Alert archive / Minnesota / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 166, NWS Grand Forks, ND

July 18, 1998Grant County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 18, 1998, 11:31 AM CDT for Grant County, Minnesota. It was in force for 34 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
Jul 18, 1998, 11:31 AM CDT (16:31 UTC)
Expired
Jul 18, 1998, 12:05 PM CDT
In force
34 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

County Grant County, MN

The radar

The Aberdeen radar (KABR), 194 km from the middle of the area, began a volume at 16:35 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

TimeReportWhereRemark
Jul 18, 11:49 AM CDTHail 0.75Herman, MN

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 12:00Z, 4.5 hours before the alert went out and 219 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-pSkew-T log-p diagram, Aberdeen, SD at 12:00Z on 1998-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1629 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Aberdeen, SD at 12:00Z on 1998-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 116 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1629 J/kg
Mixed-layer CIN
-175 J/kg
Mixed-layer LCL
970 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
116 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

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

304 
WUUS1 KFAR 181633 RRA
SVRFAR
MNC051-181705-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1131 AM CDT SAT JUL 18 1998

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  GRANT COUNTY IN WEST CENTRAL MINNESOTA

* UNTIL 1205 PM CDT

* AT 1130 AM CDT...DOPPLER WEATHER RADAR INDICATED A SEVERE THUNDER-
  STORM 10 MILES NORTHWEST OF HERMAN...OR ABOUT 30 MILES SOUTHWEST OF
  FERGUS FALLS...MOVING SOUTHEAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  NORCROSS AT 1140 AM CDT
  HERMAN AT 1145 AM CDT

IF SEVERE WEATHER IS OBSERVED CONTACT YOUR LOCAL LAW ENFORCEMENT
AND ASK THEM TO RELAY YOUR INFORMATION TO THE NATIONAL WEATHER
SERVICE.

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 Jul 18, 10:30 AM CDT, 1 hour 1 minute earlier.

Area forecast discussion, Jul 18, 10:30 AM CDT, 1 hour 1 minute before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1030 AM CDT SAT JUL 18 1998

FIRST PERIOD DISCUSSION...N-S BKN LINE OF TSRA ESSENTIALLY ALNG
RED RVR. MOVG SE ARND 30KT. STRM WERE ALNG A WM FNT ACRS ERN ND.
ADAP SHOWING PRES FALLS ERN ND/NW MN ALNG WM FNT. LIS WERE
LOWEST ACRS THE CNTRL DAKS. STLT SHOWG PLENTY OF CLR SKIES TO
THE W AND SHOULD HEAT UP GOOD TDY. MIXG RATIOS STILL HIEST
TO THE W. JET MAX/SHORT WV TO MOV INTO SRN MAN THIS AFTN
MAY KEEP WX INTERESTING THIS AFTN. WL CHECK OVR ZONES.

HOPPES

In the hours before

Special weather statement, Jul 18, 6:50 AM CDT, 4 hours 41 minutes before
MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052-053-181200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
650 AM CDT SAT JUL 18 1998

...SLIGHT RISK OF SEVERE WEATHER TODAY ACROSS EASTERN NORTH DAKOTA AND
NORTHWEST MINNESOTA...

A DEVELOPING LOW PRESSURE AREA AND ASSOCIATED WARM FRONT WILL PUSH
ACROSS EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA THIS MORNING...TO
BE FOLLOWED BY A COLD FRONT THIS AFTERNOON. WARMER AND MORE UNSTABLE
AIR WILL MOVE INTO THE REGION WITH THE WARM-FRONT...SETTING OFF
SCATTERED THUNDERSTORMS THIS MORNING MAINLY ACROSS EASTERN NORTH DAKOTA
AND NORTHWEST MINNESOTA. SOME OF THESE STORMS MAY CONTAIN LARGE HAIL.

BY THIS AFTERNOON...THE COLD FRONT WILL ENCOUNTER THE MOIST AND
UNSTABLE ATMOSPHERE AND TRIGGER MORE THUNDERSTORMS. THE STORMS THAT
DEVELOP THIS AFTERNOON WILL HAVE THE POTENTIAL TO QUICKLY BECOME
SEVERE. THE PREFERRED TIME FOR THE SEVERE WEATHER IS EXPECTED TO BE
MAINLY AFTER 2 PM FROM DEVILS LAKE TO GRAND FORKS...AFTER 3 PM IN THE
FARGO AREA...AND AFTER 5 PM WEST-CENTRAL AND THE LAKES COUNTRY OF
MINNESOTA. LARGE HAIL...DAMAGING WINDS AND AN ISOLATED TORNADO ARE ALL
POSSIBLE LATER THIS AFTERNOON AND TONIGHT.

