A Lake Effect Snow Watch is a bulletin issued by the National Weather Service in the United States to warn of heavy snowfall amounts that will be possible from convective snow generated by cold air masses passing over unfrozen lakes (lake effect snow). The criteria for amounts may vary over different county warning areas.
Example
MNZ020-037-181845- /O.NEW.KDLH.LE.A.0004.081219T0600Z-081220T0600Z/ SOUTHERN LAKE/LAKESHORE-CARLTON/SOUTHERN ST. LOUIS- 443 AM CST THU DEC 18 2008 ...LAKE EFFECT SNOW WATCH IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY EVENING... THE NATIONAL WEATHER SERVICE IN DULUTH HAS ISSUED A LAKE EFFECT SNOW WATCH...WHICH IS IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY EVENING.) LAKE EFFECT SNOW WILL DEVELOP AROUND MIDNIGHT TONIGHT...AND LAST THROUGH MUCH OF FRIDAY AND INTO FRIDAY EVENING. THE HEAVIEST OF THE SNOW WILL FALL ALONG THE HIGHER TERRAIN FROM DULUTH TO SILVER BAY...WHERE THE POTENTIAL EXISTS FOR UP TO 8 INCHES IN ISOLATED AREAS. THE HEAVIEST OF THE SNOW LOOKS TO FALL EARLY FRIDAY MORNING AROUND THE TIME OF THE MORNING COMMUTE. A LAKE EFFECT SNOW WATCH MEANS THE POTENTIAL EXISTS FOR HEAVY ACCUMULATION OF LAKE-EFFECT SNOW. TRAVEL AND COMMERCE MAY BE SIGNIFICANTLY AFFECTED. YOU ARE ENCOURAGED TO STAY CURRENT WITH THE LATEST WEATHER INFORMATION REGARDING THIS DEVELOPING WINTER STORM VIA LOCAL TELEVISION...RADIO...THE INTERNET...OR NOAA WEATHER RADIO. $$ LONKAReferences
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