The combination of melting snow and some rainfall pushed some northeast Iowa rivers out of their banks during the latter half 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 pushed some northeast Iowa rivers out of their banks during the latter half 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 21, 2:39 AM CST, 4 hours 6 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 339 AM CDT MON MAR 21 2011 .SHORT TERM...THROUGH WEDNESDAY NIGHT MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES...TYPES AND AMOUNTS FROM TONIGHT THROUGH WEDNESDAY. SURFACE ANALYSIS THIS MORNING SHOWS AN AREA OF LOW PRESSURE OVER THE MINNESOTA ARROWHEAD. THE COLD FRONT WITH THE LOW STRETCHES SOUTHEAST FROM THE LOW ACROSS LAKE MICHIGAN AND THEN BACK ACROSS ILLINOIS AND NORTHERN MISSOURI TO ANOTHER LOW FORMING OVER EASTERN COLORADO. WEAK UPPER LEVEL RIDGING WILL BE OVER THE REGION TODAY BUT THIS WILL QUICKLY SLIDE OFF TO THE EAST TONIGHT ALLOWING SOUTHWEST FLOW TO RETURN. THE SURFACE FRONT WILL BECOME STATIONARY TO THE SOUTH OF THE AREA TODAY AND THEN QUICKLY BEGIN TO LIFT BACK TO THE NORTH TONIGHT AS THE FLOW ALOFT BECOMES SOUTHWEST. THE 21.00Z GFS INDICATES STRONG LOW LEVEL WARM AIR ADVECTION WILL SPREAD ACROSS THE REGION TONIGHT IN THE SOUTHWEST FLOW. THE RESULTING ISENTROPIC UP GLIDE WILL RANGE FROM 3 TO 7 UBAR/S ON THE 295K SURFACE AND WITH LITTLE DRYING EXPECTED TODAY...IT WILL TAKE VERY LITTLE LIFT TO ALLOW SATURATION TO OCCUR. THE GFS AND BOTH THE 20.12Z AND 21.00Z ECMWF QUICKLY DEVELOP SHOWERS ALONG AND NORTH OF THE FRONT WITH THESE SPREADING INTO THE AREA MAINLY SOUTH OF THE IOWA/MINNESOTA BORDER THIS EVENING. RAISED THE RAIN CHANCES WITH 20 ALONG I94 TO 60 IN THE SOUTHWEST. THE ISENTROPIC UP GLIDE WILL BE THE STRONGEST AFTER 06Z AND WITH SOME WEAK MOISTURE TRANSPORT INTO THE AREA ON THIS SURFACE...WENT AHEAD AND RAISED THE PRECIPITATION CHANCES WITH MOST OF THE AREA BETWEEN 70 AND 90 PERCENT. MOST OF THE AREA SHOULD REMAIN WARM ENOUGH FOR JUST RAIN BUT DID MAINTAIN THE CHANCE OF A RAIN/SNOW MIX FOR AREAS NORTH OF I94. ALSO ADDED SOME THUNDER CHANCES ACROSS THE SOUTHWEST SECTIONS WHERE THE GFS SHOWS UP TO 250 J/KG OF ELEVATED CAPE ABOVE 1 KM. THE MEAN UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST TUESDAY WITH AN UPPER LEVEL LOW EXPECTED TO BE OVER MONTANA. A SHORT WAVE TROUGH IS EXPECTED TO ROTATE AROUND THE LOW AND MOVE ACROSS THE REGION TUESDAY AFTERNOON AND EVENING. THIS WAVE IS EXPECTED TO PUSH UP TO 30 PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER ACROSS THE REGION. THE ISENTROPIC UP GLIDE WILL INCREASE AHEAD OF THE WAVE AND SHOULD BE ON THE ORDER OF 10 UBAR/S ON THE 295K SURFACE. THE MOISTURE TRANSPORT WILL ALSO INCREASE AND SHOULD BE POINTED RIGHT INTO THE AREA DURING THE AFTERNOON. THE GFS SHOWS A GOOD FRONTOGENESIS SIGNAL DEVELOPING DURING THE AFTERNOON BUT THEN LOSES IT DURING THE EVENING WHERE AS THE 21.00Z NAM CONTINUES IS FROM CENTRAL MINNESOTA TO SOUTHEAST WISCONSIN...ESPECIALLY