Alert archive / South Dakota / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 75, NWS Rapid City, SD

July 11, 2017Meade County, Pennington County, South Dakota

NWS Rapid City, SD issued this severe thunderstorm warning at Jul 11, 2017, 2:51 PM MDT for Meade County, Pennington County, South Dakota. It was in force for 38 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 11, 2017, 2:51 PM MDT (20:51 UTC)
Expired
Jul 11, 2017, 3:29 PM MDT
In force
38 min
Issued by
NWS Rapid City, SD
Area
Storm-based polygon
Hail
1.5 in
Wind
60.0 mph

Counties Meade County, SD, Pennington County, SD

The radar

The Rapid City radar (KUDX), 18 km from the middle of the area, began a volume at 20:50 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

Bismarck Municip, ND (KBIS), launched 12:00Z, 8.9 hours before the alert went out and 320 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 2017-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 34 joules per kilogram.LCLLFCEL10008507005003002001001 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, Bismarck Municip, ND at 12:00Z on 2017-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 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
34 J/kg
Mixed-layer CIN
-303 J/kg
Mixed-layer LCL
2064 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
145 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 Rapid City, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 11, 1:46 PM MDT, 1 hour 5 minutes earlier.

Area forecast discussion, Jul 11, 1:46 PM MDT, 1 hour 5 minutes before
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
146 PM MDT Tue Jul 11 2017

.DISCUSSION...(This Evening Through Tuesday)
Issued at 133 PM MDT Tue Jul 11 2017

Upper level analysis has mainly zonal flow across the northern
Rockies and northern Plains. Skies are clear with the exception of
some cumulus development and towering cumulus over the Black
Hills. At the surface, low pressure was located across southwest
Manitoba, with a cold front running south through central ND and
western SD. Temperatures at 2PM across the forecast area are in
the mid 80s to upper 90s, and winds are breezy northwest behind
the front, and breezy west to southwest ahead.

Tonight into Wednesday...There will be a better chance for
showers and a few storms tonight and early Wednesday as the next
disturbance passes over the area. With instability relatively low
across much of the the area overnight, shower activity should be
on the light side.

Wednesday will be a little cooler behind the front, with highs in
the mid 80s to lower 90s. After morning shower activity tapers
off, there will be a chance for afternoon and evening
thunderstorms across much of the area. A few storms could be on
the strong side, with gusty winds and hail, especially across the
Black Hills and adjacent plains.

The rest of the week and the weekend look to be on the drier side,
with mostly isolated thunderstorm activity expected at times,
especially over the Black Hills. The heat will return as the ridge
and high pressure rebuild over the intermountain west and the
Rockies. Highs will be back in the 90s to around 100 from Thursday
through the weekend, with triple digit highs a good possibility
across much of the plains early next week.

.AVIATION...(For the 18Z TAFS Through 18Z Wednesday)
Issued At 133 PM MDT Tue Jul 11 2017

VFR conditions will prevail through much of the period. Another
impulse will bring SCT-ISOLD TS to the area this evening and
overnight. Gusty winds can be expected in/near any TS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Heat Advisory until 7 PM CDT this evening for SDZ049.

WY...None.
&&

DISCUSSION...15
AVIATION...13
Hazardous weather outlook, Jul 11, 5:33 AM MDT, 9 hours 18 minutes before
Hazardous Weather Outlook
National Weather Service Rapid City SD
533 AM MDT Tue Jul 11 2017

SDZ001-002-012>014-024>032-041>044-046-047-072>074-WYZ054>058-071-
121300-
Harding-Perkins-Butte-Northern Meade Co Plains-Ziebach-
Northern Black Hills-Northern Foot Hills-Rapid City-
Southern Foot Hills-Central Black Hills-Southern Black Hills-
Custer Co Plains-Pennington Co Plains-Haakon-Fall River-
Oglala Lakota-Jackson-Bennett-Mellette-Todd-
Sturgis/Piedmont Foot Hills-Southern Meade Co Plains-
Hermosa Foot Hills-Northern Campbell-Southern Campbell-
Western Crook-Wyoming Black Hills-Weston-Northeastern Crook-
533 AM MDT Tue Jul 11 2017 /633 AM CDT Tue Jul 11 2017/

This Hazardous weather outlook is for portions of south central
South Dakota...the Black Hills of South Dakota...western South
Dakota...northeast Wyoming...and the Black Hills of Wyoming.

.DAY ONE...Today and Tonight

Hot temperatures will continue with highs in the 90s to around
100.

The grassland fire danger index will reach the high to very high
categories this afternoon on the South Dakota Plains.

Isolated thunderstorms will be possible mainly this evening and
overnight. Strong winds will be the main threat from
thunderstorms.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Hot and mainly dry weather will continue. Isolated thunderstorms
are possible at times. Isolated strong to severe storms will be
possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

SDZ049-121300-
Tripp-
633 AM CDT Tue Jul 11 2017

This Hazardous weather outlook is for portions of south central
South Dakota.

.DAY ONE...Today and Tonight

A heat advisory is in effect today as heat indices of 100 to 103
are expected this afternoon.

The grassland fire danger index will reach the high category this
afternoon.

Isolated thunderstorms will be possible mainly tonight. Strong
winds will be the main threat from thunderstorms

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Hot and mainly dry weather will continue. Isolated thunderstorms
are possible at times. Isolated strong to severe storms will be
possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

In the hours before

Special weather statement, Jul 11, 2:28 PM MDT, 23 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 10, 8:37 PM MDTSpecial Weather StatementUNRHarding38 min
Jul 10, 9:15 PM MDTSpecial Weather StatementUNRHarding45 min
Jul 11, 3:44 AM MDTHeat AdvisoryUNRTripp14 hr
Jul 11, 2:28 PM MDTSpecial Weather StatementUNRPennington47 min
Jul 11, 3:24 PM MDTSpecial Weather StatementUNRPennington51 min
Jul 11, 3:42 PM MDTSpecial Weather StatementUNRPennington33 min
Jul 11, 3:49 PM MDTSevere Thunderstorm WarningUNRCuster, Oglala Lakota, Pennington56 min
Jul 11, 4:44 PM MDTSevere Thunderstorm WarningUNRJackson, Oglala Lakota, Pennington46 min
Jul 11, 5:25 PM MDTSpecial Weather StatementUNRJackson50 min
Jul 10, 8:35 PM MDTSpecial Weather StatementUNRCampbell, Crook25 min
Jul 10, 8:58 PM MDTSpecial Weather StatementUNRCampbell, Crook47 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2017Every severe thunderstorm warning 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.