Storm warning
 | The examples and perspective in this articlemay not represent aworldwide viewof the subject.(September 2017) |
At sea, astorm warningis a warning issued by theNational Weather Serviceof theUnited Stateswhen winds between 48 knots (89 km/h, 55 mph) and 63 knots (117 km/h, 73 mph) are occurring or predicted to occur soon. The winds must not be associated with a tropical cyclone.[1]If the winds are associated with a tropical cyclone, atropical storm warningwill be substituted for the storm warning and less severegale warning.
In US maritime warning flag systems, a red square flag with a black square taking up the middle ninth of the flag is used to indicate a storm warning (the use of two such flags denotes ahurricane force wind warningor ahurricane warning). The same flag as a storm warning is used to indicate a tropical storm warning.
On land, the National Weather Service issues a 'high wind warning' (Specific Area Message Encoding code: HWW) for storm-force winds, which also encompasses the lessergale-forceand greaterhurricane forcewinds. In most cases, the warning applies to winds of 40-114 MPH for at least 1 hour; or any gusts of 58-114 miles per hour on land unless a tropical storm warning, blizzard warning, winter storm warning, severe thunderstorm warning, or dust storm warning covers the phenomenon. Winds in excess of 115 MPH (100 kt) will always result in new issuance of anextreme wind warningshortly before their onset, typically right before theeyewallof a majorhurricanemakes landfall, but possibly as a substitute for asevere thunderstorm warningin an extremederechoevent. The only exception is that if the extreme winds are associated with a tornado, atornado warning(or more likely atornado emergency) will be issued instead.
Weather Warning Flags (United States)
[edit]-
Small Craft Advisory Flag -
Gale Warning Flags -
Storm Warning Flag -
Hurricane Warning Flags
Example
[edit]The following is an example of a storm warning issued by the National Weather Service office inSeattle, Washington.[2]
246 WHUS76 KSEW 180451 MWWSEW URGENT - MARINE WEATHER MESSAGE NATIONAL WEATHER SERVICE SEATTLE WA 851 PM PST SUN JAN 17 2010 PZZ150-153-156-170-173-176-181300- /O.UPG.KSEW.GL.W.0087.000000T0000Z-100118T2300Z/ /O.NEW.KSEW.SR.W.0003.100118T0451Z-100118T2000Z/ COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND OUT 10 NM- COASTAL WATERS FROM JAMES ISLAND TO POINT GRENVILLE OUT 10 NM- COASTAL WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER OUT 10 NM- COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND 10 TO 60 NM- COASTAL WATERS FROM JAMES ISLAND TO POINT GRENVILLE 10 TO 60 NM- COASTAL WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER 10 TO 60 NM- 851 PM PST SUN JAN 17 2010 ...STORM WARNING IN EFFECT UNTIL NOON PST MONDAY... THE NATIONAL WEATHER SERVICE IN SEATTLE HAS ISSUED A STORM WARNING...WHICH IS IN EFFECT UNTIL NOON PST MONDAY. THE GALE WARNING IS NO LONGER IN EFFECT. PRECAUTIONARY/PREPAREDNESS ACTIONS... A STORM WARNING MEANS WINDS OF 48 TO 63 KNOTS ARE IMMINENT OR OCCURRING. RECREATIONAL BOATERS SHOULD REMAIN IN PORT OR TAKE SHELTER UNTIL THE WINDS AND WAVES SUBSIDE. COMMERCIAL VESSELS SHOULD PREPARE FOR VERY STRONG WINDS AND DANGEROUS SEA CONDITIONS...AND CONSIDER REMAINING IN PORT OR TAKING SHELTER IN PORT UNTIL WINDS AND WAVES SUBSIDE. && $$
See also
[edit]References
[edit]- ^National Weather Service."Storm Warning".Glossary - National Weather Service.Retrieved21 July2011.
- ^National Weather Service."Storm Warning".Iowa Environmental Mesonet NWS Product Archive.Retrieved21 July2011.