Severe Thunderstorm Warning 259, NWS Sioux Falls, SD

170 
WWUS53 KFSD 222306
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
606 PM CDT FRI SEP 22 2017

SDC087-222316-
/O.CAN.KFSD.SV.W.0259.000000T0000Z-170922T2315Z/
McCook SD-
606 PM CDT FRI SEP 22 2017

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MCCOOK COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4404 9689 4383 9689 4375 9713 4387 9713
TIME...MOT...LOC 2306Z 229DEG 32KT 4388 9699 

$$

SDC079-099-222315-
/O.CON.KFSD.SV.W.0259.000000T0000Z-170922T2315Z/
Lake SD-Minnehaha SD-
606 PM CDT FRI SEP 22 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CDT
FOR SOUTHEASTERN LAKE AND NORTHWESTERN MINNEHAHA COUNTIES...

At 606 PM CDT, a severe thunderstorm was located near Chester, or 10
miles southeast of Madison, moving northeast at 35 mph.

HAZARD...60 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

This severe storm will be near...
  Chester around 610 PM CDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4404 9689 4383 9689 4375 9713 4387 9713
TIME...MOT...LOC 2306Z 229DEG 32KT 4388 9699 

HAIL...1.00IN
WIND...60MPH
 
$$

Weisser

512 
WWUS53 KFSD 222312
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
612 PM CDT FRI SEP 22 2017

SDC079-099-222322-
/O.EXP.KFSD.SV.W.0259.000000T0000Z-170922T2315Z/
Lake SD-Minnehaha SD-
612 PM CDT FRI SEP 22 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LAKE AND
NORTHWESTERN MINNEHAHA COUNTIES WILL EXPIRE AT 615 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire.

LAT...LON 4404 9689 4383 9689 4375 9713 4387 9713
TIME...MOT...LOC 2312Z 229DEG 32KT 4392 9693 

$$

Weisser

Area Forecast Discussion
National Weather Service Sioux Falls SD
541 PM CDT Fri Sep 22 2017

.SHORT TERM...(This evening through tonight) Issued at 322 PM CDT
Fri Sep 22 2017

The Northern Plains continues to sit under strong southwesterly flow
aloft, between the upper level trough over the Western U.S., and a
large scale ridge over the eastern states. At the surface, this has
allowed warm moist air to continue streaming northward, bringing
gusty winds and near record heat to the area. Those with outdoor
plans this afternoon will want to stay hydrated and take steps to
avoid heat exhaustion in the summer-like heat.

Despite bountiful CAPE this afternoon, a strong capping inversion
has suppressed convection over the area. In fact, even cumulus
clouds have been scarce due to the strength of the 700 to 800 hPa
warm layer. Models show a shortwave trough moving northward this
evening which will likely be able to erode the cap sufficiently and
provide lift to allow thunderstorm formation over southeast South
Dakota. These storms are expected to then move northeastward,
staying roughly north and west of a Yankton, SD to Sioux Falls to
Marshall, MN line. The time period with greatest likelihood for
thunderstorms should be 6-11pm CDT. The threat for severe storms is
only marginal, with lightning and strong outflow winds being the
more widespread threats. Further to the southeast in NW Iowa, the
air mass will likely remain capped, and storms are not expected
here.

.LONG TERM...(Saturday through Friday) Issued at 322 PM CDT Fri
Sep 22 2017

The weekend continues to look very wet, with many locations likely
seeing one to two inches of rain over a 72-hour period as a quasi-
stationary boundary sets up over the region. An air mass with 1.5
inch plus precipitable water values will continue to fuel showers
and scattered thunderstorms along this boundary as the large scale
upper level trough slowly pushes east over the weekend. West of I-
29, the heaviest rain looks to move through Saturday afternoon and
evening. The severe threat is only marginal Saturday, as the
strongest shear is expected to remain west of the surface boundary
during the afternoon, and lapse rates are only marginal, at about
7 C/km. For locations east of I-29, Sunday afternoon and evening
look most favorable for the heaviest rain. Temperatures Saturday
and Sunday will not be as warm as on Friday, as abundant cloud
cover limits heating and cooler air slowly pushes in from the
northwest. The boundary and focus for rain move east into
southwest MN and northwest IA on Monday, with rain chances
decreasing for eastern SD.

