Strong low-level flow ahead of an eastward advancing front combined with scattered showers to produce sporadic high winds across southeast South Dakota on May 14.
Every event with a place to put it; 4 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS FSD wrote it up.
Strong low-level flow ahead of an eastward advancing front combined with scattered showers to produce sporadic high winds across southeast South Dakota on May 14.
The local office's own words before the first event, 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 the first event at May 14, 2:46 AM CST, 44 minutes earlier. Its key messages:
Area Forecast Discussion
National Weather Service Sioux Falls SD
346 AM CDT Thu May 14 2026
.KEY MESSAGES...
- Critical fire weather expected today; Red Flag Warning east of
US Highway 281 from 10 AM to 7 PM CDT. Use extreme caution to
prevent fire start.
- Isolated showers and thunderstorms are possible today, mainly
east of I-29. Severe storms are not expected.
- Winds today gust 35-45 mph, with a few stronger gusts possible
between the James River Valley and I-29. Strong winds lead to
periods of blowing dust in rural areas. Use caution if
traveling as visibility may be impacted.
- Temperatures warm though the weekend, with high temperatures
10 to 20 degrees above normal.
- Regional rain chances increase late Saturday and especially
Sunday. Uncertainty lingers, but signals remain for strong
storms Saturday and continuing risks Sunday and Monday.
&&
.UPDATE...
Issued at 343 AM CDT Thu May 14 2026
Mid/high clouds are increasing across central SD, moving east with
the mid/upper level wave this morning. Winds and gusts are already
on the increase as well with the tightening SPG ahead of the surface
low ejecting into western SD/NE. Although seeing some returns on
radar out west, have not seen any reports of precip reaching the
ground, likely due to the very dry sub cloud layer.
No significant changes to the forecast from the previous shift as
the trough continues to move east through the day. Refined pops
slightly based on some of the latest CAM guidance, but still think
any showers/storms remain isolated in nature.
Strong winds today will gust 35-45 mph. Guidance still shows
isolated stronger gusts around 50 mph, mainly between the James
River Valley and I-29, as well as across the higher elevations of
the Buffalo Ridge and Coteau. Although not anticipating any wind
headlines, will continue to monitor. Strong winds likely lead to
blowing dust and possible visibility restrictions, especially in
rural areas. Red Flag Warning in effect from 10 AM to 7 PM CDT east
of US Hwy 281; more details in the Fire Weather Section below. Use
extreme caution to prevent a spark and report fires to local
authorities.
&&
.DISCUSSION...
Issued at 155 PM CDT Wed May 13 2026
THIS AFTERNOON: An absolutely beautiful afternoon across the region
as winds remain light and variable, temperatures have risen into the
70s and plenty of sunshine is around. Expect these conditions to
persist into the evening.
TONIGHT: Shortwave ridging moves east of I-29 by daybreak
Thursday, with modest low-lvl moisture convergence on the nose
of a 50 knot LLJ trying to focus along I-29 by mid-morning. The
overnight hours are expected to remain dry but with a mixy wind,
temperatures may fail to fall below 50 degrees.
THURSDAY: Multiple hazards likely on Thursday. Early in the
morning, guidance shows a narrow tongue of low-mid lvl moisture
streaming up I-29. CAMS are a bit split in further development
of this moisture into a few showers/sprinkles but feel potential
is high enough to warrant slight chc PoPs into NW Iowa and SW
MN for a brief period of time. Meanwhile a surface front will
approach central SD by daybreak, gradually moving east through
the day. A channel of 50+ knots of low-lvl flow ahead of this
boundary will begin to mix downward quickly in the morning. Have
trended wind gusts towards the 90th percentile of the NBM which
aligned well with winds on Tuesday. Peak gusts may break the 45
mph mark at times into the afternoon. Surface based moisture
will be extremely limited ahead of this boundary, but another
wedge of elevated moisture may be enough to produce high based
sprinkles to showers as this front passes east into the
afternoon. Slight inhibition at 850 mb will likely prevent any
surface based convection from forming. The combination of strong
winds Thursday will also produce some patchy blowing dust and
minor air quality issues in the afternoon. For fire weather
concerns, please see separate discussion below.