IN THE 850-700 MB LAYER. THIS SHOULD RESULT IN WIDESPREAD PRECIPITATION THROUGH THE ENTIRE DAY TUESDAY FOR THE ENTIRE AREA WITH THUNDER REMAINING A POSSIBILITY ACROSS THE SOUTHWEST HALF. AS THE SHORT WAVE TROUGH PASSES BY ALOFT...THE LOW OVER COLORADO WILL BE MOVING ALONG THE FRONT AND WILL START TO BRING COLDER AIR INTO THE REGION. THE BEST ISENTROPIC UP GLIDE WILL BE TRANSLATING EAST OF THE AREA...BUT THE GFS STILL SUGGESTS UP TO 4 UBAR/S CONTINUING THROUGH TUESDAY NIGHT. THE GFS REDEVELOPS THE FRONTOGENESIS SIGNAL DURING THE OVERNIGHT FROM CENTRAL MINNESOTA TO SOUTHEAST WISCONSIN AND IS THE STRONGEST WITH IT IN THE PREFERRED 500-700 MB LAYER. THERE IS ALSO EXPECTED TO BE GOOD FN VECTOR CONVERGENCE ASSOCIATED WITH THE FRONTOGENESIS WITH THE NAM SHOWING THIS TO BE STRONGEST IN THE 750-650 MB LAYER. THE PRECIPITATION TYPE WILL BE TRANSITIONING FROM RAIN OR THE RAIN/SNOW MIX TO ALL SNOW...ESPECIALLY ACROSS THE NORTH. THE UNKNOWN IS HOW MANY OTHER PRECIPITATION TYPES WILL ALSO OCCUR. THE THERMAL PROFILES FROM BOTH THE NAM AND GFS NO LONGER SUPPORT MUCH SLEET BUT CAN NOT TOTALLY RULE IT OUT. SO DID NOT REMOVE THE SLEET BUT DID LOWER THE PROBABILITIES SOME FROM THE PREVIOUS FORECAST. THERE COULD ALSO BE A SHORT PERIOD OF SOME FREEZING RAIN OR SOME FREEZING DRIZZLE IF THE NAM IS CORRECT AND THE ICE CRYSTAL CLOUDS ARE LOST FOR A WHILE. WENT AHEAD AND ADDED SOME LOW PROBABILITIES FOR FREEZING DRIZZLE ACROSS THE NORTH TO COVER THIS POSSIBILITY. WITH THE AMPLE FORCING...A PERIOD OF SOME HEAVY SNOW LOOKS TO BE POSSIBLE ACROSS THE NORTH AS WELL WITH ACCUMULATIONS AROUND 6 INCHES POSSIBLE FOR AREAS NORTH OF HIGHWAY 29. THE FORCING WILL START TO WEAKEN AND MOVE OFF TO THE EAST WEDNESDAY BUT STILL SHOULD BE STRONG ENOUGH TO PRODUCE MORE ACCUMULATING SNOWS ACROSS THE NORTH. WILL ISSUE A WINTER STORM WATCH WITH THIS PACKAGE FOR TAYLOR AND CLARK COUNTIES. .LONG TERM...THURSDAY THROUGH SUNDAY ANOTHER SYSTEM LOOKS TO CROSS THE CENTRAL PART OF THE COUNTRY LATE IN THE WEEK. IT APPEARS THE BULK OF THE PRECIPITATION FROM THIS SYSTEM SHOULD PASS BY TO THE SOUTH BUT COULD STILL SEE THE NORTHERN EDGE OF THE PRECIPITATION BRUSH PARTS OF THE AREA THURSDAY NIGHT AND FRIDAY. DIFFERENCES THEN SHOW UP FOR THE WEEKEND WITH THE GFS SHOWING A STRONG SURFACE LOW MOVING FROM KANSAS TOWARD THE OHIO RIVER VALLEY WITH LOTS OF PRECIPITATION ON THE NORTH SIDE OF THE LOW TRACKING ACROSS THE REGION. THE ECMWF WHILE SHOWING A LITTLE BIT OF PRECIPITATION FOR THE REGION SUGGESTS A CANADIAN HIGH WILL BE THE DOMINANT FEATURE FOR THE REGION. USED THE MODEL CONSENSUS GRIDS FOR NOW UNTIL THERE IS BETTER AGREEMENT ON WHICH SOLUTION IS CORRECT. && .AVIATION... LIFR TO MVFR STRATUS OVER THE TAF SITES WILL BE SLOWER TO SCATTER OUT THIS MORNING. GRADUAL IMPROVEMENT IS EXPECTED AS DRIER AIR ADVECTS INTO THE AREA. VFR CONDITIONS ARE THEN EXPECTED BY LATER THIS MORNING AND WILL CONTINUE THROUGH THIS AFTERNOON AS HIGH PRESSURE MOVES ACROSS THE TAF SITES. THE PERIOD OF