The combination of melting snow and some rainfall helped to push some western Wisconsin rivers out of their banks during the latter part of the month.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS ARX wrote it up.
The combination of melting snow and some rainfall helped to push some western Wisconsin rivers out of their banks during the latter part of the month.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS La Crosse, WI wrote its last area forecast discussion before the first event at Mar 20, 7:34 PM CST, 2 hours 26 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 834 PM CDT SUN MAR 20 2011 .UPDATE... VISIBILITIES RAPIDLY DROPPED ACROSS SOUTHEAST MINNESOTA SHORTLY AFTER 5 PM WITH LIGHT WINDS AND RECENT RAINS. MANY SITES DROPPED TO A QUARTER MILE OR LESS. THESE HAVE SINCE IMPROVED AS A TROUGH PASSAGE THERE HAS SHIFTED WINDS WESTERLY. FARTHER EAST... HOWEVER...VISIBILITIES HAVE BEEN ON THE WAY DOWN. KLSE BRIEFLY DROPPED TO A HALF MILE AND UP ON THE RIDGE HERE AT THE OFFICE WE ARE CURRENTLY NEAR ZERO. WITH THE TROUGH PASSAGE TAKING A LITTLE LONGER TO MOVE TOWARDS THE MISSISSIPPI RIVER AND POINTS EAST...HAVE PUT UP A DENSE FOG ADVISORY FOR COUNTIES ALONG AND NORTH OF I-90. THE END TIME OF 09Z MIGHT BE A BIT LONG...ESPECIALLY SAY FOR THE WINONA AND LA CROSSE AREA...BUT UP IN TAYLOR AND CLARK COUNTIES IT IS CONCEIVABLE VISIBILITIES DO NOT IMPROVE THERE UNTIL 06-09Z. OTHERWISE...PRECIPITATION HAS SHIFTED EAST OF THE AREA. CLOUDS MAY TAKE A LITTLE LONGER TO CLEAR THAN ORIGINALLY EXPECTED BASED ON TRENDS ON 11-3.9UM SATELLITE IMAGERY. LOW CLOUDS SEEM TO BE GETTING TRAPPED UNDERNEATH A STRENGTHENING SUBSIDENCE INVERSION...SEEN NICELY ON THE 00Z MPX SOUNDING. THINKING IS THAT THE CLEARING OF LOW CLOUDS IN SOUTHWEST MINNESOTA WILL MAKE ITS WAY EASTWARD DUE TO WEST WINDS BEHIND THE SURFACE TROUGH. HOWEVER...A SHIELD OF CIRRUS OVER THE CENTRAL PLAINS IS QUICKLY MAKING ITS WAY EAST-NORTHEAST IN THE WAKE OF TODAY\S SHORTWAVE TROUGH. THE COMBINATION OF THE CIRRUS AND SLOWER PROGRESSION OF LOW CLOUD CLEARING RESULTED IN DELAYING CLEARING IN THE UPDATED FORECAST. && .SHORT TERM...TONIGHT THROUGH WEDNESDAY AN ACTIVE WEATHER PATTERN WILL CONTINUE THIS WEEK WITH A MIX OF PRECIPITATION EXPECTED MONDAY NIGHT THROUGH THURSDAY...WITH SOME SIGNIFICANT SNOW ACCUMULATIONS POSSIBLE ACROSS NORTH CENTRAL WISCONSIN. IN THE NEAR TERM FOR THIS AFTERNOON AND EARLY EVENING HOURS...THE FOCUS IS ON A MID LEVEL TROUGH OVER THE DAKOTAS AND A SURFACE LOW OVER SOUTHWESTERN IOWA WITH A WARM FRONT EXTENDING EAST FROM IT TOWARD NORTHERN ILLINOIS. CONVECTION IS EXPECTED TO REDEVELOP NEAR THIS LOW PRESSURE SYSTEM ALONG THE WARM AND COLD FRONTS. THE LAST FEW RUNS OF THE RUC SUGGEST THAT PRECIPITATION MAY HAVE A HARD TIME REDEVELOPING ACROSS NORTHERN IOWA/SOUTHERN MINNESOTA/WESTERN WISCONSIN WHERE CLOUD COVER IS MORE PREVALENT IN THE COLD SECTOR. IT INSTEAD DEVELOPS STORMS DOWN IN THE WARM SECTOR ACROSS SOUTHERN IOWA AS THE LOW COMES ACROSS WHERE THE RUC SPC MESOANALYSIS SHOWS BETWEEN 1000-2000 J/KG OF MUCAPE. WILL MORE LIKELY SEE JUST DRIZZLE WITH THE MAIN LOW LEVEL MOISTURE TRANSPORT SHIFTED OFF TO