Flash Flood Warning 3, NWS Bismarck, ND

597 
WGUS73 KBIS 031429
FFSBIS

Flash Flood Statement
National Weather Service Bismarck ND
929 AM CDT Thu Sep 3 2026

NDC049-031530-
/O.CON.KBIS.FF.W.0003.000000T0000Z-260903T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
McHenry ND-
929 AM CDT Thu Sep 3 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 AM CDT THIS
MORNING FOR NORTHEASTERN MCHENRY COUNTY...

At 929 AM CDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 2 and 3 inches of rain have
fallen. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Towner and Denbigh.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4839 10062 4847 10049 4847 10028 4828 10033
      4819 10057 4830 10074

FLASH FLOOD...RADAR INDICATED

$$

Heinert

930 
WGUS73 KBIS 031456
FFSBIS

Flash Flood Statement
National Weather Service Bismarck ND
956 AM CDT Thu Sep 3 2026

NDC049-031506-
/O.CAN.KBIS.FF.W.0003.000000T0000Z-260903T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
McHenry ND-
956 AM CDT Thu Sep 3 2026

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN MCHENRY
COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.

&&

LAT...LON 4839 10062 4847 10049 4847 10028 4828 10033
      4819 10057 4830 10074

$$

Heinert

Area Forecast Discussion
National Weather Service Bismarck ND
719 AM CDT Thu Sep 3 2026

.KEY MESSAGES...

- Scattered showers and thunderstorms across northwest and
  central North Dakota this morning and afternoon. A few storms
  may be strong to severe, mainly in north central North
  Dakota.

- Critical fire weather conditions are possible in far
  southwest North Dakota on Friday.

- Temperatures warming to well above normal through Saturday,
  then cooling back to near or slightly below normal early to
  mid next week.

- Medium to high chances for showers and thunderstorms Sunday
  through Labor Day.

&&

.UPDATE...
Issued at 711 AM CDT Thu Sep 3 2026

Thunderstorms continue over portions of northwest and central
North Dakota this morning, with the strongest convection now
over north-central North Dakota where a recent report of ping
pong ball size hail was received. This is on the northern end
of a low-level jet with plenty of elevated instability in
place. Expect the severe threat with these storms to continue
through this morning, along with the potential for locally heavy
rainfall.

&&

.DISCUSSION...
Issued at 535 AM CDT Thu Sep 3 2026

The Northern Plains lie under southwest flow aloft early this
morning between a transient ridge exiting the Red River Valley
and a deep longwave trough over the Pacific Northwest. A nearly-
stacked low pressure system is depicted on water vapor imagery
spinning northward through southern Alberta, with a separate
surface low analyzed in southeast Montana. A broad expanse of
low level warm air advection and moisture transport downstream
of these features has ignited areas of showers and
thunderstorms. One cluster of widely scattered showers and
isolated thunderstorms has been migrating eastward across south
central North Dakota into the James River Valley. Meanwhile,
clusters of much stronger thunderstorms were moving through
northwest and north central parts of the state as of 5 AM CDT.
These strong to at times severe storms are moving through an
environment with up to 2000 J/kg MUCAPE and effective bulk shear
as high as 40-50 kts. Convective evolution through this
afternoon is uncertain, and CAMs offer little consistency in
potential outcomes. The ongoing convection may continue to lift
northeastward into southern Canada by this afternoon. Some CAMs
then hint at trailing redevelopment in north central North
Dakota this afternoon as an upper level jet streak lifts
northeast off the Rockies, but there are obvious questions on
how the environment may be modified by morning convection.
Model soundings and two-dimensional CIN fields suggest a
capping inversion is likely to keep storms elevated through the
day, but UH fields in the HREF broadly support strong to severe
convection in north central North Dakota this afternoon with a
similar CAPE/shear parameter space as mentioned above. Storm
mode could be mixed or clustered as there is no well-defined
surface boundary where convection is forecast, so will leave
our projected hazards at hail up to ping pong ball size and
winds up to 60 mph. Torrential rainfall could also caused
localized flooding, as has already been observed in Williston
and southwest Ward County early this morning.

