805
FXUS63 KFGF 110910
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
410 AM CDT Thu Jul 11 2024

.KEY MESSAGES...

- Risk for heat related impacts Friday through Sunday,
  especially for heat sensitive or vulnerable groups and anyone
  without effective cooling or hydration.

- Medium chance for thunderstorms Friday night and Saturday
  night, some may be severe.

&&

.DISCUSSION...
Issued at 346 AM CDT Thu Jul 11 2024

...Synopsis...

Ensemble guidance in decent agreement with evolution of the
larger scale pattern into early next week - depicting a
building western CONUS ridge with the main storm track across
Canada. Ensemble members diverge with the speed and track of
individual upper waves and how they will affect the ridging.
Uncertainty increases with the large scale pattern into the
middle of next week as ensemble members diverge and many
potential outcomes exist.

Surface ridging into Friday will lead to mostly quiet weather
with minimal impacts over the next couple days.

...Heat Impacts...

Surface ridging and 500mb ridging over the Northern Plains will
allow us to stay fairly warm up until Sunday morning. NBM MaxT
25-75 percentiles range from ~85F to ~91F for today and reaching
up to 96F through Saturday in the southern river valley. 850mb
and 925mb temperatures are in the upper 20s (celsius) with a
deep mixing from relatively clear skies, temperatures were
increased to favor the 75th percentile. There is some smoke in
the upper levels that would dampen our ability to reach the 90th
percentile increasing temperatures into the mid 90s. The
apparent temperatures range from 85 to 101. 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 at least a moderate risk of
heat related impacts, which would be mainly for heat sensitive
or vulnerable groups and anyone without effective cooling or
hydration.

...Thunderstorms Friday night and Saturday night...

Convection this weekend would tend to limit overall heat
impacts, and the majority of ensemble membership produces
convection at some point. Of course, if capping holds (no
convection) heat impacts will be more severe. At this time most
likely outcome is for convection into the morning hours each
morning, which would limit the northern extend of the warmer
airmass. there is uncertainty with convective initiation this weekend.
There will be at least moderate instability each day, with weak
upper waves propagating across southern Canada. This could be a
"ridge rider" set up, with overnight convection as clusters of
storms move into the instability from the north. Deep layer
shear is weaker Friday night, but much stronger Saturday night.
Severe potential does exist, although at this point there are
still a lot of questions.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1115 PM CDT Wed Jul 10 2024

VFR conditions continue through the TAF period, with light and
variable winds overnight. Patchy fog will be possible within
northwestern Minnesota overnight through mid morning. Otherwise
post 15z we wil see winds turn toward the south with clear
skies. Hazy conditions are possible through the TAF period due
to high level smoke.

&&

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

&&

$$

DISCUSSION...MM
AVIATION...Spender