National Weather Service Raw Text Product

651 
FXUS63 KFGF 111156
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
656 AM CDT Wed Jun 11 2025

.KEY MESSAGES...

- Thunderstorm chances increase Sunday and Monday

&&

.UPDATE...
Issued at 653 AM CDT Wed Jun 11 2025

Nothing suprising going on as we past sunrise. Smoky, hazy sky.
Elevated showers continue to move east just south of the ND
border and just south of Grant county MN. Patchy ground fog
formed around 530 am and in a couple spots was thick, but
shallow via webcams. It will burn off fast, and coverage isnt
like it was Tues AM.  


&&

.DISCUSSION...
Issued at 329 AM CDT Wed Jun 11 2025

...Synopsis...

500 mb short wave is in northwest Ontario and this will move
east and high pressure will develop Thursday into the weekend
over northeast Manitoba. This will play a role in how north
precipitation does get winds at the surface turn northeast
Thursday into Friday and drier air at the surface from this high
will act to keep preciptation from spreading north. How strong
is this drier air and how far north does significant
precipitation get into the fcst area remains unclear.   

WNW flow at 500 mb over the area today and lasting into the
wekend. Flow may become a bit more southwest next week but
uncertainity with that as models and various ensembles have been
poor at forecasting when a ridge may build north into the
central or northern Plains. With this fast flow at 500 mb, it
it will be a parade of short waves through the area, with tracks
of them focusing on Wyoming, South Dakota into southern
Minnesota. One wave will move east today and give scattered
showers thru northern SD right up to the ND border. T-storm
chances will be more southeast SD, far southern MN, northern
Iowa closer to a frontal zone that will extend in that area and
where there will be highest instability....near 1000 j/kg Sfc 
based CAPE. There is a weak wave in southern Saskatchewan with a
few mid level showers on radar....and some short term models do
keep this moving east along the Intl border into far northeast
ND this aftn. It would appear though these showers will be from
mid cloud bases over 10k feet and thus chances of measurable
precip is blo 10 pct. 

Based on sfc smoke concentrations from the HRRR will have areas
of smoke most areas today into tonight...though some lowering of
sfc smoke concentrations does occur Thursday. Plus with rain
chances moving in elected not to have smoke with rain chances,
just picked the rain part as predominate weather type to work
with.

Speaking of Thursday...stronger 500 mb wave moves east thru SD.
850 mb low track has been variable with ECMWF holding a bit
farther south track closer to a surface front and sfc CAPE of
1000 to 1500 j/kg. GFS, NAM and Canadian are a bit farther north
with 850 mb low track more thru northern SD and has better
moisture advection into far SE ND into WC MN that does the
ECMWF. Even with the big farther north track...instability of
more than 500 j/kg still stays south of our forecast area, with
peak of 1000-1500 j/kg staying farther south. But this system
being stronger and able to bring up more moisture at 850 mb with
a 40 kt 850 mb jet ahead of 850 mb low, Rain will develop pretty
quickly into SE ND/WC MN by 18z Thu and peak in intensity mid
aftn into the evening Thursday. Embedded t-storms as well but no
severe weather is expected. How far north the rain gets remains
a bit more questionable...it will get at least to Highway 2 but
in a lighter fashion.  

...Thunderstorm chances increase Sunday into Monday...


This wave moves out Friday....then a relatively quiet period
Friday night/Saturday...before any potential system arrives from
the west Sunday afternoon or Monday. Models have been highly
variable with track, timing, strength of this next wave and how
much unstable air will be brought north. GEFS ensembles and NBM
have continued to indicate 70 pct of more than 1000 j/kg into
central and southeast ND Sun aftn into Sun night. Depending on
wave timng, it would look like the best chance for any organized
t-storms would be Sun night or Monday. Severe remains to be seen
as while we have more instability, with PWATs up to 1.5 inches
it would argue maybe more heavier rain potential vs severe. This
is the period we will continue to watch.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 653 AM CDT Wed Jun 11 2025

Light winds today, under 10 kts. Direction variable this morning
but predominate north to northeast turning east as we go thru
the afternoon into tonight. MVFR vsbys in smoke, haze at least
this morning. Sky cover wise, scattered cirrus and mid cloud
with increasing clouds tonight, but well into the VFR range for
cloud bases. 

&&

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

&&

$$

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