Severe Thunderstorm Warning 71, NWS Grand Forks, ND

Area Forecast Discussion
National Weather Service Grand Forks ND
702 PM CDT Tue Jul 9 2024

.KEY MESSAGES...

- Isolated thunderstorms across the region through the evening.
  Severe storms are not expected.

- Risk for heat related impacts Friday through Sunday.

&&

.UPDATE...
Issued at 702 PM CDT Tue Jul 9 2024

Isolated showers and thunderstorms continue to form primarily
from the Red River Valley and points west. Most activity thus
far has been brief, with observations of heavy rain and gusty
winds approaching 50 mph. Look for this to diminish gradually
through the remainder of the evening as temperatures fall below
convective temps and cause low level lapse rates to fall.

&&

.DISCUSSION...
Issued at 256 PM CDT Tue Jul 9 2024

...Synopsis...

Ensemble guidance in decent agreement with evolution of the
larger scale pattern through the next week - depicting a
building western CONUS ridge with the main storm track across
Canada. The main uncertainty exists with the speed and track of
individual upper waves and how they will affect the ridging.
After surface ridging Wednesday into Thursday, there will be
periods of instability and forcing leading to thunderstorms, but
not sure how far south and/or severe risk (especially strength
of deep layer bulk shear). CWASP and CSU machine learning both
indicate periods of marginal severe risk this weekend into next
week.

...Isolated thunderstorms this evening...

Water vapor imagery indicates an upper wave approaching the
region from the north, with the cu field building across the
region. Radar imagery indicates showers/thunderstorms
developing. Deep layer shear is weak, so most storms will
effectively kill themselves. However, given steep lapse rates in
a decently mixed boundary layer, wouldn't be surprised to see
stronger storms produce gusts 40-50 mph. Additionally, stronger
storms may produce brief heavy downpours resulting in local
amounts around 1 inch and minor flood impacts in more
susceptible spots.

...Risk for heat related impacts this weekend...

As the upper ridge builds across the western CONUS and gradually
shifts east a much warmer and moist airmass propagates across
the region, especially Friday through Sunday. NBM MaxT 25-75
percentiles range from ~90F to ~98F during this period (across
the southern CWA at least), and with crops nearing peak
Evapotranspiration Td each day should be ~70F. Heat index values
would be >100F if the temperatures were able to reach upper 90s,
but that is still a low probability outcome. At this point most
likely (80% chance) heat index values each afternoon will be in
the mid to upper 90s, which is below advisory criteria. However,
the new NWS heat risk product (which accounts for duration of
heat including both daytime and nighttime temperatures as well
as if those temperatures pose an elevated risk of heat related
impacts based on data from the CDC) indicates a moderate risk
of heat related impacts Friday into Saturday with a major risk
of heat related impacts on Sunday.

www.wpc.ncep.noaa.gov/heatrisk

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 633 PM CDT Tue Jul 9 2024

VFR conditions prevail through the period at all TAF sites.
Isolated showers and thunderstorms remain possible through
around 03Z, which could include brief gusty winds. Otherwise,
winds remain light and variable through Wednesday morning, then
increase slightly, but generally remain less than 10 knots
heading into the midday hours.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

&&

UPDATE...Lynch
DISCUSSION...TG
AVIATION...Lynch

Hazardous Weather Outlook
National Weather Service Grand Forks ND
316 PM CDT Tue Jul 9 2024

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-102030-
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-Towner-Cavalier-
Pembina-Benson-Ramsey-Eastern Walsh-Eddy-Nelson-Grand Forks-
Griggs-Steele-Traill-Barnes-Cass-Ransom-Sargent-Richland-
Western Walsh-
316 PM CDT Tue Jul 9 2024

This hazardous weather outlook is for portions of eastern North
Dakota, west central and northwest Minnesota.

.DAY ONE...This Afternoon and Tonight

Isolated thunderstorms expected this afternoon and evening. The
main hazard will be lightning.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Risk for heat related impacts Friday through Sunday.

Friday...Strong Thunderstorm Risk.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated today.