THE EAST...BUT HAVE KEPT SOME CHANCES IN THERE THIS EVENING IN CASE ANYTHING CAN GET GOING ALONG THE FRONT. DRIER AIR WILL MOVE IN ACROSS THE UPPER MISSISSIPPI RIVER VALLEY LATER THIS EVENING WITH SKIES POSSIBLY CLEARING OUT OVERNIGHT. A RIDGE OF HIGH PRESSURE WILL NOSE DOWN INTO THE REGION FROM THE DAKOTAS ON MONDAY AND BRING A BRIEF BREAK TO THE ACTIVE WEATHER PATTERN. NOT MUCH IN THE WAY OF LOW LEVEL COLD AIR ADVECTION TAKING PLACE BEHIND THIS SYSTEM...SO TEMPERATURES SHOULD REMAIN SEASONAL OR SLIGHTLY ABOVE NORMAL MONDAY. CONDITIONS WILL QUICKLY CHANGE MONDAY NIGHT AS THE BROAD MID LEVEL TROUGH OF LOW PRESSURE SLOWLY PROPAGATES EASTWARD ACROSS THE ROCKIES AND INTO THE PLAINS. THE SURFACE COLD FRONT THAT COMES THROUGH TONIGHT ENDS UP STALLING OUT FROM EAST TO WEST ACROSS CENTRAL ILLINOIS TO SOUTHERN IOWA AND MEETS UP WITH A DEVELOPING LOW OVER CENTRAL NEBRASKA. THIS SURFACE SETUP WILL NOT CHANGE MUCH FROM MONDAY NIGHT INTO WEDNESDAY EXCEPT THAT THE LOW WILL SLOWLY TRACK EAST ALONG THE FRONT AND EVENTUALLY PASS INTO THE GREAT LAKES EARLY ON WEDNESDAY. ACROSS NORTHEAST IOWA AND FAR SOUTHERN WISCONSIN...PRECIPITATION TYPE WILL LIKELY BE RAIN THROUGHOUT THIS TIME SPAN WHERE TEMPERATURES WILL REMAIN THE WARMEST...THOUGH NOT IN THE WARM SECTOR. 0-3KM MUCAPE LOOKS MINIMAL AT BEST ACROSS THIS REGION...SO HAVE LEFT ANY MENTION OF THUNDER OUT ACROSS THIS AREA FOR THE TIME BEING. SHEAR PROFILES WILL BE MORE THAN IDEAL ACROSS NE IA/SW WI WITH STRONG VEERING WITH HEIGHT FROM THE SURFACE ON UP TO 6KM WITH A 50KT SPEED MAX AROUND 5KM. IF ANY INSTABILITY IS ABLE TO ADVECT INTO THIS REGION...SOME ELEVATED ORGANIZED CONVECTION WILL BE POSSIBLE WITH HAIL BEING THE MAIN THREAT. THE AREA FURTHER NORTH ACROSS SOUTHEAST MINNESOTA INTO CENTRAL WISCONSIN APPEARS TO BE MORE OF A TRANSITION ZONE WITH RAIN BEING THE MAIN PRECIPITATION TYPE. AS THE SURFACE LOW AND 850MB LOW PASS THROUGH EARLY ON WEDNESDAY...THE LOW LEVEL COLD LAYER SHOULD DROP DOWN INTO THE -6 TO -10C RANGE WITH THE ELEVATED WARM LAYER DROPPING TO AROUND 1C. THIS SHOULD LEAD TO AN IDEAL SLEET PROFILE BEFORE TURNING OVER TO ALL SNOW BY WEDNESDAY AFTERNOON. BY THIS TIME THE HEAVIEST PRECIPITATION SHOULD BE OVER...SO ANY SNOW ACCUMULATIONS WOULD LIKELY BE ON THE LIGHTER SIDE. GOING EVEN FURTHER NORTH ACROSS NORTH CENTRAL WISCONSIN...MAINLY ALONG THE I-94 CORRIDOR AND NORTH...THE PRECIPITATION THAT FALLS THROUGHOUT THIS EVENT WILL MORE SO BE IN A FROZEN FORM. SOME RAIN COULD MIX IN ON TUESDAY...BUT FROM TUESDAY NIGHT ONWARD THE THERMAL PROFILE LOOKS MORE CONDUCIVE FOR SNOW AND/OR SLEET. WITH THE MAIN MID LEVEL CLOSED LOW PROPAGATING THROUGH ON WEDNESDAY...SOME HEAVY SNOWFALL APPEARS POSSIBLE AS THIS COMES THROUGH WITH THE MAIN DEFORMATION BAND EXTENDING FROM NORTHERN MINNESOTA DOWN THROUGH NORTHERN WISCONSIN. SNOW ACCUMULATIONS WILL DEPEND ON HOW MUCH SLEET MIXES IN...BUT A DECENT ACCUMULATION LOOKS PROBABLE AT THIS POINT. WITH THE START TIME OF THE FROZEN PRECIPITATION NOT STARTING UNTIL BEYOND 48 HOURS...WILL BE HOLDING OFF ON ISSUING A WINTER STORM WATCH UNTIL LATER MODEL RUNS PRESENT A CONSENSUS ON THERMAL PROFILES AND FOR WHERE