Alert archive / Minnesota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 343, NWS Grand Forks, ND

September 2, 2002Otter Tail County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Sep 2, 2002, 7:51 AM CDT for Otter Tail County, Minnesota. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 2, 2002, 7:51 AM CDT (12:51 UTC)
Expired
Sep 2, 2002, 8:30 AM CDT
In force
39 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), 183 km from the middle of the area, began a volume at 12:51 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.

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 12:00Z, 0.9 hours before the alert went out and 231 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, Minneapolis, MN at 12:00Z on 2002-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2159 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, Minneapolis, MN at 12:00Z on 2002-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 168 square meters per square second.193958Sfc1 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
2159 J/kg
Mixed-layer CIN
-235 J/kg
Mixed-layer LCL
827 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
168 m²/s²
0-3 km storm-relative helicity
203 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.4

Open this sounding in Storm Lab

The text

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

770 
WUUS53 KFGF 021251
SVRFAR
MNC111-021330-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
751 AM CDT MON SEP 2 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  OTTER TAIL COUNTY IN WEST CENTRAL MINNESOTA.

* UNTIL 830 AM CDT.

* AT 746 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 4 MILES SOUTH OF AMOR...OR ABOUT 17 MILES EAST
  OF FERGUS FALLS...MOVEMENT WAS TO THE EAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  OTTERTAIL AT 755 AM...
  HENNING AT 805 AM AND
  DEER CREEK AT 810 AM.

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

LAT...LON 4644 9581 4626 9577 4630 9526 4650 9530

7

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 Sep 2, 1:50 AM CDT, 6 hours 1 minute earlier.

Area forecast discussion, Sep 2, 1:50 AM CDT, 6 hours 1 minute before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
150 AM CDT MON SEP 2 2002

...MAIN FORECAST CHALLENGE THIS PACKAGE CENTERS ON LINGERING POP
THREAT THIS MORNING AND WIND POTENTIAL WITH STRENGTHENING NORTHWEST
PRESSURE GRADIENT IN WAKE OF FRONT REMAINDER OF DAY...

.CURRENT OBSERVATIONAL OVERVIEW...
06Z MSAS ANALYSIS DEPICTED LOW PRESSURE OVER EXTREME WESTERN
MANITOBA PROVINCE WITH ASSOCIATED PRE-FRONTAL TROUGH AXIS ACROSS
CENTRAL NORTH DAKOTA. FURTHER UPSTREAM PARENT COLD FRONT WAS
SITUATED FROM EXTREME SOUTHEAST SASK PROVINCE TO WESTERN NORTH
DAKOTA. LATEST PRESSURE TENDENCY FIELDS SUGGESTS GOOD RISE/FALL
COUPLE ASSOCIATED WITH FEATURE. LATEST RADAR MOSAIC INDICATED SOME
CONVECTIVE TYPE MAINLY HIGH BASED SHOWER ACTIVITY (LITTLE IF ANY
LIGHTNING STRIKES) IN VICINITY OF ENHANCED MOISTURE FLUX CONVERGENCE
AHEAD OF COLD FRONT.

.FORECAST DETAILS...
FINALLY LIGHT AT THE END OF THE TUNNEL WITH RESPECT TO CONVECTIVE
THREAT ACROSS THE REGION. EXPECT STRONG UPSTREAM SHORTWAVE TROUGH TO
FINALLY KICK PARENT COLD FRONT THROUGH AREA THIS MORNING. REVIEW OF
FORECASTED SOUNDINGS SUGGESTS THE POTENTIAL FOR ELEVATED CONVECTION
WITH FROPA...PER INVERTED V SOUNDING (STEEP LAPSE RATES 850-700MB
LAYER) FOR AREAS FROM THE RED RIVER VALLEY EAST EARLY TODAY. IN
WAKE OF FRONT GOOD NORTHWESTERLY PUNCH OF DRIER AIR ADVECTS INTO THE
REGION. TIGHTENING NORTHWESTERLY PRESSURE GRADIENT COUPLED WITH
UNIDIRECTIONAL FLOW WITH HEIGHT AND ADIABATIC MIXING LAYER TO ALMOST
700MB SHOULD RESULT IN WINDY CONDITIONS. BASED ON LATEST GUIDANCE
FEEL WINDS WILL STAY JUST BELOW WIND ADVISORY CRITERIA. EXPECT WINDS
TO ABATE AND DECOUPLE TONIGHT AS HIGH PRESSURE OVER THE CENTRAL
PLAINS RIDGES INTO THE DAKOTAS. FRIENDLY CONFINES OF HIGH SHOULD
SLOWLY ERODE AND SLIP AWAY LATE TUESDAY INTO TUESDAY NIGHT AS
SOUTHERLY FLOW BECOMES ESTABLISHED ONCE AGAIN ACROSS THE NORTHERN
PLAINS AHEAD DEEPENING NORTHWEST CONUS UPPER LEVEL TROUGH. NO
CHANGES PLANNED TO EXTENDED PACKAGE PENDING NO REAL SURPRISES WITH
NEW MRF.

.FGF...NONE.

BERG

In the hours before

Special weather statement, Sep 2, 6:45 AM CDT, 1 hour 6 minutes before
MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-021400-

SPECIAL WEATHER STATEMENT
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
645 AM CDT MON SEP 2 2002

...NO SEVERE THUNDERSTORMS ARE EXPECTED ACROSS EASTERN NORTH DAKOTA
AND NORTHWEST AND WEST CENTRAL MINNESOTA TODAY OR TONIGHT...

SYNOPSIS...A COLD FRONT WILL CONTINUE TO SWEEP EAST OF THE REGION
TODAY. IN THE WAKE OF THE FRONT HIGH PRESSURE FROM THE CENTRAL
PLAINS WILL RIDGE INTO THE REGION. SCATTERED THUNDERSTORMS ARE
POSSIBLE EAST OF THE RED RIVER VALLEY THIS MORNING IN CONJUNCTION
WITH THE PASSAGE OF THE FRONT...HOWEVER NONE OF THE STORMS ARE
EXPECTED TO BECOME SEVERE.

BERG

NNNN

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 2, 5:55 AM CDTSevere Thunderstorm WarningFGFClay50 min
Sep 2, 8:19 AM CDTSevere Thunderstorm WarningFGFWadena41 min
Sep 2, 8:34 AM CDTTornado WarningFGFWadena41 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.