Special Weather Statement
National Weather Service Grand Forks ND
334 PM CDT Tue Jul 9 2024

MNZ001>009-013>017-022>024-027>032-NDZ006>008-014>016-024-026>030-
038-039-049-052>054-100000-
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-Towner-Cavalier-Pembina-
Benson-Ramsey-Eastern Walsh-Eddy-Nelson-Grand Forks-Griggs-Steele-
Traill-Barnes-Cass-Ransom-Sargent-Richland-Western Walsh-
Including the cities of Crookston, East Grand Forks, Ada, Hadler,
Faith, Flaming, Syre, Twin Valley, Halstad, Moorhead, Hallock,
Karlstad, Lancaster, Casperson, Fox, Hayes Lake State Park,
Malung, Pencer, Roseau, Salol, Baudette, Radium, Warren, Englund,
Florian, Stephen, Argyle, Newfolden, Middle River, Espelie,
Gatzke, Grygla, Rosewood, Red Lake, Redby, Ponemah,
Dakota Junction, Thief River Falls, Red Lake Falls, Fosston,
Fertile, McIntosh, Erskine, Bagley, Clearbrook, Bemidji, Lavinia,
Rosby, Mahnomen, Naytahwaush, Waubun, Alida, Ebro, Lake Itasca,
Long Lost Lake, Lower Rice Lake, Roy Lake, Upper Rice Lake, Nary,
Emmaville, Hubbard, Park Rapids, Detroit Lakes, Shoreham,
Wolf Lake, Breckenridge, Lawndale, Fergus Falls, Perham,
New York Mills, Parkers Prairie, Henning, Battle Lake, Wadena,
Staples Airport, Menahga, Cando, Considine, Dresden, Langdon,
Maida, Mount Carmel, Vang, Akra, Backoo, Cavalier, Leroy,
Walhalla, Bowesmont, Drayton, Fort Totten, Maddock, Leeds,
Minnewaukan, Devils Lake, Grafton, Nash, Oakwood, Park River,
New Rockford, Lakota, Mcville, Aneta, Tolna, Grand Forks,
Cooperstown, Finley, Hope, Mayville, Hillsboro, Kelso, Hatton,
Portland, Roseville, Valley City, Fargo, Lisbon, Enderlin,
McLeod, Gwinner, Milnor, Forman, Rutland, Wahpeton, Adams,
Lankin, and Fairdale
334 PM CDT Tue Jul 9 2024

...FUNNEL CLOUDS POSSIBLE ACROSS THE REGION...

Isolated showers and thunderstorms have developed across region.
Conditions are favorable for funnel clouds with any shower that
develops. These types of funnel clouds are usually short lived and
weak, and usually will not touch the ground or cause damage.

Special Weather Statement
National Weather Service Grand Forks ND
701 PM CDT Tue Jul 9 2024

NDZ038-039-100030-
Barnes ND-Cass ND-
701 PM CDT Tue Jul 9 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN CASS AND
NORTHEASTERN BARNES COUNTIES THROUGH 730 PM CDT...

At 701 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles southwest of Page, or 19 miles northeast of Valley City, moving
south at 15 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Page, Oriska, and Ayr.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4716 9784 4719 9755 4697 9744 4693 9783
TIME...MOT...LOC 0001Z 343DEG 15KT 4711 9771

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Thomas/Lynch

Special Weather Statement
National Weather Service Grand Forks ND
715 PM CDT Tue Jul 9 2024

NDZ029-100045-
Steele ND-
715 PM CDT Tue Jul 9 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN STEELE COUNTY
THROUGH 745 PM CDT...

At 714 PM CDT, Doppler radar was tracking a strong thunderstorm over
Blabon, or 34 miles north of Valley City, moving south at 15 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Hope, Blabon, and Sherbrooke.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4746 9794 4749 9773 4730 9762 4726 9791
TIME...MOT...LOC 0014Z 341DEG 14KT 4741 9782

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Thomas/Lynch

Special Weather Statement
National Weather Service Grand Forks ND
731 PM CDT Tue Jul 9 2024

NDZ039-100100-
Cass ND-
731 PM CDT Tue Jul 9 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN CASS COUNTY THROUGH
800 PM CDT...

At 731 PM CDT, Doppler radar was tracking a strong thunderstorm over
Tower City, or 18 miles east of Valley City, moving south at 25 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Tower City, Buffalo, Chaffee, Embden, and Alice.

This includes Interstate 94 in North Dakota between mile markers 308
and 322.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4698 9768 4698 9771 4702 9771 4706 9752
      4678 9733 4673 9768
TIME...MOT...LOC 0031Z 342DEG 22KT 4694 9762

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Thomas/Lynch