AHeavy Freezing Spray Warning is issued by theNational Weather Service of theUnited States to warn vessels that rapid accumulation andicing of freezing water droplets due to a combination of cold water, wind, cold air, and vessel or vehicle movement is likely. Accumulation rates of 2 cm per hour or greater must be possible for a warning to be issued, or else afreezing spray advisory would be issued.[1]
The following is an example of a Heavy Freezing Spray Warning issued by the National Weather Service office inMarquette, Michigan.[2]
URGENT - MARINE WEATHER MESSAGENATIONAL WEATHER SERVICE MARQUETTE MI1024 AM EST MON JAN 5 2015LSZ162-052330-/O.CON.KMQT.UP.W.0002.000000T0000Z-150110T0600Z/LAKE SUPERIOR WEST OF A LINE FROM SAXON HARBOR WI TO GRANDPORTAGE MN BEYOND 5NM-1024 AM EST MON JAN 5 2015 /924 AM CST MON JAN 5 2015/...HEAVY FREEZING SPRAY WARNING REMAINS IN EFFECT UNTIL 1 AM EST/MIDNIGHT CST/ SATURDAY...A HEAVY FREEZING SPRAY WARNING REMAINS IN EFFECT UNTIL 1 AM EST/MIDNIGHT CST/ SATURDAY.* TIMING: EXPECT HEAVY FREEZING SPRAY TO OCCUR UNTIL 1 AM EST /MIDNIGHT CST/ SATURDAY.PLEASE SEE THE LATEST MARINE FORECASTS FOR MORE DETAILEDINFORMATION.PRECAUTIONARY/PREPAREDNESS ACTIONS...A HEAVY FREEZING SPRAY WARNING MEANS HEAVY FREEZING SPRAY ISEXPECTED TO RAPIDLY ACCUMULATE ON VESSELS. THESE CONDITIONS CANBE EXTREMELY HAZARDOUS TO NAVIGATION. IT IS RECOMMENDED THATMARINERS NOT TRAINED TO OPERATE IN THESE CONDITIONS OR VESSELSNOT PROPERLY EQUIPPED TO DO SO...REMAIN IN PORT OR AVOID THEWARNING AREA.