Last week, low pressure was kept at a distance by blocking high pressure over Scandinavia. This week, however, high pressure will gradually move toward eastern Europe, creating space for low pressure to draw closer to the North Sea. As a result, conditions over the North Sea will gradually deteriorate.
Currently, low pressure still lingers over the northern Atlantic Ocean just south of Greenland. A broad band of high pressure extends southeast from the Greenland Sea through southern Scandinavia into central and eastern Europe. As a result, frontal troughs are unable to move past Iceland and the UK. On Wednesday, high pressure will move southeast into eastern Europe, eventually settling over Ukraine until the start of next week. Low pressure will reach Iceland on Thursday, with associated frontal troughs starting to cross the North Sea.
The predominantly southeasterly winds today will gradually turn south on Wednesday, while strengthening. After the first frontal trough crosses the North Sea on Thursday, winds will veer further and become southwesterly. By the end of today, many of the shipping forecast regions will already experience strong to near gale winds (6 to 7 Bft). The Fisher and German Bight regions will experience favourable conditions the longest, with strong winds arriving by Wednesday afternoon. By then, Fair Isle and Viking could already see winds increasing close to gale force (8 Bft). On Thursday, conditions will deteriorate further. The southwesterly wind will generally reach between 5 and 7 Bft over the southern half of the North Sea and between 7 and 9 Bft over the northern half of the North Sea. The highest winds are expected just west of southern Norway, peaking around 45 knots with gusts of around 55 knots.
By the end of today, the significant wave height will increase to between 1.0 to 3.5 metres from the German Bight to Fair Isle, respectively. Under the influence of the strengthening southerly winds and a long fetch, waves will increase to up to 5.0 metres in the north by the end of Wednesday. Until then, the southern North Sea will remain relatively calm with significant wave heights ranging from 0.5 to 2.0 metres. During frontal passage on Thursday, the significant wave height will generally reach between 1.0 and 3.0 metres over the southern half of the North Sea and between 3.0 and 6.0 metres over the northern half. Highest waves, just over 6.0 metres, are expected over northern Viking.
In the night to Friday, conditions will improve slightly, with winds dropping temporarily to fresh or strong (5 or 6 Bft) on Friday morning. The significant wave height will also temporarily decrease to between 1.0 and 3.0 metres. The next frontal trough will start crossing the North Sea later on Friday and Saturday. Winds will increase to strong to gale force (6 to 8 Bft) during the frontal passage before decreasing again to moderate to strong (4 to 6 Bft) on Saturday. Waves will reach between 4.0 and 5.0 metres north of Dogger on Friday. Improved working conditions are expected on Saturday as waves gradually decrease to below 2.0 metres south of 58°N, lasting until early Sunday.
On Sunday, a deep low pressure area will arrive between Scotland and Iceland. This could result in the worst conditions of this week. Winds are expected to reach gale force (8 Bft) over the entire North Sea, with some weather models even suggesting 9 Bft winds over the northern part. Significant wave heights will range between 2.0 to 4.0 metres over the southern North Sea and between 4.0 to 7.0 metres over the northern North Sea. Conditions will calm down again in the new week.
