Severe Thunderstorm Warning 145, NWS Bismarck, ND

008 
WWUS53 KBIS 301559
SVSBIS

Severe Weather Statement
National Weather Service Bismarck ND
1059 AM CDT Mon Aug 30 2021

NDC065-301630-
/O.CON.KBIS.SV.W.0145.000000T0000Z-210830T1630Z/
Oliver ND-
1059 AM CDT Mon Aug 30 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 AM CDT
FOR WESTERN OLIVER COUNTY...

At 1058 AM CDT, a severe thunderstorm was located 9 miles west of
Hannover, or 10 miles southeast of Beulah, moving southeast at 10
mph.

HAZARD...Golf ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of
southwestern Oliver County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4715 10176 4723 10169 4720 10141 4704 10156
TIME...MOT...LOC 1558Z 295DEG 10KT 4715 10161 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

SCHILD

Area Forecast Discussion
National Weather Service Bismarck ND
909 AM CDT Mon Aug 30 2021

.UPDATE...
Issued at 853 AM CDT Mon Aug 30 2021

No major changes for this update. Only blended in latest
observations and made slight adjustments to sky cover based on
satellite trends. CAMs continue to indicate the potential for
thunderstorms initiating as early as late morning or early
afternoon. Still not entirely confident in this solution. However,
should anything develop that early, will likely be elevated in
nature initially.

UPDATE Issued at 617 AM CDT Mon Aug 30 2021

No major changes were needed for this update. Just blended in the
latest observations of the sensible weather fields into the going
forecast.

&&

.SHORT TERM...(Today and tonight)
Issued at 412 AM CDT Mon Aug 30 2021

The potential for severe thunderstorms this afternoon and evening
across the west central and southwest highlights the short term
forecast period.

Early this morning, nearly zonal flow was noted at the mid to
upper levels, with a hint of subtle ridging near the Montana
border. A weak shortwave was also noted on water vapor satellite
imagery embedded within the flow over central Montana. This wave
should be the trigger to initiate a few isolated thunderstorms
across western and central North Dakota this afternoon and
evening.

Warm air advection and moisture will be on the increase through
the day, leading to a slightly warmer day than yesterday with
highs in the mid 70s across the northeast to the mid 80s
southwest. Dewpoints across much of the central and south will
rise into the mid 50s to lower 60s (highest values southwest and
south central). These temperature/moisture profiles will lead to
plenty of destabilization across the west central and southwest
this afternoon, leading to MLCAPE values in the 1500 to 2500 J/kg
range. This area of enhanced buoyancy will be collocated with
deep layer shear values on the order of 35 to 45 knots, which
would certainly be sufficient for supercells. While the parameter
space will be favorable for very large hail up to two inches in
diameter and winds gusts to 70 mph, there remains a lack of an
obvious trigger. The one exception will be the aforementioned
weak wave that will move through aloft (bringing with it modest
height falls and cooler temperatures aloft, leading to steep mid
level lapse rates southwest).

Thus, the severe threat will be conditional based on initiation,
but it seems likely that at least a handful of storms will form.
Most CAMs have been consistent with initiating isolated storms
over the west and south central during the 20z to 22z time frame.
These initial supercells should stay fairly discrete given the
isolated nature of the convection, but the severe threat may last
into the evening as a modest low level jet kicks in and storms
try to grow upscale south central. Most of the activity should
slide off into north central South Dakota around and after 06z
Tuesday. Expect overnight lows in the 50s.

.LONG TERM...(Tuesday through Sunday)
Issued at 412 AM CDT Mon Aug 30 2021

An upper level ridge axis amplifies on Tuesday overhead as a
Pacific Northwest trough digs south and east. This will keep most
of the day dry on Tuesday with only a few clouds hovering around.
Tuesday afternoon will also feature a stiff breeze out of the
southeast with sustained winds up to 25 mph and gusts to 35 mph. A
shortwave will then eject from the western trough as ridging
moves east, skirting the northwest and north central overnight.
This will lead to chances of showers and storms mainly across the
north through Wednesday morning.

