Intense depression Tuva hits southern Norway and parts of Scotland.
11 August 2021
31 January 2008
By Jochen Kerkmann, Cecilie Wettre (EUMETSAT) and Jarno Schipper (ZAMG)
During the afternoon of 30 January 2008 rapid cyclogenesis over the North Atlantic led to the formation of storm Tuva within a few hours. The development was so explosive that even experts in the area of satellite image interpretation were surprised.
The satellite report (SatRep) from 18:00 UTC did not indicate the ongoing rapid cyclogenesis, which was finally analysed on the 00:00 UTC image of 31 January (see SatReps under See also). The reason why it was originally missed in the 18:00 UTC SatRep is probably the lack of some classical signs (cloud head and dry intrusion (dry slot)) typical of rapid cyclogenesis. However, the 18:00 UTC IR and WV images show other satellite features that indicate ongoing cyclogeneis:
- pronounced dark spot in WV image (indicative for a PV anomaly);
- developing cloud system east of the dark spot (not typically a cloud head), with conveyor belt structure;
- initiating wave structure of this cloud close to the dark spot;
- marked cold air cloudiness (e.g. open and closed cell convection) behind the new cloud system.
The following NWP key parameters (18:00 UTC, ECMWF analysis) confirm the cyclogenesis:
- the location of the PV anomaly ;
- the PVA maximum in the left exit region of the jet streak;
- the pronounced warm advection (WA )/ cold advection (CA) dipole;
- the isohypses at 1000 hPa being perpendicular to the isohypses at 500 hPa.
In summary, returning to the 18:00 UTC SatRep, at least a 'wave' should/could have been analysed. Due to the contrast of WA/CA, the PVA and the stratospheric air behind indicating the ongoing cyclogenesis, this wave rapidly went into the process of Rapid Cyclogeneis and developed into a 'nice' occlusion within a few hours.
The satellite image below shows this impressive spiral occlusion of storm Tuva (named by the Norwegian Weather Service) to the north of Scotland on 31 January 2008 at 08:00 UTC. As the storm approached Norway, on the west coast mean wind speeds of 26.6 m/s were measured, with gusts up to 33.7 m/s.
Later in the day strong winds were also encountered in the Skagerrak, northern Denmark and along the west coast of Sweden. Fortunately, no major damage was reported, but several roofs blew off houses, and around 50 leisure boats were damaged. The biggest problem was probably with air traffic in Oslo because the storm brought a lot of snow.
NOAA-18 AVHRR RGB NIR1.6, VIS0.8, VIS0.6 image (31 Jan 12:07 UTC, source: met.no)
Met-9 Animation IR10.8 Channel (29 Jan 15:45 UTC–31 Jan 15:45 UTC, AVIsource: met.no)
Met-9 WV6.2 image with height of PV equal 1.0 PVU (30 Jan 06:00 UTC, source: ZAMG)
Wind observations over Southern Norway (31 Jan 12:00 UTC, source: met.no)
SatRep analysis (30 Jan 12:00 UTC, source: ZAMG)
SatRep analysis (30 Jan 18:00 UTC, source: FMI)
SatRep analysis (31 Jan 00:00 UTC, source: KNMI)
Rapid cyclogenesis over the North Atlantic (24 January 2008)
Winter storm Kyrill leaves a trail of destruction across Southern England and Central Europe (18 January 2007)
Latest case studies
Melting Greenland ice sheet cools North Atlantic Ocean
Observing the cooling of the North Atlantic Ocean during the last decade, using weather satellites.
Smoke and burned areas from Greek fires
Smoke and burned area scars from the Greek wildfires in Aug 2021 seen in satellite imagery.
Large smoke plume from wildfires in Russia
In Summer 2021 Russia saw unprecedented widespread wildfires ravage large swathes of Siberia.
Widespread smoke from Turkish fires
In summer 2021 parts of the Mediterranean Sea were shrouded in smoke from wildfires along Turkey's coast.
Devastating floods in western Europe
Catastrophic floods hit Germany, Belgium and parts of West Europe mid July 2021.