THE HEAVIEST SNOW BAND WILL SET UP. TO GO ALONG WITH ALL OF THE PRECIPITATION TYPE ISSUES...BROAD LOW LEVEL MOISTURE TRANSPORT WILL PUMP COPIOUS AMOUNTS OF MOISTURE UP INTO THE REGION FROM THE GULF. WITH ABOUT A HALF INCH TO AN INCH OF RAIN FALLING ON SUNDAY...MUCH OF THE RIVER SYSTEMS ACROSS THE AREA WILL BE FAIRLY SATURATED TO BEGIN WITH. ADDITIONAL RAINFALL AMOUNTS OF AN INCH TO TWO INCHES WILL LIKELY LEAD TO ADDITIONAL RIVER FLOODING. ALSO...THE PRESSURE GRADIENT WILL BE TIGHTENING UP ON THE NORTH SIDE OF THIS SYSTEM WITH WINDS BE PICKING UP AS WELL. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK ON INTO NEXT WEEKEND AS A SECONDARY SURGE OF COLD LOW LEVEL AIR DROPS DOWN INTO THE UPPER MISSISSIPPI RIVER VALLEY WITH A TROUGH OF LOW PRESSURE RETROGRADING INTO THE GREAT LAKES REGION FROM QUEBEC. THERE IS SOME DISAGREEMENT BETWEEN THE 20.12Z GFS AND ECMWF IN REGARDS TO TIMING AND STRENGTH OF A COUPLE WEATHER SYSTEMS GOING INTO THE WEEKEND WITH THE GFS SHOWING A MUCH STRONGER SURFACE LOW WITH THE ECMWF SHOWING A MUCH QUICKER SYSTEM WITH HIGH PRESSURE BUILDING IN QUICKLY BEHIND IT. WILL HAVE TO MONITOR IT THIS WEEK...BUT FOR NOW IT WARRANTS SOME SMALL CHANCES OF LIGHT SNOW. && .AVIATION...TONIGHT INTO MON NIGHT EARLY THIS EVENING...VLIFR CONDITIONS WERE BEING EXPERIENCED AT KRST AND IFR-LIFR CONDITIONS AT KLSE. THESE SHOULD GRADUALLY IMPROVE THROUGH THE EVENING AS A TROUGH PASSES AND SWITCHES WINDS TO THE WEST. CLEARING NOTED OVER SOUTHWEST MINNESOTA AS OF 01Z SHOULD MAKE ITS WAY INTO KRST BY 06Z AND KLSE BY 07Z. VFR CONDITIONS ARE THEN EXPECTED TO PERSIST THROUGH MONDAY AS A RIDGE OF HIGH PRESSURE MOVES ACROSS. MVFR/IFR CONDITIONS WILL RETURN FOR LATER MON NIGHT AS THE NEXT SFC LOW/MID LEVEL TROUGH...SURGE OF LOW LEVEL MOISTURE/LIFT SPREAD INTO THE REGION. AN EXTENDED PERIOD OF MVFR/IFR CONDITIONS THEN LOOKING LIKELY FROM TUE INTO WED. && .HYDROLOGY... AREA STREAMS AND RIVERS HAVE QUICKLY RISEN TODAY IN RESPONSE TO ABOUT A HALF INCH TO JUST OVER AN INCH OF RAIN THAT FELL OVERNIGHT. ADDITIONAL RAINFALL THIS EVENING IS EXPECTED TO BE MINIMAL WITH THE MAIN THUNDERSTORM ACTIVITY RELEGATED TO SOUTHERN IOWA AND SOUTHEAST WISCONSIN. AFTER A DRY DAY ON MONDAY...PRECIPITATION WILL START UP AGAIN MONDAY NIGHT AND WILL LIKELY LAST INTO THURSDAY AND FALL IN VARIOUS PRECIPITATION TYPES. THE BEST CHANCES FOR THE PRECIPITATION TO REMAIN LIQUID WILL BE ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN WITH MORE OF A MIX POSSIBLE ACROSS SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. ONE TO TWO INCHES OF QPF IS POSSIBLE MONDAY NIGHT THROUGH WEDNESDAY WHICH WILL ADD TO THE RIVER FLOODING ISSUES. FOR A MORE COMPLETE EXPLANATION OF THE ONGOING HYDROLOGY CONCERNS AND FORECASTS...PLEASE REFER TO THE LATEST HYDROLOGIC STATEMENT /MKERVSARX FGUS83/...HYDROLOGIC OUTLOOK /MKEESFARX FGUS73/ AND FLOOD STATEMENT /MKEFLSARX WGUS83/ PRODUCTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL 4 AM CDT MONDAY FOR WIZ017-WIZ029- WIZ032-WIZ033-WIZ034-WIZ041-WIZ042-WIZ043-WIZ044. MN...DENSE FOG ADVISORY UNTIL 4 AM CDT MONDAY FOR MNZ079-MNZ088. IA...NONE. && UPDATE...AJ SHORT/LONG TERM...HALBACH AVIATION...RRS/AJ HYDROLOGY...HALBACH
