Alert archive / North Dakota / Special Weather Statements in 2021

Special Weather Statement, NWS Grand Forks, ND

August 20, 2021Griggs County, North Dakota

NWS Grand Forks, ND issued this special weather statement at Aug 20, 2021, 3:49 PM CDT for Griggs County, North Dakota. It was in force for 56 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
Aug 20, 2021, 3:49 PM CDT (20:49 UTC)
Expired
Aug 20, 2021, 4:45 PM CDT
In force
56 min
Issued by
NWS Grand Forks, ND
Hail
0.00 in
Wind
40

County Griggs County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 72 km from the middle of the area, began a volume at 20:53 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
Aug 20, 4:32 PM CDTFUNNEL CLOUD6 Nnw Luverne, NDPERSISTENT WALL CLOUD WITH BRIEF FUNNEL.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 8.8 hours before the alert went out and 202 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, Bismarck Municip, ND at 12:00Z on 2021-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 306 joules per kilogram.LCLLFCEL10008507005003002001001 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, Bismarck Municip, ND at 12:00Z on 2021-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 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
306 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
609 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

893 
WWUS83 KFGF 202049
SPSFGF

Special Weather Statement
National Weather Service Grand Forks ND
349 PM CDT Fri Aug 20 2021
 
NDZ028-029-038-202145-
Griggs ND-Steele ND-Barnes ND-
349 PM CDT Fri Aug 20 2021

...A strong thunderstorm will impact portions of southeastern Griggs,
northwestern Barnes and southwestern Steele Counties through 445 PM
CDT...

At 348 PM CDT, Doppler radar was tracking a strong thunderstorm near
Bald Hill Dam, or 9 miles northwest of Valley City, moving northeast
at 20 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

This strong thunderstorm will be near...
  Bald Hill Dam and Rogers around 355 PM CDT.

Other locations in the path of this storm include Dazey, Sibley and
Luverne.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
southeastern North Dakota.

&&

LAT...LON 4696 9813 4700 9832 4750 9820 4730 9769
TIME...MOT...LOC 2048Z 208DEG 18KT 4702 9815 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

$$

CJ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 9:47 AM CDTSpecial Weather StatementFGFGrand Forks28 min
Aug 20, 11:04 AM CDTAreal Flood AdvisoryFGFGrand Forks4 hr
Aug 20, 11:12 AM CDTSpecial Weather StatementFGFCass33 min
Aug 20, 2:43 PM CDTTornado WarningFGFBarnes, Cass47 min
Aug 20, 3:24 PM CDTSpecial Weather StatementFGFCass36 min
Aug 20, 4:00 PM CDTSpecial Weather StatementFGFTraill60 min
Aug 20, 4:11 PM CDTTornado WarningFGFBarnes, Griggs, Steele49 min
Aug 20, 4:13 PM CDTTornado WarningFGFCass, Traill47 min
Aug 20, 4:49 PM CDTSevere Thunderstorm WarningFGFTraill26 min
Aug 20, 4:51 PM CDTSpecial Weather StatementFGFSteele54 min
Aug 20, 5:11 PM CDTSpecial Weather StatementFGFRamsey49 min
Aug 20, 5:13 PM CDTSevere Thunderstorm Warning Considerable damage threatFGFGrand Forks, Traill39 min
Aug 20, 6:24 PM CDTSpecial Weather StatementFGFWalsh51 min
Aug 20, 12:28 PM CDTSpecial Weather StatementFGFNorman, Polk32 min
Aug 20, 1:02 PM CDTSpecial Weather StatementFGFPennington, Red Lake28 min
Aug 20, 1:09 PM CDTSevere Thunderstorm WarningFGFPennington, Polk, Red Lake51 min
Aug 20, 1:53 PM CDTSevere Thunderstorm WarningFGFBeltrami, Clearwater, Lake of the Woods, Marshall, Pennington67 min
Aug 20, 2:00 PM CDTSpecial Weather StatementFGFRoseau60 min
Aug 20, 2:52 PM CDTSpecial Weather StatementFGFLake of the Woods53 min
Aug 20, 3:31 PM CDTSpecial Weather StatementFGFGrant59 min
Aug 20, 4:12 PM CDTSpecial Weather StatementFGFWadena33 min
Aug 20, 4:19 PM CDTSpecial Weather StatementFGFBeltrami26 min
Aug 20, 4:20 PM CDTSpecial Weather StatementFGFBeltrami25 min
Aug 20, 4:22 PM CDTSpecial Weather StatementFGFClay53 min
Aug 20, 4:43 PM CDTSpecial Weather StatementFGFBeltrami32 min
Aug 20, 5:07 PM CDTSevere Thunderstorm WarningFGFOtter Tail, Wadena38 min

Nearby

Special Weather Statements in North Dakota, 2021Every special weather statement in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.