Gale warning
The examples and perspective in this article may not represent a worldwide view of the subject. |
A gale warning is an advisory or warning issued by the local competent authority in maritime countries about the existence of winds of gale force or above or the imminent occurrence of gales at sea. The purpose of gale warnings is to allow mariners to take precautionary actions to ensure their safety at sea.
In the United States, warnings are issued by the National Weather Service to areas experiencing, or about to experience, winds within the range of 39 to 54 miles per hour or 63 to 69 km-h ( approximately 34 to 48 knots). A wind advisory is a weather related advisory issued by the National Weather Service if winds are forecast to be 31-39 mph for at least 1 hour; or any gusts to 46-57 mph.
In the UK gale warnings are issued by the Meteorological Office and are broadcast by radio four times a day at fixed times on 198 kHz in the shipping forecast, part of the broadcast output of BBC Radio 4. If there is to be a considerable time before the next Shipping Forecast, an extra gale warning is issued and read out between programmes. Warnings are issued for sea areas surrounding the UK for all predictions of winds of Beaufort Force 8 or above, the forecasts extending as far north as Iceland and as far south as southern Spain.
Met Éireann, the Irish meteorological office, issue warnings for sea areas around Ireland, with stretchs of coast defined by the headlands of Ireland (e.g. Fair Head, Malin Head, Mizen Head, Carnsore Point), and an area forecast for the Irish Sea.
Though usually associated with tropical cyclones, winds strong enough to catalyze a gale warning can occur in other conditions as well, including from anticyclones, or high-pressure systems, in the continental interior. However the warning is most commonly issued in coastal areas, and is primarily directed at marine rather than land-based interests — and the term high wind warning is often substituted for "gale warning" in non-maritime settings.
The insignia for a gale warning is two red triangular flags, one placed above the other (only one such flag denoting a small craft advisory).
A similar warning is issued by Environment Canada's Meteorological Service of Canada for lakes and oceans within Canada's juridiction.
Example of Wind Advisory
URGENT - WEATHER MESSAGE NATIONAL WEATHER SERVICE JUNEAU AK 451 AM AKDT SAT OCT 18 2008 DIXON ENTRANCE TO CAPE DECISION COASTAL AREA- INCLUDING THE CITIES OF...CRAIG...KLAWOCK 451 AM AKDT SAT OCT 18 2008 ...WIND ADVISORY IN EFFECT FROM 4 PM THIS AFTERNOON TO 3 PM AKDT SUNDAY... THE NATIONAL WEATHER SERVICE IN JUNEAU HAS ISSUED A WIND ADVISORY...WHICH IS IN EFFECT FROM 4 PM THIS AFTERNOON TO 3 PM AKDT SUNDAY. A STRONG FRONT WILL MOVE ACROSS THE SOUTHERN PANHANDLE THIS AFTERNOON BRINGING WIND GUSTS TO 45 MPH...ESPECIALLY IN EXPOSED LOCATIONS ALONG THE OUTER COAST AND NEAR HYDABURG. THESE WINDY CONDITIONS WILL CONTINUE THROUGH SUNDAY A WIND ADVISORY MEANS THAT SUSTAINED WIND SPEED OR FREQUENT GUSTS WILL OCCUR BETWEEN 40 AND 60 MPH. THIS STATEMENT WILL BE UPDATED BY 5 PM AKDT TODAY OR SOONER IF CONDITIONS WARRANT.