Alert archive / North Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 311, NWS Grand Forks, ND

August 31, 2002Traill County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 31, 2002, 1:53 AM CDT for Traill County, North Dakota. It was in force for 37 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 31, 2002, 1:53 AM CDT (06:53 UTC)
Expired: Aug 31, 2002, 2:30 AM CDT
In force: 37 min
Issued by: NWS Grand Forks, ND
Area: Counties, with a storm outline in the text

County Traill County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 30 km from the middle of the area, began a volume at 06:53 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Aug 31, 2:15 AM CDT	Hail 1	Hillsboro, ND

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 6.9 hours before the alert went out and 284 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1932 J/kg
Mixed-layer CIN: -38 J/kg
Mixed-layer LCL: 1185 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 111 m²/s²
0-3 km storm-relative helicity: 212 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

766 
WUUS53 KFGF 310653
SVRFAR
NDC097-310730-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
152 AM CDT SAT AUG 31 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  TRAILL COUNTY IN SOUTHEAST NORTH DAKOTA.

* UNTIL 230 AM CDT.

* AT 143 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 4 MILES SOUTHWEST OF KELSO...OR ABOUT 31 MILES
  NORTHWEST OF FARGO...MOVEMENT WAS TO THE NORTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  HILLSBORO AT 155 AM AND
  CALEDONIA AT 210 AM.

REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES WITH LITTLE OR NO ADVANCE WARNING.

LAT...LON 4729 9721 4725 9704 4729 9687 4756 9690
54

NNNN

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Aug 30, 8:45 PM CDT, 5 hours 8 minutes earlier.

Area forecast discussion, Aug 30, 8:45 PM CDT, 5 hours 8 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
845 PM CDT FRI AUG 30 2002

MODELS APPEAR TO HAVE A NICE HANDLE ON THE LOW (925-850MB) LEVEL JET
CURRENTLY THOUGH MAYBE 10 KNOTS LOW. KMVX RADAR SHOWS 45-55 KNOTS AT
3-4 KFT AND SEEMS TO FIT THE MODELS DEPICTION THAT THE JET MAX IS
OVER EASTCENTRAL ND AND READY TO FEED SEVERE THUNDERSTORMS MOVING
NORTHEAST TOWARD DVL. NORTHERN COUNTIES TO BE UNDER GREATEST THREAT
OF HEAVY RAIN/SEVERE STORMS TONIGHT...UNFORTUNATELY THE AREA LEAST
ABLE TO HANDLE IT DUE TO ALREADY SATURATED SOILS. NOSE OF THETA-E
RIDGE IS ALSO FEEDING THOSE STORMS WHICH WILL ROTATE INTO NORTHEAST
ND AND STAY PRETTY MUCH ALL NIGHT. REST OF REGION MAY NOT HAVE MORE
THAN SCATTERED THUNDER TONIGHT BUT WILL LEAVE ZONES ALONE FOR NOW AS
THUNDERTORMS WEST OF ABR MAY GROW IN NUMBER IN HIGH MOISTURE. SOME
OF THE MODELS ALSO SUGGEST RESPECTABLE LOW LEVEL MOIST CONVERGENCE
OVER MUCH OF THE REGION TONIGHT.

.FGF...FLOOD WATCH ALL ZONES FOR TONIGHT AND SATURDAY.
GV

In the hours before

Local storm report, Aug 30, 10:57 PM CDT, 2 hours 56 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
1057 PM CDT FRI AUG 30 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1050 PM    FOREST RIVER              ND   .75 INCH HAIL
08/30/02   WALSH                          REPORTED BY LAW
                                          ENFORCEMENT.

DPORTER

Local storm report, Aug 31, 12:47 AM CDT, 1 hour 6 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
1247 AM CDT SAT AUG 31 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1245 AM    REYNOLDS                  ND   .75 INCH HAIL
08/31/02   TRAILL                         REPORTED BY FIRE
                                          DEPARTMENT.

DPORTER

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 30, 10:00 PM CDT	Severe Thunderstorm Warning	FGF	Grand Forks, Nelson	45 min
Aug 30, 10:45 PM CDT	Severe Thunderstorm Warning	FGF	Grand Forks, Walsh	45 min
Aug 30, 11:33 PM CDT	Flash Flood Warning	FGF	Grand Forks, Traill	8 hr
Aug 31, 12:51 AM CDT	Severe Thunderstorm Warning	FGF	Grand Forks	24 min
Aug 31, 6:37 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier, Towner	38 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 2002 Every severe thunderstorm warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.