830
ACUS48 KWNS 100858
SWOD48
SPC AC 100856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Mon Jun 10 2024

Valid 131200Z - 181200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
On Thursday, an upper-level trough is forecast to move into the
Great Lakes region, as a cold front advances southward across the
Central Plains and mid to upper Mississippi Valley. Moderate
instability is forecast south of the front by afternoon, where the
models suggest that scattered thunderstorm development will take
place. In addition, a mid-level jet is forecast to move eastward
across the north-central U.S. on Thursday. Moderate deep-layer shear
is forecast along the southern edge of this broad mid-level jet,
which should support a severe threat during the late afternoon and
early evening.

On Friday, an upper-level ridge is forecast to move across the
north-central U.S. Some models suggest that an axis of maximized
low-level moisture will setup beneath the ridge over the central
states. If this scenario pans out, then severe storms would be
possible Friday afternoon and evening across parts of the central
Plains. The presence of the ridge and the lack of large-scale ascent
casts doubt on any particular scenario.

On Saturday, a shortwave trough is forecast to move into the
southern High Plains, as the upper-level ridge moves into the upper
Mississippi Valley. In the wake of the ridge, a pocket of moderate
instability could be in place across the Dakotas and Minnesota, as
is suggested by the ECMWF. This area would be favored for severe
storm development. However, uncertainty is still substantial at this
range, especially due to significant spread among the model
solutions.

...Sunday/Day 7 and Monday/Day 8...
On Sunday and Monday, model forecasts suggest that a moist and
unstable airmass will be in place across much of the north-central
U.S., as multiple short troughs move northeastward through the
region. Scattered severe storms will be possible each day ahead of
these features in areas that destabilize the most, with the greatest
potential likely from Nebraska northward into the Dakotas. However,
model spread continues to be large late in the Day 4 to 8 period.
Once the model solutions become in better agreement, a 15 percent
contour may need to be added in parts of the north-central states
for either Sunday or Monday.

..Broyles.. 06/10/2024