Afternoon heating and cold temperatures aloft combined with an upper level disturbance to produce afternoon and early evening showers and thunderstorms. A few of the thunderstorms produced large hail as they tracked from the Pembina, North Dakota area down toward Argyle, Minnesota.
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 FGF wrote it up.
Afternoon heating and cold temperatures aloft combined with an upper level disturbance to produce afternoon and early evening showers and thunderstorms. A few of the thunderstorms produced large hail as they tracked from the Pembina, North Dakota area down toward Argyle, 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 Jun 21, 1:17 PM CST, 2 hours 38 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 217 PM CDT THU JUN 21 2012 .SHORT TERM... THE MAIN CHALLENGE WILL BE CONVECTION THROUGH THIS EVENING...THEN SHOWERS AND STORMS LATE FRI NIGHT INTO SAT NIGHT. MODELS ARE COMING AROUND TO A MORE NORTHERLY SOLUTION FOR SAT SYSTEM...AND THE GFS WAS THE FIRST TO INDICATE THIS POTENTIAL. WILL LEAN TOWARDS THE GFS SLIGHTLY FOR THIS REASON...BUT NO MAJOR DIFFERENCES OVERALL. FOR THE REST OF THIS AFTERNOON INTO THE EVENING...EXPECT SHOWERS AND THUNDERSTORMS IN THE NORTH WITH A SHORTWAVE AND AMPLE INSTABILITY/LIFT. CAN/T RULE OUT A FEW STORMS BECOMING MARGINALLY SEVERE WITH HAIL AND WIND THE MAIN THREATS. DEEP LAYERED SHEAR WILL ONLY BE AROUND 30KT IN THE NORTH...SO PULSE TYPE STORMS SHOULD BE THE RULE. THE THREAT FOR CONVECTION WILL DIMINISH AFTER SUNSET...ALTHOUGH A SHORTWAVE MOVING INTO THE NORTH AROUND 06Z COULD HELP A FEW SHOWERS AND STORMS LINGER UNTIL THEN. ON FRIDAY...A DRY DAY IS EXPECTED WITH RIDGING BUILDING IN AND WARMER TEMPS ALOFT. THERE IS A VERY LOW CHANCE FOR SOME SHOWERS AND STORMS IN THE FAR NORTHEAST...BUT FOR NOW WILL GO WITH A DRY FORECAST WITH NO SHORTWAVE ENERGY TO SPEAK OF. FOR FRI NIGHT...EXPECT MOISTURE TO INCREASE IN THE SOUTH WITH A LLJ DEVELOPING. THERE WILL BE SOME ELEVATED CAPE AND PWATS RISING OVER AN INCH BY 12Z SAT. WILL INCREASE SHOWER AND STORM CHANCES IN THE SOUTH OVERNIGHT. FOR SAT INTO SAT NIGHT...THERE WILL BE AN 850MB FRONT LIFTING INTO THE AREA. THERE WILL ALSO BE A LARGE INCREASE IN DEEP LAYERED MOISTURE WITH PWATS PROGGED AROUND 1.50 INCHES FOR ALL BUT THE FAR NORTH. WILL MENTION SHOWER AND THUNDER CHANCES IN ALL AREAS WITH THE BEST CHANCE IN THE SOUTH NEAR DEEPER INSTABILITY. CLOUDS MAY ALSO LIMIT HEATING AND TEMPS MAY HAVE TROUBLE GETTING INTO THE MID/UPPER 70S LIKE WE HAVE PROGGED. ON SUNDAY...SFC HIGH PRESSURE BUILDS IN FROM CANADA AND IT WILL BE A DRY AND MOSTLY SUNNY DAY WITH TEMPS NEAR TO SLIGHTLY BELOW NORMAL. .LONG TERM (SUN NITE THROUGH THURSDAY)... GFS/ECMWF IN AGREEMENT IN THEIR DEPICTION OF NORTHWEST FLOW AT BEGINNING OF EXTENDED PERIOD OVER THE FORECAST AREA. LONGWAVE RIDGE WILL