SPC Aug 15, 2026 1630 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1630Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1135 AM CDT Sat Aug 15 2026

Valid 151630Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FRONT
RANGE/CENTRAL HIGH PLAINS AND MIDDLE OHIO VALLEY...

...SUMMARY...
Thunderstorms with severe wind gusts and isolated large hail are
possible from late afternoon into the evening across the central
High Plains. Severe wind gusts may also occur this afternoon through
early evening across parts of the Ohio Valley and Southeast.

...Front Range/Central High Plains...
Modestly strong southwesterly flow aloft coupled with strong
daytime heating, low-level upslope flow, and orographic lift will
support another day of thunderstorms regionally. These thunderstorms
should gradually move off the higher terrain into the central High
Plains later this afternoon, where a moderately
buoyant airmass will be in place. Around 30-35 kt of effective
bulk shear is expected over the region, which will support a mixed
mode with supercells and multicell line segments. Isolated large
hail is possible with any supercells, while severe wind gusts will
be possible with both supercells and line segments. The severe
threat should persist into the evening as this complex of storms
moves eastward through the central High Plains including
west/southwest Kansas.

...Midwest/Middle Ohio Valley...
Thunderstorms have generally weakened since the overnight, although
scattered showers/some thunderstorms and plentiful cloud cover
continue in areas progressively north of the Ohio River. An MCV is
readily apparent in observational data as it continues to move into
northwest Indiana, with an enhanced belt (40+ kt) of westerly winds
associated with the MCV per regional WSR-88D VWP data.

As clouds thin/abate, a gradual increase in renewed thunderstorm
coverage and intensity is expected later this afternoon. Mid-level
lapse rates will be poor, but dewpoints in the 70s F will support
moderate buoyancy, particularly in areas where cloud cover does not
overly inhibit diurnal heating, which will tend to generally be
southward toward the Ohio River. Strong updrafts and high
precipitable water will support the potential for wet microbursts
capable of producing damaging gusts, and some enhancement to the
low-level winds could also yield a brief tornado.

...Central Appalachians/Carolinas/Georgia...
A very moist airmass, characterized by dewpoints in the low to mid
70s, is in place regionally. Strong heating will destabilize the
airmass by the early afternoon, resulting in a large reservoir of
moderate buoyancy. Thunderstorm development is anticipated within
this destabilized airmass across the higher terrain of the central
Appalachians as well as any area of low-level convergence across the
remainder of the region. Vertical shear will be weak, and limited
storm organization is anticipated. Even so, the moderate buoyancy
could still support updrafts/downdrafts strong enough to produce
occasional damaging gusts.

...Central Plains/Mid Missouri Valley to Mid Mississippi Valley...
Elevated thunderstorms are expected again tonight, initiated by both
an approaching cold front and warm-air advection. Ample low-level
moisture and moderate buoyancy will be in place, but vertical shear
will be marginal. Isolated strong to severe storms are expected, but
a predominantly elevated and clustered storm mode should limit the
overall severe potential.

..Guyer/Chalmers.. 08/15/2026


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TV26mq

SPC Aug 15, 2026 1300 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1300Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0749 AM CDT Sat Aug 15 2026

Valid 151300Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE CENTRAL HIGH PLAINS AS WELL AS THE MIDDLE OHIO VALLEY...

...SUMMARY...
Thunderstorms with severe wind gusts and isolated large hail will be
possible from late afternoon into the evening across the central
High Plains. Severe wind gusts will also be possible this afternoon
into the early evening across parts of the Ohio Valley.

...Central High Plains...
Relatively moist southwesterly flow aloft coupled with strong
daytime heating and lift both from orographic effects and a weak
vorticity maximum will support another day of thunderstorms across
the central Rockies. These thunderstorms should gradually move off
the higher terrain into the central High Plains, where a moderately
buoyant airmass will be in place. Around 30 to 35 kt of effective
bulk shear is expected over the region as well, which is strong
enough to support a mixed mode with supercells and multicell line
segments. Isolated large hail is possible with any supercells, while
severe wind gusts will be possible with both supercells and line
segments. The severe threat should persist into the early to mid
evening as this complex of storms moves eastward through the central
High Plains.

