2012 North Sea cyclone season
First storm formed July 18, 2012
Last storm dissipated Season currently active
Strongest storm Cindy – 115 mph (185 km/h), 949 hPa (28.03 inHg)
Tropical depressions 3
Tropical storms 3
Hurricanes 2
Major hurricanes 1
Total damages £30 million (2012 USD)
Total fatalities 0

The 2012 North Sea cyclone season was an average season with forming. The season began on July 1 and ended on October 1, 2012. The first storm of the season formed on July 18.

The North Sea cyclone basin is monitored by the British Windstorm Center (BWC) based in Dundee, United Kingdom, and the Met Office (MO) which is based in Exeter, UK.


Tropical Storm Alli

Tropical storm
Tropical storm (SSHWS)
Alli 2012 track.png
Duration July 18 – July 24
Peak intensity 60 mph (95 km/h) (1-min)  984 mbar (hPa)

An area of deep convection organised on July 18 and strengthened into a depression, according to the Met Office.[1] However, before the storm could strengthen, it made landfall in Wales with winds of 35 mph on July 20.[2] The system then significantly weakened over land,[3] but then restrengthened once it entered the North Sea. During the afternoon of July 21, the depression strengthened into Tropical Storm Alli, and moved into the BWC's area of responsibility (AoR).[4] On July 23, Alli made landfall near Berwick-upon-Tweed as a tropical depression.[5] Then in the early hours of July 24, the depression dissipated over the mountainous terrain of northern England.[6]

Hurricane Bonnie

Category 2 hurricane
Category 1 hurricane (SSHWS)
Bonnie 2012 track.png
Duration August 2 – August 6
Peak intensity 90 mph (150 km/h) (1-min)  969 mbar (hPa)

An area of intense thunderstorms was first noted off the coast of Berwick-upon-Tweed by the Met Office on July 31, where there was already a high chance (70% or more) of the system becoming a tropical cyclone within the next two days.[7] The next day, August 1, the area of investigation was upgraded to a 100% chance of forming into a depression as a circulation developed.[8] Then on August 2, the BWC had reported that a tropical depression had developed 45 miles east of Berwick-upon-Tweed.[9] Due to favorable conditions, the depression strengthened into Tropical Storm Bonnie six hours later while forecast to become a hurricane.[10] As it moved further away from land, it strengthened into the seasons first hurricane.[11] The storm continued to strengthen, peaking at 100 mph from the Met Office and 90 mph from the BWC. Before landfall, the hurricane weakened back into a tropical storm.[12] Bonnie then made landfall on Germany with sustained winds of 65 mph.[13]

Hurricane Cindy (Debby)

Category 3 hurricane
Category 3 hurricane (SSHWS)
Counterclockwise vortex Debby-Cindy 2012 track.png
Duration September 2 – September 5
Peak intensity 115 mph (185 km/h) (1-min)  949 mbar (hPa)

A hurricane formed in the Atlantic on August 28, and was named Debby by the National Hurricane Center. It strengthened into a Category 3 hurricane in the next few days. On September 2, the National Hurricane Center issued their final advisory and handed over responsibility to the Met Office. Wind speeds at the time were near 115 mph.[14] As it moved into the Met Office AoR, it was renamed