Shipping Forecast

AND HERE IS THE SHIPPING FORECAST ISSUED BY THE MET. OFFICE.....

Words that many have heard and from which most know the names DOGGER and GERMAN BITE but without knowing much more. The Shipping Forecast is broadcast four times each day on BBC Radio 4. Each bulletin contains 350 words and begins with warnings of gales (when issued) followed by a general summary of current weather conditions

Weather forecasts are extremely important for both sailors and airmen with the latest information of crucial importance for both comfort and safety. Operators can route ships and aircraft to avoid severe weather, reducing the risk of injury and damage.

Information is broadcast at regular intervals and provides details of current conditions and expected weather for the next few hours.

Gale warnings are also broadcast on the same frequency at the first available programe junction. If this happens not to coincide with a news bulletin, then the warning will be repeated after the next news bulletin.

Format of the Shipping Forecast
The Shipping Forecast is always given in the following order:-

Sea Areas Around the UK1. GALE WARNINGS: A listing of all sea areas where gale warnings are in operation. These are also broadcast on BBC Radio 4 at the first programe break following their receipt and at the end of the hourly news bulletin. Coast Radio Stations also broadcast gale warnings for adjacent sea areas soon after receiving them. See Sample Forecast


2. GENERAL SYNOPSIS: An account of the development and the movement of depressions and anticyclones (also when time permits, of fronts affecting the sea areas around the British Isles and North West Europe. See Sample Forecast


3. FORECASTS BY SEA AREAS: Some Sea Areas are grouped together, but always following the same order, which is clockwise around the British Isles, beginning with Viking to the North East and ending with South East Iceland.
The forecast by areas gives:-
a) Expected wind directions, Beaufort forces and changes.
b) The weather.
c) Visibility for the 24 hour period following the broadcast.

See Sample Forecast


4. ACTUAL WEATHER OBSERVATIONS: This information is obtained from various "Coastal Stations" situated around the British Isles and comprises:- Wind, Weather, Visibility, Barometer Pressure & Tendency, recently observed at the stations. See Sample Forecast

Terminology used in the Shipping Forecast
ANTICYCLONE: Area of high pressure, around which the wind moves in a clockwise direction, with the wind speed usually decreasing towards the centre, where winds are light and variable.

DEPRESSION: Area of low pressure, around which the wind moves in an anti-clockwise direction, with the wind speed increasing towards the centre, often resulting in gales.

SPEED & MOVEMENT OF HIGH & LOW PRESSURE FEATURES: The speed and movement of highs and lows given in the general synopsis, are described either by the "from" and "to" positions (Sea Areas), or by the use of the following terms:-

Slowly Moving at less than 15 knots
Steadily Moving at 15 to 25 knots
Rather Quickly Moving at 25 to 35 knots
Rapidly Moving at 35 to 45 knots
Very Rapidly Moving at over 45 knots

Depressions generally move eastward (though the track may sometimes be in any direction). The movement of a developing "Low" will usually be parallel to the isobars in it's warm sector, that normally towards the East Northeast. When occlusion is well developed, the Low will turn poleward and decelerate, eventually becoming slow moving as it decays over a further one or two days.

Anticyclones movements are even more variable. Commonly very sluggish, some Highs may remain almost stationary for days or maybe weeks. Large Highs, typically elliptical in shape, can appear to move a considerable distance. This is due to a local build up in pressure on one of the ridges and a fall in pressure over the original centre. This causes the "centre of gravity" to shift and completely alters the wind directions in the central area of the high.
Some small Highs are escorted by very "active" Lows to the front and rear. These Highs will travel at the same speed as the escorting Lows and are commonly very windy.

Wind always moves from a High to a Low pressure area.

BACKING: A Backing wind moves anti-clockwise.

VEERING: A Veering wind moves clockwise.

CYCLONIC: This means that wind changes will be consistent with the anti-clockwise rotation around a depression.

WEATHER: Described as Fair, Rain, Showers, Drizzle, Snow or Extensive Fog as appropriate.

SHOWERS: This covers the whole range from light showers to thunderstorms which are localised and typically last for half an hour or so.

RAIN: Means continuous and widespread precipitation, associated with fronts and depressions.

SQUALLY SHOWERS: (When strong winds are otherwise not forecast) This means that gusts of wind or squalls associated with the showers, will far exceed the forecast wind speed.
(Typically reaching 30 knots - Force 6 to 7 and sometimes more)

VISIBILITY: The terms explained...

