A Lake Effect Snow Advisory is issued by the National Weather Service of the United States when lake effect snow may pose a hazard or is life-threatening. The snow must be completely caused by a convective snow development over a lake and not by a low pressure system. The criteria for this advisory vary from area to area.
Prior to the 2008-09 winter storm season, there was the Lake-Effect Snow and Blowing Snow Advisory, specific for when blowing snow another hazard expected in the advised area. The Lake-Effect Snow Advisory for Lake-Effect Snow and Blowing Snow has since replaced it.
Examples
URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE SALT LAKE CITY UT 1136 AM MST FRI DEC 31 2010 ...LAKE EFFECT SNOW TO IMPACT THE WASATCH FRONT THROUGH MIDNIGHT TONIGHT... .A WELL DEVELOPED LAKE EFFECT SNOW BAND IS EXPECTED TO REMAIN INTACT INTO THE OVERNIGHT HOURS TONIGHT. THE BAND IS CURRENTLY BRINGING MODERATE TO PERIODS OF HEAVY SNOW TO THE EASTERN TOOELE AND NORTHWESTERN SALT LAKE VALLEY AREAS THIS AFTERNOON. THIS BAND IS EXPECTED TO HOLD TOGETHER THROUGH OR JUST AFTER MIDNIGHT TONIGHT...GRADUALLY SHIFTING THROUGH THE SALT LAKE VALLEY LATER THIS AFTERNOON BEFORE DISSIPATING OVER DAVIS COUNTY. UTZ002-003-010300- /O.NEW.KSLC.LE.Y.0002.101231T1836Z-110101T0900Z/ NORTHERN WASATCH FRONT-SALT LAKE AND TOOELE VALLEYS- INCLUDING THE CITIES OF...BRIGHAM CITY...OGDEN...BOUNTIFUL... SALT LAKE CITY...TOOELE 1136 AM MST FRI DEC 31 2010 ...LAKE EFFECT SNOW ADVISORY IN EFFECT UNTIL 2 AM MST SATURDAY... THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A LAKE EFFECT SNOW ADVISORY...WHICH IS IN EFFECT UNTIL 2 AM MST SATURDAY. * AFFECTED AREA: THE WASATCH FRONT FROM THE TOOELE VALLEY NORTH TO THE INTERSTATE 84 CORRIDOR. * SNOW ACCUMULATIONS: GENERALLY 1 TO 4 INCHES OF ADDITIONAL NEW SNOWFALL IS EXPECTED. THE POSSIBILITY OF UP TO 6 INCHES EXISTS IN NORTHWESTERN SALT LAKE AND NORTHEASTERN TOOELE VALLEYS. * TIMING: THE LAKE BAND IS EXPECTED TO BE OVER NORTHEASTERN TOOELE AND NORTHWESTERN SALT LAKE COUNTY AREAS THROUGH THIS AFTERNOON. THE BAND IS EXPECTED TO SHIFT INTO THE SALT LAKE METRO AREA LATE THIS AFTERNOON AND EVENING BEFORE SHIFTING NORTH INTO DAVIS COUNTY. THE BAND IS EXPECTED TO DISSIPATE OVER DAVIS COUNTY AROUND THE MIDDLE OF THE NIGHT. * IMPACTS: DRIVING CONDITIONS ARE EXPECTED TO DETERIORATE RAPIDLY FOR AREAS AFFECTED BY THIS LAKE EFFECT BAND. SNOWPACKED AND ICY ROADS ARE LIKELY...AS WELL AS REDUCED VISIBILITIES BELOW 1/2 MILE DURING MODERATE TO AT TIMES BRIEF HEAVY SNOWFALL. PRECAUTIONARY/PREPAREDNESS ACTIONS... A LAKE EFFECT SNOW ADVISORY MEANS LAKE-EFFECT SNOW SHOWERS ARE EXPECTED OR OCCURRING AND TRAVEL WILL BE DIFFICULT IN SOME AREAS. LAKE-EFFECT SNOW SHOWERS TYPICALLY ALIGN THEMSELVES IN BANDS AND WILL LIKELY BE INTENSE ENOUGH TO PRODUCE SEVERAL INCHES IN LOCALIZED AREAS WITH SUDDEN RESTRICTIONS IN VISIBILITY. USE CAUTION WHEN TRAVELING. FOR WINTER ROAD CONDITIONS FROM THE UTAH DEPARTMENT OF TRANSPORTATION VISIT...HTTP://WWW.COMMUTERLINK.UTAH.GOV OR DIAL 511. && $$ FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)References
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