Mesoscale Discussion 1977
NWS Storm Prediction Center Norman OK
0121 PM CDT Fri Aug 14 2026

Areas affected...portions of the central Appalachians into the NC/VA
Piedmont

Concerning...Severe potential...Watch unlikely 

Valid 141821Z - 142015Z

Probability of Watch Issuance...20 percent

SUMMARY...A locally greater risk for damaging wind gusts may develop
across across portions of the NC/VA Piedmont downstream of
developing thunderstorms.

DISCUSSION...Latest surface analysis depicts a quasi-stationary/weak
cold frontal boundary extending roughly west-to-east from southern
DelMarVa into central Virginia and the central Appalachians. South
of this boundary, continued insolation and dewpoints in the low 70s
F should support 1500-2500+ J/kg MLCAPE by peak heating this
afternoon, sufficient for a few stronger updrafts. Effective shear
remains generally weak roughly south of the NC/VA border (less than
20 kts), which will favor an outflow-dominant/pulse-severe type
storm mode. Steepening low-level lapse rates and high PW (2+ inches
per the 12 UTC GSO observed sounding) will support an isolated risk
for wet microbursts and damaging wind gusts. Farther north, latest
objective analysis suggests that effective shear is locally enhanced
along the aforementioned surface boundary (20-30+ kts) across
central/southern Virginia. This could allow for a locally greater
risk for damaging wind gusts to materialize should a loosely
organized cluster evolve east-southeastward out of West Virginia
(where a recent report of thunderstorm wind damage is noted).
Regardless, the overall severe risk is expected to remain relatively
isolated and limited in magnitude. Thus, watch issuance appears
unlikely at this time.

..Chalmers/Guyer.. 08/14/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...AKQ...LWX...RAH...RNK...RLX...GSP...MRX...JKL...

LAT...LON   38468151 38508091 38468024 38347955 38047878 37717810
            37497779 37217765 36767760 36447773 36167794 35837832
            35647870 35517940 35518003 35678064 36008128 36868218
            37458257 38098261 38358228 38468151 

MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1143 AM CDT Fri Aug 14 2026

Valid 141630Z - 151200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
MIDWEST...

...SUMMARY...
Severe thunderstorms will be possible this afternoon and evening
across parts of the middle Missouri and middle Mississippi Valleys.
Isolated severe wind gusts will also be possible in parts of the
central Plains and from the Ohio Valley to the Mid-Atlantic, as well
as parts of the Northeast and Southwest.

...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.

..Guyer/Chalmers.. 08/14/2026

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1225 PM CDT Fri Aug 14 2026

Valid 151200Z - 161200Z

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

...SUMMARY...
Strong to severe storms are possible on Saturday from the central
High Plains eastward into parts of the Midwest, Ohio Valley,
southern/central Appalachians, and Carolinas.

...Synopsis...
The upper ridge is expected to broaden and expand westward on
Saturday. Modest to regionally moderate flow aloft will be confined
to the northern half of the CONUS. A convectively modified surface
boundary from the Mid-Atlantic westward into the Midwest and central
Plains will be the general focus for convection outside of MCV
features moving around the upper ridge.

...Midwest/Ohio Valley...
An MCV is forecast to be in northern Illinois/southern Wisconsin
Saturday morning. This feature will track eastward during the day.
Scattered storms are expected near the MCV and along a surface
boundary from the southern Great Lakes region into the central
Appalachians. Early morning precipitation and cloud cover associated
with the MCV is may limit surface heating, but the very moist
airmass will not need much heating to destabilize. Damaging winds
will be the main threat with a tornado or two possible, particularly
near the MCV. Storms may only be organized for short periods given
weak lapse rates and shear concentrated in the lower half of the
troposphere.

...Central High Plains into the Missouri Valley...
Another MCV is expected to track eastward through the central Plains
into Iowa/Missouri. Given the impacts of the preceding MCV on
Friday, it is not clear how much destabilization, and therefore
storm coverage will occur. Should afternoon storms develop, the
strongest activity will likely be on the southern flank of the MCV
from northeast Kansas into northern Missouri. Later in the evening,
additional storms are possible along the cold front.

