Snow Across the Great Lakes, Central Appalachians, and Northeast; Unsettled Weather in the West

Light to moderate snow will continue into Saturday over the Great Lakes, Central Appalachians, and Northeast. This weekend into next week, a series of atmospheric rivers will bring gusty winds, periods of heavy rain, and mountain snow to northern California and the Pacific Northwest. Colder temperatures are in store for the weekend from the Great Lakes to East Coast. Read More >

National Weather Service Watches and Warnings

The National Weather Service issues watches and warnings for hazardous weather, including severe thunderstorms and tornadoes. A watch covers a large area and means that meteorologists have determined that atmospheric conditions are favorable for a hazardous weather event. A warning covers a small area and means that meteorologists have determined that a hazardous weather event is imminent, or have received reports that the event is already occurring.
Watches are intended to heighten awareness. Once a watch is issued you should frequently monitor weather information for updates and possible warnings. Postpone outdoor activities until the threat has ended. If you cannot postpone such activities, you should at least have some way of receiving upto- date weather information and have a plan of action if

threatening weather approaches or a warning is issued for your area. National Weather Service meteorologists use a combination of reports from weather spotters and technology such as Doppler radar and satellite data to analyze storms and make warning decisions. Once the meteorologist determines that a

storm has a high probability of producing severe weather, a warning is issued. Warnings are no longer issued for entire counties, but are issued based upon the expected track of the storm, focusing only on locations that are expected to be directly impacted by severe weather. Advances in technology resulted in a dramatic improvement in the accuracy of warnings for severe thunderstorms and tornadoes over the past 20 years. Once a warning is issued by your local National Weather Service office, the warning is immediately disseminated by local broadcast news media. The warning is also broadcast

over NOAA All-Hazards Weather Radio. Remember, the period after a warning is issued is not the appropriate time to develop a safety plan. You should already have a plan in place and be prepared to immediately act upon it once a warning is issued.
Despite improvements in technology and our scientific knowledge of severe weather, the technology and the science have limitations. We are likely many years away from having the ability to issue successful warnings for all severe weather events. For this reason, it is important that you maintain a heightened sense of awareness when a watch is issued. Keep a close eye on the weather and be prepared to act quickly in case a warning never comes.
Remember that severe thunderstorms sometimes produce tornadoes with little or no warning. This is one of numerous

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