377
FXUS63 KFGF 211527
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1027 AM CDT Fri Jun 21 2024

.KEY MESSAGES...

- Isolated strong to severe storms possible in Devils Lake
  region Saturday late afternoon.

- Potentially strong to severe storms on Monday afternoon.

&&

.UPDATE...
Issued at 1027 AM CDT Fri Jun 21 2024

Most of the FA is seeing filtered high clouds this morning,
with the exception of the far south, or along the Dakotas border
into adjacent areas of west central Minnesota. Down in that
area, there is some lower stratus and fog, although visibilities
don`t appear to be less than about 2 to 3 miles. Lowered the
forecast cloud amounts to match a little better to these current
conditions. Otherwise, not much precipitation is materializing
across the southern FA, so will go ahead and lower those chances
through the day as well. The latest CAMs are still showing some
shower (maybe thunder) development by later afternoon,
especially west of the Red River Valley. However, even this
seems pretty subtle (no real strong forcing), so confidence is
pretty low that too much shower activity will develop today.

UPDATE
Issued at 653 AM CDT Fri Jun 21 2024

Area of rain and thunderstorms stayed well south of our fcst
area overnight and back edge of the rain is roughly Long
Prairie MN to Redwood Falls MN. ABR radar shows a few very light
showers NW of Aberdeen in an area of lower clouds. Otherwise
dry and not seeing much of a chance for organized showers thru
early aftn in our south.

&&

.DISCUSSION...
Issued at 329 AM CDT Fri Jun 21 2024

...Synopsis...

The jet stream pattern into next week will feature a 500 mb
ridge spreading west-southwest over Texas from its position over
Kentucky currently. Expect several 500 mb short waves to move
through the southern Canadian prairies the next 5 days with each
one potentially bringing a period of strong or severe storms.

For today into tonight, the axis of strong storms and heavy
rainfall has remained well to our south in southeast SD and
moving into southern MN. Northern edge of showers with this
feature look to brush far southeast fcst area today. There is
an additional short wave over Wyoming generating a few storms in
SE Montana and NE Wyoming. This wave may bring a few scattered
storms into Devils Lake basin or parts of E ND late this
aftn/eve. Instability is weak with this so no impacts are
anticipated, other than lightning which would occur from any
thunderstorm. Heavy rainfall is no longer a threat over the
forecast area with rainfall forecasts thru the weekend under one
half inch, most under one quarter inch.

...Isolated strong to severe storms possible in Devils Lake
region Saturday late afternoon...

A separate 500 mb short wave will move from southern Alberta
into SW Manitoba by Saturday afternoon. The southern edge of
height falls and cooler air aloft with this feature will brush
north central ND 21z-00z and CAMS indicate development of a few
storms with this, with higher coverage farther north in western
Manitoba. Instability is present, with MU CAPES up to 1000 j/kg
21z-00z period in the area east of Minot to the Devils Lake
area.

...Potential for strong to severe storms Monday afternoon...

A stronger 500 mb short wave will move in a similar fashion from
southern Alberta into southwest Manitoba by Monday aftn. This
time though the rain and storms will not be present to our south
and thus better return flow with SE wind bringing up 60+ dew pts
into the high plains Sunday aftn/night. Monday will see upper
wave in Manitoba with an eastward progressing cold front that
will work into eastern ND 21z-00z time period. Dew pts progged
to be 65-70 and MU CAPE values potentially in the 3000-4000 j/kg
range due to forecast sfc temps in the 80s to around 90. Warmest
and most unstable airmass in SE ND. Capping issues with warming
850-700 mb layer do look to be present and may play a role in
potential for thunderstorm development. Bulk shear will be
sufficient with values 45-55 kts. Something to monitor the next
few days. Supercell composite values forecast from GFS would
support supercell discrete cells mid to late aftn that may turn
into a larger cluster in the evening.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 653 AM CDT Fri Jun 21 2024

VFR conditions for most of the day but will watch some MVFR cigs
that should creep north late today into tonight into SE ND/WC
MN.  Light winds today, under 10 kts from the ESE.

&&

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

&&

$$

UPDATE...Godon
DISCUSSION...Riddle
AVIATION...Riddle