IN ADDITION...BY THIS EVENING THE MAIN THREAT MAY ONCE AGAIN TURN
TOWARDS VERY HEAVY RAINS ACROSS THE LAKES COUNTRY AS THE STORMS SLIDE
SOUTHEAST TOWARD CENTRAL AND EVENTUALLY SOUTHERN MINNESOTA TONIGHT.
THEREFORE...A FLASH FLOOD WATCH HAS BEEN POSTED FOR THIS AREA FOR
TONIGHT.

PLEASE STAY TUNED TO NOAA WEATHER RADIO OR YOUR FAVORITE SOURCE OF
WEATHER INFORMATION ON THE POTENTIAL FOR SEVERE WEATHER LATER TODAY.
THIS HAZARDOUS WEATHER OUTLOOK WILL BE UPDATED THIS AFTERNOON IF
CONDITIONS WARRANT.

SOROKA
Special weather statement, Jul 18, 6:50 AM CDT, 4 hours 41 minutes before
MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052-053-181200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
650 AM CDT SAT JUL 18 1998

...SLIGHT RISK OF SEVERE WEATHER TODAY ACROSS EASTERN NORTH DAKOTA AND
NORTHWEST MINNESOTA...

A DEVELOPING LOW PRESSURE AREA AND ASSOCIATED WARM FRONT WILL PUSH
ACROSS EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA THIS MORNING...TO
BE FOLLOWED BY A COLD FRONT THIS AFTERNOON. WARMER AND MORE UNSTABLE
AIR WILL MOVE INTO THE REGION WITH THE WARM-FRONT...SETTING OFF
SCATTERED THUNDERSTORMS THIS MORNING MAINLY ACROSS EASTERN NORTH DAKOTA
AND NORTHWEST MINNESOTA. SOME OF THESE STORMS MAY CONTAIN LARGE HAIL.

BY THIS AFTERNOON...THE COLD FRONT WILL ENCOUNTER THE MOIST AND
UNSTABLE ATMOSPHERE AND TRIGGER MORE THUNDERSTORMS. THE STORMS THAT
DEVELOP THIS AFTERNOON WILL HAVE THE POTENTIAL TO QUICKLY BECOME
SEVERE. THE PREFERRED TIME FOR THE SEVERE WEATHER IS EXPECTED TO BE
MAINLY AFTER 2 PM FROM DEVILS LAKE TO GRAND FORKS...AFTER 3 PM IN THE
FARGO AREA...AND AFTER 5 PM WEST-CENTRAL AND THE LAKES COUNTRY OF
MINNESOTA. LARGE HAIL...DAMAGING WINDS AND AN ISOLATED TORNADO ARE ALL
POSSIBLE LATER THIS AFTERNOON AND TONIGHT.

IN ADDITION...BY THIS EVENING THE MAIN THREAT MAY ONCE AGAIN TURN
TOWARDS VERY HEAVY RAINS ACROSS THE LAKES COUNTRY AS THE STORMS SLIDE
SOUTHEAST TOWARD CENTRAL AND EVENTUALLY SOUTHERN MINNESOTA TONIGHT.
THEREFORE...A FLASH FLOOD WATCH HAS BEEN POSTED FOR THIS AREA FOR
TONIGHT.

PLEASE STAY TUNED TO NOAA WEATHER RADIO OR YOUR FAVORITE SOURCE OF
WEATHER INFORMATION ON THE POTENTIAL FOR SEVERE WEATHER LATER TODAY.
THIS HAZARDOUS WEATHER OUTLOOK WILL BE UPDATED THIS AFTERNOON IF
CONDITIONS WARRANT.

SOROKA
Special weather statement, Jul 18, 11:27 AM CDT, 4 minutes before
MNZ001>004-007-008-013>015-022-027>031-NDZ006>008-014>016-024-
026>030-038-039-049-052-053-181830-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1127 AM CDT SAT JUL 18 1998

...SEVERE THUNDERSTORM WATCH HAS BEEN CANCELLED FOR PARTS OF EASTERN
NORTH DAKOTA AND NORTHWEST MINNESOTA...

