Showers and thunderstorms are expected across the southern and eastern US this week, with heavy rain and localized flooding, particularly near the Gulf Coast. Monsoonal moisture will bring rain and potential flooding to parts of the Southwest. Heat and fire weather threats will continue to impact the West. Read More >
...THE METEOROLOGY OF WINTER WEATHER IN WISCONSIN...
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...DURING THE FALL AND WINTER... WE BEGIN TO SEE COLD POLAR AIR PUSHING FARTHER SOUTH ACROSS THE COUNTRY DURING THE FALL SEASON. WEATHER SYSTEMS WHICH FORM ALONG THE BOUNDARY BETWEEN COLD AIR TO THE NORTH AND WARM AIR TO THE SOUTH OCCASIONALLY DEVELOP INTO MAJOR WINTER STORMS. WISCONSIN/S LOCATION PLACES IT RIGHT IN THE PATH OF SOME OF WINTER/S WORST STORMS.
-SUCH STORMS ARE USUALLY LARGE AND INTENSE LOW PRESSURE SYSTEMS COVERING TENS OF THOUSANDS OF SQUARE MILES.
...WHERE WINTER STORMS DEVELOP... MAJOR WINTER STORMS THAT AFFECT WISCONSIN USUALLY DEVELOP IN THE JET STREAM HUNDREDS OR THOUSANDS OF MILES AWAY FROM THE STATE...OFTEN OVER THE PACIFIC OCEAN. THEY THEN ENTER THE WESTERN UNITED STATES... CROSS THE ROCKY MOUNTAINS AND EVENTUALLY RE-DEVELOP OVER THE CENTRAL OR SOUTHERN GREAT PLAINS. THE STORMS THEN TAKE AIM ON THE MIDWEST.
THERE ARE SEVERAL TYPES OF WINTER STORM SYSTEMS
-LOWS FORMING OVER THE OKLAHOMA PANHANDLE AREA THAT PICK UP MOISTURE FROM THE Gulf of America AND MOVE NORTHEAST TOWARD INDIANA OR SOUTHERN WISCONSIN. THESE USUALLY PRODUCE THE HEAVIEST AMOUNTS OF SNOW.
-CLIPPER TYPE LOWS THAT MOVE SOUTHEAST OUT OF WESTERN CANADA... AND THEN CROSS NORTHERN ILLINOIS. THESE LOWS TYPICALLY PRODUCE DRIER FLUFFY SNOW.
-LOWS THAT MOVE NORTH FROM THE LOWER MISSISSIPPI VALLEY... RESULTING IN VERY WET SLUSHY snow. -WESTERN LOWS THAT MOVE FROM THE CENTRAL ROCKIES AND THE CENTRAL PLAINS.
...WINTER STORM PRECIPITATION... PRECIPITATION WITH MOST WINTER STORMS FALLS TO THE NORTH OF THE STORM/S CENTER. AS A RESULT...A STORM MOVING FROM THE PLAINS INTO NORTHERN ILLINOIS WILL KEEP WISCONSIN IN THE AREA OF GREATEST PRECIPITATION FOR THE LONGEST PERIOD OF TIME.
-AS THE STORM MOVES EAST OF THE BADGER STATE... POLAR AIR IS OFTEN DRAWN IN FROM CANADA. WIND AND COLD AIR FROM THE NORTH SOMETIMES COMBINE TO CAUSE WIND CHILL TEMPERATURES TO REACH 20 BELOW TO 50 BELOW ZERO.
-TYPICAL SNOW ACCUMULATIONS IN A WINTER STORM USUALLY RANGE FROM 6 TO 12 INCHES. DURING SOME WINTERS...A POWERFUL STORM MAY DEPOSIT AS MUCH AS 20 TO 30 INCHES OVER A 2-DAY PERIOD...WITH DRIFTS OF 7 TO 12 FEET OR MORE.
