SPC Aug 5, 2020 Day 4-8 Severe Weather Outlook

Day 4-8 Outlook

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0403 AM CDT Wed Aug 05 2020

Valid 081200Z - 131200Z

...DISCUSSION...
...Northern Plains to Upper Midwest Vicinity...

Strong ridging will persist across the southern/central tier of the
U.S. for much of the Day 4-8 period, maintaining seasonally hot
conditions with low severe potential. However, northern stream flow
will remain active near the U.S./Canadian border as a series of
shortwave trough migrate across the Canadian Prairie provinces,
resulting in enhanced mid/upper westerly flow. Seasonally moist
conditions will persist across the north-central U.S. and multiple
episodes of strong to severe thunderstorms will be possible From the
Dakotas/Nebraska eastward to the Upper Midwest, mainly Day 4/Sat
through at least Day 6/Mon. 

On Day 4/Sat, a cold front sagging northeast to southwest from
western MN into northern NE will modify as strong warm advection
spreads northward across the central Plains ahead of a shortwave
impulse. Storms are expected to develop in upslope southeasterly low
level flow in the vicinity of this boundary across western SD/NE
during the afternoon or early evening. As a low level jet increases
during the evening/overnight, upward development into an eastward
propagating MCS appears possible, and damaging winds are possible
across parts of SD/NE. 

By early-to-middle of next week, a stronger/deeper trough is
forecast to shift eastward across the region, and a stronger surface
cold front may eventually drop southward across much of the Plains
and portions of the Midwest, bringing more settled conditions
by/just after the end of the forecast period. While the overall
pattern appears favorable for multiple days of active convection
across the northern Plains/Upper Midwest vicinity Day 5/Sun through
at least Day 6/Mon, where exactly convection will develop each day
is uncertain and will be driven by prior days storms and mesoscale
processes/features that are not well resolved at longer time-scales.
Severe probabilities will likely be needed in subsequent outlooks
and trends will be monitored.

Read more

from SPC Forecast Products http://www.spc.noaa.gov/products/exper/day4-8/