The stronger wave then comes through later on Wednesday, which
should bring widespread showers and thunderstorms to western and
central North Dakota. The forecast CAPE/shear overlap would favor
a chance for severe storms across most of the central and into
the Turtle Mountains and James River Valley. Specific details
regarding exact location and timing remain uncertain, but this is
a period we continue to watch closely.

A few more thunderstorms will be possible on Thursday as the base
of the trough moves overhead by the night time hours. While
buoyancy will be modest, shear will be strong so a few stronger
updrafts are not out of the question. Showers (and perhaps a
storm or two) embedded in cyclonic flow will then be possible
Friday through Saturday morning behind the trough.

Temperatures will remain around or slightly below normal for this
time of year through the extended.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 617 AM CDT Mon Aug 30 2021

VFR conditions are expected through the period. Isolated
thunderstorms are possible this afternoon and evening across
portions of the west and central. Across the southwest, a few
storms could become strong to severe with very large hail up to
two inches in diameter and wind gusts to 70 mph. Due to the
isolated nature of these storms and uncertainty regarding exact
location and timing, have kept mention of any kind of
precipitation out of the TAF forecast for now.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

UPDATE...Telken
SHORT TERM...ZH
LONG TERM...ZH
AVIATION...ZH

Hazardous Weather Outlook
National Weather Service Bismarck ND
842 AM CDT Mon Aug 30 2021

NDZ001>005-009-025-037-311345-
Divide-Burke-Renville-Bottineau-Rolette-Williams-Foster-Stutsman-
842 AM CDT Mon Aug 30 2021

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

.DAY ONE...Today and Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

There is a chance of thunderstorms on Wednesday afternoon and
evening across much of western and central North Dakota. A few of
these storms could become strong to severe.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

NDZ017>021-031>035-040>046-311345-
McKenzie-Dunn-Mercer-Oliver-McLean-Golden Valley-Billings-Stark-
Morton-Burleigh-Slope-Hettinger-Grant-Bowman-Adams-Sioux-Emmons-
842 AM CDT Mon Aug 30 2021 /742 AM MDT Mon Aug 30 2021/

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

.DAY ONE...Today and Tonight

There is a slight chance for thunderstorms this afternoon and
evening. A storm or two could become severe. The main threats
would be hail to two inches in diameter and wind gusts to 70 mph.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

There is a chance of thunderstorms on Wednesday afternoon and
evening across much of western and central North Dakota. A few of
these storms could become strong to severe.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

NDZ010>013-022-023-036-047-048-050-051-311345-
Mountrail-Ward-McHenry-Pierce-Sheridan-Wells-Kidder-Logan-
La Moure-McIntosh-Dickey-
842 AM CDT Mon Aug 30 2021

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

There is a slight chance for thunderstorms this afternoon and
evening. While severe weather is not anticipated, a few storms
could become strong with small hail and gusty winds.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

There is a chance of thunderstorms on Wednesday afternoon and
evening across much of western and central North Dakota. A few of
these storms could become strong to severe.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

Telken

Special Weather Statement
National Weather Service Bismarck ND
1051 AM CDT Mon Aug 30 2021

NDZ020-301615-
Oliver ND-
1051 AM CDT Mon Aug 30 2021

...A strong thunderstorm will impact portions of southwestern Oliver
County through 1115 AM CDT...

At 1050 AM CDT, Doppler radar was tracking a strong thunderstorm 9
miles southeast of Beulah, moving southeast at 15 mph.

HAZARD...Nickel size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

This storm will remain over mainly rural areas of western Oliver
County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4713 10177 4724 10169 4719 10139 4700 10157
TIME...MOT...LOC 1550Z 296DEG 12KT 4715 10165

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...<30 MPH

SCHILD