Through Gilles MATRICON, meteorologist
Posted on 02/15/20, updated on 2/16/20 at 9:22 a.m.-
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This Sunday at 9 a.m., the weather conditions remain strongly windy, stormy near the coast of the English Channel even if the strongest gusts do not exceed 105 km / h. Inland, the wind is still blowing strongly in the interior of Finistère as well as in the Cambrai region (59) with a gust at 96 km / h measured.
At sea, conditions are very bad off the coast of Brittany, and generally in Nord-Gascogne with vagues more than 10 meters high measured off Pointe Saint-Mathieu in Finistère.
15.4 meters! It’s the height of a #wave relieved by a buoy located off Pointe Saint-Mathieu in Finistère in #Brittany this morning, the height of a 5-story building! pic.twitter.com/waPNUiD1gn
– The Weather Channel (@lachainemeteo) February 16, 2020
At 8 a.m., the situation changes little compared to the previous hour, with the maintenance of sometimes violent winds from Brittany to Normandy where gusts reach 116 km / h at the Pointe du Raz (29), 115 km / h at Saint- Ségal (29), 112 km / h at Gatteville (50) and the island of Batz (29), 111 km / h at Fécamp (76), 107 km / h at Rostrenen (29). These sometimes violent winds reach Cape Gris Nez (62) in Hauts-de-France with a gust at 105 km / h measured.
In the passage of the # tempêteDennis, the wind blows violently in #Brittany, the sea is cleared this morning. Waves from the sea, almost 8 meters high, in some places submerge the Pouldreuzic coastal road (29). Source: https://t.co/4hHz1FPfaF pic.twitter.com/dbPvaPZYFT
– The Weather Channel (@lachainemeteo) February 16, 2020
Inland, gusts frequently reach 80 km / h from Rennes (35) to Lille (59) via Rouen (76), Alençon (61) and even 90 km / h to Evreux (27). In the Paris region, a gust reached 80 km / h at Roissy (95).
After a heavily watered night, the rains weakened temporarily on the south of Brittany but the Odet, Isole and Laïta reacted strongly with some overflows observed this morning.
At 7 a.m., the wind continues to strengthen from Brittany to Normandy with a gust at 133 km / h measured at the Pointe du Raz (29) this Sunday at 7 am. Inland, the wind is also strengthening with 108 km / h at Rostrenen (29), 102 km / h at Damblainville (14) and 100 km / h at Livry (14).
The speed of movement of the cloud band over the north of France which corresponds to the disturbance of the # tempêteDennis sweeping the British Isles testifies to the power of the #JetStream which reaches nearly 400 km / h! pic.twitter.com/x6K2TktQvU
– The Weather Channel (@lachainemeteo) February 16, 2020
At 6 o’clock, the strongest winds are reported on the neighboring regions of the English Channel with gusts at 128 km / h at Barfleur (50) and at the Pointe du Raz (29) and 123 km / h at the island of Batz (29). Inland, gusts reach 90 km / h in Lille (59), Caen (14) and Cambrai (59), 80 km / h in Evreux (27), Alençon (61); Rennes (35) and Roissy (95) and 75 km / h in Paris (75).
These winds are maintained throughout the morning in these regions, and tend to reach the Loire by strengthening slightly.
Under the disturbance of Storm Dennis, continuous moderate to heavy rain occur in southern Brittany with 50 mm recorded at Plouay (56), 47 mm at Pluvignier (56) and 44 mm at Tourch (29), corresponding to 2 weeks of precipitation.
A vast low pressure system winds in the south of Iceland, which undergoes a very violent blizzard (snowstorm) with red alertness. The wind reached 256 km / h at Hafnarfjall on the west of the island yesterday. At sea, waves nearly 20 meters high have been detected.
Waves more than 10 meters high observed this morning in the #Cornwall. https://t.co/pqId4YjoQv
– The Weather Channel (@lachainemeteo) February 15, 2020
Within this low pressure group, the Dennis depression is already formed and is located in the south of Greenland. The pressure at its center, at 920 hPa, is still falling.
“The eye” of the # tempêteDENNIS in formation off Iceland reminds of a cyclone. Its pressure at its center is currently 920 hPa … a value that we find in the heart of #cyclones adults in tropical latitudes! Source: https://t.co/Eu2Yjr1qs5 pic.twitter.com/yaOEYECISL
– The Weather Channel (@lachainemeteo) February 15, 2020
On the British Isles, the strongest gusts have already reached since last night 159 km / h at Aonach Mor in Scotland, 149 km / h at Great Dun Fell in England, 141 km / h at Capel Curig in Wales and 115 km / h at Belmullet in Ireland. Due to the storm, Easyjet canceled more than 200 flights this Saturday, from and to England. Storm Dennis made his first victims with 2 teenagers drowned on the Kent coast.
Waves more than 10 meters high observed this morning in the #Cornwall. https://t.co/pqId4YjoQv
– The Weather Channel (@lachainemeteo) February 15, 2020
This Saturday at 7 p.m. in France, the wind strengthens near the Channel coasts with gusts reaching 113 km / h at Barfleur (50) and the island of Batz (29), 112 km / h at Ouessant (29), 109 km / h at Brignogan (29), 107 km / h at Cherbourg (50) and 100 km / h at Cap Gris Nez (62). In the interior, gusts reach 75 km / h in Rennes (35) and Caen (14) and 60 km / h in Alençon (61) and Lille (59).
The wind is strengthening in Brittany at Pouldreuzic (29). The state of the sea deteriorates with the approach of the # tempêteDennis, waves in some places submerge the coast road. Source: https://t.co/4hHz1FPfaF pic.twitter.com/gyQsdDbWOp
– The Weather Channel (@lachainemeteo) February 15, 2020