VFR CONDITIONS LOOKS TO BE SHORT-LIVED AS A WARM FRONT OVER THE CENTRAL PLAINS LIFTS NORTH. PLENTIFUL MOISTURE RETURNING NORTH OVER THE FRONT WILL FIRST BE NOTICED BY THICKENING ALTOSTRATUS THIS EVENING...WHICH COULD EVEN PRODUCE SOME LIGHT RAIN AT KRST. FURTHER LOWERING OF THE CEILINGS IS EXPECTED AFTER MIDNIGHT WITH MVFR AND EVEN IFR CONDITIONS POSSIBLE BETWEEN 09-12Z TUESDAY. RAIN IS LIKELY TOO AFTER MIDNIGHT...WHICH COULD BE ENOUGH TO PRODUCE SOME MVFR BR DURING THAT 09-12Z PERIOD. PLAN ON IFR TO MVFR CONDITIONS FOR TUESDAY AS WELL...ALONG WITH MORE RAIN. && .HYDROLOGY... THE STREAMS QUICKLY JUMPED SUNDAY FROM THE RAIN THAT FELL ACROSS THE AREA. EXPECTING ANOTHER RISE TO OCCUR FROM MONDAY NIGHT THROUGH TUESDAY NIGHT WITH THE ADDITIONAL PRECIPITATION THAT IS EXPECTED OCCUR. CURRENT INDICATIONS ARE THAT AMOUNTS OF 1.25 TO 1.75 INCHES WITH LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE. THIS SHOULD PUSH QUITE A FEW OF THE RIVERS HIGHER AND POSSIBLY OUT OF THEIR BANKS. AT THIS TIME...EXPECT ANY FLOODING TO PRIMARILY BE LIMITED TO THE RIVERS AND NOT PLANNING TO ISSUE A FLOOD WATCH. 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...WINTER STORM WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY EVENING FOR WIZ017-WIZ029. MN...NONE. IA...NONE. && SHORT/LONG TERM...04 AVIATION...DAS/AJ HYDROLOGY...04
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LA CROSSE WI 557 AM CDT MON MAR 21 2011 IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ032>034-041>044- 053>055-061-221100- ADAMS-ALLAMAKEE-BUFFALO-CHICKASAW-CLAYTON-CRAWFORD-DODGE-FAYETTE- FILLMORE-FLOYD-GRANT-HOUSTON-HOWARD-JACKSON-JUNEAU-LA CROSSE- MITCHELL-MONROE-MOWER-OLMSTED-RICHLAND-TREMPEALEAU-VERNON-WABASHA- WINNESHIEK-WINONA- 557 AM CDT MON MAR 21 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST MINNESOTA...NORTHEAST IOWA AND SOUTHWEST INTO CENTRAL WISCONSIN. .DAY ONE...TODAY AND TONIGHT WARM TEMPERATURES AND RUNOFF FROM RECENT RAINFALL AND SNOWMELT WILL KEEP RIVER LEVELS ON THE RISE AT MANY LOCATIONS. STREAMS AND RIVERS COULD REACH OR EXCEED FLOOD STAGE IN SOME LOCATIONS OVER THE NEXT FEW DAYS. THOSE WITH RIVER INTERESTS SHOULD CONTINUE TO PAY CLOSE ATTENTION TO THE LATEST FORECASTS THROUGH THIS COMING WEEK. THERE WILL BE A CHANCE FOR SOME THUNDERSTORMS TONIGHT FOR AREAS SOUTH OF A LINE FROM DODGE CENTER MINNESOTA TO BOSCOBEL WISCONSIN. OCCASIONAL HEAVY RAIN...SMALL HAIL AND LIGHTNING LOOK TO BE THE MAIN THREATS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY PRECIPITATION WILL CONTINUE INTO WEDNESDAY. TEMPERATURES WILL BE WARM ENOUGH FOR MAINLY RAIN TO FALL THROUGH TUESDAY EVENING... BUT SNOW OR A MIXTURE OF RAIN...SNOW WILL BE LIKELY LATER TUESDAY NIGHT INTO WEDNESDAY. SOME SLEET COULD ALSO FALL TUESDAY NIGHT FOR AREAS NORTH OF INTERSTATE 90. SOME THUNDERSTORMS WITH SMALL HAIL WILL CONTINUE TO BE POSSIBLE TUESDAY FOR AREAS SOUTH OF THE DODGE CENTER MINNESOTA TO BOSCOBEL WISCONSIN LINE. HEAVY RAINFALL IS ALSO POSSIBLE