A stationary front was located along the South Dakota and Nebraska border, east of an area of surface low pressure over south central South Dakota. A tight surface pressure gradient set up across central and eastern North Dakota, and wind speeds just off the surface were measured at 60 to 70 mph.
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The episode as NWS FGF wrote it up.
A stationary front was located along the South Dakota and Nebraska border, east of an area of surface low pressure over south central South Dakota. A tight surface pressure gradient set up across central and eastern North Dakota, and wind speeds just off the surface were measured at 60 to 70 mph. Some of these 60 to 70 mph wind speeds were pushed down to the surface in central Ramsey county.
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 5, 8:38 PM CST, 30 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 938 PM CDT SAT MAY 5 2007 .UPDATE... WILL MAKE NO FURTHER FORECAST UPDATES THIS EVENING. WILL HAVE TO WATCH FOR FLASH FLOODING...ESPECIALLY ON THE SOUTHWEST FRINGE OF THE FA (SARGENT/RANSOM/BARNES) COUNTIES. SO FAR THE AXIS OF HEAVIEST PCPN HAS BEEN FROM ABERDEEN SOUTH DAKOTA UP TOWARD LAMOURE NORTH DAKOTA. KABR PICKED UP 2.80 INCHES OF RAIN IN ABOUT 40 MINUTES. THE PCPN TAPERS OFF TO ALMOST NOTHING JUST EAST OF THE RED RIVER VALLEY. CEILINGS HAVE CONTINUED TO RISE IN THIS AREA WITH MOST ASOS/AWOS LOCATIONS NOW REPORTING CLEAR SKIES BELOW 12000 FEET. CEILINGS HAVE ALSO BEEN RISING IN THE RED RIVER VALLEY EVEN WITH RAIN FALLING HEAVILY AT TIMES. THEREFORE AVIATION FORECASTING CONTINUES TO BE A CHALLENGE. WIND SPEEDS HAVE ALSO BEEN A CHALLENGE. THINK THE ESE WIND TRAJECTORY HAS KEPT THE STRONGEST GUSTS OUT OF THE FARGO/MOORHEAD AND GRAND FORKS/EGF AREAS. JUST TO THE EAST AND WEST OF THE VALLEY IT REMAINS QUITE WINDY. KFFM HAS HAD A FEW GUSTS TO 40 MPH...SO WILL KEEP AN EYE ON THIS AREA. && .PREV DISCUSSION... /ISSUED 617 PM CDT SAT MAY 5 2007/ UPDATE... WILL DO A QUICK UPDATE TO REMOVE THE HEAVY RAIN WORDING TO THE EAST OF THE RED RIVER VALLEY. CHANCES FOR RAIN CONTINUE TO LOOK BEST ALONG AND WEST OF THE VALLEY...ESPECIALLY FOR THE FLASH FLOOD WATCH AREA. PRECIPITATION CHANCES LOOK VERY GOOD...JUST NOT EXPECTING HEAVY RAINS TO THE EAST OF THE VALLEY. OTHERWISE... ALSO TAPERED BACK THE THUNDER MENTION IN THE EAST TOO...TO MORE SHOWERS WITH ISOLATED THUNDER. CONVECTIVE PARAMETERS ARE WEAK FOR OUR EASTERN FA...SO THUNDER WOULD BE PRETTY ISOLATED THERE. PREV DISCUSSION... /ISSUED 253 PM CDT SAT MAY 5 2007/ SHORT TERM... A VERY ACTIVE WEATHER PATTERN WILL CONTINUE FOR THE NEXT 36 HOURS...WITH LARGE UPPER LOW VERY SLOW TO MOVE. SFC LOW PRESSURE CONTINUES TO ORGANIZE IN NORTHEAST COLORADO...WITH WARM FRONT EXTENDING INTO SOUTHERN SD. DEWPOINTS IN WARM SECTOR HAVE RISING INTO THE MID 60S...ALONG WITH SEVERE WEATHER HERE. FURTHER NORTH IN OUR AREA...WE CONTINUE TO GET MOIST FEED MOVING UP THE VALLEY WITH SEVERAL SHORTWAVES AND MOIST/WARM ADVECTION AIDING MAINLY SHOWERS CURRENTLY. MODELS AREN/T IN GREAT AGREEMENT...AND LIKE GFS INITIAL DEPICTION OF QPF AND OVERALL EVOLUTION OF CONVECTIVE CLUSTERS OVERNIGHT SO WILL FOLLOW...ALTHOUGH WITH COMPLEX NATURE OF SYSTEM THIS SOLUTION IS NOT SET IN STONE EITHER. FOR TONIGHT...A VERY STRONG LOW LEVEL JET WILL INCREASE TO AROUND 70KT AT 850MB. THIS WILL PROVIDE AMPLE MOISTURE FOR SHOWERS AND THUNDERSTORMS...WITH THE BEST CHANCE ALONG AND WEST OF THE RED RIVER. INSTABILITY IS NOT THAT STRONG...ALTHOUGH SHOWALTERS WILL FALL TO AROUND -2C AND MUCAPES TO AROUND 500 J/KG IN THE FAR SW AFTER 03Z. THIS COULD BE ENOUGH FOR A FEW SEVERE STORMS