The summer of 2020 had more hot days than 2019, and July 17, 2020 was one of those hot days, with the exception of the Lake of the Woods region. Afternoon high temperatures ranged in the 80s to low 90s, with dew points in the mid 60s to mid 70s.
Every event with a place to put it. 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 FGF wrote it up.
The summer of 2020 had more hot days than 2019, and July 17, 2020 was one of those hot days, with the exception of the Lake of the Woods region. Afternoon high temperatures ranged in the 80s to low 90s, with dew points in the mid 60s to mid 70s. During the early afternoon, a line of thunderstorms over north central North Dakota moved into the Devils Lake region. By the early evening, showers and storms covered most of the area north of Interstate 94 in North Dakota, and highway 10 in Minnesota. By mid to late evening, these showers and storms continued to sag southward, covering the rest of eastern North Dakota and west central Minnesota. These storms produced large hail and damaging wind gusts. In addition, most areas received from 1 to 4 inches of rain.
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 Grand Forks, ND wrote its last area forecast discussion before the first event at Jul 17, 1:16 PM CST, 24 minutes earlier.
Area Forecast Discussion
National Weather Service Grand Forks ND
216 PM CDT Fri Jul 17 2020
.SHORT TERM...(This evening through Saturday night)
Issued at 216 PM CDT Fri Jul 17 2020
See mesoscale discussion issued at 1:43pm for latest thinking on
evolution of storms and main threats through ~5pm. As of 2:15pm,
it appears that large DCAPE combined with storms starting to
become more surface based has allowed for the significant wind
threat to increase rapidly. This area also favorable for a tornado
over the next couple hours given favorable low level shear
environment. Anticipate this activity to build southeast into
greatest instability with swaths of significant winds the main
threat (along with the threats of ~2 inches, brief tornado, and
localized flash flooding).
.LONG TERM...(Saturday through Friday)
Issued at 216 PM CDT Fri Jul 17 2020
For Saturday...winds become northwesterly behind the system bringing
in cooler and drier air to the region as surface high pressure
builds in and storms continue moving east.
The pattern through the rest of the period beginning on Sunday shows
the upper trof sagging to the south...which will help keep
temperatures a bit more seasonable through the middle of next week
when ridging returns and temperatures again gradually warm up.
Otherwise...a series of disturbances will propagate through the
flow...keeping chances for precipitation in the picture through the
end of the period.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1253 PM CDT Fri Jul 17 2020
Main aviation threat will be a line of thunderstorms expected to
move through the region from west to east. This line of
thunderstorms will likely contain very strong wind gusts.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Heat Advisory until 7 PM CDT this evening for NDZ038-039-049-052-
053.
MN...None.
SHORT TERM...TG
LONG TERM...BH
AVIATION...TGHazardous Weather Outlook National Weather Service Grand Forks ND 522 AM CDT Fri Jul 17 2020 MNZ001>009-013>017-022>024-027>032-040-NDZ008-016-027-029-030-039- 049-052-053-181030- West Polk-Norman-Clay-Kittson-Roseau-Lake Of The Woods- West Marshall-East Marshall-North Beltrami-Pennington-Red Lake- East Polk-North Clearwater-South Beltrami-Mahnomen- South Clearwater-Hubbard-West Becker-East Becker-Wilkin- West Otter Tail-East Otter Tail-Wadena-Grant-Pembina- Eastern Walsh-Grand Forks-Steele-Traill-Cass-Ransom-Sargent- Richland- 522 AM CDT Fri Jul 17 2020 This hazardous weather outlook is for portions of eastern North Dakota, west central and northwest Minnesota. .DAY ONE...Today and Tonight Numerous severe thunderstorms are likely today across the area, with large hail up to 2 inches, brief line-embedded tornadoes, and damaging wind gusts of 75 mph or greater. Significant wind damage is likely with todays strongest storms. Localized flash flooding is possible. Heat index values will reach or slightly exceed 100 degrees today in southeastern ND. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Periodic thunderstorm chances are expected through next Thursday. .SPOTTER INFORMATION STATEMENT... Spotter activation may be required. NDZ006-007-014-015-024-026-028-038-054-181030- Towner-Cavalier-Benson-Ramsey-Eddy-Nelson-Griggs-Barnes- Western Walsh- 522 AM CDT Fri Jul 17 2020 This hazardous weather outlook is for portions of eastern North Dakota. .DAY ONE...Today and Tonight Numerous severe thunderstorms are likely today across the area, with hail 2 inches or larger, tornadoes, and damaging wind gusts of 75 mph or greater. Significant wind damage is likely with today's strongest storms. Localized flash flooding is possible. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Periodic thunderstorm chances are expected through next Thursday. .SPOTTER INFORMATION STATEMENT... Spotter activation may be required.
The Minot AFB radar (KMBX), 176 km away, was scanning. The volume nearest the first event began at 19:41 UTC.
24 thunderstorm wind, 9 hail, 2 tornado, 1 funnel cloud. Local standard time, as filed.
Several 3 to 5 inch diameter branches were blown down in shelterbelts.
A brief tornado touchdown occurred in an open field just north of highway 2. The tornado continued to the east for less than a quarter of a mile. Peak winds were estimated at 70 mph. The tornado was wrapped in heavy rain and downburst wind, on the leading edge of a squall line.
Several large branches were blown down near the Frost Fire Resort.
Several 12 inch diameter branches were blown down in a shelterbelt. Dime to nickel sized hail also fell.
The wind gust was measured by a NDAWN mesonet sensor. A nearby north to south running irrigation system was flipped to the east.
A brief funnel cloud was spotted under a persistent wall cloud. A webcam caught the funnel cloud.
The wind gust was measured by a RWIS mesonet sensor along highway 2.
A tornado briefly touched down near highway 2, snapping trees in a shelterbelt. A nearby RWIS mesonet sensor reported a wind gust to 101 mph. The tornado was likely wrapped in heavy rain and downburst winds. Peak winds were estimated at 105 mph.
The wind gust was measured by a NDAWN mesonet sensor.
A secondary burst of winds struck a RWIS mesonet sensor along highway 2.
A few 3 to 5 inch diameter branches were blown down around town.
Metal roofing and siding were blown off a building.
Several large branches were blown down.
A tree was snapped in half.
The wind gust was measured by a RWIS mesonet sensor along highway 2.
The wind gusts were estimated.
Trees were blown down.
The wind gust was measured at the Grand Forks airport.
The wind gust was measured by a RWIS mesonet sensor.
Golfball to baseball sized hail fell.
A light pole and several large branches were blown down near the post office.
The hail fell near Woodland Resort.
Trees were blown down by a thunderstorm gust front.
A road sign was blown over.
Tree damage occurred throughout town.
Trees were blown down.
Large tree branches were blown down around town.
The wind gust was measured by a personal weather station.
Several trees were blown down in shelterbelts.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in North Dakota in 2020Every state in 2020This day in weather historyThe tornado archive for North Dakota, 2020Warnings in North Dakota, July 2020
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: 898192, 898193, 898194, 898195, 898196, 898197, 898198, 898199, 898200, 898201, 898202, 898203, 898204, 898205, 898206, 898207, 898208, 898209, 898210, 898211, 898212, 898213, 898214, 898215, 898216, 898217, 898218, 898219, 898222, 898223, 898224, 898225, 898226, 898227, 898228, 898229.