On the morning of the 22nd, a mesoscale convective vortex (MVC) tracked along the North and South Dakota border near Mobridge, South Dakota, into west central Minnesota. On the back edge of this MCV, a sharp clearing line was evident on satellite imagery and a wake low appeared in this region.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 FGF wrote it up.
On the morning of the 22nd, a mesoscale convective vortex (MVC) tracked along the North and South Dakota border near Mobridge, South Dakota, into west central Minnesota. On the back edge of this MCV, a sharp clearing line was evident on satellite imagery and a wake low appeared in this region. Gusty winds occurred near Jamestown, North Dakota, skipped over the Red River Valley, then appeared again over portions of west central Minnesota.
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 Grand Forks, ND wrote its last area forecast discussion before the first event at May 22, 5:56 AM CST, 2 hours 42 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 656 AM CDT SAT MAY 22 2010 .UPDATE... ISSUED A QUICK UPDATE THIS MORNING TO ACCOUNT FOR CURRENT RADAR RETURNS. THUNDERSTORMS ACROSS CENTRAL SOUTH DAKOTA EARLIER THIS MORNING HAVE COME TOGETHER TO FORM A MCS EAST OF ABERDEEN. NORTHERN EXTENT OF PRECIPITATION SHIELD HAS MOVED INTO SOUTHEAST NORTH DAKOTA...SO INCREASED POPS INTO THE LIKELY CATEGORY THROUGH 15 UTC. MODELS NOT RESOLVING MESOSCALE FEATURE WELL...SO DIFFICULT TO SAY HOW LONG MCS WILL HOLD TOGETHER. WOULD EXPECT IT TO DISSIPATE AND MOVE OUT OF THE FORECAST AREA BY LATE MORNING OR EARLY AFTERNOON GIVEN CURRENT TRENDS. && .AVIATION... EXPECT VFR CONDITIONS AT ALL TAF AIRFIELDS THROUGH AT LEAST 00 UTC WITH CEILINGS AT OR ABOVE 8000 KFT AGL. A VERY STRONG LOW-LEVEL JET WILL DEVELOP TODAY RESULTING IN GUSTY SOUTH-SOUTHEAST SURFACE WIND THIS AFTERNOON FROM 20 TO 25 KTS WITH GUSTS UP TO 30 KTS. STRONG TO SEVERE CONVECTION IS POSSIBLE FOR AIRFIELDS ALONG AND EAST OF THE RED RIVER VALLEY AFTER 00 UTC TONIGHT...BUT TIMING AND PLACEMENT CHALLENGES PRECLUDES A MORE THOROUGH MENTION IN CURRENT TAFS. FOR NOW...WILL COVER THREAT USING CB QUALIFIER AND AMEND AS NECESSARY AS MESOSCALE DETAILS BECOME MORE APPARENT. && .PREV DISCUSSION... /ISSUED 347 AM CDT SAT MAY 22 2010/ SHORT TERM...TODAY THROUGH MONDAY NIGHT PRIMARY FORECAST CHALLENGES INCLUDE PRECIPITATION CHANCES/LOCATION AND SEVERE CONVECTION THIS EVENING AND INTO EARLY SUNDAY. MODEL PRESSURE/HEIGHT AND THERMAL FIELDS ARE IN REASONABLE AGREEMENT... ALTHOUGH THE GFS/ECMWF ARE A BIT FASTER WITH SYSTEM TIMING COMPARED TO THE NAM...PLACING THE HIGHEST QPF TONIGHT FROM LISBON TO FARGO TO BEMIDJI. ALTHOUGH SYNOPTIC SCALE FEATURES ARE SIMILAR...IT WILL BE THE MESOSCALE DETAILS THAT DETERMINE WHEN AND WHERE THE STRONGEST CONVECTION OCCURS. AS SUCH...USED A MODEL BLEND FOR THIS FORECAST... BUT LEANED TOWARDS MORE SIMILAR GFS/ECMWF SOLUTIONS. ALL THAT BEING SAID...MODEL QPF PLACEMENT HAS BEEN POOR WITH CURRENT SHOWER ACTIVITY EAST OF BISMARCK...FROM DEVILS LAKE TO THE