LATER TONIGHT. THERE COULD ALSO BE STRONG WINDS MIXING TO THE SFC WITH ANY SHOWERS OR STORMS...SO WIND HEADLINES WILL ALSO NEED TO BE MONITORED. THE NEXT THREAT WILL BE HEAVY RAIN...WITH VERY STRONG MOISTURE ADVECTION AND THE BEST CONVERGENCE ALONG THE FAR SW AREA NEAR RANSOM/SARGENT COUNTIES. SOUNDINGS ALSO INDICATE A VERY LARGE WARM LAYER FOR EFFICIENT PRECIP PRODUCTION...SO THOUGH POTENTIAL FOR FLOOD HEADLINES WILL BE A CONCERN OVERNIGHT. ON SUNDAY...SFC BOUNDARY WILL REMAIN WEST OF THE AREA AND SOME INSTABILITY WILL REMAIN. THERE WILL LIKELY BE AN ONGOING MCS OVER THE VALLEY AT 12Z SUNDAY...THAT SHOULD PROGRESS NORTH AND EAST THROUGH THE MORNING. THERE WILL LIKELY BE SOME REGENERATION OF SHOWERS AND THUNDERSTORMS BY AFTERNOON MAINLY ALONG AND EAST OF THE VALLEY AND MORE HEAVY RAIN IS POSSIBLE. BY MONDAY...DEEP LAYERED DRYING AND A STABILIZING ATMOSPHERE WILL MOVE FROM WEST TO EAST. THIS SHOULD BRING AN END TO THE SHOWERS BY MONDAY AFTERNOON. TEMPS WILL WARM MORE THAN RECENT DAYS...WITH AT LEAST SOME SUNSHINE EXPECTED. TUESDAY SHOULD BE A NICE DAY WITH TEMPERATURES RISING ABOVE NORMAL AND PLENTY OF SUNSHINE EXPECTED. LONG TERM...(WED-SAT) A NICE START TO THE EXTENDED PERIOD ON WEDNESDAY MAY VERY WELL DETERIORATE FOR THE REMAINDER AS THE WESTERLIES TRY TO TRANSITION INTO A MORE SOUTHWEST FLOW AT 500 MB. THIS MAY TAKE TIME THOUGH...HIGH PRESSURE OVER WESTERN ONTARIO COULD VERY WELL ACT TO IMPEDE MOVEMENT OF MOISTURE AND THE NEXT LOW. ECMWF AND GFS DISAGREE ON DAY 6/7 WITH GFS TRACKING LOW SOUTH OF FARGO AS ECMWF VERSION PORTRAYS HIGH PRESSURE OVER GRAND FORKS. THUS CONFIDENCE IS LOW AND HAVE PAINTED SLIGHT CHANCE FOR THUNDER OVER MOST OF THE FORECAST AREA. CANADIAN/GFS ENSEMBLES INDICATING ABOVE NORMAL HEIGHT ANOMALIES LATE WEEK...BUMPED UP TEMPERATURES A COUPLE OF DEGREES. AVIATION... TOUGH TO TIME MVFR VERSUS IFR CONDITIONS RIGHT THROUGH SUN AFTERNOON. LOOK TO KEEP MOSTLY MARGINAL CIGS/VSBY WITH CATEGORICAL RAIN EXCEPT KBJI. EXPECT EVENING TEAM TO REFINE THUNDER CHANCES WITH NEXT TAF ISSUANCE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...FLASH FLOOD WATCH THROUGH SUNDAY EVENING FOR NDZ049-052. MN...NONE. && GODON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND FORKS ND 236 PM CDT SAT MAY 5 2007 MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024- 026>030-038-039-049-052>054-061945- 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- 236 PM CDT SAT MAY 5 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN NORTH DAKOTA...WEST CENTRAL AND NORTHWEST MINNESOTA. .DAY ONE...TONIGHT SIGNIFICANT RAINFALL IS POSSIBLE TONIGHT AND SUNDAY IN THE SOUTHERN RED RIVER VALLEY BASIN. THIS ADDITIONAL RAINFALL MAY CAUSE FLOODING IN THIS AREA. THERE IS ALSO A CHANCE FOR AN ISOLATED SEVERE THUNDERSTORM CONTAINING LARGE HAIL IN SOUTHEAST NORTH DAKOTA. STRONG WINDS ARE ALSO .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH SATURDAY THUNDERSTORM ARE POSSIBLE ON SUNDAY...AND ADDITIONAL HEAVY RAIN FALL WILL INCREASE THE THREAT FOR FLOODING IN THE SOUTHERN RED RIVER VALLEY. THE SLOW MOVING WEATHER SYSTEM WILL MOVE AWAY FROM THE REGION ON MONDAY...AND PROVIDE IMPROVING WEATHER CONDITIONS BY TUESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE REQUIRED FOR HEAVY RAIN REPORTS AND ISOLATED SEVERE WEATHER TONIGHT AND SUNDAY. DK
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
The wind gust was measured by a Davis weather station.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in North Dakota in 2007Every state in 2007This day in weather historyWarnings in North Dakota, May 2007
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: 34624.