WW 657 SEVERE TSTM NC SC CW 051855Z - 060200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 657
NWS Storm Prediction Center Norman OK
255 PM EDT Sat Sep 5 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern North Carolina
Northeast South Carolina
Coastal Waters
* Effective this Saturday afternoon and evening from 255 PM until
1000 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Thunderstorm clusters will continue to pose a threat for
scattered severe/damaging winds as they spread east-southeastward
this afternoon and evening. Isolated severe hail may also occur with
any cells that can remain at least semi-discrete.
The severe thunderstorm watch area is approximately along and 90
statute miles east and west of a line from 25 miles northwest of
Elizabeth City NC to 40 miles southwest of Wilmington NC. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU7).
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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 656...
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
31030.
...Gleason
WW 656 SEVERE TSTM NC SC 051705Z - 060000Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 656
NWS Storm Prediction Center Norman OK
105 PM EDT Sat Sep 5 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Western and Central North Carolina
Western and Northern South Carolina
* Effective this Saturday afternoon and evening from 105 PM until
800 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Loosely organized thunderstorm clusters will likely pose a
threat for mainly scattered damaging winds as they spread
east-southeastward through the afternoon and evening. Isolated
severe hail may also occur with the stronger cores that develop.
The severe thunderstorm watch area is approximately along and 65
statute miles north and south of a line from 30 miles south
southwest of Asheville NC to 25 miles north of Goldsboro NC. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU6).
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
31030.
...Gleason
WW 0657 Status Updates
STATUS FOR WATCH 0657 HAS NOT BEEN ISSUED YET
WW 0656 Status Updates
STATUS FOR WATCH 0656 HAS NOT BEEN ISSUED YET
MD 2245 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WESTERN/CENTRAL SOUTH DAKOTA INTO WESTERN/CENTRAL NEBRASKA AND EASTERN COLORADO
Mesoscale Discussion 2245
NWS Storm Prediction Center Norman OK
0334 PM CDT Sat Sep 05 2026
Areas affected...western/central South Dakota into western/central
Nebraska and eastern Colorado
Concerning...Severe potential...Watch unlikely
Valid 052034Z - 052230Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated storms may produce marginally severe hail and
strong to severe wind this afternoon/evening.
DISCUSSION...Thunderstorms are developing near the surface trough
across the central Plains. Modifying the 18z sounding from LBF shows
MLCIN has weakened but remains. Moderate instability was sampled
above the capping layer. Remaining MLCIN is also depicted in SPC
Mesoanalysis across much of the central Plains, though temperatures
warming into the mid 90s across western Nebraska and eastern
Colorado are slowly eroding the remaining cap. Deep layer flow is
generally weak, which will likely keep the organized severe
potential low. However, deep layer shear around 20-30 kts may
support a few stronger cores capable of marginally severe hail.
Large dew point depressions and steep lapse rates will favor outflow
dominant storms capable of a few instances of strong to severe wind.
Overall, severe potential looks to remain too isolated for watch
issuance.
..Thornton/Gleason.. 09/05/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ABR...GID...LBF...UNR...GLD...BOU...CYS...
LAT...LON 39410352 41030377 42140364 42920356 45060320 45400295
45640247 45270123 44770090 44140078 44070082 43830063
43330034 42329983 41769988 40510035 39520239 39410352
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 2244 CONCERNING SEVERE THUNDERSTORM WATCH 656...657... FOR CENTRAL/EASTERN NC INTO PARTS OF SC AND NORTHEAST GA
Mesoscale Discussion 2244
NWS Storm Prediction Center Norman OK
0303 PM CDT Sat Sep 05 2026
Areas affected...Central/eastern NC into parts of SC and northeast
GA
Concerning...Severe Thunderstorm Watch 656...657...
Valid 052003Z - 052130Z
The severe weather threat for Severe Thunderstorm Watch 656, 657
continues.
SUMMARY...The threat for scattered damaging winds and isolated hail
will continue through late afternoon.
DISCUSSION...A broken band of thunderstorms is ongoing this
afternoon from central/northern NC into Upstate SC and far northeast
GA. Somewhat stronger deep-layer flow associated with an MCV is
spreading over NC, with weaker flow in place farther south and west.
