Alert archive / North Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 16, NWS Grand Forks, ND

May 12, 2002Walsh County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at May 12, 2002, 5:29 PM CDT for Walsh County, North Dakota. It was in force for 31 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
May 12, 2002, 5:29 PM CDT (22:29 UTC)
Expired
May 12, 2002, 6:00 PM CDT
In force
31 min
Issued by
NWS Grand Forks, ND
Area
Counties, with a storm outline in the text

County Walsh County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 105 km from the middle of the area, began a volume at 22:31 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
May 12, 5:45 PM CDTHail 0.88Grafton, NDThe hail covered the grass.

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, 10.5 hours before the alert went out and 294 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 12:00Z on 2002-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, International Fa, MN at 12:00Z on 2002-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -20 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
599 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
-20 m²/s²
0-3 km storm-relative helicity
-23 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KFGF 122229
SVRFAR
NDC099-122300-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
527 PM CDT SUN MAY 12 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  NORTHEASTERN WALSH COUNTY IN NORTHEAST NORTH DAKOTA.

* UNTIL 600 PM CDT.

* AT 526 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 7 MILES WEST OF HERRICK...OR ABOUT 7 MILES
  NORTH OF GRAFTON...MOVEMENT WAS TO THE SOUTHEAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  OAKWOOD AT 535 PM.
  CROSSING I-29 AT 550 PM.

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

LAT...LON 4855 9730 4848 9755 4828 9714 4848 9716

77

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 May 12, 2:42 PM CDT, 2 hours 47 minutes earlier.

Area forecast discussion, May 12, 2:42 PM CDT, 2 hours 47 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
242 PM CDT SUN MAY 12 2002

...FORECAST CHALLENGE IS PRECIPITATION CHANCES OVERNIGHT...

.CURRENT OBSERVATIONS...
A LINE OF PRE FRONTAL SHOWERS CONTINUES TO MOVE EAST ACROSS EASTERN
NORTH DAKOTA. THE FRONT/TROUGH EXTENDS THROUGH CENTRAL NORTH DAKOTA
WITH ANOTHER LINE OF SHOWERS AND THUNDERSTORMS DEVELOPING ALONG IT.
A FEW CONVECTIVE SHOWERS HAVE DEVELOPED BEHIND THE BOUNDARY. MAIN
CHANGE BEHIND FRONT IS DRIER AIR AS TEMPERATURES ARE WARMER BEHIND
FRONT WITH THE AREA HAVING SEEN MORE SUN. A POOL OF 45 DEGREE
DEWPOINTS IS NOTED ACROSS THE NORTHERN RED RIVER VALLEY AND SHOULD
AID IN THUNDERSTORM DEVELOPMENT.

.SHORT TERM...
MAIN CONCERN WILL BE COVERAGE OF CONVECTION THIS EVENING ALONG THE
FRONT. NEW MESOETA AND RUC RUNS INDICATE THE GREATEST INSTABILITIES
ARE ACROSS THE NORTHERN PART OF THE FORECAST AREA(FA). THE AREA WILL
BE UNDER THE LEFT EXIT REGION OF A 500 MB JET...WHICH SHOULD HELP
ENHANCE LIFT. GIVEN LOW FREEZING LEVELS THIS EVENING...A FEW STORMS
MAY CONTAIN SOME SMALL HAIL. THE THUNDERSTORMS WILL MOVE OUT OF
EASTERN NORTH DAKOTA BY MIDNIGHT WITH SOME SHOWERS LINGERING INTO
THE MORNING HOURS OVER NORTHWEST MINNESOTA.

.MID TERM...
HIGH PRESSURE WILL MOVE INTO TO THE FA ON MONDAY AND WILL HELP PUSH
THE CLOUD COVER EAST OF THE REGION. CONVECTIVE TEMPERATURES ARE
WITHIN REACH DURING THE AFTERNOON...SO DO EXPECT SOME CUMULUS
DEVELOPMENT. THE RIDGE SETS UP OVER THE AREA MONDAY NIGHT AND WILL
LIGHT WINDS AND CLEAR SKIES TO MUCH OF THE AREA. THIS WILL ALLOW
TEMPERATURES TO FALL INTO THE LOW TO MID 30S BY TUESDAY MORNING.
EXPECT NEAR TO SLIGHTLY ABOVE SEASONAL TEMPERATURES TUESDAY AND
WEDNESDAY AS +8 TO +12 CELSIUS 850 MB TEMPERATURES MOVE IN. ANOTHER
CHANCE OF THUNDERSTORMS ON WEDNESDAY AS THE NEXT FRONT ENTERS THE
UPPER MIDWEST.

EXTENDED...LONG RANGE MODELS IN PRETTY GOOD AGREEMENT WITH MRF
COMPROMISE ON TIMING AND ECMWF SLOWEST. 500MB TROF DROPS THROUGH
AREA ON THU...SO KEPT CHANCE OF SHOWERS AND THUNDERSTORMS. THEN...
UPPER LEVEL RIDGE AND SFC HIGH BUILD INTO REGION THROUGH WEEKEND...
SO KEPT PRETTY MUCH DRY. AS FAR AS TEMPS...FMR WARMER THAN MEX...SO
LEANED TOWARDS MEX VALUES...KEEPING TEMPS AT OR BELOW NORMAL.

.FGF...NONE.

DONAVON/NG

The office that day

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

IssuedProductOfficeCountiesLasted
May 12, 5:12 PM CDTSevere Thunderstorm WarningFGFPembina33 min

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.