THURSDAY NIGHT-FRIDAY NIGHT: The aforementioned boundary will be
east of the CWA by daybreak Friday, with winds switching to the
west northwest behind the boundary Thursday night. VERY dry air
will advect southeast behind this boundary, setting the stage
for RH values near 15% in the afternoon of Friday. Latest trends
have pushed the strongest wind potential along or north of
Highway 14 in the afternoon as high temperatures rise into the
80s. One thing to monitor for Friday evening will be the on/off
potential in guidance of some weak low-lvl convergence across
northern Nebraska and western Iowa in the evening. This area
will be on the edge of some slightly deeper moisture and MUCAPE
AOA 800-1000 J/KG. While its an intermittent signal in CAMs,
can't discount a thunderstorm or two trying to form south of
I-90 or towards Highway 20 if we somehow reach convective temps
in the low 90s.
SATURDAY: A brief rise in mid-lvl heights and influence of drier
Canadian airmass will prevent moisture and meaningful instability
from racing northward Saturday. For most of us, expect a dry and
rather nice Saturday as highs rise into the 80s.
SATURDAY NIGHT-MONDAY: Guidance is still quite uncertain, but trends
continue to shove a trough into the Plains Saturday night. The speed
at which low-lvl flow turns more meridional remains in question,
however both the GFS/ECMWF lift an elevated warm front
northward by Sunday morning. Convergence and upper dynamics
would support growing shower and thunderstorm risks moving
northward through the Tri-State area into Sunday morning. While
the severe weather risks overnight may be low, elevated parcels
might have upwards of 500-1000 J/KG supporting some hail growth
through mid-morning Sunday.
Even more uncertainty builds through the day on Sunday, focused on
the northward push of the warm sector into the Plains. GFS/EC/CMC
ensemble guidance all remains split 50/50 with the warm sector or
deeper instability either staying south of I-90, or on the flipside
spreading well north and bringing even moderate to strong
instability towards the Tri-State area by Sunday afternoon. AI based
models and CIPS analog guidance support the potential that does
exist for this event, further supporting early SPC day 4 outlooks.
Continue to monitor Sunday's forecast if you have outdoor events
planned, as this remains a very conditional severe weather forecast.
The upper trough deepens and pivots eastward into Monday, pushing a
surface front into the CWA overnight. Several waves of convection
could be possible into the morning hours of Monday, with stronger
convection potential focused east of I-29. A great deal of
uncertainty remains into Monday and it's certainly possible the
greatest potential of redevelopment along the front could be pushed
east of the CWA.
This entire system should bring meaningful rain to the CWA by time
it exits the region. NBM 10/90 percentile QPF over the 72 hour
period does range from a quarter inch to nearly 2", with a mean
around 0.75" in most locations. Of course convection can influence
these locations significantly, which is why the NBM probability of
>0.50" is only around 50% in any given location.
TUESDAY-WEDNESDAY: Drier weather and cooler conditions are expected
as we move into the middle of next week. High temperatures Tuesday
could struggle to climb through the 60s.
&&
.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1240 AM CDT Thu May 14 2026
VFR conditions are expected to prevail this period. Southeast winds
have begun to increase and will continue through the overnight and
into Today. By late morning widespread gusts of 35-40 kts are
expected with a few gusts of 47+ kts possible west of I-29. A brief
2-4 hour window of mainly directional LLWS is possible this morning
as the LLJ kicks in around midnight. Strong winds continue through
the afternoon, gradually tapering off from west to east in the
evening.
Mid to high level clouds filter in ahead of an approaching surface
front. A few isolated elevated showers and thunderstorms are
possible this morning. This afternoon a better chance for showers
and thunderstorms will form along and east of I-29. Confidence in
impacts to TAF sites is low, and so have left mention out at this
time.
&&
.FIRE WEATHER...