Farther west, flow aloft in the central Rockies will become more
westerly. At the surface, continued moist upslope flow will promote
scattered to numerous storms by afternoon. Cloud cover may keep
temperatures somewhat cool, but steep lapse rates aloft and around
35-40 kt of effective shear near the terrain will support transient
supercell structures capable of large hail and severe wind gusts.
Storm/outflow interaction is likely with a few clusters propagating
eastward with time.

...Southern Appalachians into the Piedmont...
Strong heating of at least low 70s F dewpoints will promote strong
instability by the afternoon. Flow aloft will be weak to modest from
the northwest. Though storms may not be very organized, scattered
convection within the terrain may move east/southeast with time. One
or more clusters may develop leading to localized corridors of wind
damage potential.

...Central/Northern Minnesota...
A cold front will be the focus for potential isolated storm
development. Mid-level forcing for ascent will be quite weak and
thermodynamic profiles will be marginal. Should storms develop,
isolated strong outflow winds would be possible. Severe potential
remains too limited for probabilities.

...Northeast Oregon into central Idaho...
With a subtle shortwave trough moving through during the afternoon,
thunderstorms are likely to develop within the Blue Mountains and
move northeastward. Modest buoyancy and effective shear will promote
a couple of stronger storms. Small hail and gusty outflow winds may
occur, but severe potential appears limited.

..Wendt.. 08/14/2026

Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1146 AM CDT Fri Aug 14 2026

Valid 141700Z - 151200Z

A small contraction of the existing isolated dry thunderstorm
highlights was made across the Cascades as latest short term model
guidance shows thunderstorm development most likely along the
Cascade Crest into central OR. A slight northeastward expansion of
elevated highlights was made across the Southern Plains given recent
fire activity and latest forecast guidance trends. Continued breezy
south/southwest winds of 15-20 mph and low relative humidity this
afternoon will promote an elevated fire weather threat within an
anomalously dry fuelscape across portions of northwest TX, western
OK and far southern KS. Please see previous discussion for
additional details.

..Williams.. 08/14/2026

.PREV DISCUSSION... /ISSUED 0151 AM CDT Fri Aug 14 2026/

...Synopsis...
An expansive upper ridge is forecast to intensify over the central
US today. Troughing will remain along the periphery over the West
Coast. This troughing, along with monsoon moisture, should bring
another round of isolated dry thunderstorms to parts of the
Northwest. Meanwhile beneath the ridge, very hot temperatures, low
humidity and breezy winds will foster elevated fire-weather
potential across the southern Plains.

...Western WA/OR into northern CA...
Isolated dry thunderstorm are possible for portions of northwestern
CA and into western OR and southern WA this afternoon and into the
evening. An upper-level trough across the West Coast will overspread
a plume of monsoon moisture from northwestern CA to the OR Cascades
and central OR. PWATs generally below 0.90" and faster northeastward
storm motions will promote limited rainfall efficiency with some
potential for lightning. ERC values in the 80-90th percentile and
should promote the potential for ignitions, especially over OR where
faster storm motions are expected.

...Southern Plains...
Beneath the upper ridge, another day of very hot temperatures and
gusty southwesterly winds are expected over parts of the southern
Plains. Afternoon high temperatures over 100 F are likely from the
eastern TX Panhandle into central OK and southern KS. With this
heat, afternoon RH values are expected to fall to below 20%.
Bolstered by the strong heating and weak westerly flow aloft, a
surface trough will encourage southwesterly 15-20 mph surface winds
through the day. Given the very dry fuels, elevated fire-weather
conditions are probable.

Isolated thunderstorms are possible over northwestern portions of
the OK/TX Panhandles near a stalled front. While likely higher
based, weakening upper flow from the building ridge should limit
storm motions and dry thunderstorm potential. Still, lightning
interacting with drier fuels could support some potential for
ignitions.

...Please see www.spc.noaa.gov/fire for graphic product...