QUICKLY BUILD IN FROM HIGH PLAINS AND THIS FEATURE WILL DOMINATE FOR A COUPLE OF DAYS BEFORE TRANSITIONING TO SOUTHWEST FLOW BY WEDNESDAY. THIS IS REFLECTED IN FORECAST BY A DRY MON/TUE BEFORE LOW POPS ARE INTRODUCED ON WEDNESDAY. SURFACE BOUNDARY LIKELY TO SWING THROUGH DURING THIS TIME WITH WEAK HIGH PRESSURE IN ITS WAKE FOR THURSDAY. TEMPS WILL RUN A FEW DEGREES ABOVE SEASONAL AVERAGE...TYPICAL TO THIS PATTERN. && .AVIATION... GUSTY WEST TO NORTHWEST WINDS WILL DIMINISH AROUND SUNSET...AND REMAIN LIGHT THROUGH FRIDAY AS HIGH PRESSURE MOVES INTO AREA. SEVERAL HOUR PERIOD OF VCTS INDICATED AT NORTHERNMOST TAF SITES AS CONVECTIVE ACTIVITY HAS ALREADY INITIATED FROM DEVILS LAKE THROUGH NORTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && DK/WJB
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND FORKS ND 602 AM CDT THU JUN 21 2012 MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024- 026>030-038-039-049-052>054-221115- 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-EDDY-NELSON-GRAND FORKS- GRIGGS-STEELE-TRAILL-BARNES-CASS-RANSOM-SARGENT-RICHLAND- WESTERN WALSH- 602 AM CDT THU JUN 21 2012 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 EXPECTED TO DEVELOP TOWARD MIDDAY CONTINUE TO DEVELOP THROUGH THE AFTERNOON AND EARLY EVENING. NO SEVERE WEATHER IS ANTICIPATED. DAYTIME HEATING COMBINED WITH AN UPPER LEVEL DISTURBANCE WILL AID IN THE DEVELOPMENT OF SCATTERED STORMS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THERE WILL BE A CHANCE FOR SHOWERS AND MAYBE A FEW THUNDERSTORMS LATER FRIDAY NIGHT INTO SATURDAY FOR SOUTHEASTERN NORTH DAKOTA INTO WEST CENTRAL MINNESOTA BUT NO SEVERE WEATHER IS EXPECTED. NO HAZARDOUS WEATHER IS ANTICIPATED THE REST OF THE PERIOD. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. DTR
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1232 PM CDT THU JUN 21 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0350 PM HAIL MAZA 48.39N 99.20W
06/20/2012 E0.75 INCH TOWNER ND PUBLIC
&&
WBARRETTPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
338 PM CDT THU JUN 21 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0350 PM HAIL MAZA 48.39N 99.20W
06/20/2012 E0.75 INCH TOWNER ND PUBLIC
0549 PM HAIL MICHIGAN 48.03N 98.12W
06/20/2012 E0.75 INCH NELSON ND CO-OP OBSERVER
0611 PM FUNNEL CLOUD 8 SSE PETERSBURG 47.90N 97.93W
06/20/2012 NELSON ND PUBLIC
AFTER STORMS WENT THROUGH A THIN FUNNEL CLOUD APPEARED ON
THE BACK EDGE OF THE CLOUD. IT APPEARED TO BE JUST SOUTH
OF PETERSBURG BUT WAS MORE DISTANT AND MORE CLOSELY
VIEWED OVER EAST CENTRAL ALDER TOWNSHIP. FROM A DISTANCE
THE FUNNEL APPEARED TO BE NEAR THE GROUND BUT AS VIEWED
FROM NEARBY THE FUNNEL REMAINED SEVERAL HUNDRED FEET
ABOVE THE TREE TOPS.
0630 PM HAIL 5 NE NASH 48.52N 97.44W
06/20/2012 E0.50 INCH WALSH ND TRAINED SPOTTER
SO MUCH HAIL FELL GROUND WAS COVERED.