Strong heating downstream of the ongoing storms has resulted in
substantial destabilization and steepening of low-level lapse rates,
which will continue to support potential for downbursts and loosely
organized outflow-driven clusters through late afternoon. Scattered
damaging winds will continue to be the primary hazard, with isolated
hail also possible.
..Dean.. 09/05/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...MHX...RAH...ILM...CAE...GSP...FFC...
LAT...LON 33738194 33698309 34518349 34778168 35118057 35467986
35767926 36097813 36197697 36087648 35667624 35227622
34617677 34127764 33907928 33758085 33738194
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 2243 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN ILLINOIS...SOUTHERN INDIANA...SOUTHERN OHIO...AND PORTIONS OF CENTRAL/EASTERN KENTUCKY
Mesoscale Discussion 2243
NWS Storm Prediction Center Norman OK
0301 PM CDT Sat Sep 05 2026
Areas affected...eastern Illinois...southern Indiana...southern
Ohio...and portions of central/eastern Kentucky
Concerning...Severe potential...Watch unlikely
Valid 052001Z - 052200Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated instances of strong to severe wind and marginally
severe hail possible this afternoon.
DISCUSSION...Thunderstorms are re-developing across portions of the
Ohio Valley this afternoon. Clearing skies behind morning convection
has allowed for ample daytime heating/warming with temperatures in
the low to mid 90s and moderate instability. Deep layer flow is
generally weak across the region, which will likely limit a more
organized severe threat. Nonetheless, the hot and moist air mass may
support water loaded downdrafts and a few instances of strong to
severe wind. Effective bulk shear around 25 kts along and north of a
weak frontal boundary across the region may support a few instances
of marginally severe hail. Overall, this threat is expected to
remain too localized for watch issuance.
..Thornton/Gleason.. 09/05/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...RLX...MRX...JKL...ILN...LMK...IND...PAH...ILX...
LAT...LON 39688229 39828282 40148497 40368671 39798803 38978864
38218785 37448668 37058576 36748468 36598342 36988248
37628198 38078178 39038188 39298194 39688229
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1122 AM CDT Sat Sep 05 2026
Valid 051630Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL APPALACHIANS INTO SOUTHERN VIRGINIA AND THE CAROLINAS...
...SUMMARY...
Strong to severe thunderstorms capable of producing scattered
damaging winds should occur this afternoon/evening across parts of
the central Appalachians into southern Virginia and the Carolinas.
Isolated large hail and severe winds may also occur over parts of
the northern/central Plains through tonight.
...Ohio Valley/Central Appalachians into the Mid-Atlantic and
Carolinas...
An earlier MCS across the OH Valley has weakened as it crossed/moved
eastward over the central Appalachians. The strongest remaining
convective segment is ongoing late this morning across parts of
southwest VA/northeast TN. Robust destabilization is expected to
continue this afternoon downstream of this activity across southern
VA into the Carolinas, with MLCAPE peaking around 2500-3500 J/kg
over central/eastern NC. This region will be on the southern
periphery of modestly enhanced mid-level west-northwesterly flow,
and sufficient deep-layer shear will be present to maintain some
convective organization.
Current expectations are for one or more thunderstorm clusters to
gradually increase in intensity this afternoon as they spread
eastward across southern VA and central/eastern NC, with some
uncertainty whether the ongoing convection will restrengthen, or if
new development will occur along its outflow. Regardless, latest
guidance and observational trends still suggest that a relatively
greater threat for damaging winds should exist this afternoon across
central/eastern NC and vicinity, where the greatest thunderstorm
coverage, maxima in MLCAPE/DCAPE, and steepened low-level lapse
rates are forecast. Have therefore introduced higher severe wind
probabilities (30% area) across this region. Isolated hail may also
occur with the strongest cores that can develop, although mid-level
lapse rates are expected to remain rather poor. Severe potential
should gradually wane this evening with the loss of daytime heating,
and as convection moves offshore.
Farther west, outflow from the morning thunderstorms may serve as a
focus for renewed thunderstorm development this afternoon from parts
of the OH Valley southeastward into the TN Valley. This region will
be displaced from the stronger flow aloft present over the
Mid-Atlantic/Northeast, with weak deep-layer shear expected. Still,
some risk for isolated damaging winds may exist with any loosely
organized cells/clusters that can develop given the presence of
moderate to locally strong instability.
...Northern/Central Plains...