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE LA CROSSE WI 847 PM CDT SUN MAR 20 2011 IAZ008>011-018-019-029-030-MNZ086-087-094>096-WIZ053>055-061-211100- ALLAMAKEE-CHICKASAW-CLAYTON-CRAWFORD-DODGE-FAYETTE-FILLMORE-FLOYD- GRANT-HOUSTON-HOWARD-MITCHELL-MOWER-OLMSTED-RICHLAND-VERNON- WINNESHIEK- 847 PM CDT SUN MAR 20 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST MINNESOTA...NORTHEAST IOWA AND SOUTHWEST WISCONSIN. .DAY ONE...TONIGHT WARM TEMPERATURES AND RUNOFF FROM RECENT RAINFAL AND SNOWMELT WILL KEEP RIVER LEVELS ON THE RISE AT MANY LOCATIONS. STREAMS AND RIVERS COULD REACH OR EXCEED FLOOD STAGE IN SOME LOCATIONS TONIGHT AND INTO THE WORK WEEK. THOSE WITH RIVER INTERESTS SHOULD CONTINUE TO PAY CLOSE ATTENTION TO THE LATEST FORECASTS THROUGH THIS COMING WEEK. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY PRECIPITATION WILL RETURN TO THE REGION MONDAY NIGHT AND CONTINUE INTO WEDNESDAY. TEMPERATURES SUPPORT MOSTLY RAIN MONDAY NIGHT THROUGH TUESDAY EVENING...BUT SNOW OR A MIX OF RAIN...SNOW AND SLEET WOULD BE MORE LIKELY LATER TUESDAY NIGHT INTO WEDNESDAY. HEAVY RAINFALL IS ALSO POSSIBLE FROM LATE MONDAY NIGHT INTO TUESDAY NIGHT...WHICH WOULD RESULT IN MORE RISES ON AREA RIVERS AND STREAMS. IN ADDITION...SOME SNOW AND SLEET ACCUMULATION IS POSSIBLE LATER TUESDAY NIGHT INTO WEDNESDAY...MAINLY NORTH OF INTERSTATE 90. .SPOTTER INFORMATION STATEMENT... REPORTS OF RAINFALL OR ANY HIGH RIVER LEVELS WOULD BE APPRECIATED THE NEXT FEW DAYS. .EMERGENCY MANAGEMENT COORDINATION... A WEBINAR IS SCHEDULED FOR 11 AM MONDAY. THIS WEBINAR WILL ADDRESS THE HEAVY RAINFALL POTENTIAL CENTERED ON TUESDAY AND RESULTING FLOODING THREATS. MNZ079-088-WIZ017-029-032>034-041>044-211100- ADAMS-BUFFALO-CLARK-JACKSON-JUNEAU-LA CROSSE-MONROE-TAYLOR- TREMPEALEAU-WABASHA-WINONA- 847 PM CDT SUN MAR 20 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST MINNESOTA AND SOUTHWEST INTO CENTRAL WISCONSIN. .DAY ONE...TONIGHT THE COMBINATION OF LIGHT WINDS AND RECENT RAINFALL HAS RESULTED IN LOWERING VISIBILITIES ACROSS THE AREA. DUE TO EVEN LOWER VISIBILITIES EXPECTED...A DENSE FOG ADVISORY IS IN EFFECT TONIGHT. WARM TEMPERATURES AND RUNOFF FROM RECENT RAINFAL AND SNOWMELT WILL KEEP RIVER LEVELS ON THE RISE AT MANY LOCATIONS. STREAMS AND RIVERS COULD REACH OR EXCEED FLOOD STAGE IN SOME LOCATIONS TONIGHT AND INTO THE WORK WEEK. THOSE WITH RIVER INTERESTS SHOULD CONTINUE TO PAY CLOSE ATTENTION TO THE LATEST FORECASTS THROUGH THIS COMING WEEK. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY PRECIPITATION WILL RETURN TO THE REGION MONDAY NIGHT AND CONTINUE INTO WEDNESDAY. TEMPERATURES SUPPORT MOSTLY RAIN MONDAY NIGHT THROUGH TUESDAY EVENING...BUT SNOW OR A MIX OF RAIN...SNOW AND SLEET WOULD BE MORE LIKELY LATER TUESDAY NIGHT INTO WEDNESDAY. HEAVY RAINFALL IS ALSO POSSIBLE FROM LATE MONDAY NIGHT INTO TUESDAY NIGHT...WHICH WOULD RESULT IN MORE RISES ON AREA RIVERS AND STREAMS. IN ADDITION...SOME SNOW AND SLEET ACCUMULATION IS POSSIBLE LATER TUESDAY NIGHT INTO WEDNESDAY...MAINLY NORTH OF INTERSTATE 90. .SPOTTER INFORMATION STATEMENT... REPORTS OF RAINFALL OR ANY HIGH RIVER LEVELS WOULD BE APPRECIATED THE NEXT FEW DAYS. .EMERGENCY MANAGEMENT COORDINATION... A WEBINAR IS SCHEDULED FOR 11 AM MONDAY. THIS WEBINAR WILL ADDRESS THE HEAVY RAINFALL POTENTIAL CENTERED ON TUESDAY AND RESULTING FLOODING THREATS. DAS/RRS/AJ
