Gale warning

Gale warning flags (USA)

Weather services issue a gale warning for maritime locations currently or imminently experiencing winds of Gale Force on the Beaufort scale. Gale warnings (and gale watches) allow mariners to take precautionary actions to ensure their safety at sea or to seek safe anchorage and ride out the storm on land. Though usually associated with deep low-pressure areas, winds strong enough to catalyze a gale warning can occur in other conditions too, including from anticyclones, or high-pressure systems, in the continental interior.

U.S. Usage

Maritime

In the United States, the National Weather Service issues gale warnings for marine areas (oceans, sounds, estuaries, and the Great Lakes) experiencing, or about to experience, winds within the range of 34 knots (63 km/h; 39 mph) to 47 knots (87 km/h; 54 mph).[1] In United States maritime warning flag systems, two red pennants indicate a gale warning; the use of one such flag denotes a small craft advisory.

The National Weather Service issues a storm warning for higher winds of 48 knots (89 km/h; 55 mph) to 63 knots (117 km/h; 72 mph) at sea. In the event of a tropical cyclone, however, a tropical storm warning replaces both the gale warning and the storm warning. In this situation, the storm warning maritime flag is also used in lieu of the gale warning pennants, regardless of the intensity of the tropical storm.

Land

The National Weather Service issues a similar high wind warning (Specific Area Message Encoding code: HWW) for high winds on land. The criteria vary from place to place; however, in most cases, the warning applies to winds of 40 miles per hour (64 km/h) to 73 miles per hour (117 km/h) for at least 1 hour; or any gusts of 58 miles per hour (93 km/h) to 114 miles per hour (183 km/h) on land unless a tropical storm warning, blizzard warning, winter storm warning, severe thunderstorm warning, dust storm warning, or tornado warning covers the phenomenon.

U.K. usage

In the United Kingdom, the Meteorological Office issues gale warnings, and radio broadcasts them four times a day at fixed times on 198 kHz in the Shipping Forecast, part of the broadcast output of BBC Radio 4. If a considerable time will intervene before the next Shipping Forecast, forecasters may issue an extra gale warning, read between programmes. The Meteorological Office issues warnings for sea areas surrounding the United Kingdom for all predictions of winds of Beaufort scale Force 8 or greater, the forecasts extending as far north as Iceland and as far south as southern Spain.

Robert FitzRoy developed the first weather forecasting and storm warning system. On 1st September 1860 weather reports began to be collected at the Meteorological Office in London via electric telegraph and on the 5th February 1861 the first storm warning was issued[2]. After his death in 1865 the storm warning service was discontinued due to the ongoing debate about its scientific accuracy but the increased loss of life caused a public outcry and a campaign in press and in parliament saw the restoration of storm warnings in 1867. The service continues to this day and is now known as the iconic Shipping Forecast.

Met Éireann, the Republic of Ireland meteorological office, issues an area forecast for the Irish Sea and warnings for sea areas around Ireland with headlands of Ireland (e.g. Fair Head, Malin Head, Mizen Head, Carnsore Point) defining stretches of coast.

Meteorological Service of Canada issues a similar gale warning for lakes, oceans, and other marine areas within jurisdiction of Canada.

Example

The following is an example of a Gale Warning issued by the National Weather Service office in North Webster, Indiana.[3]

URGENT - MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE NORTHERN INDIANA
901 PM EDT WED OCT 29 2014

LMZ043-046-300915-
/O.CON.KIWX.GL.W.0014.141031T1200Z-141101T0900Z/
NEW BUFFALO MI TO ST JOSEPH MI-MICHIGAN CITY IN TO NEW BUFFALO MI-
901 PM EDT WED OCT 29 2014

...GALE WARNING REMAINS IN EFFECT FROM 8 AM FRIDAY TO 5 AM EDT
SATURDAY...

* WINDS...NORTHWEST 15 TO 25 KNOTS WITH GUSTS TO 30 KNOTS BY
  DAYBREAK FRIDAY...VEERING NORTH TO 35 KNOT GALES WITH GUSTS TO
  45 KNOT GALES FRIDAY. NORTH WINDS DIMINISHING TO 20 TO 30
  KNOTS WITH GUSTS TO 35 KNOT GALES LATE FRIDAY NIGHT.

* WAVES..5 TO 8 FEET LATE THURSDAY NIGHT...BUILDING TO 14 TO 20
  FEET FRIDAY...SUBSIDING TO 8 TO 12 FEET LATE FRIDAY NIGHT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A GALE WARNING MEANS WINDS OF 34 TO 47 KNOTS ARE IMMINENT OR
OCCURRING. OPERATING A VESSEL IN GALE CONDITIONS REQUIRES
EXPERIENCE AND PROPERLY EQUIPPED VESSELS. IT IS HIGHLY
RECOMMENDED THAT MARINERS WITHOUT THE PROPER EXPERIENCE SEEK SAFE
HARBOR PRIOR TO THE ONSET OF GALE CONDITIONS.

&&

$$

STAY TUNED TO NOAA WEATHER RADIO FOR FURTHER DETAILS OR
UPDATES...OR CHECK OUR WEB SITE AT WEATHER.GOV/IWX/?N=MARINE

See also

References

  1. ↑ National Weather Service. "Gale Warning". Glossary - National Weather Service. Retrieved 20 May 2011.
  2. ↑ "The Royal Charter Gale and the world's first National Forecasting Service". Met Office (UK) website.
  3. ↑ National Weather Service. "Gale Warning". Iowa Environmental Mesonet NWS Product Archive. Retrieved 20 May 2011.
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