TUESDAY 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. THIS WEBINAR WILL ADDRESS THE HEAVY RAINFALL POTENTIAL FROM TONIGHT INTO TUESDAY NIGHT AND THE RESULTING FLOODING THREATS. IT WILL ALSO ADDRESS THE WINTER STORM POTENTIAL ACROSS NORTH CENTRAL WISCONSIN. WIZ017-029-221100- CLARK-TAYLOR- 557 AM CDT MON MAR 21 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL WISCONSIN. .DAY ONE...TODAY AND TONIGHT WARM TEMPERATURES AND RUNOFF FROM RECENT RAINFALL AND SNOWMELT WILL KEEP RIVER LEVELS ON THE RISE AT MANY LOCATIONS. STREAMS AND RIVERS COULD REACH OR EXCEED FLOOD STAGE IN SOME LOCATIONS OVER THE NEXT FEW DAYS. THOSE WITH RIVER INTERESTS SHOULD CONTINUE TO PAY CLOSE ATTENTION TO THE LATEST FORECASTS THROUGH THIS COMING WEEK. RAIN SHOWERS WILL MOVE INTO THE AREA AFTER MIDNIGHT. TEMPERATURES COULD GET COLD ENOUGH FOR SOME SNOW TO MIX IN WITH THE RAIN. NO SNOW ACCUMULATION IS EXPECTED TO OCCUR. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY A MIXTURE OF RAIN AND SNOW WILL CONTINUE TUESDAY BEFORE CHANGING OVER TO SNOW TUESDAY NIGHT. A PERIOD OF HEAVY SNOW LOOKS TO BE POSSIBLE TUESDAY NIGHT. MORE SNOW IS EXPECTED TO FALL WEDNESDAY BEFORE TAPERING OFF WEDNESDAY NIGHT. ACCUMULATIONS OF 6 INCHES OR MORE ARE POSSIBLE AND A WINTER STORM WATCH IS IN EFFECT FOR TUESDAY NIGHT AND WEDNESDAY. SOME SLEET OR FREEZING DRIZZLE COULD ALSO FALL FOR A WHILE TUESDAY NIGHT INTO WEDNESDAY MORNING BUT LITTLE IF ANY ICE ACCUMULATION IS EXPECTED. .SPOTTER INFORMATION STATEMENT... REPORTS OF SNOW ACCUMULATIONS...RAINFALL OR ANY HIGH RIVER LEVELS WOULD BE APPRECIATED THE NEXT FEW DAYS. .EMERGENCY MANAGEMENT COORDINATION... A WEBINAR IS SCHEDULED FOR 11 AM. THIS WEBINAR WILL ADDRESS THE HEAVY RAINFALL POTENTIAL FROM TONIGHT INTO TUESDAY NIGHT AND THE RESULTING FLOODING THREATS. IT WILL ALSO ADDRESS THE WINTER STORM POTENTIAL ACROSS NORTH CENTRAL WISCONSIN. 04
The national radar mosaic for the moment the first event began.
3 flood. Local standard time, as filed.
The combination of rainfall and melting snow pushed the Upper Iowa River near Dorchester out of its banks. The river exceeded the flood stage on the 21st and twice on the 24th. The highest crest was around a quarter of a foot above the flood stage at 14.22 feet.
The combination of rainfall and melting snow pushed the Cedar River at Charles City out of its banks. The river exceeded the flood stage from 21st into the 22nd and again from 23rd into the 25th. The highest crest was over three feet above the flood stage at 15.41 feet.
The combination of rainfall and melting snow pushed the Turkey River at Elkader out of its banks. The river exceeded the flood stage for a short period on the 23rd. The river crested less than a quarter of a foot over the flood stage at 12.14 feet.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2011Every state in 2011This day in weather historyWarnings in Iowa, 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: 290628, 290627, 290629.