Alert archive / Minnesota / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 127, NWS Grand Forks, ND
NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 20, 2002, 7:43 AM CDT for Mahnomen County, Norman County, Minnesota. It was in force for 47 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
- Jul 20, 2002, 7:43 AM CDT (12:43 UTC)
- Expired
- Jul 20, 2002, 8:30 AM CDT
- In force
- 47 min
- Issued by
- NWS Grand Forks, ND
- Area
- Counties, with a storm outline in the text
Counties Mahnomen County, MN, Norman County, MN
The radar
The Fargo/Grand Forks radar (KMVX), 94 km from the middle of the area, began a volume at 12:47 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 |
|---|---|---|---|
| Jul 20, 8:15 AM CDT | Hail 0.75 | Mahnomen, 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.
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
International Fa, MN (KINL), launched 12:00Z, 0.7 hours before the alert went out and 253 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1018 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 93 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
363 WUUS53 KFGF 201243 SVRFAR MNC087-107-201330- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS 743 AM CDT SAT JUL 20 2002 THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... MAHNOMEN COUNTY IN NORTHWEST MINNESOTA AND NORMAN COUNTY IN NORTHWEST MINNESOTA. * UNTIL 830 AM CDT. * AT 742 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 3 MILES SOUTH OF TWIN VALLEY...OR ABOUT 34 MILES NORTHWEST OF DETROIT LAKES...MOVEMENT WAS TO THE EAST AT 25 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... FAITH AT 750 AM AND MAHNOMEN AT 800 AM. REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. LAT...LON 4735 9638 4717 9620 4721 9575 4741 9588 8 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 Jul 20, 2:15 AM CDT, 5 hours 28 minutes earlier.
Area forecast discussion, Jul 20, 2:15 AM CDT, 5 hours 28 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 215 AM CDT SAT JUL 20 2002 FORECAST CHALLENGE IS CONVECTION TODAY INTO TONIGHT...THEN TEMPS .OVERVIEW... SFC TROUGH NOW ENTERING WESTERN ND...ALONG WITH ONE AREA OF LOW PRESSURE NEAR PIR...AND ANOTHER IN SOUTHERN SASKATCHEWAN. ALL OF EASTERN ND UNSTABLE WITH DEWPOINTS NEAR 70...WITH MID 60S TO THE EAST IN MN. ETA DID THE BEST JOB INITIALIZING CONVECTION IN WESTERN ND AND BOUNDARY LAYER MOISTURE...SO WILL USE THIS FORECAST PACKAGE. .TODAY... EXPECT ELEVATED ROUND OF CONVECTION TO BE ONGOING ACROSS EASTERN ND...INTO WEST CENTRAL MN THIS MORNING ON HEELS OF 45KT 500MB SPEED MAX AND 30KT LOW LEVEL JET. BY AFTERNOON...CAPES APPROACH 3000J/KG...ALONG WITH PRECIPITABLE WATERS NEAR 2 INCHES AND GOOD FORCING ALONG SFC TROUGH. CAP SHOULD WEAKEN AROUND 18Z FOR POTENTIAL SEVERE WEATHER OUTBREAK IN EASTERN ND...THEN MOVING INTO MN BY EVENING. WITH 50KT NEAR 500MB...GOOD SHEAR AND RIGHT ENTRANCE REGION OF 75KT 300MB JET...EXPECT A FEW SUPERCELLS WITH ISOLATED TORNADOES...WHICH MAY CONSOLIDATE INTO MCS AS IT MOVES EAST THIS EVENING. ANY STORMS WILL DROP HEAVY RAIN...SO WILL MENTION IN ZONES WITH SEVERE WORDING AND LIKELY POPS. REFER TO SWODY1 FOR FURTHER DETAILS ON SEVERE WEATHER THREAT. .TONIGHT THROUGH MONDAY... DRIER AIR WILL FILTER THROUGH REGION BY 12Z SUNDAY...IN WAKE OF SHORTWAVE AND SUBSIDENCE BEHIND VORTICITY MAXIMUM. 850MB TEMPS COOL TO AROUND +15C ON SUNDAY...SO EXPECT TEMPS WITHIN A FEW DEGREES OF 80 ALONG WITH PLENTY OF SUN. BY MONDAY...A SECONDARY COLD FRONT WILL PUSH INTO NORTHERN ZONES...SO WILL INSERT SCATTERED THUNDER MENTION IN NORTHEAST AS TEMPS COOL INTO THE 70S. .FGF...FLOOD WARNING CONTINUES FOR RED RIVER NEAR OSLO. KELLENBENZ
In the hours before
Special weather statement, Jul 20, 5:00 AM CDT, 2 hours 43 minutes before
MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024- 026>030-038-039-049-052>054-201400- SPECIAL WEATHER STATEMENT HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS 500 AM CDT SAT JUL 20 2002 ...THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS TODAY ACROSS EASTERN NORTH DAKOTA...NORTHWEST AND WEST CENTRAL MINNESOTA... SYNOPSIS...ABUNDANT LOW LEVEL MOISTURE WILL COMBINE WITH AN UPPER LEVEL DISTURBANCE AND PRODUCE THUNDERSTORMS TODAY ACROSS THE ENTIRE REGION. THUNDERSTORMS WILL MOVE ACROSS EASTERN NORTH DAKOTA THIS MORNING...AND INTO WEST CENTRAL MINNESOTA BY LATE MORNING. ADDITIONAL THUNDERSTORMS WILL DEVELOP EARLY THIS AFTERNOON ACROSS EASTERN NORTH DAKOTA...AND MOVE INTO ADJACENT NORTHWEST AND WEST CENTRAL MINNESOTA BY LATE AFTERNOON INTO THIS EVENING. AREA OF CONCERN...THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS ACROSS ALL OF EASTERN NORTH DAKOTA...NORTHWEST AND WEST CENTRAL MINNESOTA TODAY. TIME...7AM UNTIL 9 PM. TYPE OF HAZARD...LARGE HAIL AND DAMAGING WIND ARE THE MAIN THREAT ...ALONG WITH ISOLATED TORNADOES POSSIBLE THIS AFTERNOON. ANY THUNDERSTORM WILL ALSO PRODUCE HEAVY RAIN...WITH SOME LOCALIZED FLOODING POSSIBLE. KELLENBENZ NNNN
The office that day
Everything else NWS Grand Forks, ND issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 4:42 AM CDT | Severe Thunderstorm Warning | FGF | Grant | 48 min |
Nearby
Severe Thunderstorm Warnings in Minnesota, 2002Every 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.