Alert archive / North Dakota / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 183, NWS Grand Forks, ND

July 20, 1998Ransom County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 20, 1998, 3:06 PM CDT for Ransom County, North Dakota. It was in force for 34 min. 2 reports 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 20, 1998, 3:06 PM CDT (20:06 UTC)
Expired
Jul 20, 1998, 3:40 PM CDT
In force
34 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

County Ransom County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 122 km from the middle of the area, began a volume at 20:09 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 20, 3:40 PM CDTHail 2.25Sheldon, ND
Jul 20, 3:48 PM CDTHail 1Mc Leod, 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 12:00Z, 8.1 hours before the alert went out and 182 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 1998-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2746 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 1998-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
2746 J/kg
Mixed-layer CIN
-92 J/kg
Mixed-layer LCL
934 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

011 
WUUS1 KFAR 202007 RRA
SVRFAR
NDC073-202040-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
306 PM CDT MON JUL 20 1998

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN RANSOM COUNTY IN SOUTHEASTERN NORTH DAKOTA

* UNTIL 340 PM CDT

* AT 306 PM...RADAR INDICATED A SEVERE THUNDERSTORM WARNING 7
  NORTHEAST OF LISBON OR 40 MILES SOUTHWEST OF FARGO.  THE STORM WAS
  MOVING SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ANSELM

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

SCHUMACHER

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 20, 3:00 PM CDT, 6 minutes earlier.

Area forecast discussion, Jul 20, 3:00 PM CDT, 6 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
300 PM CDT MON JUL 20 1998

FIRST PERIOD DISCUSSION...ADAP SHOWING GOOD MSTR FLUX CONVERENGCE
FM TVF TO SARGENT CNTY ND. LIS WERE ALSO QUITE LOW AND THE
CAP WAS WEAKEST IN THE SAME AREA. UPR LVL JET MOVG ALNG THE
INTERNATIONAL BDR WITH STRMS LIKELY TO FIRE IN RFQ AS WARM MOIST
AIR GETS LIFTED UNDER JET INDUCED SUBSIDENCE. STRMS FIRING UP ARND
TVF. STLT SHOWING A LINE OF ENHANCED CU FM TVF TO DICKEY CNTY ND.
WATER VAPOR LOOP ALSO HAS HIR MID LVL MSTR MOVG IN. SHOULD SEE STRMS
DEVELOP ALONG MOIST/DRY INTERFACE AND ALONG SFC FNT. WNDS HAVE
BECM NW W SFC CU LINE ON STLT. XPC STRMS TO DEVELOP ALNG FNTL BNDRY
AND ESPECIALLY WHERE FNTL BNDRY WOULD INTERSECT MOIST/DRY INTERFACE.
CLRG SHOULD FOLLOW STRMS ACTIVITY TNGT XCP ALNG INTERNATIONAL BDR
WHERE MORE CLDS ARE XPCD. AS FAR AS TEMPS MOS SEEMS A LITTLE WARM
WITH DWPNTS IN THE UPR 40S IN WRN ND HOWEVER UPR 50S DWPNTS
WERE IN SRN MAN. TEMPS SHOUD BE WARMER ALNG THE NRN BDR WITH
HIR DWPNTS AND CLDS BY MORN...COOLER IN THE S. THINK LOWS WL BE
IN THE MID 50S IN FAR, FFM, DTL, PKD...AND UPR 50S GFK, FSE,
BJI, DVL...ARND 60 IN HCO, ROX, BDE.

HOPPES

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 10:02 AM CDTSevere Thunderstorm WarningFGFPembina33 min
Jul 20, 3:37 PM CDTSevere Thunderstorm WarningFGFRansom, Richland33 min
Jul 20, 4:08 PM CDTSevere Thunderstorm WarningFGFRichland32 min
Jul 20, 4:37 PM CDTSevere Thunderstorm WarningFGFRichland33 min
Jul 20, 5:12 PM CDTSevere Thunderstorm WarningFGFRichland33 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 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.