Issued at 343 AM CDT Thu May 14 2026
Red Flag Warning remains in effect today for areas east of US
Highway 281 from 10 AM to 7 PM CDT, where strong winds and very low
humidity will be coincident today. This combination will lead to
critical fire conditions. West of the James River Valley and into
the Missouri River Valley, strongest winds (this morning) continue
to be offset from the lowest humidity values (this afternoon), so
have kept that area out of the RFW. However, elevated to near
critical conditions are expected due to the low humidity and dry
fuels. Winds today will gust from 35-45 mph for most of the area,
with isolated stronger gusts around 50 mph. These higher gusts are
most likely between the James River Valley and I-29, as well as
across the higher elevations of the Buffalo Ridge and Coteau. RH
values improve through the evening, with winds tapering down from
west to east more quickly this evening and tonight.
Winds have trended downward slightly in the latest guidance compared
to 12 hours ago. Probability of gusts exceeding 35 mph have dropped
to less than 10% from the 20-40% along US Highway 14 for Friday
afternoon and evening. Given this, have left the Fire Weather Watch
as is. However, near critical to critical conditions are still
possible due to relative humidity values at or below 20% for the
entire area.
Elevated to near critical conditions continue Saturday due to the
very low humidity values. Again, relatively lighter winds may temper
widespread critical concerns, but near critical conditions are once
again possible.
Shower and thunderstorm chances return overnight Saturday into
Sunday and continue through early next week. Rainfall and higher
humidity should begin to reduce widespread fire concerns.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Red Flag Warning from 10 AM this morning to 7 PM CDT this
evening for SDZ039-040-054>056-060>062-065>071.
Fire Weather Watch from Friday morning through Friday evening
for SDZ038>040-052>056.
MN...Red Flag Warning from 10 AM this morning to 7 PM CDT this
evening for MNZ071-072-080-081-089-090-097-098.
Fire Weather Watch from Friday morning through Friday evening
for MNZ071-072-080-097.
IA...Red Flag Warning from 10 AM this morning to 7 PM CDT this
evening for IAZ001>003-012>014-020>022-031-032.
NE...Red Flag Warning from 10 AM this morning to 7 PM CDT this
evening for NEZ013-014.
&&
UPDATE...SG
DISCUSSION...Dux
AVIATION...AJP
FIRE WEATHER...SGHazardous Weather Outlook National Weather Service Sioux Falls SD 351 AM CDT Thu May 14 2026 IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097- 098-NEZ013-014-SDZ038>040-050-052>071-150900- 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- 351 AM CDT Thu May 14 2026 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. Near critical and critical fire conditions today due to very low humidity and wind gusts 35 to 45 mph. Isolated gusts to 50 mph are possible between the James River and Interstate 29. Use caution to prevent sparks. Blowing dust may lead to reduced visibility. Be prepared for changing visibility if traveling. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Elevated to near critical fire weather conditions continue Friday due to low humidity and wind gusts 20 to 30 mph. Showers and thunderstorms return Saturday night into Monday. Strong to severe storms are possible, although confidence is low in exact timing and coverage. Monitor the forecast especially if you have outdoor plans. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
4 high wind. Local standard time, as filed.
Sustained winds were between 40 and 49 mph at times, with gusts as high as 63 mph at a South Dakota Road Weather Information System site near Dixon.
Sustained winds were briefly between 40 and 48 mph, with gusts as high as 62 mph at a South Dakota Mesonet site 3 miles north-northwest of Academy and 61 mph at a South Dakota Road Weather Information System site at Platte-Winner Bridge.
Sustained winds were between 40 and 45 mph at times, with gusts as high as 59 mph at a South Dakota Road Weather Information System site near Tripp.
Sustained winds briefly reached 40 mph, with gusts as high as 58 mph at a South Dakota Road Weather Information System site near Dell Rapids.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2026Every state in 2026This day in weather historyWarnings in South Dakota, May 2026
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1343750, 1343848, 1343853, 1343874.