975
FXUS63 KBIS 261749
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1249 PM CDT Sun May 26 2024

.KEY MESSAGES...

- Showers become likely (~60-80 percent chance) over most
  locations from west to east today into this evening.
  Thunderstorms also possible, some of which may have small hail
  and gusty winds.

- Precipitation chances remain over much of the area Monday,
  with dry conditions Tuesday into early Wednesday.

- Precipitation chances return late Wednesday, continuing
  through the end of the work week.

&&

.UPDATE...
Issued at 1248 PM CDT Sun May 26 2024

Shower and thunderstorm activity slowly starting to increase,
and will continue to do so through this afternoon into this
evening. The threat for severe weather remains similar to the
previous update, and overall low. A few pulse like thunderstorms
could become strong at times, with small hail and gusty winds
the main threat. Current trend is areas with at least partial
clearing are seeing enough instability for this limited threat.
Overall will continue to monitor thunderstorm development with
limited updates needed at this time.

UPDATE
Issued at 1040 AM CDT Sun May 26 2024

Limited changes needed this morning. This morning`s CAMs showing
two distinct rounds of showers and thunderstorms today. The
first is occurring now with mainly showers in western and
central ND. As this pushes east, a secondary round of
thunderstorms looks to develop in western and central portions
and also push east. Overall coverage still looks scattered to
perhaps widespread and made some minor PoP changes based on the
morning CAM runs. An isolated strong storm is still possible
this afternoon. Surface based CAPE is adequate, although mix
layer cape is low to modest. Lapse rates in the mid levels are
also low to modest, bringing mainly skinny CAPE profiles. There
is some shear, but not abundant amounts. Thus the main threats
today look to be generally sub severe hail, with maybe an
isolated storm producing quarter sized hail. Inverted V
soundings and DCAPE near 500 J/KG could also bring some gusty
winds. Interestingly to note the 0 to 3 KM shear is around 20
knots which is on the modest end. Thus the stronger more
organized storms could produce some wind gusts of 50 to 60 MPH.
Overall anyone with outdoor plans today should keep an eye on
the latest forecast and thunderstorm trends. Remember, when
thunder roars go indoors.

UPDATE
Issued at 757 AM CDT Sun May 26 2024

Temperatures in the northeast have generally warmed into the
40s. Thus the Frost Advisory in these areas has been allowed to
expire at 8 AM CDT. Otherwise the forecast remains on track.

UPDATE
Issued at 639 AM CDT Sun May 26 2024

Rain showers continue to gradually move into and develop over
western portions of the area. Over the far north central,
temperatures in the mid 30s are occurring, so will leave the
frost advisory in place. Only minimal changes have been needed.

&&

.DISCUSSION...
Issued at 422 AM CDT Sun May 26 2024

Latest surface analysis places low along the Manitoba/Ontario
border, with high over the Central Rockies. Upper level analysis
shows low stacked over its respective surface feature, with
weak ridging near the west coast. A variety of short waves noted
in the flow upstream from our area, with the closest one now
pushing from western into central Montana. A few light showers
well ahead of the wave are starting to work their way through
western portions of North Dakota. Elsewhere over our area, frost
advisory still remains in effect over far north central North
Dakota where temperatures have dipped into the mid 30s per
latest Rolla observation. A few patches of fog have also
developed over various parts of the area as wind has gone light
to calm over most locations.

For today, aforementioned wave continues its approach and
deepens, with showers becoming more numerous from west to east
across the area today. Some thunderstorms are expected, with a
few possibly becoming strong with small hail/gusty winds with
marginal instability/deep layer shear. Wave continues to move
east tonight, with precipitation tapering off over the west,
possibly continuing through the night over parts of central
North Dakota/James River Valley.

On Monday, aforementioned upper low to the northeast opens up
and starts wrapping into the flow of another low closing off to
its east. As it drops south, it will bring additional chances
for showers and possibly a few thunderstorms to much of our
area.

Upper ridge passes over for Tuesday into early Wednesday,
bringing a period of dry conditions. Ridge pushes east late
Wednesday as an upper low passes over the Canadian Rockies
resulting in active southwesterly flow over our area. Shower and
thunderstorm chances increase substantially from west to east
overnight as the initial wave with the aforementioned system
passes through. Precipitation chances then continue near daily
through the end of the week as the upper low moves through the
central part of the Prairie Provinces, and various waves rotate
through our area.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1248 PM CDT Sun May 26 2024

Showers and thunderstorms through this evening could bring some
impacts to area TAF sites. Overall VFR conditions are expected
during this time period, although any shower/thunderstorm could
briefly produce MVFR to IFR conditions. Coverage today looks to
be isolated to scattered. Thus use VCTS and TEMPO groups for
precipitation mention. Tonight into Memorial Day morning, shower
and thunderstorms become more isolated. VFR conditions could
become MVFR with lower clouds expected to move into the area.
Light winds today will become northwest tonight and perhaps
breezy on Memorial Day.

&&

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

&&

$$

UPDATE...Anglin
DISCUSSION...JJS
AVIATION...Anglin