652
FXUS63 KFGF 021159
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
659 AM CDT Wed Jul 2 2025

.KEY MESSAGES...

- Isolated thunderstorms possible southeast North Dakota into
  west central Minnesota late this afternoon. 1 out of 5 severe
  risk.

- Severe thunderstorms are possible on Friday, July 4th, along
  with the potential for heavy rain in some areas during the
  evening and overnight hours.

- Heat indices approach 100 in the Red River valley Friday
  afternoon.

&&

.UPDATE...
Issued at 655 AM CDT Wed Jul 2 2025

Mid level showers associated with 500 mb short wave extends from
Walhalla ND to Bemidji. Lightning is diminishing so just
showers. Back edge of the mid shower development band is
Walhalla ND at 1130z. This shower band will move southeast and
keep showers within a narrow band between Roseau and Thief River
Falls to Red Lake MN thru mid morning. Updated pops a bit for
this slightly longer time before it ends. No changes to
afternoon pops in SE ND or WC MN.


&&

.DISCUSSION...
Issued at 346 AM CDT Wed Jul 2 2025

...Synopsis...

Early July pattern with numerous short waves moving thru the
Canadian prairies and northern US and these combined with
instability will bring periodic chances for thunderstorms into
next week. The strongest signal for potential severe weather and
heavy rainfall is for Independence Day late afternoon and night.

...Isolated thunderstorms today...

500 mb wave that has been well advertised by models moving into
northwest MN at 08z. Area of convection with it, below severe
limits. Several weaker short waves upstream though into
Saskatchewan and seeing mid level CU and a few t-storms with
these as well. So will have mention of t-storms far NE ND into
NW MN thru mid morning, may need to extend thru noon. No severe
weather anticipated. This wave is pushing a weak wind shift
southward with a north wind 5-10 kts anticipated to push into
southeast ND and west central MN this aftn. Late aftn, sfc CAPE
over 2000 j/kg in SE ND and west central MN. Forcing is weak
with a wind shift boundary in place with light south wind south
of the front and light north wind north of it. Looks to be from
around Park Rapids to near Fargo. A few of the CAMs and the 06z
NAM 3km are indicating isolated convection forming along the
boundary 21z period and moving southeast. Most guidance due to
isolated coverage keep pops well blo 15 pct so coord with ABR
and MPX and hand drew in 20 pops for a few storms near this
boundary. Ended pops at 00z but may be needed to go a bit
longer. Bulk shear in the 25-35 kts may allow updrafts to grow
enough to support hail to 1 inch and also with high cloud bases
brief strong wind gusts psbl. Coverage is isolated.


Thursday will bring much more humid conditions as dew pts
increase to around 70 in SE ND and west central MN by late aftn.
Could be higher, those were NBM values. 850 mb/700 mb warm
advection Thu aftn and evening will send a warm 14C airmass at
700 mb into the area. Elevated convfection does look likely
western ND Thursday late day and evening. Signs point to a
complex of storms moving northeast into southern Manitoba from
northwest ND Thu night on west edge of 45 kt low level jet and
west edge of warm mid level airmass. SPC has day 2 marginal for
severe just west of the fcst area but something to watch as
wouldnt be suprised to see strong storms skirt our northwest
fcst area Thursday overnight.




...Friday severe threat and heavy rain potential...

What happens Thursday night will likely determine where any sfc
boundary will be located for Friday. Pops for Friday in the fcst
are likely too broad brushed, as all of Friday will not be
stormy. Best thoughts is that a surface bounday will be in
central ND midday and move east and lie from Cavalier to
Carrington around 21z and near Roseau-Grand Forks-Jamestown
00z Sat. Storms will fire along the boundary as along the
boundary 0-6 km bulk shear will be 30-35 kts and sfc
CAPE well over 2000 j/kg but CIN values will be several hundred.
So likely not breaking cap until right along boundary or just
west. Storms will move east thru the area Friday evening and
night. Heavy rain potential is high due to PWAT values of 2
inches. Severe storm threat depends on bulk shear and how strong
capping is in warm sector ahead of it. But could see a line of
storms move east associated with front with individual cells
training northeast along the boundary as it moves through.

- Heat on Friday...

High temps upper 80s to low 90s and dew pts in the 70 will bring
widespread heat index values of 93 to 98. Wet bubl globe temp in
the high to extreme category and heat risk at level 3.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 655 AM CDT Wed Jul 2 2025

Light winds today...under 10 kts anticipated in all areas. Wind
direction will be predominate north DVL, GFK, TVF and be south
then north later today BJI and FAR. Isold tstm chance Fargo area
late aftn, but otherwise a few showers around BJI and near TVF
thru 15z. Winds turning southeast by 12z Thu.

&&

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

&&

$$

UPDATE...Riddle
DISCUSSION...Riddle
AVIATION...Riddle