Alert archive / North Dakota / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 249, NWS Bismarck, ND

August 9, 2020McHenry County, Pierce County, North Dakota

NWS Bismarck, ND issued this severe thunderstorm warning at Aug 9, 2020, 5:47 AM CDT for McHenry County, Pierce County, North Dakota. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 9, 2020, 5:47 AM CDT (10:47 UTC)
Expired: Aug 9, 2020, 6:30 AM CDT
In force: 43 min
Issued by: NWS Bismarck, ND
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

Counties McHenry County, ND, Pierce County, ND

The radar

The Minot AFB radar (KMBX), 45 km from the middle of the area, began a volume at 10:52 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 10.8 hours before the alert went out and 166 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2499 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 187 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Bismarck, ND wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 9, 4:28 AM CDT, 1 hour 19 minutes earlier.

Area forecast discussion, Aug 9, 4:28 AM CDT, 1 hour 19 minutes before

Area Forecast Discussion
National Weather Service Bismarck ND
428 AM CDT Sun Aug 9 2020

.SHORT TERM...(Today and tonight)
Issued at 332 AM CDT Sun Aug 9 2020

Confidence in CAM models has increased as they have reasonably
depicted the convection across western and north central North
Dakota this morning.

This area is in a region of isentropic lift and associated
convergence of the low level jet, with convergence along an
eastward moving cold frontal boundary as well. Cape values of 1500
and shear of 35 kts would seem to support some marginally severe
thunderstorms. However, so far the storms have not been persistent
enough, showing severe characteristics for a volume scan or two
then falling apart. So there is some potential for large hail and
gusty winds this morning, but short lived pulse storms are
expected.

The thunderstorms will fairly quickly move east with the front
today, and by early afternoon thunderstorms will be exiting the
region across the southern James River Valley.

There the low level parcels will briefly see CAPE values exceed
4000 this afternoon (by 2 pm CDT) on the NAM forecast sounding.
but they may not have residency time in this rich airmass for very
long as the cold front sweeps through by 4 pm CDT. So we will
continue to message a marginally severe potential southeast today.

Tonight skies will clear as teh cold front moves east and high
pressure builds in.

With the surface high over the region with light winds blend gives
overnight lows from teh upper 40s to mid 50s.

.LONG TERM...(Monday through Saturday)
Issued at 332 AM CDT Sun Aug 9 2020

We will transition from cyclonic flow aloft Monday into more
zonal flow, then shortwave ridging by Tuesday. Height rises aloft
should suppress widespread convection Monday and Tuesday.

The next chance for more widespread thunderstorms will be
Wednesday into the weekend, as several upper lows migrate
through southern Canada. During this process, severe shortwaves
will move through the cyclonic flows aloft keeping the period
from Wednesday through Saturday active for thunderstorms. Active
buy not widespread would be more accurate.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1215 AM CDT Sun Aug 9 2020

VFR conditions are expected this forecast. At midnight CDT a cold
front extended across western North Dakota. The front will be the
focus for scattered thunderstorms as it moves east to Minnesota
Sunday evening.

&&

.FIRE WEATHER...
Issued at 332 AM CDT Sun Aug 9 2020

Elevated fire weather concerns will be seen for a number of days
through early next week.

A moderate westerly h500 flow across the Rockies will maintain
low dewpoints across the lee side of the mountains in Montana.
Todays cold frontal passage will be able to bring some of that
very dry air into western North Dakota. With dewpoints as low as
the mid 30s in the afternoon possible over western North Dakota
today and Monday.

Although temperatures will be cooler, the dry air will favor
minimum relative humidity around 20 percent today, and 15 to 20
percent Monday.

Today will see northwest winds of 15 to 20 mph across the west.
Monday the winds will be across the north.

Elevated fire weather conditions are expected today with minimum
RH around 20 percent with widespread winds of 20 mph across the
west.

Near critical fire weather conditions are possible Monday,
with min RH 15 to 20 percent. But the strongest winds on Monday
will be displaced to the north from the lower RH somewhat.

&&

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

SHORT TERM...WAA
LONG TERM...WAA
AVIATION...WAA
FIRE WEATHER...WAA

Hazardous weather outlook, Aug 9, 4:46 AM CDT, 1 hour 1 minute before

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In the hours before

Special weather statement, Aug 9, 1:12 AM CDT, 4 hours 35 minutes before

Special Weather Statement
National Weather Service Bismarck ND
112 AM CDT Sun Aug 9 2020

NDZ017-090645-
McKenzie ND-
112 AM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN MCKENZIE COUNTY
UNTIL 145 AM CDT...

At 112 AM CDT, strong thunderstorms were located along a line
extending from near Watford City to 7 miles northwest of Little
Missouri State Park. Movement was northeast at 30 mph.

Half inch hail and wind gusts to 40 mph will be possible with these
storms.

Locations impacted include...
Watford City and Johnsons Corner.

LAT...LON 4797 10325 4782 10266 4767 10282 4767 10303
      4775 10333
TIME...MOT...LOC 0612Z 212DEG 24KT 4778 10330 4765 10284

ABELING

Special weather statement, Aug 9, 1:57 AM CDT, 3 hours 50 minutes before

Special Weather Statement
National Weather Service Bismarck ND
157 AM CDT Sun Aug 9 2020

NDZ017-090730-
McKenzie ND-
157 AM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN MCKENZIE COUNTY
UNTIL 230 AM CDT...

At 157 AM CDT, a strong thunderstorm was located 15 miles west of 4
Bears Lodge, or 20 miles northeast of Watford City, moving northeast
at 30 mph.

Penny size hail and wind gusts to 40 mph will be possible with this
storm.

Locations impacted include...
Keene and Charlson.