...Central OH Valley...
An expansive, slow-moving MCS, characterized by widespread showers
and sub-severe thunderstorms, is centered over central IL this
morning. This MCS has been supported overnight by a southwesterly
low-level jet that extends from the southern High Plains into the
Mid MS Valley. This low-level jet is forecast to wane throughout the
morning, with a subsequent decrease in coverage and intensity of the
showers and thunderstorms within the MCS. Even so, the vorticity
maximum associated with this system will gradually drift eastward,
likely supporting renewed thunderstorm development across the
middle/upper OH Valley as it interacts with a diurnally
destabilizing airmass. Lapse rates will be poor, but dewpoints in
the 70s will still support moderate buoyancy, particularly in areas
where cloud cover does not overly inhibit diurnal heating. This
currently appears most likely from far southeast IN into southern OH
and northern KY. Strong updrafts and high precipitable water will
support the potential for wet microbursts capable of producing
damaging gusts.

...Central Appalachians into the Carolinas and GA...
A very moist airmass, characterized by dewpoints in the low to mid
70s, is in place from the GA and Carolinas into the central
Appalachians. Strong heating is forecast to destabilize this airmass
by the early afternoon, resulting in a large reservoir of moderate
buoyancy. Thunderstorm development is anticipated within this
destabilized airmass across the higher terrain of the central
Appalachians as well as any area of low-level convergence across the
remainder of the region. Vertical shear will be weak, and limited
storm organization is anticipated. Even so, the moderate buoyancy
could still support updrafts/downdrafts strong enough to produce
occasional damaging gusts.

...Central Plains/Mid MO Valley into the Mid MS Valley...
Elevated thunderstorms are expected again this evening through
tonight, initiated by both an approaching cold front and warm-air
advection. Ample low-level moisture and moderate buoyancy will be in
place, but vertical shear will be marginal. Isolated strong to
severe storms are expected, but a predominantly elevated and
clustered storm mode should limit the overall severe potential.

..Mosier/Dean.. 08/15/2026


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TV1xhL

SPC Aug 15, 2026 0600 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Sat Aug 15 2026

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
OHIO VALLEY SOUTHEASTWARD INTO THE CAROLINAS...AND IN THE CENTRAL
HIGH PLAINS...

...SUMMARY...
Thunderstorms with severe wind gusts and isolated large hail will be
possible from late afternoon into the evening across the central
High Plains. Severe wind gusts will also be possible this afternoon
into the early evening from parts of the Ohio Valley southeastward
into the Carolinas.

...Mid Mississippi and Ohio Valleys/Central
Appalachians/Carolinas...
At mid-levels today, a broad anticyclonic flow pattern will be in
place over the eastern U.S. Within the flow, a shortwave trough will
move eastward into the lower Ohio Valley. Ahead of this feature, a
moist and unstable airmass will be located from the mid Mississippi
Valley east-southeastward into the Ohio Valley and southern
Appalachians. In the morning, a convective complex is forecast to
move eastward into the southern Great Lakes, and will likely be
associated with a potential for severe wind gusts. To the south of
this complex, a quasi-stationary front and moist axis will be
located from the lower Ohio Valley southeastward into the southern
Appalachians, along which moderate instability will develop by
afternoon. Low-level convergence near the front will be the focus
for convective development. A new complex of surface-based
thunderstorms appears likely to form near the front and move
east-southeastward from western Ohio into the Virginias during the
afternoon. Additional storms will develop along and near the
instability axis over the western Carolinas due to topographical
forcing.

Model forecasts in the moist air suggest that MLCAPE will peak in
the 2000 to 3000 J/kg range in most areas. Near the instability
axis, precipitable water values in the 1.8 to 2 inch range and
moderate deep-layer shear will likely support a threat for severe
wet downbursts. This threat should persist into the early evening
with any line segments that become sustained over the higher terrain
of the southern and central Appalachians.

...Central Plains...
West-southwesterly mid-level flow will be in place over the
southwestern and central U.S. today. At the surface, a moist airmass
will be located from the foothills of the Rockies eastward into the
central Plains. By afternoon, moderate instability will develop over
much of the region. Scattered thunderstorms will form in the higher
terrain and move eastward into the lower elevations during the mid
to late afternoon. Some RAP forecast soundings at 21Z from eastern
Colorado northward into western Nebraska have 0-6 km shear near 35
knots with steep low to mid-level lapse rates exceeding 7 C/km. This
environment will support a mixed mode with supercells and multicell
line segments possible. Supercells should be capable of isolated
large hail, while severe wind gusts will be possible with supercells
and organized multicells. The severe threat should persist into the
early to mid evening as a complex of storms moves eastward through
the central High Plains.

