Damaging Wind in South Dakota, June 29, 2018

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
536 PM MDT Fri Jun 29 2018

.DISCUSSION...(This Evening Through Friday)
Issued at 318 PM MDT Fri Jun 29 2018

Current surface analysis shows low pressure over southeast SD,
with cold front now just east of the forecast area. Upper level
analysis shows large scale trough centered over the Northern
Rockies, with southwest flow over the Northern Plains. Skies are
variably cloudy across the area, the most sun to the east of the
Black Hills. Temps right now are in the mid 70s to mid 80s.
Thunderstorms have developed over northeast WY, with a couple
being severe right now. More showers and storms are developing
further south across eastern WY. Activity is moving east-
northeast.

A favorable severe weather threat remains in place through this
evening as storms spread east across the rest of the area. A good
amount of moisture in the low to mid levels remains across the area,
with SBCAPE values ranging from around 1500 j/kg over northeast WY
to over 2000 j/kg over parts of southwest and south central SD.
Shear is sufficient for supercells, especially across western and
southern portions of the forecast area. Cap looks to remain strong
to the east of the Black Hills this afternoon, with most of the
activity moving into these areas this evening. There is a strong
likelihood that the activity will consolidate into a MCS as it moves
into/through western SD late this afternoon and this evening. Main
threats with severe storms will be large hail and strong wind gusts,
but an isolated tornado threat is also expected from northeast WY to
southwest SD.

Saturday looks to be cool, mainly cloudy. and showery, especially
across the Black Hills and southern SD, as the trough moves across
the Northern Plains. Some thunderstorms are also expected,
especially across southern SD. A strong storm or two is possible
toward south central SD, but the severe threat looks minimal at this
time. Highs will only be in the upper 60s to upper 70s. Showers will
end Saturday evening with a dry and seasonably warm Sunday on tap.
Highs on Sunday will be in the mid 70s to mid 80s.

Next week looks to be very warm to hot with mainly dry conditions
for most areas as a ridge builds over the Plains into the midwest
states. Temperatures will be above average for much of the week,
highs in the 80s and 90s, with Independence Day possibly being the
warmest day of the week. Southwest flow on the back side of the
ridge could bring weak energy aloft at times with mainly isolated
storms possible, especially mid to late week.

&&

.AVIATION...(For the 00Z TAFS Through 00Z Saturday Evening)
Issued At 536 PM MDT Fri Jun 29 2018

Showers and thunderstorms will continue to track east across
western SD this evening, some likely severe with hail and very strong
winds. Areas of MVFR and brief IFR conditions are expected in the
stronger storms early this evening. Isolated to scattered showers
and storms are then expected overnight into Saturday, mainly from
northeast WY to southern SD. Areas of MVFR/IFR conditions are
expected late tonight into Saturday morning.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

DISCUSSION...26
AVIATION...26

Hazardous Weather Outlook
National Weather Service Rapid City SD
238 AM MDT Fri Jun 29 2018

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-301300-
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-Tripp-
Sturgis/Piedmont Foot Hills-Southern Meade Co Plains-
Hermosa Foot Hills-Northern Campbell-Southern Campbell-
Western Crook-Wyoming Black Hills-Weston-Northeastern Crook-
238 AM MDT Fri Jun 29 2018 /338 AM CDT Fri Jun 29 2018/

This Hazardous Weather Outlook is for western South Dakota and
northeastern Wyoming.

.DAY ONE...Today and Tonight

Numerous thunderstorms will move across the area this afternoon
into tonight. There is a slight risk of severe thunderstorms with
large hail and damaging winds.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

There is a chance of thunderstorms Saturday, mainly south of
Interstate 90. Severe thunderstorms are not expected at this time.

.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

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
638 PM MDT FRI JUN 29 2018

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

0442 PM     HAIL             LEAD                    44.35N 103.77W
06/29/2018  M3.00 INCH       LAWRENCE           SD   PUBLIC

            BROKEN HOUSE WINDOWS

&&

JJ

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
639 PM MDT FRI JUN 29 2018

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

0630 PM     HAIL             EDGEMONT                43.30N 103.83W
06/29/2018  M1.00 INCH       FALL RIVER         SD   TRAINED SPOTTER

            LOT OF PEA SIZE HAIL WITH SOME QUARTER

&&

AFOSCATO

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
644 PM MDT FRI JUN 29 2018

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

0624 PM     HAIL             12 S FAITH              44.85N 102.04W
06/29/2018  E1.00 INCH       MEADE              SD   TRAINED SPOTTER

0624 PM     TSTM WND GST     12 S FAITH              44.85N 102.04W
06/29/2018  E60 MPH          MEADE              SD   TRAINED SPOTTER

&&

AFOSCATO

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
647 PM MDT FRI JUN 29 2018

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

0624 PM     TSTM WND GST     3 WSW FAIRBURN          43.68N 103.26W
06/29/2018  M58 MPH          CUSTER             SD   DEPT OF HIGHWAYS

&&

JJ

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
654 PM MDT FRI JUN 29 2018

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

0644 PM     HAIL             4 SE WIND CAVE VISITORS 43.52N 103.40W
06/29/2018  M1.50 INCH       CUSTER             SD   TRAINED SPOTTER

&&

KCLARK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
703 PM MDT FRI JUN 29 2018

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

0644 PM     TSTM WND GST     2 SW BRIDGER            44.53N 101.93W
06/29/2018  M63 MPH          ZIEBACH            SD   DEPT OF HIGHWAYS

&&

JJ