Special Weather Statement, NWS Grand Forks, ND

Area Forecast Discussion
National Weather Service Grand Forks ND
855 PM CDT Sat Jul 3 2021

.UPDATE...
Issued at 855 PM CDT Sat Jul 3 2021

Storms have really fallen apart in the past half hour, although
showers and weaker storms over the northern Red River Valley will
likely hold together in some regard overnight...spreading through
portions of northwest Minnesota. These should be fed by a 35 knot
850mb jet and the 700/500mb short wave/earlier MCV. At this point,
it is not looking likely that much will be south of Interstate 94.
Since the lingering storms will not be very strong, rainfall
amounts will decrease...more toward the quarter inch or less
totals.

UPDATE Issued at 627 PM CDT Sat Jul 3 2021

Seems like all the action has been around an old MCV just east to
northeast of Devils Lake. Storms have been forming, decaying, and
re-forming in that area. So far, because of the lack of 0-6km
shear, these storms have been sub-severe, producing localized
heavy rain, wind gusts to 45 mph, and some pea to nickel sized
hail. There is not really much of a low level jet tonight, so
although the storms may sustain themselves, severe weather looks
minimal.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 311 PM CDT Sat Jul 3 2021

Vort / MCV with t-storms continue to move northeast with re-
development on south side where moisture inflow is esp at 850 mb
with target being Devils Lake. Question is what occurs later on
this aftn and evening. Airmass is unstable mixed layer capes of
2000 j/kg in central ND but not all that impressive into the RRV.
Southern edge of vort max/500 mb trough should trigger some storms
late aftn/eve south of current cluster and move into the RRV this
evening, but coverage and intensity is highly uncertain. As been
the case all warm season, moisture at the sfc is lacking ahead of
the system with temps reaching the low 90s in the RRV and dew pts
mixing out into the low-mid 50s in a few areas, notably northern
RRV. Whereas dew pts farther west are in the mid 60s Jamestown to
Bismarck. So ingredients there for for strong to locally severe
storms into the evening but no real surface boundary present and
location is driven more by mid and upper level features. Will need
high cores of 50 dbz to get substantial hail. Tornado threat not
non-existent, but lack of any surface boundary or wind shift may
dampen threat despite mid/upper level circulation / MCV move into
NE ND.

Drier air moves in Sunday from the west with chance for
thunderstorm development in the afternoon regulated to far eastern
fcst area. Looks warm and muggy though until west-Northwest winds
take over mid to late aftn.

.LONG TERM...(Monday through Saturday)
Issued at 311 PM CDT Sat Jul 3 2021

SUMMARY...Primary story of the long term period will be the chance
for substantial rain on Monday night into Tuesday morning,
especially across the southern Red River Valley. As a prominent
shortwave trough brings attendant isentropic ascent within a moist
airmass, the potential for substantial rain over the south valley
seems solid. Later in the period, another chance for precipitation,
although predictability is low given ensemble spread. With ridging
giving way to troughing over the northern plains, temperatures will
be much more comfortable in the 70s and 80s all week.

MONDAY NIGHT THROUGH TUESDAY...A deepening shortwave trough is
expected to develop and deepen over the northern plains early next
week. With a combination of warm air advection within the lower
levels and cyclonic vorticity advection aloft, a broad region of
ascent is expected to provide rain chances Monday night through
Tuesday morning. With PWAT values increasing to above 1" and 1.5"
and deeper saturation (a far cry from what we've seen most of the
summer), the probability for substantial precipitation amounts seems
well within the range of outcomes. On top of this, isentropic ascent
within the 300-310K levels indicate the zone of maximized ascent
will likely be in the south valley. Ensemble member spread progs the
south valley with an IQR of 0.25-0.5" across the south valley,
although convective elements with elevated instability and the hint
at frontogenetic forcing potential will facilitate the potential for
isolated higher totals. On top of this, NBM probabilities for totals
greater than 0.25" are around 50%, mainly across the south valley
where ascent will be maximized. Across the entire area,
probabilities of 0.1" precipitation are at least 50%. Luckily, with
instability scoured from the area, severe weather does not appear
likely at this time. What appears to be the most likely outcome at
this time is widespread shower and a few thunderstorms, especially
across the south valley Monday night into Tuesday morning, providing
meaningful precipitation over much the area. Although most ensemble
members do place the axis of maximum ascent and precipitation within
the south valley, there are a few members that vary with the zone of
maximum precipitation, pushing it as far north as the central Red
River Valley. While not a likely outcome, it still sits within a
reasonable range of outcomes. Within the reasonable worst case
scenario would be isolated higher totals possibly exceeding an inch
over 24 hours, although the likelihood of this being a widespread
phenomenon isn't too high.

