2100 UTC Sunday 25 September to 2100 UTC Wednesday 28 September 2016
Issued by the Met Office, on behalf of the Maritime and Coastguard Agency, at 232059 UTC
Low pressure centred 986 northwest of Faeroes Sunday evening, with high pressure across eastern Europe and a weak ridge across the UK. During Monday, this low will clear north, with a ridge persisting across Cullercoats. Deepening low pressure systems will develop in the Atlantic, moving northeast. By midnight low pressure with centre 984 will be west of the UK, with high pressure persisting across Cullercoats. Through Tuesday this low will deepen, moving northeast to be 974 northwest of the UK by midday, however timings, exact track and depth of this feature remains low confidence. This continues northeast with a ridge of higher pressure following across Cullercoats on Wednesday, before a further low approaches from the west. Gales are likely during Tuesday across Cullercoats, perhaps severe north of 57N during the evening. A low risk of storm force across Fair Isle and Viking. These gradually east from the west during Wednesday, before further gales develop across Fair Isle later
High pressure will be centred 1024 across Biscay on Sunday evening, ridging northwards across Niton. A shallow low pressure could develop Monday morning across Shannon and Sole, with centre 1005, otherwise little change expected until Monday evening. Further deep Atlantic low pressure systems then develop, moving north east, to be centred 973 to the northwest of the UK by midday Tuesday, although confidence is low. High pressure will persist across much of Niton, centred 1030 near the Azores, and ridging north. This ridge will extend north by midnight Tuesday, as the low to the north gradually clears. However a further deep low will move into the Atlantic, to the northeast of Shannon by midday Wednesday. Some strong winds are possible west of 4W Monday. Gales are then likely to develop north of 50N during Tuesday, easing overnight, but returning in the west by Wednesday morning. These perhaps severe across northwest Shannon by Wednesday evening
Low pressure 986 will be centred South East Iceland Sunday evening, moving northeast, with a ridge of high pressure across the UK. The low clears north by midnight, with a transient ridge following. However a deep low pressure will move northeast to be centred 984 the west of Rockall by midnight Monday. This deepening and moving northeast to be centred 973 Bailey midday Tuesday, however confidence is low in the exact track, depth and timing of the system. This will continue northeast, clearing Fair Isle by midnight, with a ridge of high pressure following. However further low pressure is expected to move northeast, reaching west of Bailey by Wednesday evening with centre 974. Strong winds Sunday evening easing Monday morning. Gales spreading east Tuesday, turning severe at times south of low centre, with storms possible Bailey and Hebrides. These ease from the west Wednesday, before further severe gales, perhaps storms, spreads east into Rockall, Bailey and Shannon
Extended outlook overview
The extended outlooks are issued once a day, at 2300 GMT and cover the next 3 to 5 days.
For the extend outlooks the waters surrounding the British Isles are divided into three areas; Cullercoats, Portpatrick and Niton. These three areas reflect the coverage areas of the UK's Navtex transmitters, which overlap in some areas.
The extended outlook forecast contains details of the likelihood of gales or storms, a general synopsis and a general forecast for the area of coverage of each Navtex transmitter.
In the UK, the Maritime & Coastguard Agency (MCA) is responsible for the provision of Maritime Safety Information (MSI) to ships at sea, which includes the broadcast of warnings and forecasts. The Met Office initiates warnings and prepares routine forecasts for dissemination on behalf of the MCA.
Caution: The internet is not part of the Maritime Safety Information system and should never be relied upon as the only means to obtain the latest forecast and warning information. Access to the service may be interrupted or delayed from time to time, updates may also be delayed. Please refer to GMDSS services, INMARSAT SafetyNET or international NAVTEX for the latest information. When using these web pages, always check that the page on your screen is not from your cache. Use the Refresh or Reload button if in any doubt.