Welcome to the Weekly Weather Update – your guide to the world’s oceans and seas. Each week, we highlight key marine weather patterns and analyze unusual or significant weather events. From calm spells under high pressure to tropical cyclones forming in equatorial waters, and from jet streams steering oceanic storms to anomalies in sea-surface temperature that shape global climate patterns. Here’s what this week’s weather has in store.
Low pressure gains its influence
Last week, high pressure dominated the North Sea, leading to generally calm weather across the region, with occasional unsettled conditions in the northern parts. This week, low pressure will gradually move in, bringing more unsettled weather overall, especially during the second half of the week.
High pressure remains over northwestern Russia, gradually shifting southeast later in the week. A ridge extending from this system covers the North Sea on Tuesday before moving east on Wednesday. Meanwhile, low pressure near Iceland persists, and an associated frontal trough will cross the North Sea later on Wednesday. This will bring unsettled weather to the central and northern North Sea, where winds are expected to increase to 20–25 knots, reaching 35–40 knots in the far northeast. Wave heights in these areas are forecast to reach 2–3.5 meters, and up to 4–5.5 meters in the northeastern parts.
Unsettled weather is expected over the North Sea on Thursday, especially later in the day. A secondary low will develop just north of Scotland during the night into Friday, leading to strengthening winds and rising seas over the central North Sea. Winds are forecast to increase to 20–25 knots, with stronger gusts further north. Significant wave heights will build to 2.5–4 meters, with higher values in northern areas.
Later on Friday, a very deep low (ex hurricane Humberto, see below) is expected just northwest of Ireland, bringing increasingly unsettled weather to the North Sea through Friday evening and into the weekend. From late Friday, winds and waves will rise rapidly across the entire region. Stormy conditions are most likely during the passage of a frontal trough associated with this low in the nigh to Saturday (Figure 1). Over the northern and a part of central North Sea, maximum wind speeds may reach 35–45 knots, while the rest of the region is expected to see widespread winds above 20–30 knots. Significant wave heights may build up to 3.5–5.5 meters over the Northern and central North Sea, while elsewhere they are expected to remain at 1.5–3 meters. The waves may even increase up to 8 meters in the far north regions and the southern Norwegian Sea and even increase this value on Saturday.
On Sunday and Monday, conditions are expected to improve slightly, though the weather will remain rather unsettled. Thus, calm and pleasant weather will gives way to unsettled, and at times stormy, conditions over the weekend. Please consult your latest weather forecast to stay up to date.
The power of two
Moving further into the Atlantic Ocean, something very interesting is unfolding. Two powerful atmospheric systems are currently active: Tropical Storm Imelda and Category 2 Hurricane Humberto. Although they are relatively close to each other, we will examine them separately to better understand their individual characteristics.
Category 2 Hurricane Humberto is currently gradually weakening. Initially, it is moving north-northwest, but later on Tuesday it will turn northeast. Wind speeds currently range from 80–90 knots, though the system is slowly losing strength. By the end of Tuesday, Humberto is expected to weaken to a Category 1 hurricane as it continues moving northeast, with winds decreasing to 75–80 knots by Wednesday. The weakening trend continues, and by late Wednesday, Humberto is forecast to become a post-tropical storm with winds of up to 70 knots. This post-tropical system will continue northeast and is expected to approach Ireland by Saturday, as mentioned earlier in this article.
Tropical Storm Imelda is expected to strengthen throughout Tuesday, reaching Category 1 hurricane status by the end of the day, with winds increasing to around 65–70 knots. As it continues moving northeast, Imelda intensifies further, with winds reaching up to 85–90 knots by Thursday morning. Afterward, the hurricane begins to weaken, transitioning into a post-tropical storm by Friday, with winds still ranging between 55–75 knots. On Friday, the system moves more northward toward Newfoundland and then turns northeast on Saturday. It is expected to gradually dissipate over the weekend.
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Figure 2. Track and development of Humberto and Imelda. Source: Imweather.com
There is a lot happening in the Atlantic Ocean, so staying updated is crucial!
Quiet on the Eastern Front
Compared to the Atlantic Ocean, the Pacific is relatively quiet at the moment. On Tuesday, Invest 93W is located west of the Philippines. This system is expected to move slowly northwest and may strengthen by the end of the week. It could potentially develop into a tropical storm while over the South China Sea, though this is still uncertain. It is recommended to keep an occasional eye on the weather updates.
Conclusion
Weather over the North Sea is expected to worsen significantly compared to last week. Calm conditions will give way to stormy, and in some areas, potentially dangerous—weather by the end of the week. Meanwhile, the Atlantic Ocean remains active, as it is currently in its peak hurricane season. The Eastern Pacific is relatively quiet this week, but significant activity could still occur over the next two months.
Stay updated on LinkedIn
We plan to post this Weekly Weather Update on our Infoplaza for Marine Weather Operations LinkedIn page as well. This is also the place where we will share other insightful marine weather articles, so be sure to follow us to never miss an update.
