Alert archive / North Dakota / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 192, NWS Grand Forks, ND
NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 31, 1997, 11:18 PM CDT for Cass County, North Dakota. It was in force for 42 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Aug 31, 1997, 11:18 PM CDT (04:18 UTC)
- Expired
- Sep 1, 1997, 12:00 AM CDT
- In force
- 42 min
- Issued by
- NWS Grand Forks, ND
- Area
- Whole counties
County Cass County, ND
The radar
The Fargo/Grand Forks radar (KMVX), 66 km from the middle of the area, began a volume at 04:16 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, 11:31 PM CDT | Hail 0.75 | Chaffee, 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.
The nearest sounding before it
Aberdeen, SD (KABR), launched 00:00Z, 4.3 hours before the alert went out and 243 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.
- Mixed-layer CAPE
- 1215 J/kg
- Mixed-layer CIN
- -223 J/kg
- Mixed-layer LCL
- 1591 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 89 m²/s²
- 0-3 km storm-relative helicity
- 191 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KFAR 010420 RRA SVRFAR NDC017-010500- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1118 PM CDT SUN AUG 31 1997 THE NATIONAL WEATHER SERVICE IN EASTERN ND/GRAND FORKS HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL MIDNIGHT CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN SOUTHEAST NORTH DAKOTA ...CASS COUNTY AT 1117 PM CDT...DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS EXTENDING FROM 5 MILES NORTHEAST OF TOWER CITY...TO JUST SOUTHWEST OF ALICE...OR FROM 20 MILES NORTHEAST OF VALLEY CITY...TO 25 MILES SOUTHEAST OF VALLEY CITY. THIS LINE OF THUNDERSTORMS WAS MOVING EAST AT 25 MPH...AND WILL AFFECT THE TOWNS OF AMENIA...CASSELTON AND CHAFFE. WHEN THUNDERSTORMS ARE OCCURRING...MOVE INTO A STRONG BUILDING. DON'T USE TELEPHONES OR ELECTRICAL APPLIANCES AND STAY AWAY FROM WINDOWS. RA
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 31, 8:57 PM CDT, 2 hours 21 minutes earlier.
Area forecast discussion, Aug 31, 8:57 PM CDT, 2 hours 21 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 855 PM CDT SUN AUG 31 1997 FORECAST PROBLEM FOR TONIGHT IS PCPN AND SVR POTENTIAL. SUPERCELLS CONTINUE TO DEVELOP JUST TO THE W OF THE CWFA AND TRY TO MOVE INTO FAR W COUNTIES. ALREADY CANCELLED TOR WATCH FOR NE ND AS TSRA TRAIN ECHOING ALONG WARM FRONT WHICH EXTENDS FROM BIS TO JMS TO FAR. POTENTIAL CONTINUES TO EXIST OVERNIGHT FOR LARGE HAIL...DAMAGING WIND...TORNADOS AND TORRENTIAL RAINFALL ALONG THIS FRONT. MODELS ALSO BRING SHORTWAVE WITH SFC COLD FRONT INTO CWFA BY 12Z. WITH 300 MB JET AND LLJ SETTING UP THIS EVENING...WILL NEED TO KEEP EYE OUT FOR SVR OVERNIGHT AS WEJLL. MOST OF TEMPS LOOK OK WITH ONLY MINOR CHANGES NEEDED. ND ZFP ALREADY UPDATED FOR WATCH CANCELLATION...WILL WAIT UNTIL AFTER 10 PM TO UPDATE AGAIN AFTER REST OF WATCH EXPIRES. WILL UPDATE MN ZFP SHORTLY. NG
In the hours before
Special weather statement, Aug 31, 10:16 PM CDT, 1 hour 2 minutes before
NDZ006>008-014>016-024-026>030-038-039-049-052-053-010415- SPECIAL WEATHER STATEMENT...CORRECTED NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1016 PM CDT SUN AUG 31 1997 ...TORNADO WATCH ALLOWED TO EXPIRE FOR EASTERN NORTH DAKOTA... THE TORNADO WATCH THAT WAS IN EFFECT FOR EASTERN NORTH DAKOTA HAS BEEN ALLOWED TO EXPIRE. A WARM FRONT EXTENDING FROM BISMARCK TO JAMESTOWN TO FARGO WILL CONTINUE TO PROVIDE THE FOCUS FOR THUNDERSTORM DEVELOPMENT OVERNIGHT. AS THE STORMS MOVE EAST ALONG THE WARM FRONT...ISOLATED OCCURRANCES OF LARGE HAIL...DAMAGING WINDS AND TORNADOS REMAIN POSSIBLE. VERY HEAVY RAINFALL CAN ALSO BE EXPECTED FROM THESE STORMS. NG
Special weather statement, Aug 31, 10:17 PM CDT, 1 hour 1 minute before
NDZ006>008-014>016-024-026>030-038-039-049-052-053-010415- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1016 PM CDT SUN AUG 31 1997 ...TORNADO WATCH ALLOWED TO EXPIRE FOR EASTERN NORTH DAKOTA... THE TORNADO WATCH THAT WAS IN EFFECT FOR EASTERN NORTH DAKOTA HAS BEEN ALLOWED TO EXPIRE. A WARM FRONT EXTENDING FROM BISMARCK TO JAMESTOWN TO FARGO WILL CONTINUE TO PROVIDE THE FOCUS FOR THUNDERSTORM DEVELOPMENT OVERNIGHT. AS THE STORMS MOVE EAST ALONG THE WARM FRONT...LARGE HAIL...DAMAGING WINDS AND TORNADOS REMAIN POSSIBLE ALONG WITH VERY HEAVY RAINFALL FROM THESE STORMS. NG
