A winter storm watch is issued by the National Weather Service of the United States when there is a possibility of heavy snow or potential of significant ice accumulations, without meeting a specific other winter criteria. The watch is typically issued 12 to 48 hours before the storm's expected arrival in the given area. The criteria for this watch can vary from place to place, which is true with other winter weather warning and advisories. As the event of the storm draws nearer in time and confidence in the occurrence of significant winter weather conditions and accumulation is increased, the weather watch will be upgraded to a winter storm warning or blizzard warning, depending on whether blizzard conditions will be met. If there is considerable confidence in significant ice accumulations with little to no snow, the watch will be upgraded to an ice storm warning. When confidence increases in the occurrence of winter like conditions that are not expected to reach warning or other winter criteria, a winter weather advisory will be issued instead. A watch could be discontinued altogether if neither warning nor advisory-level conditions are expected to be met and when the possibility of a winter storms fade. Generally, a watch is not issued when only advisory-level conditions are expected. Watches generally go into effect when the chance of meeting warning criteria ranges from 50% to 80% of snow.

Example of a winter storm watch

095 WWUS43 KMPX 030922 WSWLOT URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE Twin Cites/Chanhassen 322 AM CST Wed Feb 28 2021 ...SNOW AND BLOWING EXPECTED THURSDAY WITH SOME POTENTIAL FOR BLIZZARD CONDITIONS ALSO ACROSS SOUTH CENTRAL MINNESOTA Rain, snow, and possibly some freezing rainwill develop late tonight, mostly across southern and eastern Minnesota into western Wisconsin. A cold front will pass through Thursday morning with temperatures falling from the low to mid 30s to the teens in the afternoon. Precipitation will become widespread and turn to snow quickly early Thursday morning following the cold front. Snow will end from west to east in the afternoon and early evening. Total snow accumulations of 3 to 6 inches are expected across south central Minnesota into west central Wisconsin, with the highest totals of around 6 inches along and east of a line from Eau Claire to Ladysmith. In addition to the snow, strong northwest winds with gusts of 35 to 45 mph are expected Thursday through early Thursday evening. There is some potential for blizzard conditions across south central Minnesota where the strongest gusts are likely to occur. Much of this risk will depend on how much snow falls. A Winter Storm Watch is in effect Thursday through Thursday evening south and east of a line from St. James, to Mankato, Red Wing, Eau Claire, and Ladysmith. MNZ078-WIZ016-026>028-032100- /O.NEW.KMPX.WS.A.0003.210204T1200Z-210205T0300Z/ Goodhue-Rusk-Pepin-Chippewa-Eau Claire- Including the cities of Red Wing, Ladysmith, Durand, Chippewa Falls, and Eau Claire 322 AM CST Wed Feb 3 2021 ...WINTER STORM WATCH IN EFFECT FROM THURSDAY MORNING THROUGH THURSDAY EVENING... inches possible. Winds could gust as high as 40 mph. Counties. In Minnesota, Goodhue County. could significantly reduce visibility. The hazardous conditions could impact the morning or evening commute. PRECAUTIONARY/PREPAREDNESS ACTIONS... Monitor the latest forecasts for updates on this situation. && $$ MNZ077-082>085-091>093-032100- /O.NEW.KMPX.WS.A.0003.210204T1200Z-210205T0300Z/ Rice-Watonwan-Blue Earth-Waseca-Steele-Martin-Faribault-Freeborn- Including the cities of Faribault, St James, Mankato, Waseca, Owatonna, Fairmont, Blue Earth, and Albert Lea 322 AM CST Wed Feb 3 2021 ...WINTER STORM WATCH IN EFFECT FROM THURSDAY MORNING THROUGH THURSDAY EVENING... around 3 inches possible. Winds could gust as high as 45 mph. snow could significantly reduce visibility. The hazardous conditions could impact the morning or evening commute. PRECAUTIONARY/PREPAREDNESS ACTIONS... Prepare for possible blizzard conditions. Continue to monitor the latest forecasts for updates on this situation. && $$ Borghoff