A highly amplified mid/upper-level ridge will remain anchored over
the central CONUS into south-central Canada through the period, with
generally neutral to weakly rising mid-level heights expected over
the northern/central Plains. Ongoing elevated cells across northern
ND may continue to pose an isolated severe hail threat in the short
term, but weakening low-level warm advection should tend to result
in a further decrease in intensity with this activity. Otherwise,
additional isolated to perhaps widely scattered high-based
thunderstorms may develop this afternoon along/east of a surface lee
trough over the northern/central Plains. While mid-level flow and
related effective bulk shear should remain weak, occasional severe
gusts may still occur with convective downdrafts given a well-mixed
boundary layer. Some risk for hail and gusty winds may also exist
with elevated convection that should eventually develop tonight into
early Sunday morning in a renewed/modest low-level warm advection
regime.
...Western Montana...
To the east of a closed mid-level low over WA/OR, a belt of enhanced
southwesterly mid/upper-level winds will extend across the northern
Rockies. Gradually increasing moisture and large-scale ascent aloft
associated with a weak/embedded shortwave trough are expected to
support an increase in isolated thunderstorms this
afternoon/evening. Lapse rates through low/mid levels will be steep
with strong deep-layer shear present, but modest low-level moisture
should limit MLCAPE to generally less than 500 J/kg. The potential
for severe wind gusts still appears too low to justify including 5%
wind probabilities at this time.
..Gleason/Thornton.. 09/05/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sat Sep 05 2026
Valid 052000Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CAROLINAS INTO SOUTHEASTERN VIRGINIA...
...SUMMARY...
The threat of strong to severe thunderstorms capable of producing
scattered damaging winds will continue this afternoon/evening across
parts of the Carolinas and southern Virginia. Isolated large hail
and severe winds may also occur over parts of the northern/central
Plains through tonight.
...20Z Update...
Only minor changes were made with this update. The SLGT Risk was
trimmed behind an east-southeastward moving band of convection
moving across the Carolinas. While isolated redevelopment cannot be
entirely ruled out in the wake of this activity, the primary severe
risk will continue spreading eastward to the coast into this
evening.
Farther west, 5-percent hail probabilities were added in parts of
the lower OH Valley. Here, relatively steep deep-layer lapse rates,
around 30 kt of effective shear, and a cellular mode may support
isolated instances of marginally severe hail.
Elsewhere, the previous forecast remains on track.
..Weinman.. 09/05/2026
.PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Sep 05 2026/
...Ohio Valley/Central Appalachians into the Mid-Atlantic and
Carolinas...
An earlier MCS across the OH Valley has weakened as it crossed/moved
eastward over the central Appalachians. The strongest remaining
convective segment is ongoing late this morning across parts of
southwest VA/northeast TN. Robust destabilization is expected to
continue this afternoon downstream of this activity across southern
VA into the Carolinas, with MLCAPE peaking around 2500-3500 J/kg
over central/eastern NC. This region will be on the southern
periphery of modestly enhanced mid-level west-northwesterly flow,
and sufficient deep-layer shear will be present to maintain some
convective organization.
Current expectations are for one or more thunderstorm clusters to
gradually increase in intensity this afternoon as they spread
eastward across southern VA and central/eastern NC, with some
uncertainty whether the ongoing convection will restrengthen, or if
new development will occur along its outflow. Regardless, latest
guidance and observational trends still suggest that a relatively
greater threat for damaging winds should exist this afternoon across
central/eastern NC and vicinity, where the greatest thunderstorm
coverage, maxima in MLCAPE/DCAPE, and steepened low-level lapse
rates are forecast. Have therefore introduced higher severe wind
probabilities (30% area) across this region. Isolated hail may also
occur with the strongest cores that can develop, although mid-level
lapse rates are expected to remain rather poor. Severe potential
should gradually wane this evening with the loss of daytime heating,
and as convection moves offshore.
Farther west, outflow from the morning thunderstorms may serve as a
focus for renewed thunderstorm development this afternoon from parts
of the OH Valley southeastward into the TN Valley. This region will
be displaced from the stronger flow aloft present over the
Mid-Atlantic/Northeast, with weak deep-layer shear expected. Still,
some risk for isolated damaging winds may exist with any loosely
organized cells/clusters that can develop given the presence of
moderate to locally strong instability.
...Northern/Central Plains...
