Alert archive / South Dakota / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 119, NWS Sioux Falls, SD

July 6, 2020Aurora County, Brule County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 6, 2020, 10:42 PM CDT for Aurora County, Brule County, South Dakota. It was in force for 34 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 6, 2020, 10:42 PM CDT (03:42 UTC)
Expired: Jul 6, 2020, 11:16 PM CDT
In force: 34 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 1.25 in
Wind: 50.0 mph

Counties Aurora County, SD, Brule County, SD

The radar

The Sioux Falls radar (KFSD), 169 km from the middle of the area, began a volume at 03:45 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 nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 3.7 hours before the alert went out and 323 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 450 J/kg
Mixed-layer CIN: -162 J/kg
Mixed-layer LCL: 2603 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: -10 m²/s²
0-3 km storm-relative helicity: 111 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

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 Sioux Falls, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 6, 6:52 PM CDT, 3 hours 50 minutes earlier.

Area forecast discussion, Jul 6, 6:52 PM CDT, 3 hours 50 minutes before

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Hazardous weather outlook, Jul 6, 5:24 AM CDT, 17 hours 18 minutes before

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
524 AM CDT Mon Jul 6 2020

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-071030-
Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson-
Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-Brookings-Gregory-
Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora-Davison-Hanson-McCook-
Minnehaha-Charles Mix-Douglas-Hutchinson-Turner-Bon Homme-Yankton-
Union-
524 AM CDT Mon Jul 6 2020

This Hazardous Weather Outlook is for northwest Iowa, west central
Iowa, southwest Minnesota, northeast Nebraska, central South
Dakota, east central South Dakota, south central South Dakota and
southeast South Dakota.

.DAY ONE...Today and tonight.

Thunderstorms are possible this morning. A few of the stronger storms
may produce gusty winds to 50 mph. Additional thunderstorms are
expected after 2 PM this afternoon. Some of these storms may produce
hail to the size of half dollars, and wind gusts to 65 mph.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Heat index values are expected to climb into the 90s each afternoon
this week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed after 2 pm today.

In the hours before

Local storm report, Jul 6, 7:24 PM CDT, 3 hours 18 minutes before

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Local storm report, Jul 6, 8:12 PM CDT, 2 hours 30 minutes before

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Local storm report, Jul 6, 8:39 PM CDT, 2 hours 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
839 PM CDT MON JUL 6 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0519 PM     TSTM WND DMG     3 S GAYVILLE            42.84N 97.16W
07/06/2020                   YANKTON            SD   TRAINED SPOTTER

            A PINE TREE WITH TRUNK DIAMETER OF 6 FEET
            WAS DOWNED DUE TO THE STRONG THUNDERSTORM
            WIND GUSTS.

&&

AT

Local storm report, Jul 6, 8:53 PM CDT, 1 hour 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
853 PM CDT MON JUL 6 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0551 PM     TSTM WND GST     MASKELL                 42.69N 96.98W
07/06/2020  E60 MPH          DIXON              NE   PUBLIC

            SOME PEA SIZED HAIL ALSO.

&&

Local storm report, Jul 6, 9:09 PM CDT, 1 hour 33 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
909 PM CDT MON JUL 6 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0534 PM     HAIL             5 SSW MECKLING          42.77N 97.11W
07/06/2020  E1.25 INCH       CLAY               SD   PUBLIC

            STRONG WINDS ACCOMPANIED THE HAIL, BUT NO
            ESTIMATES ON STRENGTH AND NO VISIBLE DAMAGE.

&&

AT

Local storm report, Jul 6, 9:30 PM CDT, 1 hour 12 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE SIOUX FALLS SD
930 PM CDT MON JUL 6 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0645 PM     TSTM WND GST     3 SE JEFFERSON          42.57N 96.53W
07/06/2020  M50 MPH          UNION              SD   MESONET

            MESONET STATION 53 SD RWIS NORTH SIOUX CITY.

0645 PM     HEAVY RAIN       NEWCASTLE               42.65N 96.87W
07/06/2020  M2.20 INCH       DIXON              NE   TRAINED SPOTTER

            SOME PEA-SIZED HAIL AS WELL, BUT MOSTLY
            HEAVY RAIN WITH VAST MAJORITY OF THE
            RAINFALL WITHIN THE PAST HOUR.

0644 PM     TSTM WND GST     1 SE NORTH SIOUX CITY   42.53N 96.49W
07/06/2020  M60 MPH          UNION              SD   TRAINED SPOTTER

0634 PM     TSTM WND GST     PONCA                   42.57N 96.71W
07/06/2020  E65 MPH          DIXON              NE   TRAINED SPOTTER

            PENNY-SIZED HAIL AND HEAVY RAIN IN ADDITION
            TO THE STRONG WINDS.

0628 PM     TSTM WND GST     1 W PONCA               42.57N 96.73W
07/06/2020  M67 MPH          DIXON              NE   TRAINED SPOTTER

0551 PM     TSTM WND GST     MASKELL                 42.69N 96.98W
07/06/2020  E60 MPH          DIXON              NE   PUBLIC

            SOME PEA SIZED HAIL ALSO.

0542 PM     HAIL             4 S MASKELL             42.63N 96.98W
07/06/2020  E0.88 INCH       DIXON              NE   TRAINED SPOTTER

            ESTIMATED WIND GUSTS TO 50 MPH.

0534 PM     HAIL             5 SSW MECKLING          42.77N 97.11W
07/06/2020  E1.25 INCH       CLAY               SD   PUBLIC

            STRONG WINDS ACCOMPANIED THE HAIL, BUT NO
            ESTIMATES ON STRENGTH AND NO VISIBLE DAMAGE.