-THE PRECIPITATION CAN ALSO REDUCE VISIBILITIES THAT MAKE IT DIFFICULT FOR MOTORISTS TO SEE VEHICLES IN FRONT OF THEM.
...INFLUENCE OF LAKE MICHIGAN AND LAKE SUPERIOR... AS COLD AIR FLOWS OVER THE UNFROZEN WATERS OF LAKE SUPERIOR AND LAKE MICHIGAN IT PICKS UP ADDITIONAL MOISTURE. THE RESULTANT LAKE-EFFECT SNOW SHOWERS THAT CAN BE LOCALLY HEAVY...OFTEN FALLING AT THE RATE OF 2 TO 4 INCHES PER HOUR. THE FAR NORTHERN WISCONSIN COUNTIES AND THE EASTERN TIER OF COUNTIES ARE MOST LIKELY TO EXPERIENCE LAKE- EFFECT SNOWS.
-PARTS OF THE GOGEBIC RANGE IN IRON COUNTY FROM UPSON TO HURLEY HAVE AN AVERAGE WINTER SNOWFALL OF 135 TO 168 INCHES.
-AT THE OTHER END OF THE SPECTRUM...THE FAR SOUTHERN TIER OF COUNTIES AVERAGE AROUND 40 INCHES EACH WINTER SEASON.
...FREQUENCY AND TYPES OF WINTER STORM EVENTS... ON AVERAGE...SOUTHERN WISCONSIN EXPERIENCES ABOUT TWO OR THREE MAJOR WINTER EVENTS EACH WINTER...WHILE NORTHERN WISCONSIN AVERAGES ABOUT 6 STORM EVENTS.
-THE EVENT COULD BE HEAVY SNOW...BLIZZARDS...ICE STORMS...HEAVY SLEET...OR A COMBINATION OF EVERYTHING.
...BEST MONTHS FOR WINTER STORMS... MAJOR WINTER EVENTS USUALLY OCCUR FROM MID-NOVEMBER THROUGH MID- APRIL. HOWEVER...ACROSS THE NORTHERN HALF OF WISCONSIN A WINTER STORM IS POSSIBLE DURING THE MONTH OF OCTOBER...AND LATE APRIL INTO EARLY MAY. JANUARY IS THE MOST FAVORED MONTH FOR THEIR OCCURRENCE ACROSS THE STATE.
...WISCONSIN SNOWFALL RECORDS... A SUMMARY OF WISCONSIN STATE SNOWFALL AND TEMPERATURE RECORDS INCLUDE...
26.0 INCHES....GREATEST DAILY SNOWFALL... NEILLSVILLE/CLARK CO. DEC 27 1904 PELLA LAKE/WALWORTH CO. FEB 02 2011
31.0 INCHES....GREATEST SINGLE STORM...SUPERIOR/DOUGLAS CO. OCT 31 - NOV 3 1991
60.0 INCHES....DEEPEST SNOW ON GROUND...HURLEY/IRON CO. JAN 30 1997
103.5 INCHES...GREATEST MONTHLY TOTAL...HURLEY/IRON CO. JAN 1997
139.4 INCHES...GREATEST SEASONAL NORMAL SNOWFALL FOR THE 30-YEAR PERIOD OF 1971-2000...GURNEY/IRON CO.
174.4 INCHES...GREATEST SEASONAL NORMAL SNOWFALL FOR THE 22-YEAR PERIOD OF 1987-2009...HURLEY/IRON CO.
301.8 INCHES...GREATEST SEASONAL SNOWFALL TOTAL... HURLEY/IRON CO. 1996-97
-55F...........RECORD LOW TEMPERATURE FOR WISCONSIN NEAR COUDERAY /SAWYER CO./ SET ON FEBRUARY 2TH AND 4TH IN 1996.
FOR MORE INFORMATION ON WINTER WEATHER...VISIT... http://www.nws.noaa.gov/om/winter https://weather.gov/mke/?n-winter-wx-awareness https://readywisconsin.wi.gov https://emergencymanagement.wi.gov