WW 655 SEVERE TSTM IN OH 050635Z - 051200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 655
NWS Storm Prediction Center Norman OK
235 AM EDT Sat Sep 5 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northeast Indiana
Northwest into North-Central Ohio
* Effective this Saturday morning from 235 AM until 800 AM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Scattered large hail events to 1.5 inches in diameter possible
SUMMARY...Strong to severe thunderstorms are expected tonight from
northeast Indiana into northwest/north-central Ohio. A few instances
of large hail are possible, but the primary severe risk is expected
to be damaging wind gusts.
The severe thunderstorm watch area is approximately along and 40
statute miles north and south of a line from 45 miles west northwest
of Fort Wayne IN to 65 miles east southeast of Findlay OH. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
30030.
...Mosier
WW 0655 Status Updates
STATUS REPORT ON WW 655
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 SSE AZO
TO 25 W FDY TO 20 ENE FDY TO 20 E MFD.
..LYONS..09/05/26
ATTN...WFO...IWX...ILN...CLE...
STATUS REPORT FOR WS 655
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
INC001-003-033-069-087-113-179-183-050940-
IN
. INDIANA COUNTIES INCLUDED ARE
ADAMS ALLEN DE KALB
HUNTINGTON LAGRANGE NOBLE
WELLS WHITLEY
OHC003-011-021-033-041-045-049-063-065-083-089-091-101-107-117-
125-137-139-149-159-161-175-050940-
OH
. OHIO COUNTIES INCLUDED ARE
ALLEN AUGLAIZE CHAMPAIGN
CRAWFORD DELAWARE FAIRFIELD
FRANKLIN HANCOCK HARDIN
KNOX LICKING LOGAN
MARION MERCER MORROW
PAULDING PUTNAM RICHLAND
SHELBY UNION VAN WERT
WYANDOT
MD 2240 CONCERNING SEVERE THUNDERSTORM WATCH 655... FOR NORTHEAST INDIANA INTO CENTRAL OHIO
Mesoscale Discussion 2240
NWS Storm Prediction Center Norman OK
0259 AM CDT Sat Sep 05 2026
Areas affected...Northeast Indiana into central Ohio
Concerning...Severe Thunderstorm Watch 655...
Valid 050759Z - 050930Z
The severe weather threat for Severe Thunderstorm Watch 655
continues.
SUMMARY...The severe threat continues across WW655. Strong to severe
gusts are possible with a complex of thunderstorms through the early
morning hours.
DISCUSSION...Thunderstorms ongoing from northeast IN to central OH
have gradually coalesced into several strong to severe clusters.
More linear structure has been noted with time suggesting a better
organized cold pool has developed. However, these storms likely
remain elevated above a partially stable boundary layer with
temperatures in the low 70s F. PWS data and surface observing
stations suggests mainly sub-severe gusts (45-50 mph) are reaching
the surface. Still, the environment and continued strengthening of
the cold pool will remain broadly supportive of strong to severe
gust potential tonight. Especially with any bowing segments or
forward propagating clusters that emerge.
..Lyons.. 09/05/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...RLX...CLE...ILN...IWX...IND...
LAT...LON 41618560 41198396 41028349 40768242 40508229 40228225
39968233 39778237 39658246 39468269 39388302 39378334
39918428 40678544 41618560
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1222 AM CDT Sat Sep 05 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF
THE OHIO VALLEY INTO THE SOUTHERN MID-ATLANTIC AND CAROLINAS...
...SUMMARY...
Severe thunderstorms capable of mainly damaging gusts are possible
across portions of the Ohio Valley into southern Mid-Atlantic and
Carolinas on Saturday afternoon and evening. Isolated occurrences of
large hail and severe wind gusts also appear possible over parts of
the northern and central Plains Saturday into Saturday night.
...Synopsis...
A prominent mid-level ridge will persist over the central CONUS
between upper lows over the Pacific Northwest and the Gulf of St.
Lawrence into NB/NS. Several weak disturbances (some of convective
origin) will progress through the periphery of the ridge, serving as
foci for thunderstorm development. At the surface, an area of low
pressure is forecast over the western Dakotas with an associated
boundary --the location of which may be modified by convective
outflow-- extending into the OH Valley and southern Mid-Atlantic.
The eastern extension of the boundary will begin to push south as a
cold front Saturday afternoon into night as high pressure builds
into the Great Lakes.
...Ohio Valley into the Carolinas...
A mature to decaying MCS is expected to be ongoing 12Z Saturday over
portions of the middle to upper OH Valley, aided by a subtle
mid-level disturbance/possible MCV. There is considerable
variability across the 00Z convection-allowing models in the
longevity and extent of the convective system over the central
Appalachians into southern Mid-Atlantic through the remainder of the
morning. Should the MCS remain intact, isolated occurrences of
damaging wind are possible.
