Mandan, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

635
FXUS63 KBIS 280607
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
107 AM CDT Sat Jun 28 2025

.KEY MESSAGES...

- The threat for severe thunderstorms is winding down, but
  strong storms producing torrential rainfall will remain
  possible across south central and southeast North Dakota
  overnight.

- There is a low chance (10 to 20 percent) for isolated strong
  to severe storms across parts of south central and eastern
  North Dakota Saturday afternoon and evening.

- Daily high temperatures through next week are mostly expected
  to range from the mid 70s to upper 80s. Today and Saturday
  will be humid for central and eastern North Dakota.

&&

.UPDATE...
Issued at 102 AM CDT Sat Jun 28 2025

The threat for large hail, damaging winds, and especially tornadoes
is diminishing. The Tornado Watch has been allowed to expire. Some
storms will remain strong through the night though, and there is
some concern that storms regenerating along remnant outflow
boundaries and the increasing low level jet could produce excessive
rain and localized flash flooding. A couple of Flood Advisories have
been issued for the city of Jamestown and eastern Emmons County,
respectively.

UPDATE
Issued at 1130 PM CDT Fri Jun 27 2025

Quick update to cancel the Tornado Watch for Sioux, Grant,
Morton, Oliver, Sheridan, and Pierce Counties. Storms have moved
east out of the counties so they should be in the clear.

UPDATE
Issued at 1049 PM CDT Fri Jun 27 2025

Quick update to add LaMoure and Dickey Counties to Tornado Watch
468.

UPDATE
Issued at 1021 PM CDT Fri Jun 27 2025

Quick update to clear western portions of the Tornado Watch.
Tornado Watch remains ongoing for the south central and up into
portions of the Devils Lake Basin. Damaging supercells continue
to track across these areas with an uptick in tornado
potential. We have had reports of tornadoes in Emmons around the
Temvik area and just north of Bismarck and the environment
should remain favorable for the next couple hours or so.

UPDATE
Issued at 912 PM CDT Fri Jun 27 2025

Clusters of supercells continue across much of central North
Dakota late this evening. While many of these storms remain
severe, there has been a little bit of a downward trend over the
past hour or so, potentially due to some residual capping. That
being said, the environment is still conducive to significant
severe weather across central North Dakota and into the James
River Valley/Devils Lake Basin. Thus, the threat should
continue for the next few hours.

UPDATE
Issued at 634 PM CDT Fri Jun 27 2025

Deep convective initiation appears underway just east and south
of Minot, with another area just south of Beulah. Rapid
supercell development is expected with all hazards possible
initially before eventually growing upscale into one or two
linear complexes. While the primary threats appear to be hail to
the size of baseballs and damaging wind gusts to 70 mph, initial
storms may also pose a tornado threat if they can remain
discrete. If storms grow upscale later this evening, the hail
threat may diminish a little bit but the wind threat could
increase with some gusts up to 80 mph.

UPDATE
Issued at 524 PM CDT Fri Jun 27 2025

Quick update to issue Tornado Watch 468 for portions of western
North Dakota and all of central North Dakota.

&&

.DISCUSSION...
Issued at 213 PM CDT Fri Jun 27 2025

Currently, a weak pressure pattern is situated across western
and central North Dakota. Temperatures were mostly in the mid
70s to lower 80s with mostly in the 60s, except some mid 50s far
west. Dewpoints in the upper 60s to lower 70s were noted over
far south central into eastern ND. SOO noted the weak surface
flow and no real indication of a boundary. WV satellite imagery
does show a shortwave over northeast MT and moving into
northwest ND. As this approaches, we would expect the surface
pressure gradient to tighten a bit with a more defined surface
trough, with CI more imminent. The CAMs have been hinting at
the northwest into the north central being the area favored for
initial CI. Once we see this, the favored trend seems to be
storms tracking to the south and east along the moisture
gradient that extends into southeast ND. As mentioned earlier,
the orientation of the shear vectors to the surface boundary in
the north central suggest a possible mixed or messy mode. As you
go farther south into south central ND the more perpendicular
orientation of the shear vectors to a surface boundary suggests
supercells may be more probable, but the atmosphere is at least
initially more capped. Initial CI, no matter where, will have
the potential to be supercellular with very large hail and
possibly a tornado or two (due to the very steep lapse rates,
high instability and generally low LCL`s anywhere, except for
western ND). Very significant hail CAPE is situated across all
of central ND. Any storms that do develop would have the
potential for very large hail. HRRR soundings from various
points in central ND this morning showed a lot of large hail
analogs. The greater tornado threat does look to be more over
the south central portion of the state, with the RAP STP
maximized here, although the STP has stretched farther north
with more recent runs. Later in the period the potential for
activity to congeal into clusters or bowing segments is expected
to increase. If/when this occurs, the main hazard would shift
from large hail to damaging winds. A look at the latest HREF UH
paintballs certainly suggest a blend of short and long tracks.
Short tracks may be more favored in the north, with a blend of
long and short tracks favored central and longer tracks favored
south, if capping issues can be overcome.

We increased the hail threat to baseball sized hail and kept the
winds to 70 mph for now, and with the potential for a tornado
or two.

Saturday the greatest threat for severe storms pushes south and
east of the forecast area. The James river valley is currently
within the SPC Marginal Risk for severe storms (Level 1 of 5). A
lot of how things play out Saturday will depend how things
develop this evening and into the overnight hours, so will not
spend much time on the severe threat Saturday.

Sunday and into early next week, looks to bring a break in the
severe weather. Temperatures through the period look to remain
mainly in the mid 70s to mid 80s. Periodic thunderstorm chances
do look to increase again by mid to late week.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 102 AM CDT Sat Jun 28 2025

Strong to severe thunderstorms will remain possible across
parts of south central and southeast North Dakota through much
of the overnight hours. Strong wind gusts, torrential downpours
causing IFR to LIFR visibility restrictions, and small hail can
be expected with the strongest storms. Additional showers and
much weaker thunderstorms could develop across portions of
western and central North Dakota later tonight through Saturday,
but forecast confidence on timing, coverage, and location is
low. Western and northern North Dakota will see west to
northwest winds increase to 10-20 kts Saturday afternoon, with
lighter winds elsewhere. VFR conditions are likely to prevail
outside of thunderstorms.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...Hollan
DISCUSSION...TWH
AVIATION...Hollan