A highly amplified mid/upper-level ridge will remain anchored over
the central CONUS into south-central Canada through the period, with
generally neutral to weakly rising mid-level heights expected over
the northern/central Plains. Ongoing elevated cells across northern
ND may continue to pose an isolated severe hail threat in the short
term, but weakening low-level warm advection should tend to result
in a further decrease in intensity with this activity. Otherwise,
additional isolated to perhaps widely scattered high-based
thunderstorms may develop this afternoon along/east of a surface lee
trough over the northern/central Plains. While mid-level flow and
related effective bulk shear should remain weak, occasional severe
gusts may still occur with convective downdrafts given a well-mixed
boundary layer. Some risk for hail and gusty winds may also exist
with elevated convection that should eventually develop tonight into
early Sunday morning in a renewed/modest low-level warm advection
regime.
...Western Montana...
To the east of a closed mid-level low over WA/OR, a belt of enhanced
southwesterly mid/upper-level winds will extend across the northern
Rockies. Gradually increasing moisture and large-scale ascent aloft
associated with a weak/embedded shortwave trough are expected to
support an increase in isolated thunderstorms this
afternoon/evening. Lapse rates through low/mid levels will be steep
with strong deep-layer shear present, but modest low-level moisture
should limit MLCAPE to generally less than 500 J/kg. The potential
for severe wind gusts still appears too low to justify including 5%
wind probabilities at this time.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 PM CDT Sat Sep 05 2026
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
GEORGIA AND THE CAROLINAS...
...SUMMARY...
Damaging wind gusts are likely across portions of the Southeast
Sunday afternoon and early evening. Additional areas at risk for
severe wind and hail are across parts of northern Utah northward
into Montana and east into the northern Plains and Middle Missouri
Valley.
... Synopsis ...
A high-amplitude mid-level ridge will persist across the central US
on Sunday, with troughing across both the east and west coasts.
Embedded within the basal region of the western trough, a closed low
should open up and take on a negative tilt as it moves along the
northwest periphery of the central ridge.
At the surface, an anticyclone will be located across the upper
Great Lakes, ushering in a cooler, drier air mass from the Upper
Midwest east across the Ohio Valley into the Northeast. Demarcating
the boundary between this continental air mass and the more maritime
air mass to the south and west will be a front stretched from the
Minnesota-North/South Dakota border south and east to southeast
Missouri and then east from there to the East Coast.
... Southeast ...
A very humid air mass will be in place across the region, with HREF
mean dewpoint temperatures in the upper-60Fs to low-70Fs. Diurnal
heating will allow afternoon temperatures to warm into the
low-to-mid-90Fs, yielding MUCAPE values in excess of 1500 J/kg.
(High-resolution guidance is generally in the 1500-2500 J/kg range,
with coarser-scale guidance, such as the RAP, showing perhaps as
high as 4000 J/kg.)
Scattered thunderstorms will develop during the afternoon as
convective temperatures are reached. Precipitable water values
around 2 inches and DCAPE values in excess of 1000 J/kg will support
heavy, water-laden downbursts capable of scattered wind damage.
Slightly better deep-layer shear across portions of Georgia and the
Carolinas may support at least transient thunderstorm organization
in the form of multi-cell clusters which may pose a slightly greater
risk of organized wind damage.
... Mid-Missouri Valley and Northern Plains ...
Thunderstorms may be ongoing at the start of the forecast period
across portions of the area or develop shortly thereafter. These
thunderstorms will likely be driven by strong warm-air advection
near the apex of the mid-level ridge. These storms may initially
pose a risk of large hail and gusty winds. With time, diurnal
heating may support a transition from elevated-to-surface based
thunderstorms, increasing the potential for damaging winds,
especially as low-level lapse rate steepen. Deep-layer shear will
support individual storms moving southeast while the larger-scale
evolution will be toward the southwest.
The exact evolution of this convection, in particular where the
narrow corridor develops, remains a bit uncertain. As confidence
increases in the location of these storms, higher severe weather
probabilities may be needed.
... Northwest Utah into Montana ...
As the western mid-level low opens and takes on a negative tilt as
it traverses the northwest periphery of the central US ridge,
large-scale ascent will support scattered thunderstorm development
across portions of northwest Utah, Idaho, and western Wyoming.
