Alert archive / South Dakota / Tornado Warnings in 2017

Tornado Warning 22, NWS Aberdeen, SD

September 19, 20174 counties in South Dakota

NWS Aberdeen, SD issued this tornado warning at Sep 19, 2017, 9:54 PM CDT for 4 counties in South Dakota. It was in force for 15 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 19, 2017, 9:54 PM CDT (02:54 UTC)
Expired
Sep 19, 2017, 10:09 PM CDT
In force
15 min
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Codington County, SD, Day County, SD, Grant County, SD, Roberts County, SD

The radar

The Aberdeen radar (KABR), 100 km from the middle of the area, began a volume at 02:54 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Sep 19, 3:37 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 2.9 hours before the alert went out and 99 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, Aberdeen, SD at 00:00Z on 2017-09-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2563 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, Aberdeen, SD at 00:00Z on 2017-09-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 229 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
2563 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1127 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
229 m²/s²
0-3 km storm-relative helicity
239 m²/s²
Significant tornado parameter
2.6
Supercell composite
16.8

Open this sounding in Storm Lab

The text

As transmitted.

924 
WFUS53 KABR 200254
TORABR
SDC029-037-051-109-200330-
/O.NEW.KABR.TO.W.0022.170920T0254Z-170920T0330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Aberdeen SD
954 PM CDT TUE SEP 19 2017

The National Weather Service in Aberdeen has issued a

* Tornado Warning for...
  Southwestern Roberts County in northeastern South Dakota...
  Southeastern Day County in northeastern South Dakota...
  Northwestern Grant County in northeastern South Dakota...
  North central Codington County in northeastern South Dakota...

* Until 1030 PM CDT
    
* At 954 PM CDT, a severe thunderstorm capable of producing a tornado
  was located 7 miles southeast of Bitter Lake, or 17 miles southeast
  of Webster, moving northeast at 35 mph.

  HAZARD...Tornado. 

  SOURCE...Radar indicated rotation. 

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely. 

* This dangerous storm will be near...
  Ortley around 1010 PM CDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 4505 9722 4518 9740 4536 9715 4522 9698
TIME...MOT...LOC 0254Z 225DEG 31KT 4518 9723 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

Connelly
1 follow-up statement
455 
WWUS53 KABR 200309
SVSABR

Severe Weather Statement
National Weather Service Aberdeen SD
1009 PM CDT TUE SEP 19 2017

SDC029-037-051-109-200319-
/O.CAN.KABR.TO.W.0022.000000T0000Z-170920T0330Z/
Roberts SD-Day SD-Grant SD-Codington SD-
1009 PM CDT TUE SEP 19 2017

...THE TORNADO WARNING FOR SOUTHWESTERN ROBERTS...SOUTHEASTERN DAY...
NORTHWESTERN GRANT AND NORTH CENTRAL CODINGTON COUNTIES IS
CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.  However gusty winds and heavy rain are still
possible with this thunderstorm.

A tornado watch remains in effect until midnight CDT for northeastern
South Dakota.

LAT...LON 4505 9722 4518 9740 4536 9715 4522 9698
TIME...MOT...LOC 0308Z 225DEG 31KT 4527 9710 

$$

Connelly

The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 19, 7:01 PM CDTTornado WarningABRCampbell, Edmunds, McPherson, Walworth29 min
Sep 19, 7:23 PM CDTTornado WarningABRMcPherson20 min
Sep 19, 7:29 PM CDTSevere Thunderstorm WarningABRBrown, Marshall46 min
Sep 19, 7:40 PM CDTTornado Warning Tornado observedABRSpink35 min
Sep 19, 7:46 PM CDTSevere Thunderstorm WarningABRBrown, Spink44 min
Sep 19, 7:52 PM CDTTornado WarningABRMcPherson24 min
Sep 19, 8:12 PM CDTSevere Thunderstorm WarningABRBrown, Marshall33 min
Sep 19, 8:13 PM CDTTornado WarningABRClark, Spink32 min
Sep 19, 8:23 PM CDTSevere Thunderstorm WarningABRBrown, Day, Marshall, Spink37 min
Sep 19, 8:28 PM CDTTornado WarningABRClark, Spink32 min
Sep 19, 8:41 PM CDTSevere Thunderstorm WarningABRBrown, Marshall34 min
Sep 19, 8:53 PM CDTTornado WarningABRClark, Codington, Day, Spink37 min
Sep 19, 9:24 PM CDTTornado WarningABRClark, Codington, Day36 min
Sep 19, 10:43 PM CDTAreal Flood WarningABRCodington3 hr
Sep 19, 10:49 PM CDTSevere Thunderstorm WarningABRGrant, Roberts41 min
Sep 19, 11:26 PM CDTSevere Thunderstorm WarningABRGrant, Roberts19 min

Nearby

Tornado Warnings in South Dakota, 2017Every tornado warning in 2017Tornadoes in 2017

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.