Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Sat Jul 04 2026
Valid 041200Z - 051200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE
MID-ATLANTIC...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE CENTRAL/SOUTHERN PLAINS...
...SUMMARY...
Clusters of storms will move across parts of the Allegheny Plateau
into Mid Atlantic, with potential for widespread damaging wind.
Additional thunderstorms are expected across the Great Plains
Saturday afternoon and evening, posing a risk for damaging wind
gusts. Large hail is also possible across the Great Plains.
...Synopsis...
Height rises will continue across the western US, with more zonal
flow across the central US and upper-level troughing across the
Northeast and Quebec/Ontario. A modest belt of westerly flow around
30-40 kts will move through the trough in the
Northeast/Mid-Atlantic. A compact shortwave trough with enhanced
westerly flow will move through the flow across the Central Plains.
...Eastern Ohio Valley into the Mid-Atlantic...
Activity will likely be ongoing across some portion of northern PA
into northern NJ this morning. This will likely contribute to
lingering cloud cover and more muted daytime heating/recovery with
northern extent. South of the morning precipitation, strong daytime
heating and warming is expected, with temperatures climbing into the
90s to 100s F. A plume of steep mid-level lapse rates is already in
place across the region from WV into VA/MD/NJ. With daytime heating,
low-level lapse rates are expected to increase with moderate to
strong instability by the afternoon. Deep layer shear profiles will
be generally weak, with better shear to the north. Nonetheless,
several thunderstorm clusters are expected to develop across the
Blue Ridge Mountains/Shenandoah Valley moving north and eastward
though the afternoon. These will have the potential to produce
widespread damaging wind, especially if clusters can grow upscale
and develop strong cold pools.
Additional clusters are likely in the wake of morning convection
further north. Instability will be less, but sufficient deep layer
shear may support one or more clusters capable of damaging wind.
...Central/Southern Plains...
Evolution of thunderstorms across the central/southern Plains will
be dependent on evolution of morning convection across northern
Kansas. One or more MCVs may develop and drift south and eastward,
which will have impacts on the exact region that thunderstorms
redevelop by the afternoon. Guidance suggests that the corridor of
highest probability of development will be across southern Kansas
into northern Oklahoma. Within this region, widely scattered
thunderstorm activity is expected to develop by the afternoon, with
initial supercells capable of large to very large hail and perhaps a
tornado. These will eventually cluster and grow upscale, with a
likely MCS moving south into Oklahoma by the evening and an increase
in damaging wind potential.
More isolated supercell development is expected from the OK/TX
Panhandles northward into eastern CO/western KS/western NE. Deeply
mixed profiles and sufficient deep layer shear should support
potential for both large hail and damaging wind.
...Midwest into the lower Missouri Valley and western/central Ohio
Valley...
There is less confidence in evolution of afternoon thunderstorms
into the Missouri Valley and western/central Ohio Valley. Moderate
to strong instability will be in place with generally weak flow/deep
layer shear. Guidance suggests that several clusters of
thunderstorms may develop and spread eastward with damaging
wind/downburst potential. This will likely be focused in more
mesoscale corridors where residual outflow resides.
..Thornton/Moore.. 07/04/2026
Read more
SPC Forecast Products·