Special weather statement, Aug 31, 10:20 PM CDT, 58 minutes before
NDZ006>008-014>016-024-026>030-038-039-049-052-053-010415- SPECIAL WEATHER STATEMENT...CORRECTED NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1016 PM CDT SUN AUG 31 1997 ...TORNADO WATCH ALLOWED TO EXPIRE FOR EASTERN NORTH DAKOTA... THE TORNADO WATCH THAT WAS IN EFFECT FOR EASTERN NORTH DAKOTA HAS BEEN ALLOWED TO EXPIRE. A WARM FRONT EXTENDING FROM BISMARCK TO JAMESTOWN TO FARGO WILL CONTINUE TO PROVIDE THE FOCUS FOR THUNDERSTORM DEVELOPMENT OVERNIGHT. AS THE STORMS MOVE EAST ALONG THE WARM FRONT...ISOLATED OCCURRANCES OF LARGE HAIL...DAMAGING WINDS AND TORNADOS REMAIN POSSIBLE. VERY HEAVY RAINFALL CAN ALSO BE EXPECTED FROM THESE STORMS. NG
Special weather statement, Aug 31, 10:45 PM CDT, 33 minutes before
MNZ001-002-013>015-022-NDZ027-029-030-010645- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1045 PM CDT SUN AUG 31 1997 ...GUSTY WINDS EXPECTED TO CONTINUE OVER PARTS OF NORTHEASTERN NORTH DAKOTA AND NORTHWESTERN MINNESOTA... SOUTHERLY WINDS WILL CONTINUE TO GUST FROM 35 TO 50 MPH OVER GRAND FORKS...POLK...RED LAKE...PENNINGTON...STEELE...TRAILL...NORMAN AND MAHNOMEN COUNTIES UNTIL 130 AM CDT. ATMOSPHERIC CONDITIONS HAVE PRODUCED A LOCALIZED STRONG PRESSURE GRADIENT THAT IS CONTRIBUTING TO THE DEVELOPMENT OF THESE STRONG SOUTHERLY WINDS. THIS PRESSURE GRADIENT IS EXPECTED TO WEAKEN AFTER 1 AM CDT AND THE WINDS SHOULD BEGIN TO WEAKEN. NG
Special weather statement, Aug 31, 10:46 PM CDT, 32 minutes before
MNZ001-002-013>015-022-NDZ027-029-030-010645- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1045 PM CDT SUN AUG 31 1997 ...GUSTY WINDS EXPECTED TO CONTINUE OVER PARTS OF NORTHEASTERN NORTH DAKOTA AND NORTHWESTERN MINNESOTA. SOUTHERLY WINDS WILL CONTINUE TO GUST FROM 35 TO 50 MPH OVER GRAND FORKS...POLK...RED LAKE...PENNINGTON...STEELE...TRAILL...NORMAN AND MAHNOMEN COUNTIES UNTIL 130 AM CDT. ATMOSPHERIC CONDITIONSd HAVE PRODUCED A LOCALIZED STRONG PRESSURE GRADIENT THAT IS CONTRIBUTING TO THE DEVELOPMENT OF THESE STRONG SOUTHERLY WINDS. THIS PRESSURE GRADIENT IS EXPECTED TO WEAKEN AFTER 1 AM CDT AND THE WINDS SHOULD BEGIN TO WEAKEN. NG
Special weather statement, Aug 31, 10:47 PM CDT, 31 minutes before
MNZ001-002-013>015-022-NDZ027-029-030-010645- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1045 PM CDT SUN AUG 31 1997 ...GUSTY WINDS EXPECTED TO CONTINUE OVER PARTS OF NORTHEASTERN NORTH DAKOTA AND NORTHWESTERN MINNESOTA... SOUTHERLY WINDS WILL CONTINUE TO GUST FROM 35 TO 50 MPH OVER GRAND FORKS...POLK...RED LAKE...PENNINGTON...STEELE...TRAILL...NORMAN AND MAHNOMEN COUNTIES UNTIL 130 AM CDT. ATMOSPHERIC CONDITIOfNS HAVE PRODUCED A LOCALIZED STRONG PRESSURE GRADIENT THAT IS CONTRIBUTING TO THE DEVELOPMENT OF THESE STRONG SOUTHERLY WINDS. THIS PRESSURE GRADIENT IS EXPECTED TO WEAKEN AFTER 1 AM CDT AND THE WINDS SHOULD BEGIN TO WEAKEN. NG
The office that day
Everything else NWS Grand Forks, ND issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 31, 8:37 PM CDT | Severe Thunderstorm Warning | FGF | Barnes | 38 min |
| Aug 31, 9:17 PM CDT | Severe Thunderstorm Warning | FGF | Eddy | 28 min |
| Aug 31, 10:00 PM CDT | Tornado Warning | FGF | Barnes | 30 min |
| Aug 31, 10:29 PM CDT | Severe Thunderstorm Warning | FGF | Barnes | 31 min |
| Sep 1, 1:22 AM CDT | Flash Flood Warning | FGF | Barnes, Griggs | 3 hr |
| Sep 1, 1:27 AM CDT | Severe Thunderstorm Warning | FGF | Barnes | 48 min |
| Sep 1, 2:13 AM CDT | Severe Thunderstorm Warning | FGF | Cass | 47 min |
| Sep 1, 2:15 AM CDT | Severe Thunderstorm Warning | FGF | Barnes | 30 min |
| Sep 1, 2:30 AM CDT | Flash Flood Warning | FGF | Cass | 4 hr |
Nearby
Severe Thunderstorm Warnings in North Dakota, 1997Every severe thunderstorm warning in 1997
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.