Mid to upper level ridging is forecast to amplify over the
Northern Plains on Friday as a deep upper low spins over the
Pacific Northwest. This brings the high temperature forecast
into the 90s along and to the south and west of the Missouri
River, along with a strengthening southeast surface flow around
20 to 25 mph. In western North Dakota, RH is forecast to fall
below 30 percent south of the Missouri River, with minimum
values closer to 15 percent in the far southwest along the
Montana border. The greatest overlap in strong winds and low RH
is in Slope and Bowman Counties, where a Fire Weather Watch has
been issued for Friday afternoon and early evening. Surrounding
areas in west central and southwest North Dakota could see near-
critical fire weather conditions on Friday.

The ridge is forecast to become even more amplified on
Saturday, with forecast highs ranging from the mid and upper
80s north to lower and mid 90s south. The low level jet could
induce convection over parts of the region late Friday night
into Saturday morning, but mostly dry weather is otherwise
anticipated from tonight until Saturday night when the deep
western CONUS trough begins kicking shortwave energy into the
Northern Plains. This culminates in widespread low to medium
shower and thunderstorm chances Sunday through Labor Day as a
more potent shortwave lifts northeastward over the region while
the original Pacific Northwest low spins toward the Canadian
Rockies. Temperatures are favored to trend cooler early to mid
next week as the upper low crosses southern Canada.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 711 AM CDT Thu Sep 3 2026

Scattered showers and thunderstorms will continue over northwest
and central North Dakota this morning and afternoon. A few
stronger storms are possible, especially over north central into
parts of northwest North Dakota, with erratic gusty winds and
hail. Categorical flight restrictions to MVFR/IFR are possible
with any thunderstorm, mainly from visibility reductions caused
by heavy rainfall, but also possibly from lower ceilings.
Outside of showers and storms, areas of fog over parts of
southwest North Dakota will result in IFR to LIFR visibility
through mid-morning. At this time, it appears the reduced
visibility should remain south of the KDIK terminal.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Friday afternoon through Friday
evening for NDZ040-043.

&&

UPDATE...JJS
DISCUSSION...Hollan
AVIATION...JJS

Hazardous Weather Outlook
National Weather Service Bismarck ND
520 AM CDT Thu Sep 3 2026

NDZ040-043-041030-
Slope-Bowman-
420 AM MDT Thu Sep 3 2026

This Hazardous Weather Outlook is for portions of southwest North
Dakota.

.DAY ONE...Today and Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

A Fire Weather Watch is in effect on Friday. See
www.weather.gov/bis for additional information.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to provide reports to the NWS using standard
procedures, including through our social media accounts.

NDZ017-018-031>033-041-044-041030-
McKenzie-Dunn-Golden Valley-Billings-Stark-Hettinger-Adams-
520 AM CDT Thu Sep 3 2026 /420 AM MDT Thu Sep 3 2026/

This Hazardous Weather Outlook is for portions of northwest North
Dakota and southwest North Dakota.

.DAY ONE...Today and Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Near-critical fire weather conditions are possible on Friday.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to provide reports to the NWS using standard
procedures, including through our social media accounts.

NDZ001-009-010-019-020-035-036-042-046>048-050-051-057>062-041030-
Divide-Williams-Mountrail-Mercer-Oliver-Burleigh-Kidder-Grant-
Emmons-Logan-La Moure-McIntosh-Dickey-Western McLean-
Eastern McLean-Western Morton-Eastern Morton-Western Sioux-
Eastern Sioux-
520 AM CDT Thu Sep 3 2026 /420 AM MDT Thu Sep 3 2026/

This Hazardous Weather Outlook is for portions of northwest North
Dakota, south central North Dakota, and southeast North Dakota.

.DAY ONE...Today and Tonight

Isolated to scattered thunderstorms are possible this morning.
Widespread severe weather is not expected, but some storms could
be strong with hail up to the size of nickels.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to provide reports to the NWS using standard
procedures, including through our social media accounts.