THE FOLLOWING COUNTIES IN EASTERN NORTH DAKOTA HAVE BEEN DROPPED FROM
THE SEVERE THUNDERSTORM WATCH #748:

TOWNER...CAVALIER...RAMSEY...BENSON...EDDY...PEMBINA...WALSH...
NELSON...GRAND FORKS...GRIGGS...STEELE...AND TRAILL

AND IN NORTHWEST MINNESOTA THE FOLLOWING COUNTIES HAVE ALSO BEEN
CANCELLED:

KITTSON...MARSHALL...AND WEST POLK.

HOWEVER THE SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1PM CDT
FOR THE FOLLOWING COUNTIES IN EASTERN NORTH DAKOTA:

BARNES...CASS...RANSOM...SARGENT...RICHLAND.

AND THE FOLLOWING COUNTIES IN NORTHWEST MINNESOTA ALSO REMAIN IN
EFFECT:

PENNINGTON...RED LAKE...EAST POLK...NORMAN...MAHNOMEN...
BECKER...CLAY...OTTER TAIL AND WILKIN.

A WATCH MEANS SEVERE THUNDERSTORMS ARE POSSIBLE IN AND NEAR THE WATCH
AREA. STAY TUNED TO YOUR LOCAL MEDIA...CABLE TELEVISION OR NOAA WEATHER
RADIO FOR LATER STATEMENTS AND WARNINGS.

HOPPE\S
Special weather statement, Jul 18, 11:27 AM CDT, 4 minutes before
MNZ001>004-007-008-013>015-022-027>031-NDZ006>008-014>016-024-
026>030-038-039-049-052-053-181830-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1127 AM CDT SAT JUL 18 1998

...SEVERE THUNDERSTORM WATCH HAS BEEN CANCELLED FOR PARTS OF EASTERN
NORTH DAKOTA AND NORTHWEST MINNESOTA...

THE FOLLOWING COUNTIES IN EASTERN NORTH DAKOTA HAVE BEEN DROPPED FROM
THE SEVERE THUNDERSTORM WATCH #748:

TOWNER...CAVALIER...RAMSEY...BENSON...EDDY...PEMBINA...WALSH...
NELSON...GRAND FORKS...GRIGGS...STEELE...AND TRAILL

AND IN NORTHWEST MINNESOTA THE FOLLOWING COUNTIES HAVE ALSO BEEN
CANCELLED:

KITTSON...MARSHALL...AND WEST POLK.

HOWEVER THE SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1PM CDT
FOR THE FOLLOWING COUNTIES IN EASTERN NORTH DAKOTA:

BARNES...CASS...RANSOM...SARGENT...RICHLAND.

AND THE FOLLOWING COUNTIES IN NORTHWEST MINNESOTA ALSO REMAIN IN
EFFECT:

PENNINGTON...RED LAKE...EAST POLK...NORMAN...MAHNOMEN...
BECKER...CLAY...OTTER TAIL AND WILKIN.

A WATCH MEANS SEVERE THUNDERSTORMS ARE POSSIBLE IN AND NEAR THE WATCH
AREA. STAY TUNED TO YOUR LOCAL MEDIA...CABLE TELEVISION OR NOAA WEATHER
RADIO FOR LATER STATEMENTS AND WARNINGS.

HOPPE\S

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 11:07 AM CDTSevere Thunderstorm WarningFGFWilkin33 min
Jul 18, 11:44 AM CDTSevere Thunderstorm WarningFGFKittson31 min
Jul 18, 12:15 PM CDTSevere Thunderstorm WarningFGFKittson, Roseau50 min
Jul 18, 3:16 PM CDTSevere Thunderstorm WarningFGFBeltrami44 min
Jul 18, 5:14 PM CDTTornado WarningFGFPennington31 min
Jul 18, 5:41 PM CDTTornado WarningFGFPennington34 min
Jul 18, 6:01 PM CDTSevere Thunderstorm WarningFGFRed Lake49 min
Jul 18, 6:33 PM CDTSevere Thunderstorm WarningFGFPolk32 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1998Every severe thunderstorm warning in 1998

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.