0630 PM TSTM WND DMG 5 NE NASH 48.52N 97.44W
06/20/2012 WALSH ND TRAINED SPOTTER
APPROXIMATELY THE TOP 30 FEET OF 100 FOOT COTTONWOOD TREE
TWISTED OF AS GUST FRONT PUSHED THROUGH FARMSTEAD. NO
OTHER DAMAGE REPORTED.
0649 PM TORNADO 4 E KEMPTON 47.82N 97.53W
06/20/2012 F0 GRAND FORKS ND PUBLIC
THIS LONG... THIN AND ROPE LIKE TORNADO LAST FOR JUST A
COUPLE OF MINUTES AND TRACKED EASTWARD FOR ABOUT ONE
MILE... NEARLY TO THE AVON AND PLEASANT VIEW TOWNSHIP
LINE. NUMEROUS LARGE BRANCHES WERE KNOCKED DOWN IN A
FARMSTEAD SHELTER BELT AND A COUPLE OF LARGE TREE LIMBS
WERE SNAPPED OFF IN A FIELD SHELTERBELT. MAXIMUM WIDTH
ESTIMATED TO 20 YARDS AND PEAK WINDS ESTIMATED TO 70 MPH.
0702 PM TORNADO 7 ENE NORTHWOOD 47.77N 97.43W
06/20/2012 F1 GRAND FORKS ND NWS STORM SURVEY
THIS ROPE LIKE TORNADO LASTED FOR OVER 4 MINUTES AND
TRACKED DUE EAST FOR NEARLY TWO MILE IN THE FAR NORTHWEST
CORNER OF UNION TOWNSHIP. SEVERAL TREE TOPS WERE SNAPPED
IN FIELD SHELTER BELTS AND AT LEAST ONE TREE WAS UPROOTED
NEAR A FARMSTEAD SHELTERBELT. MAXIMUM WIDTH ESTIMATED TO
AROUND 30 YARDS AND PEAK WINDS ESTIMATED TO 90 MPH.
0725 PM HAIL 2 N THOMPSON 47.80N 97.11W
06/20/2012 E0.75 INCH GRAND FORKS ND TRAINED SPOTTER
ABOUT FOUR MINUTES OF PEA TO PENNY SIZED HAIL ALONG WITH
VERY STRONG WINDS.
&&
GGUSTSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
415 PM CDT THU JUN 21 2012
MNZ004-NDZ008-212215-
KITTSON MN-PEMBINA ND-
415 PM CDT THU JUN 21 2012
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN PEMBINA AND
NORTHWESTERN KITTSON COUNTIES UNTIL 515 PM CDT...
AT 411 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
THUNDERSTORM 6 MILES WEST OF PEMBINA...OR 40 MILES NORTH OF
GRAFTON...MOVING TO THE SOUTHEAST AT 20 MPH.
HAIL UP TO THE SIZE OF NICKELS IS EXPECTED WITH THE STORM.
THE STORM WILL BE NEAR...
PEMBINA AND NOYES AROUND 425 PM CDT.
ST. VINCENT AROUND 430 PM CDT.
HAMILTON AROUND 435 PM CDT.
HUMBOLDT AROUND 445 PM CDT.
FOR MOTORISTS ON INTERSTATE 29...THE STORM WILL BE BETWEEN...MILE
MARKER 215 AROUND 425 PM CDT...AND MILE MARKER 205 AROUND 445 PM
CDT...
BE PREPARED TO TAKE SHELTER IF THE STORMS INTENSIFY AND BECOME
SEVERE...OR A WARNING IS ISSUED BY THE NATIONAL WEATHER SERVICE.
LAT...LON 4873 9676 4868 9754 4899 9755 4901 9751
4901 9718
TIME...MOT...LOC 2116Z 319DEG 19KT 4898 9735
JARThe Fargo/Grand Forks radar (KMVX), 135 km away, was scanning. The volume nearest the first event began at 21:53 UTC.
1 thunderstorm wind, 1 hail. Local standard time, as filed.
Several four to six inch diameter tree branches were broken off trees in a farm yard.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2012Every state in 2012This day in weather historyWarnings in Minnesota, June 2012
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: 378959, 378368.