Renewed thunderstorm development is likely by afternoon along the
residual MCS cold pool and/or synoptic front as temperatures in the
90s to around 100 combine with boundary-layer dewpoints in the low
to mid 70s to yield MLCAPE up to 2000-3000+ J/kg with steepening
low-level lapse rates. Additionally, the models indicate some
enhancement of mid-level winds in association with the
disturbance/MCV moving through the southern Mid-Atlantic during the
afternoon, which may yield more organized multicells and line
segments with the predominant hazard being damaging wind gusts into
the evening.
Farther to the west, additional strong to severe storms appear
possible along and ahead of the composite boundary from the vicinity
of the OH River south into the Cumberland Plateau where widely
scattered damaging wind gusts also appear possible.
...Northern and Central Plains...
A band of elevated thunderstorms is expected to be ongoing 12Z
Saturday, centered over eastern SD. That activity is expected to
diminish through the morning with the cessation of the nocturnal
low-level jet; however, isolated occurrences of large hail and
severe wind gusts appear possible prior to dissipation. In the wake
of the early-day storms, the presence of steep low/mid-level lapse
rates and richer boundary-layer moisture with eastward extent will
contribute to a moderately to strongly unstable air mass by
afternoon with MLCAPE of 2000-3500+ J/kg.
Nebulous forcing for ascent and capping relating to the proximity of
the mid-level ridge axis lead to uncertainty in the specific details
regarding the location and extent of surface-based thunderstorm
development during the afternoon into evening. However, the presence
of the surface low, outflow-modified surface front, and a lee trough
over the High Plains will be candidates for storm development. The
strongest deep-layer shear (30-40 kt) is forecast to the north of
the surface low and composite boundary over ND and northern SD into
western MN where a conditional risk of supercells capable of large
hail and severe wind gusts exists. Elsewhere, high-based pulse and
multicell storm modes appear possible with the primary hazard being
widely-spaced severe wind gusts.
The isolated severe threat may persist into the overnight hours in
the vicinity of a nocturnally strengthening low-level jet.
...Western Montana...
A belt of enhanced mid/upper-level flow will exist across the
region, to the east of the upper low over the Pacific Northwest.
Heating along the high terrain coupled with the possible influence
of a weak mid-level disturbance is expected to support an increase
in high-based showers and a few thunderstorms during the afternoon
and evening. While lapse rates will be steep with strong deep-layer
shear, the absence of appreciable moisture will limit MLCAPE to
generally less than 250 J/kg. As such the potential for severe wind
gusts is currently too low to warrant 5% wind probabilities.
..Mead/Chalmers.. 09/05/2026
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1212 AM CDT Sat Sep 05 2026
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTH CAROLINA AND GEORGIA...
...SUMMARY...
Strong wind gusts are likely across the Southeast Sunday afternoon
and early evening. A more uncertain risk for severe wind and hail is
expected across parts of Montana into the northern Plains and Middle
Missouri Valley.
...MT into the northern Plains and Mid-MO Valley...
The upper ridge centered over the Plains on Sunday will begin to
weaken and shift east as a western upper shortwave trough develops
eastward toward the northern Rockies. As this occurs, several
shortwave impulses will migrate through the top of the ridge over
the northern Plains and Mid-MO Valley. Southwesterly deep-layer flow
also will increase later in the period across MT and the High Plains
with the approaching of the upper trough. At the surface, low
pressure will be in place across eastern MT and the western Dakotas,
with a surface trough extending southward through the central High
Plains. Meanwhile, a warm front will be draped across northern ND,
while a quasi-stationary front extends northwest to southeast across
South Dakota into the MO-Valley. A moist airmass will reside along
these boundaries, and areas of moderate to strong instability are
forecast.
Most guidance depicts early day convection ongoing across parts of
MN and eastern SD. While evolution of this convection is uncertain,
it seems possible that it could persist and/or strengthen as it
shifts southwest across the Mid-MO Valley through afternoon.
Additional convection is expected to develop along the surface
trough over the High Plains, near the surface warm front, surface
low, and later in the evening across much of Montana with the
approach of the upper trough. Pockets of damaging winds and hail
will be possible. If confidence increases in areas of greater storm
coverage, higher probabilities may be needed in later outlooks.
...Southern States...
A weak low is expected to develop southward across GA as a surface
front sags southward through the period. Ahead of the front, a very
moist and unstable airmass will be in place, fostering areas of
moderate to strong instability. Deep-layer flow will remain light
and vertical shear weak, limiting organized severe potential.
However, given strong instability, high PWs, frontal forcing, and
sufficient storm coverage/clustering, isolated to scattered
strong/damaging wind gusts are expected.
..Leitman.. 09/05/2026
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0137 AM CDT Sat Sep 05 2026
Valid 071200Z - 081200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN AND CENTRAL PLAINS INTO WESTERN MINNESOTA...
...SUMMARY...
Strong to severe thunderstorms are possible across portions of the
northern and central Plains into Minnesota on Monday.
...Nebraska into the Dakotas and Minnesota...
