227
FXUS63 KBIS 201503
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1003 AM CDT Sat Jul 20 2024

.KEY MESSAGES...

- Isolated to scattered thunderstorms are expected today
  through Monday. The threat for severe weather remains low.

- Smoke aloft from distant wildfires will be found through the
  weekend (at least).

- High temperatures will mainly be in the 80s through Monday,
  while some 90s may return mid to late week.

&&

.UPDATE...
Issued at 1003 AM CDT Sat Jul 20 2024

It`s a quiet morning across the forecast area, with satellite
imagery and NDAWN photos showing thick smoke aloft over the
region. Main focus today will be isolated to scattered showers
and thunderstorms, although latest CAMs runs have held off on
developing any convection until a bit later in the day so we did
lower POPs for the next couple of hours. Otherwise going
forecast looks good.

UPDATE
Issued at 637 AM CDT Sat Jul 20 2024

Little needing updating this morning. Some patchy fog is being
reported, although coverage is not very widespread. Will
maintain patchy fog mention for the next couple of hours. Smoke
aloft will be hazy skies today. Isolated to scattered showers
and thunderstorms are also possible today. With a lack of shear,
the threat for severe weather is low.

&&

.DISCUSSION...
Issued at 437 AM CDT Sat Jul 20 2024

Upper level ridge to our west keeps unstable northerly flow
across the region this weekend. The result will be temperatures
in the 80s, with lows near 60 and isolated to scattered
thunderstorms each afternoon and evening. Today the better
instability looks to be across the north, central, and east.
Shear is lacking today, as well as a good forcing mechanism.
Thus thunderstorms today will generally be pulse type airmass
thunderstorms, and with little shear should remain below severe
criteria. Tonight these storms generally diminish or become very
isolated. Similar conditions will then be found for Sunday with
isolated to scattered airmass type thunderstorms in the
afternoon and evening, while little shear limits their
potential to be severe as well. The highest PoPs for Sunday
slightly shift to generally south of Highway 2, peaking south on
Interstate 94. Patchy fog this morning has been more isolated
then expected, although have kept in mention for much of the
CWA. Similar conditions will be found tonight, which could
result in more patchy fog. Given the isolated reports this
morning have left it out for now. HRRR Smoke continues to show
abundant vertically integrated smoke through the weekend, which
could bring hazy skies. The HRRR Smoke near surface has some
limited smoke mixing down, which could bring some minor
reductions to visibility although confidence was not high enough
to include in the forecast at this time. Will continue to
monitor trends with this smoke and place in the forecast as
needed.

Ridge continues to be to our west on Monday, lingering similar
temperatures and light winds. A backdoor cold front could enter
into ND from the east and may provide slightly better lift and
shear for thunderstorms. The stronger storms, if any, may still
be to the east of the CWA, while isolated to scattered storms
are still possible for western and central ND. The mentioned
ridge then looks to progress eastward Tuesday through Thursday.
This is pretty well agreed upon in the clusters, which brings a
dry and warming forecast. NBM forecasts are towards the higher
end of spreads, increasing confidence highs in the 90s could
return during this time period. A look at the NWS Heat Risk maps
does show perhaps some Moderate or higher heat related impacts
mid to late next week. Apparent temperatures right now are
forecast to be 90 to near 100 degrees, especially on Thursday.
This is a generally dry airmass though which could help limit
apparent temps. This dryer air could even bring afternoon RH
values between 20 to 40 percent mid to late next week. As the
ridge continues to push east later in the week the resultant
southwest flow aloft could bring the next chances for showers
and thunderstorms, while temperatures look to remain above
normal.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 637 AM CDT Sat Jul 20 2024

VFR conditions are generally expected through the forecast
period. Patchy fog remains possible this morning. Sites with
patchy fog could see MVFR to IFR conditions, although confidence
was not high enough to include in the TAFs at this time.
Another round of afternoon and evening showers and thunderstorms
are possible for today. Confidence was not high enough to place
in the TAFs, although most sites have a 20 to 40 percent chance
for thunderstorms. Wildfire smoke could be found aloft during
most of the forecast period, possibly mixing down to the surface
at times. A light northeast wind is expected during the day
today, becoming light and variable tonight. Patchy fog may also
return tonight into Sunday morning, although confidence was not
high enough to include in TAFs at this time.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...Jones
DISCUSSION...Anglin
AVIATION...Anglin