0530 PM     TSTM WND GST     1 S MECKLING            42.83N 97.07W
07/06/2020  E50 MPH          CLAY               SD   LAW ENFORCEMENT

0519 PM     TSTM WND DMG     3 S GAYVILLE            42.84N 97.16W
07/06/2020                   YANKTON            SD   TRAINED SPOTTER

            A PINE TREE WITH TRUNK DIAMETER OF 6 FEET
            WAS DOWNED DUE TO THE STRONG THUNDERSTORM
            WIND GUSTS.

0510 PM     TSTM WND GST     2 WSW GAYVILLE          42.88N 97.22W
07/06/2020  M66 MPH          YANKTON            SD   MESONET

            MESONET STATION 197 SD RWIS GAYVILLE.

0504 PM     TSTM WND GST     MISSION HILL            42.92N 97.28W
07/06/2020  E60 MPH          YANKTON            SD   TRAINED SPOTTER

            DIME SIZED HAIL AND HEAVY RAIN ALONG WITH
            STRONG WINDS.

0451 PM     HAIL             3 NW MISSION HILL       42.95N 97.32W
07/06/2020  M0.88 INCH       YANKTON            SD   LAW ENFORCEMENT

            CROPS STRIPPED TO STEM.

0442 PM     TSTM WND GST     2 NE YANKTON            42.92N 97.37W
07/06/2020  M68 MPH          YANKTON            SD   AWOS

            AWOS STATION KYKN YANKTON MUNICIPAL AIRPORT.

0440 PM     TSTM WND DMG     5 N YANKTON             42.96N 97.40W
07/06/2020                   YANKTON            SD   PUBLIC

            A COUPLE OF LARGE TREES TOPPLED. REPORTED AT
            30546 HWY 81 YANKTON SD.

0430 PM     FLASH FLOOD      8 E PARKSTON            43.39N 97.82W
07/06/2020                   HUTCHINSON         SD   LAW ENFORCEMENT

            MULTIPLE INCHES OF WATER FLOWING OVER HWY
            44, WITH ROAD TEMPORARILY BLOCKED BY LAW
            ENFORCEMENT.

0418 PM     TSTM WND GST     5 NE TYNDALL            43.04N 97.79W
07/06/2020  E60 MPH          BON HOMME          SD   TRAINED SPOTTER

            A COUPLE OF 4 INCH DIAMETER TREE LIMBS DOWN.

0348 PM     HAIL             6 SW SCOTLAND           43.08N 97.79W
07/06/2020  E1.25 INCH       BON HOMME          SD   PUBLIC

            REPORTED AT 29726 420TH AVVENUE SCOTLAND SD.

0248 PM     HAIL             4 S CLAYTON             43.38N 97.66W
07/06/2020  E1.00 INCH       HUTCHINSON         SD   PUBLIC

            REPORTED AT 27609 427TH AVENUE FREEMAN SD.

0242 PM     HAIL             6 SW CLAYTON            43.37N 97.73W
07/06/2020  E0.70 INCH       HUTCHINSON         SD   PUBLIC

            REPORTED AT 27718 423RD AVENUE PARKSTON SD.

0225 PM     HAIL             7 SW CLAYTON            43.38N 97.76W
07/06/2020  E1.00 INCH       HUTCHINSON         SD   PUBLIC

            REPORTED AT 42199 HWY 44 PARKSTON SD.

0205 PM     HAIL             4 SSW TABOR             42.90N 97.69W
07/06/2020  E1.00 INCH       BON HOMME          SD   TRAINED SPOTTER

            HEAVY RAIN AND SOME WIND, BUT NO DAMAGE.

0200 PM     HAIL             ALEXANDRIA              43.65N 97.78W
07/06/2020  E2.75 INCH       HANSON             SD   LAW ENFORCEMENT

0200 PM     HAIL             1 NNW ALEXANDRIA        43.66N 97.79W
07/06/2020  E1.50 INCH       HANSON             SD   LAW ENFORCEMENT

            PING PONG BALL SIZED HAIL AT THE I-90 EXIT
            FOR ALEXANDRIA.

0143 PM     HAIL             2 ESE FULTON            43.72N 97.79W
07/06/2020  E1.50 INCH       HANSON             SD   TRAINED SPOTTER

            HEAVY RAIN AND BRIEFLY GUSTY WINDS PRECEDED
            THE LARGE HAIL.

&&

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 6, 10:21 PM CDT	Severe Thunderstorm Warning	FSD	Douglas	24 min
Jul 6, 10:46 PM CDT	Severe Thunderstorm Warning	FSD	Charles Mix, Douglas	44 min
Jul 6, 11:05 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Douglas	40 min
Jul 6, 11:35 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule	25 min
Jul 6, 11:45 PM CDT	Flash Flood Watch	FSD	Aurora, Bon Homme, Brule, Charles Mix, Davison, Douglas and 3 more	5 hr
Jul 7, 12:26 AM CDT	Flash Flood Warning	FSD	Aurora, Brule, Charles Mix, Davison, Douglas	5 hr
Jul 7, 12:28 AM CDT	Severe Thunderstorm Warning	FSD	Brule, Charles Mix, Gregory	47 min
Jul 7, 1:06 AM CDT	Flash Flood Warning	FSD	Bon Homme, Charles Mix, Hutchinson	4 hr
Jul 7, 1:06 AM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Charles Mix, Davison, Douglas, Gregory	39 min
Jul 7, 1:45 AM CDT	Severe Thunderstorm Warning	FSD	Bon Homme, Charles Mix, Douglas, Gregory, Hutchinson	45 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2020 Every severe thunderstorm warning in 2020

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.