243
FXUS63 KFGF 190333
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1033 PM CDT Sat May 18 2024

.KEY MESSAGES...

- Potential for a few isolated strong to severe storms in south
central North Dakota Sunday afternoon.


&&

.UPDATE...
Issued at 1032 PM CDT Sat May 18 2024

Skies are clear and winds are diminishing quickly. This is all
within the forecast and no changes needed to sky grids and
updated wind grids for latest data.



UPDATE
Issued at 712 PM CDT Sat May 18 2024

Winds are diminishing and well below any advisory/warning
criteria. Winds will be under 10 mph after midnight. Skies are
mainly clear with disspating CU and will remain clear til late
tonight before high clouds move in from the west.

&&

.DISCUSSION...
Issued at 256 PM CDT Sat May 18 2024

...Synopsis...

While minor differences exist through the next 4-5 days ensembles
generally show our current zonal flow with upper troughing in the in
Alberta and Manitoba breaking down as the upper troughing digs south
with embedded shortwaves rotating out of strengthening southwest
flow aloft. This will result in a progressive surface pattern with
highs in the 60s to low 70s and thunderstorm chances through early
next week.

The vort max along the Canadian border will continue to produce
gusts of 60+ mph this afternoon with an NDAWN recently recording a 
wind gust to 60 mph as deep mixing and steep lapse rates to 3km have
been able to tap into 40+kt flow at 850mb. As the low tracks east
winds will subside especially with the loss of heating around 7-9pm.
Clear skies tonight on the back side of the low with SW flow aloft
bringing another shortwave into the area by Sunday afternoon. On
Some guidance shows a window for isolated strong or severe
thunderstorms (primary threat large hail) south of 1-94. BL Td`s
increasing and steepening mid lapse rates are shown to contribute to
instability in the 1000-1500 J/KG range while effective shear could
be in the 40-50kt range. Due to the high variation in surface
pattern (frontal zone may not set up this far northeast) and storm
coverage could remain more sparse. Worth monitoring though. could
see scattered areas receive over 0.25" with any storms that do
develop.

Continuing into Monday night/Tuesday another wave ejects east out
the upper trough and begins to deepen in the into a surface low in
South Dakota bringing warm air advection and possible fgen into
southeast North Dakota and west central Minnesota. Probs for over 1"
are around 30 percent in these areas. progressive rounds of showers
and storms will then continue through the week into next
weekend with zonal to southwest flow aloft and shortwave
activity persisting.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 712 PM CDT Sat May 18 2024

VFR thru thru the pd. Though shower and t-storm chances increase
in SE ND after 18z, but confidence in timing and coverage
forgoes mention in TAFs at this time. Winds diminshing and
turning southeast Sunday morning under 10 kts. Skies clear as
remaining CU dissipates. High and then mid clouds move in from
the west and south Sunday.

&&

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

&&

$$

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