NDZ002>005-012-013-022-023-025-037-055-056-041030-
Burke-Renville-Bottineau-Rolette-McHenry-Pierce-Sheridan-Wells-
Foster-Stutsman-Northwest Ward-
Central and Southern Ward/Minot Area-
520 AM CDT Thu Sep 3 2026

This Hazardous Weather Outlook is for portions of north central
North Dakota, northwest North Dakota, south central North Dakota,
and southeast North Dakota.

.DAY ONE...Today and Tonight

Isolated to scattered strong to severe thunderstorms are possible
this morning and afternoon. Expected hazards include hail as large
as ping pong balls and damaging winds up to 60 mph.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to provide reports to the NWS using standard
procedures, including through our social media accounts.

Hollan

Special Weather Statement
National Weather Service Bismarck ND
650 AM CDT Thu Sep 3 2026

NDZ012-056-031230-
Central and Southern Ward/Minot Area ND-McHenry ND-
650 AM CDT Thu Sep 3 2026

...A LINE OF STRONG THUNDERSTORMS WILL IMPACT CENTRAL MCHENRY AND
WARD COUNTIES UNTIL 730 AM CDT...

At 650 AM CDT, strong thunderstorms were located from 8 miles north
of Makoti to 7 miles southeast of Granville, or from 26 miles
southwest of Minot to 24 miles east of Minot, moving east at 30 mph.

HAZARD...Wind gusts up to 40 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
  Minot, Velva, Burlington, Surrey, Towner, Sawyer, Granville, Des
  Lacs, Makoti, Ryder, Denbigh, Karlsruhe, Rice Lake, Norwich,
  Berwick, Voltaire, Logan, Bergen, Simcoe, and George Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms and may lead
to flash flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4827 10192 4838 10106 4845 10028 4837 10028
      4837 10024 4805 10024 4788 10187 4802 10187
      4802 10192
TIME...MOT...LOC 1149Z 251DEG 26KT 4807 10178 4820 10134 4818 10077

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...40 MPH

Hollan

Preliminary Local Storm Report
National Weather Service Bismarck ND
707 AM CDT Thu Sep 3 2026

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

0700 AM     Hail             3 NNE Simcoe            48.20N 100.84W
09/03/2026  E1.50 Inch       McHenry            ND   Public

            Largest hail size reported.

&&

MH

Preliminary Local Storm Report
National Weather Service Bismarck ND
708 AM CDT Thu Sep 3 2026

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

0340 AM     Hail             Williston               48.15N 103.63W
09/03/2026  E1.00 Inch       Williams           ND   Trained Spotter

            Multiple reports of penny to quarter size
            hail.

&&

MH

Preliminary Local Storm Report
National Weather Service Bismarck ND
710 AM CDT Thu Sep 3 2026

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

0514 AM     Tstm Wnd Gst     8 SSW Sawyer            47.98N 101.09W
09/03/2026  M62 MPH          Ward               ND   Mesonet

            10 m wind gust at NDAWN station Sawyer 7 S.

&&

MH

Special Weather Statement
National Weather Service Bismarck ND
711 AM CDT Thu Sep 3 2026

NDZ040>044-061-031415-
Slope-Hettinger-Grant-Bowman-Adams-Western Sioux-
Including the cities of Marmarth, Mott, New England, Elgin,
Carson, New Leipzig, Bowman, Hettinger, and Porcupine
711 AM CDT Thu Sep 3 2026 /611 AM MDT Thu Sep 3 2026/

...PATCHY DENSE FOG ACROSS PORTIONS OF SOUTHWEST NORTH DAKOTA
EARLY THIS MORNING...

Patchy dense fog may reduce visibility to one quarter mile or less
for brief periods of time over parts of southwest North Dakota
early this morning. Motorists should be prepared for rapidly
changing visibility, and should use extra caution traveling. Be
extra cautious at intersections, school bus stops, and railroad
crossings.

The fog is still expected to dissipate by mid-morning.

Preliminary Local Storm Report
National Weather Service Bismarck ND
712 AM CDT Thu Sep 3 2026

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

0430 AM     Rain             Williston               48.16N 103.63W
09/03/2026  M1.63 Inch       Williams           ND   CO-OP Observer

&&

MH