GOOD Means more than 5 Nautical Miles
MODERATE Means 2 to 5 Nautical Miles
POOR Means 1,000 metres to 2 Nautical Miles
FOG Means less than 1,000 metres

TIME PERIODS: The terms explained...

IMMINENT Means within 6 hours of the time issued
SOON Means within 6 to 12 hours of the time issued
LATER Means more than 12 hours from the time issued

PRESSURE TENDENCY: The terms explained...

Falling or Rising - Slowly = 0.1 to 1.5mb change
Falling or Rising - 1.6 to 3.5mb change
Falling or Rising - Quickly = 3.6 to 6.0mb change
Falling or Rising - V.Rapidly = more than a 6.0mb change

The last two are significant with falling pressure as they probably indicate that strong winds or gales will follow.

LOCATING THE DEPRESSION: In the Northern Hemisphere, facing into the wind, the centre of the depression is on your right.

The Met Office Shipping Forecast Visit the Met. Office or BBC websites for the latest shipping forecast or tune in to BBC Radio 4.

Sample Forecast

THE SHIPPING FORECAST ISSUED BY THE MET OFFICE AT 1725 ON TUESDAY 17 JULY 2001

THERE ARE WARNINGS OF GALES IN PLYMOUTH BISCAY FINISTERRE SOLE LUNDY FASTNET IRISH SEA SHANNON

THE GENERAL SYNOPSIS AT 1300 LOW FASTNET 989 EXPECTED WIGHT 992 BY 1300 TOMORROW

THE AREA FORECASTS FOR THE NEXT 24 HOURS

VIKING NORTH UTSIRE SOUTH UTSIRE NORTH 4 OR 5, OCCASIONALLY 6 IN NORTH VIKING. SHOWERS. GOOD

FORTIES CROMARTY FORTH EAST OR NORTHEAST 4 OR 5, OCCASIONALLY 6 LATER. MAINLY FAIR. GOOD

TYNE DOGGER NORTHEAST 5 TO 7. RAIN LATER. GOOD BECOMING MODERATE

FISHER NORTH VEERING NORTHEAST 4 OR 5. MAINLY FAIR. GOOD

GERMAN BIGHT NORTHEAST 4 OR 5, OCCASIONALLY 6, VEERING SOUTH 4 OR 5 LATER IN SOUTH. RAIN LATER. GOOD BECOMING MODERATE

HUMBER THAMES EAST, VEERING SOUTH FOR A TIME, 5 TO 7, DECREASING 4 LATER. OCCASIONAL RAIN. MODERATE OR GOOD

DOVER WIGHT SOUTHEAST 5 TO 7 VEERING SOUTHWEST 4 OR 5, BECOMING CYCLONIC LATER. RAIN OR SHOWERS. MODERATE OR GOOD

PORTLAND SOUTHWEST 5 TO 7 BECOMING CYCLONIC 4 OR 5. RAIN OR SHOWERS. MODERATE OR GOOD

PLYMOUTH SOUTHWEST 5 TO 7, OCCASIONALLY GALE 8 OR SEVERE GALE 9 IN SOUTH, VEERING NORTHWEST 4 OR 5 LATER. RAIN OR SHOWERS. MODERATE OR GOOD

BISCAY SOUTHWEST 6 TO GALE 8, OCCASIONALLY SEVERE GALE 9 IN NORTH. SQUALLY SHOWERS. MAINLY GOOD

SOUTH FINISTERRE NORTHWEST 5 OR 6. SHOWERS. GOOD

NORTH FINISTERRE SOLE WEST VEERING NORTHWEST 6 TO GALE 8, OCCASIONALLY SEVERE GALE 9 AT FIRST. RAIN OR SQUALLY SHOWERS. MAINLY GOOD

LUNDY FASTNET CYCLONIC 5 TO 7 BECOMING NORTH OR NORTHEAST 6 TO GALE 8. RAIN OR SHOWERS. MODERATE OR GOOD

IRISH SEA NORTHEAST BACKING NORTH 6 TO GALE 8. OCCASIONAL RAIN. MODERATE OR GOOD

SHANNON NORTH OR NORTHWEST 5 TO 7, OCCASIONALLY GALE 8 IN SOUTH AT FIRST. RAIN DYING OUT. MODERATE OR GOOD

ROCKALL MALIN NORTHEAST 5 OR 6, OCCASIONALLY 7 IN SOUTH AT FIRST. SHOWERS. GOOD

HEBRIDES BAILEY FAIR ISLE FAEROES SOUTHEAST ICELAND NORTHEAST 4 OR 5, OCCASIONALLY 6 EXCEPT IN SOUTHEAST ICELAND. SHOWERS. GOOD