Strong mid-level flow (around 50 knots at 500 millibars) coupled
with a deep, well-mixed boundary layer will support downward
momentum transfer within these thunderstorms capable of producing
scattered wind damage. These storms will quickly move northeast into
Montana during the evening hours. If coverage of these storms is
greater than expected, higher wind probabilities would be warranted
in subsequent outlooks.
..Marsh.. 09/05/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0244 PM CDT Sat Sep 05 2026
Valid 071200Z - 081200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN PLAINS AND MINNESOTA...
...SUMMARY...
Strong to severe thunderstorms are possible across portions of the
northern and central Plains into Minnesota on Monday.
... Northern Plains into the Upper Great Lakes ...
A mid-level shortwave trough will lift northeast on Monday,
impinging on the central US ridge. Strong southwesterly mid-level
flow associated with the trough will overspread an increasingly warm
and moist low-level airmass across the north-central US. Given
low-level flow will be more southerly, the resulting vertically
veering profiles will result in effective shear ranging from 35
knots to more than 50 knots. Forecast soundings indicate that an
elevated mixed layer should advect over the Plains during the day
resulting in capping issues for most of the afternoon. However, as
cooler mid-level temperatures overspread the unstable and sheared
airmass, afternoon thunderstorms will at least be possible. These
storms should pose a threat for large hail and, if the storms can
tap into the boundary layer, strong thunderstorm winds. As the
low-level jet increases during the evening, an increase in storm
coverage is expected, with perhaps one or more MCSs evolving across
portions of the eastern Dakotas and Minnesota. Isolated large hail
and perhaps damaging winds will be possible.
..Marsh.. 09/05/2026
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1129 AM CDT Sat Sep 05 2026
Valid 051700Z - 061200Z
...NO CRITICAL AREAS...
As an upper low remains anchored over the Pacific Northwest, strong
southwesterly flow atop the Great Basin will continue to enhance a
very dry boundary layer amid breezy sustained southerly winds of
20-25 mph (gusts up to 35 mph or greater) this afternoon.
Meteorological conditions would otherwise support an elevated (or
perhaps critical) fire weather threat in southern Nevada and western
Utah, but a marginal fuelscape averts any risk areas. Please see the
previous discussion for more details.
..Elizalde-Garcia.. 09/05/2026
.PREV DISCUSSION... /ISSUED 1251 AM CDT Sat Sep 05 2026/
...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.
...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
0130 PM CDT Sat Sep 05 2026
Valid 061200Z - 071200Z
...NO CRITICAL AREAS...
The forecast remains on track for Day 2/Sunday; please see the
previous discussion for more information.
..Elizalde-Garcia.. 09/05/2026
.PREV DISCUSSION... /ISSUED 1253 AM CDT Sat Sep 05 2026/
...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.
...Please see www.spc.noaa.gov/fire for graphic product...
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0354 PM CDT Sat Sep 05 2026
Valid 071200Z - 131200Z
...Discussion...
An upper shortwave trough will eject from the Intermountain West
into the northern Plains and Upper Midwest early next week, allowing
high pressure to retrograde into the western CONUS through Day
5/Wednesday. Meanwhile, persistent ridging over the southern Plains
will continue to promote above normal temperatures and dry
conditions through the forecast period, although accompanied by
relatively light surface winds. Predictability wanes beyond Day
6/Thursday with disagreement in extended ensemble guidance on the
evolution of the upper pattern -- particularly with eastern Pacific
troughing and the remnants of Hurricane Marie. However, members are
generally in agreement for another shortwave trough to sag into the
Pacific Northwest from British Columbia on Days 6-7/Thursday-Friday,
transporting cooler temperatures and precipitation chances to the
region.
As the aforementioned upper trough translates northeastward through
Day 4/Tuesday, advecting subtropical moisture will provide
opportunities for accumulating rainfall along the Central
U.S./Canadian border. Despite somewhat cooler daytime temperatures,
a drier airmass and strong southwesterly flow aloft should bring
fire weather concerns back into the north-central states early next
week. 40% Critical probabilities have been introduced across parts
of the northern Plains on Days 3-4/Monday-Tuesday where RH values of
less than 20% and gusty winds of 15-20 mph will overlap
rainfall-neglected fuels (and forecast ERCs remain at the 80-95th
percentiles).
..Elizalde-Garcia.. 09/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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