O Brien, Minnesota Weather Forecast Discussion

298
FXUS63 KFGF 261918
AFDFGF
Area Forecast Discussion
National Weather Service Grand Forks ND
218 PM CDT Fri Sep 26 2025
.KEY MESSAGES...
- Chance of thunderstorms along the international border this
  evening.
- Fire weather potential increases through next week.
&&
.DISCUSSION...
Issued at 202 PM CDT Fri Sep 26 2025
...Synopsis...
Surface analysis this afternoon shows a cold front stretching
from Willow City down through west of Bismarck, progressing
eastward this afternoon. As this front progresses eastward,
forcing may be enough to generate showers and a few
thunderstorms this evening and overnight, particularly closer to
the international border. Instability is largely boundary-layer
based so organized convection is unlikely to develop.
Additionally, mid-level moisture content is very poor so it is
more likely than not we will see virga instead of showers and
thunderstorms. Regardless, impacts will be fairly minor and
mainly tied to lightning along the international border.
Large scale ridging will linger through next week, giving above
normal temperatures and increasing risk for fire weather
conditions to develop.
...FIRE WEATHER POTENTIAL...
With the aforementioned above normal temperatures through next
week combined with elevated flow aloft, the potential for fire
weather to become more of an impact is increasing. While it is
still early in the season, indicated by high HRB, ERC values are
beginning to rise but remaining mostly below the 60th
percentile. Dry weather will continue to linger for the period
with wetting rain very unlikely, so expect multiple days of low
relative humidity in the 20s and 30s through mid-week.
Generally, the bulk of ensemble guidance has the reasonable
worst case scenario for relative humidity in the mid-20s,
particularly Saturday and Sunday at this time (although this
could extend through next week as higher resolution CAMs start
entering the NBM). Expect at least mid 30s to develop with some
spots getting into the mid 20s this weekend.
While the signal for lower relative humidity is strong, there
isn`t a particularly strong signal for wind speeds to reach
critical criteria at this time. For this reason, the probability
for red flag conditions to develop is very low.
&&
.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1221 PM CDT Fri Sep 26 2025
VFR conditions will prevail for the TAF period. A front will
push eastward later this afternoon shifting winds from
southeasterly to westerly/northwesterly. Gusts between 20-25
knots are possible behind this front. Showers and a few
thunderstorms may accompany this front, but the bulk of this
activity should remain well north of any TAF site. For this
reason, no PROB30 group was used for it. Low level wind shear
may develop overnight tonight around BJI as the front continues
to push eastward. This will improve after sunrise tomorrow
giving way to little impacts to aviation.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
DISCUSSION...Perroux
AVIATION...Perroux

NWS FGF Office Area Forecast Discussion