Rain clearing Orkney Wednesday morning and Shetland during the afternoon. Fresh or strong SW'ly winds.

Thursday starting mostly dry, with rain and strong to gale SE'ly winds spreading north later. Blustery showers and strong to gale WSW'ly winds following for Friday. A better weekend, with much lighter winds and a few scattered showers.

Next week perhaps cool and bright with a few showers and mainly light winds. The showers possibly more frequent and wintry later, as freshening E'ly winds back N'ly.

GENERAL SITUATION AND SYNOPSIS 06:00 UTC
A flat ridge extends north over Scotland from an anticyclone to the south of the UK, bringing a cloudy W'ly airflow. This will back SW'ly later today, as the high slips south across Europe. Tonight Atlantic low pressure will drive fronts across the Northern Isles in a strengthening SW'ly airflow.

Later on Thursday a vigorous depression - swinging northeast towards the British Isles - will bring its strong circulation and fronts over the area as it tracks north past Scotland.

The low, continuing north past Shetland, will leave a very strong and showery SW to W'ly airflow across the north of Scotland for Friday. This will quickly ease though, as the low continues east over the Baltic and pressure builds southeast from Iceland. As a result the next Atlantic depression is expected to follow an easterly track over southern Britain during the weekend.

This sets the scene for well into next week, with an anticyclone near Iceland maintaining a ridge towards Scotland and a moderate E'ly airflow over the Northern Isles. As the present prognosis has pressure falling over Scandinavia, there is a hint of a strengthening N'ly airflow as the last weekend of March approaches..

FORECAST FOR NEXT THREE DAYS
Confidence level: Weather type - high. Timing - high/medium.
Temperatures in the daily range 7° to 9° Celsius, down to around 5° Celsius overnight.

TUESDAY 16th: Mostly dry and, though generally cloudy, reasonably bright. There may be one or two light showers, these most likely across Shetland this morning. F4-5 W'ly winds backing SW'ly and increasing F5-6. Dry with some clear spells this evening and at first tonight. However, thickening cloud will bring some rain into Orkney later in the night, this reaching Shetland by dawn tomorrow.
Sea state - Moderate or slight, with a 1 to 2 metre NW'ly swell.

WEDNESDAY 17th: The day starting cloudy with outbreaks of rain, but Orkney turning drier and brighter during the morning and Shetland by early afternoon. F5-6 SSW'ly winds, occasionally F6-7 later. During the evening, thicker cloud may bring a little rain back into Shetland from the northwest.
Sea state - Moderate or slight, with a 1 to 2 metre NW'ly swell.

THURSDAY 18th: A reasonably bright and mostly dry start to the day. However, as F6 S to SE'ly winds increase F6-7 and locally gale F8, thickening cloud will bring rain north during the afternoon and evening. Around midnight in Orkney and during the early hours for Shetland, clearer conditions with blustery showers will spread from the southwest as strong to gale-force winds veer SW'ly.
Sea state - Moderate or slight, with a 1 to 2 metre SW'ly swell.

10-DAY OUTLOOK
Confidence level: Weather type - medium. Timing - low/medium.
Temperatures in the daily range around 8° Celsius down to about 5° Celsius.

FRIDAY 19th: A bright day with blustery showers, driven along by gale-force SW to WSW'ly winds.

SATURDAY 20th - SUNDAY 21st: Winds easing light and variable by Saturday morning. Then mostly dry and bright with winds becoming moderate SE'ly by late Sunday.

MONDAY 22nd - FRIDAY 26th: Mainly bright with a few showers and a cool E'ly wind increasing fresh at times. Possibly turning more wintry, with strengthening N'ly winds as the following weekend approaches.

Be aware that the weather over north-west Europe - and especially around the Northern Isles - is part of an ever-changing and dynamic system. Therefore regard the '10-Day Outlook' as a guide only - there are times when any outlook going beyond about 36 to 48 hours is likely to prove unreliable.

Always check the latest forecast from the UK Met Office before undertaking any weather-dependent activity.
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