Alert archive / Minnesota / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 150, NWS Grand Forks, ND
NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 31, 2002, 6:18 AM CDT for Otter Tail County, Minnesota. It was in force for 42 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 31, 2002, 6:18 AM CDT (11:18 UTC)
- Expired
- Jul 31, 2002, 7:00 AM CDT
- In force
- 42 min
- Issued by
- NWS Grand Forks, ND
- Area
- Counties, with a storm outline in the text
County Otter Tail County, MN
The radar
The Fargo/Grand Forks radar (KMVX), 188 km from the middle of the area, began a volume at 11:21 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 31, 6:20 AM CDT | Thunderstorm Wind | Ottertail, MN | Branches were blown down. |
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
Minneapolis, MN (KMPX), launched 00:00Z, 11.3 hours before the alert went out and 226 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
- 3426 J/kg
- Mixed-layer CIN
- -40 J/kg
- Mixed-layer LCL
- 1178 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 80 m²/s²
- 0-3 km storm-relative helicity
- 215 m²/s²
- Significant tornado parameter
- 3.4
- Supercell composite
- 19.1
The text
As transmitted, in the capitals the NWS used until 2016.
680 WUUS53 KFGF 311118 SVRFAR MNC111-311200- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS 617 AM CDT WED JUL 31 2002 THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... EASTERN OTTER TAIL COUNTY IN WEST CENTRAL MINNESOTA. * UNTIL 700 AM CDT. * AT 615 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 5 MILES SOUTH OF OTTERTAIL...OR ABOUT 25 MILES EAST OF FERGUS FALLS...MOVEMENT WAS TO THE EAST AT 65 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... HENNING AT 620 AM... DEER CREEK AT 625 AM AND BLUFFTON AT 630 AM. REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 AM WEDNESDAY MORNING FOR WEST CENTRAL MINNESOTA. LAT...LON 4645 9569 4627 9563 4618 9518 4663 9520 04 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 31, 3:15 AM CDT, 3 hours 3 minutes earlier.
Area forecast discussion, Jul 31, 3:15 AM CDT, 3 hours 3 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 315 AM CDT WED JUL 31 2002 FORECAST CHALLENGE CONCERNS EARLY TSRA THREAT AND TEMPERATURES. MODELS IN FAIR AGREEMENT THROUGH PERIOD ALTHOUGH PREFERRED SFC FEATURES FROM ETA EARLY. MAIN CONCERN TODAY WILL THREAT FOR MAINLY AFTERNOON AND EVENING SEVERE TSRA. SFC LOW PRESSURE STILL FAIRLY UNORGANIZED EARLY THIS MORNING HOWEVER FEATURE GAINS BETTER DEFINITION AND SHIFTS EAST TO WESTERN FA BY MID AFTERNOON AND ACROSS FORECAST AREA DURING LATE AFTERNOON EARLY EVENING HOURS. IN THE NEAR TERM SEVERAL CLUSTERS OF TSRA FROM KMVX/KBIS 88S WILL PROPAGATE EAST THROUGH FA EARLY THIS AM BEFORE GRADUALLY DIMINISHING. WILL LIKELY SEE A BREAK FROM LATE AM INTO MID AFTERNOON. CONVECTIVE DEBRIS CLOUDS WILL HAVE SOME IMPACT ON TEMPS HOWEVER DO EXPECT A GOOD DOSE OF AFTERNOON SOLAR TO AID IN DESTABILIZATION. AS SFC LOW BECOMES BETTER DEFINED INCREASING SOUTHERLY FLOW WILL PROVIDE GOOD LOW LEVEL MOISTURE FLUX INTO AREA. AT THIS TIME FAVORED AREA FOR INITIATION OF AFTERNOON CONVECTION LOOKS TO BE ACROSS THE NORTH WITH LESS CAPPING AND ON NOSE OF UPPER JET. AS SIGNIFICANT SHORTWAVE APPROACHES REGION GOOD MID LEVEL COOLING WILL PUT WHOLE AREA UNDER GUN AS CAP ERODES WITH EXCEPTION OF FAR NW BEHIND FRONT. SVR THREAT WILL SHIFT EAST OF RIVER THIS EVENING AND BASED ON FROPA SHOULD EXIT FA BY MIDNIGHT. STRONG COLD ADVECTION DIVES FROM NW TO SE ACROSS FA OVERNIGHT. WE SHOULD THEN SEE MUCH COOLER TEMPERATURES BUT RAIN FREE CONDITIONS AS SFC AND MID LEVEL RIDGING TAKES CONTROL. RETURN FLOW SETS UP AHEAD OF NEXT WAVE LATE FRIDAY WITH OUR NEXT CHANCE OF PCPN STILL ON TRACK FOR FRIDAY NIGHT/SAT. NO CHANGES PLANNED TO EXTENDED. .FGF...NONE. VOELKER
The office that day
Everything else NWS Grand Forks, ND issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 31, 5:26 AM CDT | Severe Thunderstorm Warning | FGF | Grant, Otter Tail, Wilkin | 49 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.