An upper shortwave trough will eject east/northeast from the
Intermountain West to the northern Plains on Monday. Strong
mid/upper southwesterly flow will overspread the region ahead of the
trough. At the surface, a low over eastern MT will develop northeast
into the Canadian Prairies, and a trailing cold front will push east
across portions of NE/SD/ND. A moist airmass will be in place ahead
of the front, promoting areas of moderate instability. Vertically
veering wind profiles, and strengthening midlevel southwesterly
flow, will generate effective shear magnitudes greater than 35 kt,
supporting organized thunderstorms. While cooling aloft will result
in modestly steep lapse rates, warmer temperatures may linger around
850 mb, leading to capping concerns. Nevertheless, even elevated
storms will pose a risk for hail, and depending on storm mode,
strong wind gusts.
..Leitman.. 09/05/2026
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0244 AM CDT Sat Sep 05 2026
Valid 081200Z - 131200Z
...DISCUSSION...
...Days 4-6/Tue-Thu -- Central Plains to Great Lakes/Ohio Valley and
Mid-Atlantic...
An upper shortwave trough will shift east across the Upper
Midwest/Great Lakes and northeast through Thursday. An associated
surface low will mainly remain over Canada, but a trailing cold
front will sweep across parts of the central Plains and Upper
Midwest on Tuesday, before continuing south and east into Kansas and
across the Great Lakes on Wednesday. By Thursday, the boundary is
expected to continue south and east across the Ohio Valley and
Mid-Atlantic. Stronger large-scale ascent will likely remain focused
near and north of the international border. Furthermore, the
corridor of deeper boundary layer moisture may be somewhat limited,
especially Tuesday into Wednesday, due to a prior cold frontal
passage and surface high pressure over the Midwest. Nevertheless,
enhanced deep-layer flow, and corridors of at least modest
instability along the cold front could support some severe risk.
However, confidence in 15 percent or greater coverage is low at this
time frame.
...Days 7-8/Fri-Sat -- Northern/Central Plains to Upper Midwest...
At the end of the period, another upper shortwave trough may dig
southeast from the Pacific Northwest and into the Plains. Another,
perhaps stronger, cold front could sweep across the Plains and the
Mid/Upper MS Valley. Depending on moisture return in the wake of the
earlier cold frontal passage, some severe risk could develop during
the weekend. Furthermore, large spread exists among various guidance
regarding the evolution of the this upper trough, resulting in
uncertainty in greater corridors of severe potential.
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1251 AM CDT Sat Sep 05 2026
Valid 051200Z - 061200Z
...NO CRITICAL AREAS...
...Synopsis...
Similar to Friday, upper-level troughing will persist across the
Pacific Northwest and Northeast, with upper level ridging also
remaining centered over the southern Great Plains. Modestly strong
southwestern flow will continue across much of the Great Basin,
northern Rockies, and northern High Plains. This troughing pattern
and attendant precipitation, cloud cover, and cooler temperatures
will continue to largely limit fire weather concerns across the
western U.S. today. Elsewhere, a surface frontal system will
continue to bring chances for rain to portions of the Midwest/East
Coast.
...Central/Northern Wyoming...
While less widespread compared to Friday, sustained southwesterly
winds of 10-20 mph and RH values of 15-20% (locally down to 10%) may
overlap areas of receptive fuels across portions of central and
northern Wyoming this afternoon. These conditions may support
locally elevated fire weather concerns; however, the duration and
spatial extent of wind/RH overlap are forecast to remain relatively
limited. Thus, Elevated highlights have been withheld.
...Great Basin...
Southwesterly flow of 15-25 mph amid minimum RH values of 10-20%
will continue across the eastern/southern portions of the Great
Basin today. Locally elevated fire weather conditions may develop
where recent rainfall was minimal and/or where pockets of dry fuels
remain. Generally marginal fuels across this region are expected to
preclude a broader fire weather risk, however.
..Chalmers.. 09/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Sat Sep 05 2026
Valid 061200Z - 071200Z
...NO CRITICAL AREAS...
...Synopsis...
Persistent upper-level troughing over the Pacific Northwest and
Northeast will continue on Day 2/Sunday, with upper ridging
remaining in place over the southern Plains. A series of shortwave
troughs embedded within strengthening southwesterly flow will
transition northeastward across portions of the Great Basin/Northern
Rockies, which will begin to advect subtropical moisture into the
Desert Southwest/Great Basin, likely bringing additional cloud cover
and some chances for rain to the region. These factors will largely
mitigate fire weather concerns in the western U.S.
...Eastern Idaho into central/northern Wyoming...
Dry and breezy conditions are forecast across portions of eastern
Idaho and central/northern Wyoming Sunday afternoon. These
conditions may support locally elevated fire weather concerns across
this region, especially across central/northern Wyoming where drier
fuels exist. The expected limited duration and spatial extent of
meteorological conditions combined with uncertainty regarding cloud
cover and its impact on RH reductions precludes the addition of
Elevated highlights at this time, however.
...Central Great Basin...
Another day of dry, southwesterly flow is forecast across portions
of the central Great Basin. Locally elevated fire weather conditions
may develop where pockets of drier fine fuels exist; however, a
broader fire weather risk is not anticipated owing to generally
marginal fuels.
..Chalmers.. 09/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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