pressure | 997 mbar (hPa); 29.44 inHg |
Overall effects | |
Fatalities | None reported |
Areas affected | Azores |
IBTrACS | |
Part of the 2005 Atlantic hurricane season |
The 2005 Azores subtropical storm was the 19th
The subtropical nature of this unnamed system was determined several months after the fact, while the National Hurricane Center was performing its annual review of the season. Upon reclassification, the storm was entered into HURDAT, the official hurricane database.
Meteorological history
The system originated out of an upper-level low just west of the Canary Islands on 28 September. The low organized itself over the next days, producing several bursts of convection. While remaining non-tropical with a cold core it moved gradually west to northwest. On 3 October, it became a broad surface low about 400 nautical miles (740 kilometres; 460 miles) southwest of São Miguel Island in the Azores.[1] Early on 4 October, convection increased as the surface low organized itself, and the system became a subtropical depression.[2]
Around the same time, the depression turned northeast into a
At the time, the system was not believed to have been subtropical. However, there were several post-season findings that confirmed that the system was indeed one. The first finding was the cloud pattern, which had deep convection around the centre and was better organized with a well-defined centre of circulation. In addition, the system had a warm core more typical of tropical cyclones as opposed to the cold core of extratropical cyclones. The warm-core nature also meant that there were no warm or cold fronts attached to the system, as temperatures did not change ahead of and behind the system,[4] until an unrelated cold front passed the Azores.[5] Satellite imagery suggested that the system was briefly a tropical storm as the warm core was found; however, the widespread wind field and the presence of an upper-level trough confirmed that it was only subtropical.[2]
Impact, classification and records
Tropical storm-force winds were reported across parts of the Azores, primarily on the eastern islands. The strongest winds were reported on
The 2005 Azores storm was not classified as a subtropical storm until April 2006, after a reassessment by the National Hurricane Center.[7] Had it been operationally classified as such, it would have been named Tammy.[8] Every year, the National Hurricane Center (NHC) re-analyzes the systems of the past hurricane season and revises the storm history if there is new data that was operationally unavailable.[2] This reanalysis revealed that the storm became a subtropical storm on 4 October, making it the earliest forming 19th Atlantic tropical or subtropical storm on record.[9][10] The previous record holder was an unnamed 1933 tropical storm that developed on 26 October.[9] It held this distinction until 2020, when Hurricane Teddy attained tropical storm strength on 14 September.[11][12]
See also
- Timeline of the 2005 Atlantic hurricane season
- List of Azores hurricanes
- List of unnamed tropical cyclones
References
- ^ doi:10.1175/2007MWR2074.1. Archived from the original(PDF) on 10 September 2008. Retrieved 8 September 2008.
- ^ a b c d e "Tropical Cyclone Report: Unnamed Subtropical Storm" (PDF). National Hurricane Center; National Oceanic and Atmospheric Administration. 10 April 2006. Retrieved 31 October 2006.
- ^ "Tropical Cyclone Report: Hurricane Vince" (PDF). National Hurricane Center; National Oceanic and Atmospheric Administration. 22 February 2006. Archived (PDF) from the original on 24 May 2006. Retrieved 4 May 2006.
- ^ "History for Santa Maria, Azores: Week of October 2, 2005 through October 8, 2005". Weather Underground. 8 October 2005. Archived from the original on 5 October 2017. Retrieved 8 August 2008.
- ^ "History for Santa Maria, Azores: Thursday, October 6, 2005". Weather Underground. 6 October 2005. Archived from the original on 17 August 2016. Retrieved 8 August 2008.
- ^ "History for Santa Maria, Azores: Tuesday, October 4, 2005". Weather Underground. 4 October 2005. Archived from the original on 5 October 2017. Retrieved 7 August 2008.
- ^ "Tropical Weather Summary - 2005 Web Final". National Hurricane Center; Central Pacific Hurricane Center. Archived from the original on 16 October 2020. Retrieved 23 October 2020.
- ^ Masters, Jeff (14 April 2006). "Should-have-been-Tammy | Category 6". Weather Underground. Archived from the original on 26 October 2020. Retrieved 23 October 2020.
- ^ a b "Atlantic hurricane best track ("HURDAT")". National Oceanic and Atmospheric Administration; NHC Hurricane Research Division. 1 January 2008. Archived from the original on 16 September 2008. Retrieved 10 August 2008.
- ^ "Atlantic storm could become Epsilon; possible Zeta forming in southwest Caribbean". Avoyellestoday.com. Avoyelles Publishing Company. 19 October 2020. Archived from the original on 22 October 2020. Retrieved 23 October 2020.
- Miami, Florida: National Hurricane Center. Archivedfrom the original on 16 September 2020. Retrieved 14 September 2020.
- The Miami Herald. Chatham Asset Management. Archivedfrom the original on 14 September 2020. Retrieved 14 September 2020.
External links
- NHC's Tropical Cyclone Report on the storm