LAT...LON 4813 10288 4808 10270 4796 10263 4783 10291
      4796 10307
TIME...MOT...LOC 0657Z 227DEG 24KT 4797 10290

ABELING

Special weather statement, Aug 9, 2:18 AM CDT, 3 hours 29 minutes before

Special Weather Statement
National Weather Service Bismarck ND
218 AM CDT Sun Aug 9 2020

NDZ010-021-090800-
Mountrail ND-McLean ND-
218 AM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN MCLEAN AND
SOUTHEASTERN MOUNTRAIL COUNTIES UNTIL 300 AM CDT...

At 218 AM CDT, a strong thunderstorm was located 9 miles south of New
Town, or 33 miles south of Stanley, moving northeast at 35 mph.

Nickel size hail and wind gusts to 40 mph will be possible with this
storm.

Locations impacted include...
New Town, Parshall, Plaza, Van Hook Park, Parshall Bay Recreation
Area and Pouch Point Recreation Area.

LAT...LON 4817 10193 4786 10190 4779 10229 4780 10235
      4777 10237 4776 10243 4789 10262 4822 10226
TIME...MOT...LOC 0718Z 231DEG 32KT 4784 10251

ABELING

Special weather statement, Aug 9, 3:00 AM CDT, 2 hours 47 minutes before

Special Weather Statement
National Weather Service Bismarck ND
300 AM CDT Sun Aug 9 2020

NDZ010-090830-
Mountrail ND-
300 AM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN MOUNTRAIL COUNTY
UNTIL 330 AM CDT...

At 300 AM CDT, a strong thunderstorm was located near Ross, or 11
miles west of Stanley, moving northeast at 30 mph.

Penny size hail and wind gusts to 40 mph will be possible with this
storm.

Locations impacted include...
Stanley and Ross.

LAT...LON 4816 10264 4830 10279 4852 10248 4829 10225
TIME...MOT...LOC 0800Z 235DEG 25KT 4828 10263

ABELING

Special weather statement, Aug 9, 3:19 AM CDT, 2 hours 28 minutes before

Special Weather Statement
National Weather Service Bismarck ND
319 AM CDT Sun Aug 9 2020

NDZ002-011-090900-
Ward ND-Burke ND-
319 AM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN WARD AND BURKE
COUNTIES UNTIL 400 AM CDT...

At 319 AM CDT, a strong thunderstorm was located 10 miles south of
Lignite, or 18 miles west of Bowbells, moving northeast at 50 mph.

Penny size hail and wind gusts to 55 mph will be possible with this
storm.

Locations impacted include...
Bowbells, Lignite, Flaxton, Niobe, Coteau and Northgate.

LAT...LON 4900 10202 4874 10203 4856 10262 4879 10287
      4900 10252
TIME...MOT...LOC 0819Z 241DEG 45KT 4874 10264

ABELING

Special weather statement, Aug 9, 5:13 AM CDT, 34 minutes before

Special Weather Statement
National Weather Service Bismarck ND
513 AM CDT Sun Aug 9 2020

NDZ012-013-091100-
McHenry ND-Pierce ND-
513 AM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR PIERCE AND CENTRAL MCHENRY
COUNTIES UNTIL 600 AM CDT...

At 513 AM CDT, a strong thunderstorm was located 5 miles north of
Karlsruhe, or 31 miles southwest of Rugby, moving northeast at 45
mph.

Nickel size hail and wind gusts to 40 mph will be possible with this
storm.

Locations impacted include...
Rugby, Towner, Drake, Granville, Denbigh, Karlsruhe, Balta, Barton,
Berwick, Balfour, Bergen, Silva, George Lake and Orrin.

LAT...LON 4854 10041 4855 10017 4844 9988 4796 9986
      4791 10064 4824 10094 4859 10041
TIME...MOT...LOC 1013Z 245DEG 37KT 4817 10061

ABELING

The office that day

Everything else NWS Bismarck, ND issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 8, 8:57 PM CDT	Special Weather Statement	BIS	Bowman	48 min
Aug 8, 9:04 PM CDT	Severe Thunderstorm Warning	BIS	Bowman	41 min
Aug 8, 9:41 PM CDT	Special Weather Statement	BIS	Slope	34 min
Aug 9, 12:33 AM CDT	Special Weather Statement	BIS	McKenzie	27 min
Aug 9, 12:35 AM CDT	Special Weather Statement	BIS	McKenzie	25 min
Aug 9, 1:12 AM CDT	Special Weather Statement	BIS	McKenzie	33 min
Aug 9, 1:57 AM CDT	Special Weather Statement	BIS	Mountrail	33 min
Aug 9, 2:18 AM CDT	Special Weather Statement	BIS	Mountrail	42 min
Aug 9, 2:33 AM CDT	Severe Thunderstorm Warning	BIS	Dunn, McLean, Mountrail	34 min
Aug 9, 3:00 AM CDT	Special Weather Statement	BIS	Mountrail	30 min
Aug 9, 3:19 AM CDT	Special Weather Statement	BIS	Burke	41 min
Aug 9, 5:13 AM CDT	Special Weather Statement	BIS	McHenry, Pierce	47 min
Aug 9, 6:18 AM CDT	Special Weather Statement	BIS	Rolette	42 min
Aug 9, 8:45 AM CDT	Special Weather Statement	BIS	Rolette	30 min
Aug 9, 2:08 PM CDT	Tornado Warning	BIS	LaMoure	37 min
Aug 9, 3:23 PM CDT	Special Weather Statement	BIS	LaMoure	37 min
Aug 9, 3:30 PM CDT	Severe Thunderstorm Warning	BIS	LaMoure	30 min
Aug 9, 3:50 PM CDT	Severe Thunderstorm Warning	BIS	Dickey	20 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 2020 Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.