SOUTH DAKOTA BORDER. ONLY THE RUC APPEARS TO HAVE SOME GRASP ON CURRENT CONDITIONS IN WHICH PRECIPITATION IS CO-LOCATED WITH STRONGEST 850 TO 700 HPA WARM AIR ADVECTION. RUC WOULD SUGGEST SHOWERS AND SOME THUNDERSTORMS WILL SLOWLY DIMINISH AND WEAKEN THROUGH THE MORNING HOURS...SO WILL MAINTAIN CHANCE POPS FOR MOST OF THE FORECAST AREA TODAY. STRONG TO SEVERE STORMS ACROSS CENTRAL SOUTH DAKOTA WILL STAY SOUTH FOR NOW...RIDING ALONG THE NOSE OF A STRENGTHENING LOW-LEVEL JET. ALL MODELS SHOW THIS 40 TO 50 KNOT LOW-LEVEL JET MOVING INTO THE FORECAST AREA BY THIS AFTERNOON. AS A RESULT...SOUTH-SOUTHEAST SURFACE WINDS WILL BECOME STRONG FROM 20 TO 25 MPH WITH GUSTS TO 35 MPH. 700 HPA TEMPERATURES AROUND +12 CELSIUS SHOULD KEEP ATMOSPHERE CAPPED FOR MOST OF THE DAY...BUT STRONG 300 HPA JET SHOULD PROVIDE THE FORCING NECESSARY TO INITIATE CONVECTION AHEAD OF AND ALONG SURFACE BOUNDARY STARTING SOMETIME THIS EVENING. SURFACE DEW POINT TEMPERATURES WILL APPROACH 60 DEGREES IN THE WARM SECTOR WITH PRECIPITABLE WATER VALUES NEAR 1.5 INCHES. THE INFLUX OF LOW-LEVEL MOISTURE WILL HELP BRING ML CAPE VALUES INTO THE 1500 TO 2000 J/KG RANGE AND WITH 0 TO 6 KM BULK SHEAR VALUES FROM 40 TO 50 KTS...SEVERE CONVECTION IS ANTICIPATED. PER SPC DAY ONE CONVECTIVE OUTLOOK...ISOLATED LARGE HAIL AND TORNADOES WILL BE POSSIBLE BEFORE INDIVIDUAL STORMS LIKELY MERGE INTO LINEAR MCS INCREASING THE THREAT FOR DAMAGING WINDS. WILL ALSO NEED TO WATCH FOR FLASH FLOOD THREAT IF TRAINING CELLS BECOME AN ISSUE. THE BIG QUESTIONS LEFT UNANSWERED...TIMING AND LOCATION. AT THIS POINT...THE BIGGEST THREAT LOOKS TO BE FROM THE SOUTHERN VALLEY INTO ADJACENT PORTIONS OF WEST-CENTRAL AND NORTHWEST MINNESOTA LATER THIS EVENING AND OVERNIGHT. CONDITIONS WILL IMPROVE FROM WEST TO EAST SUNDAY AS DRIER AND MORE STABLE AIR MASS MOVE ACROSS THE REGION. HOWEVER...TEMPERATURES WILL REMAIN IN THE MID 70S TO NEAR 80 DEGREES. FOR MONDAY... ANOTHER SHORT-WAVE ROTATES THROUGH MOIST SOUTHWEST FLOW ALOFT FOR THE NEXT ROUND OF CONVECTION. MODEL DIFFERENCES ABOUND...SO KEPT CHANCE POPS FOR NOW UNTIL DETAILS CAN BE IRONED OUT. LONG TERM...TUESDAY THROUGH FRIDAY THE MAIN CHALLENGES IN THE LONG TERM ARE PCPN CHANCES AND WINDS. THE MODELS ARE IN DECENT AGREEMENT...WITH THE ECMWF BEING A LITTLE WARMER THAN THE GFS AND GEM. LEANED ON A BLEND OF THE ECMWF/GFS/GEM. THE GFS/ECMWF/GEM/DGEX ALL INDICATE THAT A MONTANA HIGH PLAINS LOW PRESSURE SYSTEM WILL PUSH NORTH INTO SASKATCHEWAN ON TUESDAY. ITS ASSOCIATED DRY SLOT SHOULD SWEEP NORTH INTO THE NORTHERN PLAINS...AT LEAST ACROSS AND WEST OF THE RED RIVER VALLEY. THE SOUNDINGS LOOKED VERY DRY AND WELL MIXED...SO INCREASED THE WINDS...DECREASED SKY COVER...AND DECREASED RELATIVE HUMIDITIES. IT LOOKS LIKE PCPN IS POSSIBLE TUESDAY...ESPECIALLY EAST OF THE VALLEY. STILL LEFT SOME PCPN CHANCES ACROSS THE VALLEY TO ACCOUNT FOR UNCERTAINTY IN CASE THE FUTURE MODELS CHANGE THE TIMING OF THE SYSTEM. THE MODELS ARE ALL IN PRETTY GOOD AGREEMENT FOR HAVING HIGH PRESSURE OVER EASTERN ND AND NORTHWESTERN MN WEDNESDAY...WHICH SHOULD HELP KEEP THINGS DRY. HOWEVER...INHERITED PCPN CHANCES FROM THE PREVIOUS FORECAST. THE GFS/ECMWF/DGEX DO INDICATE SOME PCPN TO THE SOUTH AND EAST...SO DECIDED TO TREND THE PCPN CHANCES DOWN A BIT...BUT NOT COMPLETELY REMOVE THEM JUST YET. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && ROGERS/GROCHOCINSKI