..Broyles/Lyons.. 08/15/2026


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TV1mD6

SPC Aug 14, 2026 2000 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 2000Z Day 1 Outlook


Day 1 Convective Outlook AMEND 1
NWS Storm Prediction Center Norman OK
0532 PM CDT Fri Aug 14 2026

Valid 142000Z - 151200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
MIDWEST AND SOUTHEAST VIRGINIA...

AMENDED FOR INCREASED SEVERE PROBABILITIES IN SOUTHEAST VIRGINIA

...SUMMARY...
Severe thunderstorms remain possible this afternoon and evening
across parts of the mid Missouri and mid Mississippi Valleys, as
well as southeast Virginia. Isolated severe wind gusts may also
still occur in parts of the central Plains and from the Ohio Valley
to the Mid-Atlantic, as well as parts of the Northeast and
Southwest.

...Southeast Virginia...
Supercells which have developed across parts of southeast VA appear
to be anchored to a surface boundary, and they should continue to
pose some threat for large hail this evening as they track
southeastward. Although low-level flow remains modest, locally
greater effective SRH is present near this boundary, and a brief
tornado appears possible. Otherwise, scattered damaging winds may
also occur across parts of southeast VA with a loosely organized
cluster moving east-southeastward over the next few hours. See
Mesoscale Discussion 1982 for more details on the near-term severe
threat across this region.

..Gleason/Squitieri.. 08/14/2026

.PREV DISCUSSION... /ISSUED 1143 AM CDT Fri Aug 14 2026/

...Mid Missouri and mid Mississippi Valleys...
Thunderstorms have largely weakened through the early morning across
the middle Missouri Valley, with more of a lingering persistence
across Illinois/Indiana. Scattered showers remain rather common,
however, regionally with semi-prevalent cloud cover. Multiple MCVs
persist regionally at midday, including across central Iowa, and
more prominently near the Nebraska/Iowa border. Regional WSR-88D
data from Omaha/Des Moines/Davenport continue to sample enhanced
westerlies (35-50 kt) between 4-8 km AGL in association with these
MCVs.

Primary severe risk across this region today will be linked to the
amount of air mass recovery and associated destabilization that
occurs along the southern periphery of the residual convection and
ahead of the aforementioned slow-moving MCVs. Ample low-level
moisture is in place, and differential heating between the residual
cloud debris may yield an effective warm-front-like zone across
southern Iowa or near the Iowa/Missouri border. The airmass along
and south of this is forecast to destabilize and become moderately
to strongly unstable by the late afternoon. This should result in
renewed thunderstorm development by late afternoon into evening,
with sufficient deep-layer shear to support organized updrafts and
potentially some initial supercells. Modestly enhanced low-level
winds/SRH could yield a tornado risk. Strong wind gusts will
otherwise be possible with water-loaded downdrafts, as well as with
any bowing segments through this evening.

...Ohio Valley/Central Appalachians/Mid-Atlantic...
Outflows/differential heating across the lower Ohio Valley will
influenced thunderstorm redevelopment this afternoon, while storms
are starting to develop/increase across the Appalachians vicinity.
Vertical shear will generally be weak, but strong updrafts and ample
moisture will yield the potential for wet microbursts regionally.

...Central High Plains...
A shortwave trough currently moving through the Lower Colorado River
Valley is forecast to continue northeastward through the Four
Corners. Ascent associated with this wave will combine with
orographic lift in the foothills of the Rockies to support scattered
convective initiation by early afternoon. Thunderstorms will then
move northeastward into the moderately buoyant airmass over the
central High Plains. Deep-layer shear will be modest but sufficient
for a few organized updrafts capable of hail and damaging gusts.

...Northeast States...
Influenced by strong northwesterly flow aloft, a few stronger to
locally severe relatively low-topped storms may occur this afternoon
across northern/upstate New York into southern New England, with
strong/gusty winds as the primary hazard as convection progresses
southeastward.

...Lower Colorado River ...
With a moist air mass across the region, strong heating will support
afternoon airmass destabilization, yielding moderate buoyancy this
afternoon. Slightly stronger mid-level flow is anticipated over the
southern Nevada vicinity, supporting the potential for isolated
strong wind gusts.


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TV1dT2