REST OF THE PERIOD...The rest of the period will primarily be
characterized by much cooler temperatures in the 70s and 80s.
Another wave will progress through the area late in the period,
although ensemble spread remains high so predictability is rather
low at this time.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 627 PM CDT Sat Jul 3 2021

Really unsure what to do with the storms in the next 0-6 hours, so
left them out of the TAFs. Will update when something becomes more
likely. Otherwise, outside of any thunderstorm activity, not
expecting any ceiling issues. The gusty south winds will decrease
overnight, then expect a slowly shifting west to northwest wind on
Sunday. The northwest winds will become gusty by Sunday afternoon.

&&

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

UPDATE...Godon
SHORT TERM...Riddle
LONG TERM...Perroux
AVIATION...Godon

Hazardous Weather Outlook
National Weather Service Grand Forks ND
538 AM CDT Sat Jul 3 2021

NDZ006>008-014>016-024-026>030-038-039-049-052-054-041045-
Towner-Cavalier-Pembina-Benson-Ramsey-Eastern Walsh-Eddy-Nelson-
Grand Forks-Griggs-Steele-Traill-Barnes-Cass-Ransom-Sargent-
Western Walsh-
538 AM CDT Sat Jul 3 2021

This hazardous weather outlook is for portions of eastern North
Dakota.

.DAY ONE...Today and Tonight

Near record highs are expected this afternoon. Strong to severe
thunderstorms will bring a risk of hail up to one inch and
damaging wind gusts up to 60 mph.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Near record highs Sunday could bring heat related impacts.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

MNZ001>009-013>017-022>024-027>032-040-NDZ053-041045-
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-Richland-
538 AM CDT Sat Jul 3 2021

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

.DAY ONE...Today and Tonight

Near record highs are expected this afternoon. Scattered
thunderstorms are expected during the evening and overnight hours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Near record highs Sunday could bring heat related impacts.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS ND
744 PM CDT SAT JUL 3 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0723 PM     TSTM WND GST     25 E NEW ROCKFORD       47.68N 98.60W
07/03/2021  M63 MPH          EDDY               ND   MESONET

            VIA MCHENRY NDAWN.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS ND
750 PM CDT SAT JUL 3 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0642 PM     TSTM WND GST     5 N ADAMS               48.49N 98.07W
07/03/2021  M62 MPH          WALSH              ND   MESONET

            10 METER GUST OF 62MPH. COURTESY OF NDAWN.

&&

Special Weather Statement
National Weather Service Grand Forks ND
826 PM CDT Sat Jul 3 2021

NDZ026>030-040230-
Griggs ND-Nelson ND-Steele ND-Traill ND-Grand Forks ND-
826 PM CDT Sat Jul 3 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN GRAND FORKS...
SOUTHEASTERN NELSON...NORTHWESTERN TRAILL...GRIGGS AND STEELE
COUNTIES UNTIL 930 PM CDT...

At 825 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from Logan Center to Sharon to near Glenfield.
Movement was east at 35 mph.

Half inch hail and wind gusts up to 50 mph will be possible with
these storms.

Strong thunderstorms will be near...
  Logan Center, Sharon and Finley around 830 PM CDT.
  Kempton around 840 PM CDT.
  Golden Lake, Northwood and Sutton around 845 PM CDT.
  Revere around 855 PM CDT.
  Hatton around 900 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Grand Forks.

&&

LAT...LON 4752 9850 4762 9796 4787 9787 4772 9698
      4742 9709 4726 9753 4725 9846 4725 9847
      4732 9847 4733 9850
TIME...MOT...LOC 0125Z 285DEG 29KT 4778 9781 4760 9787 4746 9863

JR

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS ND
831 PM CDT SAT JUL 3 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0803 PM     TSTM WND GST     5 WSW NORTHWOOD         47.71N 97.67W
07/03/2021  M61 MPH          GRAND FORKS        ND   MESONET

            61MPH GUST. REPORTED BY A PERSONAL WEATHER
            STATION.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS ND
834 PM CDT SAT JUL 3 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0803 PM     TSTM WND GST     6 SW LOGAN CENTER       47.74N 97.90W
07/03/2021  M61 MPH          NELSON             ND   MESONET

            61MPH WIND GUST REPORTED FROM A PWS.

&&

Special Weather Statement
National Weather Service Grand Forks ND
914 PM CDT Sat Jul 3 2021

NDZ026-027-029-040315-
Nelson ND-Steele ND-Grand Forks ND-
914 PM CDT Sat Jul 3 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN GRAND FORKS...
SOUTHEASTERN NELSON AND NORTHWESTERN STEELE COUNTIES UNTIL 1015 PM
CDT...

At 914 PM CDT, Doppler radar was tracking a strong thunderstorm near
McVille, or 40 miles southeast of Devils Lake, moving east at 25 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

This strong thunderstorm will be near...
  Kloten around 925 PM CDT.
  Aneta around 940 PM CDT.
  Logan Center around 950 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Grand Forks.

&&

LAT...LON 4791 9819 4785 9770 4759 9783 4764 9799
      4767 9799 4767 9807 4774 9828
TIME...MOT...LOC 0214Z 288DEG 20KT 4781 9813

VG