By the PM hours Tuesday, northwest surface flow in the wake of the
front is forecast to dry the boundary layer and bring an end to
precipitation. A large scale pattern change with the shifting east
of the upper level longwave trough will bring quieter weather and
closer to seasonal temperatures for the middle to end of next
week.

&&

.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 535 PM CDT Fri Sep 22 2017

Scattered thunderstorms will be possible through the James River
Valley into east central SD during the overnight hours. There will
be a period of low level wind shear at KSUX later tonight as a low
level jet develops across the region. Shower and thunderstorm
chances will continue on Saturday roughly over the same areas,
with better coverage on Saturday afternoon.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Heat Advisory until 6 PM CDT this evening for SDZ056-062-066-067-
     069>071.

MN...Heat Advisory until 6 PM CDT this evening for MNZ071-072-080-081-
     089-090-097-098.

IA...Heat Advisory until 6 PM CDT this evening for IAZ001>003-012>014-
     020>022-031-032.

NE...Heat Advisory until 6 PM CDT this evening for NEZ013-014.

&&

SHORT TERM...VandenBoogart
LONG TERM...VandenBoogart
AVIATION...JM

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
103 PM CDT Fri Sep 22 2017

SDZ038>040-050-052>055-057>061-063>065-068-231815-
Beadle-Kingsbury-Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-
Brule-Aurora-Davison-Hanson-McCook-Charles Mix-Douglas-Hutchinson-
Bon Homme-
103 PM CDT Fri Sep 22 2017

This Hazardous Weather Outlook is for portions of central South
Dakota, east central South Dakota, south central South Dakota,
and southeast South Dakota.

.DAY ONE...This Afternoon and Tonight

There is a marginal chance for severe weather this evening across
southeastern South Dakota and parts of southwest Minnesota. Hail
up to half dollar size and wind gusts up to 60 mph are possible
with any severe storms that develop. Additionally, an isolated
tornado cannot be ruled out.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Rainfall chances will continue into early next week, with the
threat for periods of heavy rainfall beginning early Saturday.
Rainfall could potentially total several inches of rain for some
areas over the three day period ending Monday night. Accordingly,
there is a threat for significant ponding of water and some flash
flooding.

Some severe weather is possible Saturday and Sunday. However, location
of the severe weather threat both Saturday and Sunday remains
difficult to determine, dependent on exactly where the front sets
up.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ056-062-066-067-069>071-231815-
Lyon IA-Osceola-Dickinson-Sioux-O'Brien-Clay IA-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln MN-Lyon MN-Murray-Cottonwood-
Nobles-Jackson-Pipestone-Rock-Dixon-Dakota-Moody-Minnehaha-Turner-
Lincoln SD-Yankton-Clay SD-Union-
103 PM CDT Fri Sep 22 2017

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

.DAY ONE...This Afternoon and Tonight

Heat and humidity will create heat indices of 95 to 100 degrees
through the afternoon into the early evening hours.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Thunderstorm risks will return by Saturday and continue at times
into early next week. At this time, while a widespread severe
weather risk is unlikely, an isolated strong to severe storm
appears possible Saturday or Sunday, depending on exactly where
the front sets up. In addition, some areas of heavy rainfall are
likely, along with a risk for significant ponding or flash
flooding, especially near and west of a Windom to Sioux City line.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
519 PM CDT FRI SEP 22 2017

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

0514 PM     HAIL             8 NNE SALEM             43.83N 97.33W
09/22/2017  E0.88 INCH       MCCOOK             SD   PUBLIC

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
526 PM CDT FRI SEP 22 2017

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

0508 PM     HAIL             6 N SALEM               43.81N 97.37W
09/22/2017  E1.00 INCH       MCCOOK             SD   PUBLIC

&&

PS