Alert archive / North Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 144, NWS Grand Forks, ND

July 29, 2002Pembina County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 29, 2002, 11:28 PM CDT for Pembina County, North Dakota. It was in force for 47 min. 2 reports 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 29, 2002, 11:28 PM CDT (04:28 UTC)
Expired
Jul 30, 2002, 12:15 AM CDT
In force
47 min
Issued by
NWS Grand Forks, ND
Area
Counties, with a storm outline in the text

County Pembina County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 150 km from the middle of the area, began a volume at 04:27 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 29, 11:35 PM CDTHail 0.75Cavalier, ND
Jul 30, 12:00 AM CDTThunderstorm WindHamilton, NDTwo trees 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

International Fa, MN (KINL), launched 00:00Z, 4.5 hours before the alert went out and 318 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, International Fa, MN at 00:00Z on 2002-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 205 joules per kilogram.LCLEL10008507005003002001001 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, International Fa, MN at 00:00Z on 2002-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.1939587897Sfc1 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
205 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
1684 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
102 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

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

729 
WUUS53 KFGF 300428
SVRFAR
NDC067-300515-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
1127 PM CDT MON JUL 29 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  NORTHERN PEMBINA COUNTY IN NORTHEAST NORTH DAKOTA.

* UNTIL 1215 AM CDT.

* AT 1115 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 8 MILES WEST OF LEROY...OR ABOUT 23 MILES
  NORTHEAST OF LANGDON...MOVEMENT WAS TO THE EAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  BACKOO AT 1130 PM...
  CAVALIER AT 1140 PM...
  BATHGATE AT 1145 PM AND
  HAMILTON AT 1150 PM.

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

LAT...LON 4900 9786 4883 9794 4863 9720 4886 9718

23

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 29, 8:55 PM CDT, 2 hours 33 minutes earlier.

Area forecast discussion, Jul 29, 8:55 PM CDT, 2 hours 33 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
855 PM CDT MON JUL 29 2002

FORECAST CHALLENGE FOR TONIGHT IS PRECIPITATION. CURRENT SATELLITE
IMAGERY SHOWS SOME MID LEVEL CLOUD COVER PRIMARILY OVER ND PARTS OF
AREA. KMVX HAS ISOLATED SHOWERS CONTINUING TO DEVELOP IN SE ND AND
OTHERS SHOWERS MOVING TOWARDS DVL AREA. WHEN LOOKING AT MODEL
INITIALIZATION CONDITIONS AS COMPARED TO MSAS DATA...AVN AND ETA
BOTH CLOSE. LATEST MSAS SURFACE ANALYSIS HAS SFC LOW IN CENTRAL SD
WITH HIGH PRESSURE RIDGE EXTENDING FROM SE SASK INTO NE ND. MSAS
SHOWS BEST INSTABILITY REMAINING IN SE ND WITH LIFTED INDICES TO -6.
HOWEVER...BEST SURFACE MOISTURE FLUX CONVERGENCE HAS BEEN MOVING OUT
OF THIS AREA INTO NE SD. ALREADY UPDATED FORECAST FOR ISOLATED
SHOWERS IN SE ND. WITH INSTABILITY AXIS EXPECTED TO CONTINUE TO MOVE
SE THROUGH THE EVENING...CURRENT FORECAST STILL IN PRETTY GOOD
SHAPE. CONSEQUENTLY...NO ADDITIONAL UPDATE PLANNED AT THIS TIME.

.FGF...NONE.

NG

Nearby

Severe Thunderstorm Warnings in North Dakota, 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.