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND FORKS ND 523 AM CDT SAT MAY 22 2010 MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024- 026>030-038-039-049-052>054-231030- WEST POLK-NORMAN-CLAY-KITTSON-ROSEAU-LAKE OF THE WOODS- WEST MARSHALL-EAST MARSHALL-NORTH BELTRAMI-PENNINGTON-RED LAKE- EAST POLK-NORTH CLEARWATER-SOUTH BELTRAMI-MAHNOMEN- SOUTH CLEARWATER-HUBBARD-WEST BECKER-EAST BECKER-WILKIN- WEST OTTER TAIL-EAST OTTER TAIL-WADENA-GRANT-TOWNER-CAVALIER- PEMBINA-BENSON-RAMSEY-EASTERN WALSH COUNTY-EDDY-NELSON- GRAND FORKS-GRIGGS-STEELE-TRAILL-BARNES-CASS-RANSOM-SARGENT- RICHLAND-WESTERN WALSH COUNTY- 523 AM CDT SAT MAY 22 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN NORTH DAKOTA...WEST CENTRAL AND NORTHWEST MINNESOTA. .DAY ONE...TODAY AND TONIGHT SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS MORNING AND AFTERNOON. ANY ACCUMULATION SHOULD BE LESS THAN ONE QUARTER OF AN INCH. IN ADDITION...STRONG SOUTH-SOUTHEAST WINDS WILL DEVELOP THIS AFTERNOON WITH SUSTAINED SPEEDS FROM 20 TO 30 MPH AND GUSTS UP TO 35 MPH. SIGNIFICANT WAVE ACTION IS POSSIBLE ON LARGE AREA LAKES THROUGHOUT THE DAY. STRONG TO SEVERE THUNDERSTORMS WILL DEVELOP THIS EVENING AND OVERNIGHT AS A WELL-DEFINED COLD FRONT MOVES ACROSS THE REGION. THE EXACT TIMING AND LOCATION OF THE STRONGEST STORMS IS STILL UNCERTAIN...BUT THE GREATEST THREAT EXISTS ACROSS SOUTHEAST NORTH DAKOTA AND ADJACENT PORTIONS OF WEST-CENTRAL AND NORTHWEST MINNESOTA BEGINNING THIS EVENING. LARGE HAIL...DAMAGING WIND AND HEAVY RAIN WILL BE POSSIBLE AS WELL AS ISOLATED TORNADOES. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY SHOWERS AND THUNDERSTORMS WILL DISSIPATE FROM WEST TO EAST THROUGH THE DAY SUNDAY BEFORE A RETURN TO UNSETTLED WEATHER AND THE NEXT THREAT FOR SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE SEVERE...MONDAY INTO EARLY TUESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL LIKELY BE REQUIRED THIS EVENING AND OVERNIGHT. SPOTTERS ARE ENCOURAGED TO PROVIDE SEVERE WEATHER REPORTS TO THE NEAREST NATIONAL WEATHER SERVICE OFFICE. ROGERS
The national radar mosaic for the moment the first event began.
3 high wind. Local standard time, as filed.
A MNDOT RWIS sensor near Ottertail measured wind gusts of 58 mph.
The Hubbard County emergency manager reported portions of the southern half of Hubbard County had power lines down and two power poles snapped in half.
Power poles and trees were blown down near Sebeka and Nimrod.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2010Every state in 2010This day in weather historyWarnings in Minnesota, May 2010
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: 221246, 221247, 221248.