LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Thu Jul 02 2026
Valid 021200Z - 031200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN PLAINS INTO THE UPPER MIDWEST...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THE NORTHERN
PLAINS INTO PARTS OF THE UPPER GREAT LAKES AND MIDWEST AND OVER THE
SOUTHERN APPALACHIANS...
...SUMMARY...
Strong to severe storms will be possible from the northern Plains
into the Midwest and Great Lakes regions, as well as across the
southern Appalachians on Thursday. Isolated strong to severe storms
may also occur in the Tennessee Valley, central High Plains, and
parts of the Northeast.
...Synopsis...
The upper level pattern across the US will be characterized by
troughing across the western US with a high amplitude ridge across
the eastern US. Between these features, several shortwave troughs
will rotate through the flow across the central/northern Plains into
the Midwest. A surface low will be located across eastern Montana
into the western Dakotas, with a surface boundary extending from the
northern Plains into the Upper Midwest.
...Northern High Plains into the Great Lakes and Midwest...
Early morning convection is likely across some portion of North
Dakota in association with a vort max moving out of Montana. The
evolution of this activity will likely have implications on the
exact placement of the surface boundary by this afternoon across the
Dakotas. Afternoon thunderstorm development is expected near the
surface low and in the vicinity of the surface boundary/residual
outflow across the Dakotas by the afternoon. Coverage should
increase as a shortwave moves out of Montana into the
afternoon/evening with increasing forcing for ascent. Across the
northern High Plains, strong daytime heating amid steep low to
mid-level lapse rates will support moderate to strong instability.
This in combination with deep-layer shear around 40-45 kts will
support initial supercells capable of large to very large hail and
damaging wind. Through time, boundary parallel shear and large dew
point spreads promoting outflow dominate storms will likely support
one or more clusters/bowing segments moving south and east with
time, resulting in an increase in the damaging wind threat and
potential for a few significant gust 75+ mph.
...Southern Appalachians into the Tennessee Valley...
A very moist and unstable air mass is expected to be in place across
the Southern Appalachians into the Tennessee Valley this afternoon.
Widely scattered thunderstorms are expected to develop across the
high terrain, with tendency to cluster along outflows. Consensus is
highest across the Appalachians into the Tennessee Valley for a more
focused corridor of damaging wind potential.
...Central High Plains...
Isolated thunderstorms are expected to develop within the lee trough
across the central High Plains this afternoon. Moderate instability
overlapping with around 25-30 kts of deep-layer shear will support
potential for a mix of supercells and multi-cell clusters. Steep
low- to mid-level lapse rates and large temperature/dew point
spreads will support potential for severe gusts. Initial supercells
will pose potential for large hail.
...Northeast...
Northeasterly flow within the northern periphery of the eastern
ridge will allow for thunderstorm activity to track southward out of
Quebec/Ontario across portions of the Northeast this afternoon. The
presence of moderate to strong instability and 30-40 kt
of deep-layer shear will be supportive of organized storm modes with
the predominant hazard being damaging winds. Higher wind
probabilities and a level 2/Slight Risk may be needed with
additional outlook updates if a more favorable corridor of wind
potential become clearer.
..Thornton/Chalmers.. 07/02/2026
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