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LA CROSSE WI 535 PM CDT SUN MAR 20 2011 MNZ079-086>088-094>096-210200- DODGE-FILLMORE-HOUSTON-MOWER-OLMSTED-WABASHA-WINONA- 535 PM CDT SUN MAR 20 2011 ...AREAS OF DENSE FOG EXPECTED THIS EVENING... AREAS OF DENSE FOG HAVE BEEN DEVELOPING IN THE WAKE OF THE RAIN TODAY. LOOK FOR THE DENSE FOG TO PERSIST UNTIL 8 PM WITH VISIBILITIES REDUCED TO ONE QUARTER OF A MILE OR LESS AT TIMES. AFTER 8 PM...A TROUGH OF LOW PRESSURE MOVING THROUGH WILL ALLOW THE FOG TO BEGIN DISSIPATING. IF TRAVELING THIS EVENING...BE PREPARED FOR DRASTICALLY REDUCED VISIBILITIES. AJ
The national radar mosaic for the moment the first event began.
8 flood. Local standard time, as filed.
The combination of rainfall and melting snow pushed the Black River at Black River Falls out of its banks. The river exceeded the flood stage from the 20th into the 23rd. The river crested about a foot and a half over the flood stage at 48.35 feet.
The combination of rainfall and melting snow pushed the Trempealeau River at Dodge out of its banks. The river exceeded the flood stage from the 21st into the 27th. The river crested almost four feet over the flood stage at 12.75 feet.
The combination of rainfall and melting snow pushed the Kickapoo River at Gays Mills out of its banks. The river exceeded the flood stage from the 22nd into the 27th. The river crested over a foot above the flood stage at 14.13 feet.
The combination of rainfall and melting snow pushed the Kickapoo River at Readstown out of its banks. The river exceeded the flood stage from the 22nd into the 25th. The river crested over a foot above the flood stage at 12.19 feet.
The combination of rainfall and melting snow pushed the Black River near Galesville out of its banks. The river exceeded the flood stage from the 23rd into the 25th. The river crested less than a foot over the flood stage at 12.88 feet.
The combination of rainfall and melting snow pushed the Kickapoo River at Viola out of its banks. The river exceeded the flood stage from the 23rd into the 24th. The river crested over a foot above the flood stage at 15.24 feet.
The combination of rainfall and melting snow pushed the Kickapoo River at Stueben out of its banks. The river exceeded the flood stage from the 23rd into the 28th. The river crested less than a foot over the flood stage at 12.51 feet.
The combination of rainfall and melting snow pushed the Kickapoo River at Soldiers Grove out of its banks. The river exceeded the flood stage from the 23rd into the 25th. The river crested less than a foot over the flood stage at 13.36 feet.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2011Every state in 2011This day in weather historyWarnings in Wisconsin, March 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 290981, 290631, 291131, 290986, 290983, 290984, 291135, 290988.