ACUS48 KWNS 290812
SWOD48
SPC AC 290811

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0311 AM CDT Thu May 29 2025

Valid 011200Z - 061200Z

...DISCUSSION...
...Sunday/Day 4 and Monday/Day 5...
On Sunday and Monday, a mid-level ridge is forecast to move eastward
across the north-central U.S. A low-level jet is forecast to develop
in the High Plains on Sunday with this feature strengthening on
Monday, as a trough moves through the Rockies. In response,
low-level moisture will increase across the Great Plains, allowing
for moderate destabilization across much of the region during the
day. Scattered thunderstorm development is expected Monday from
parts of the southern and central High Plains, northeastward along a
cold front into the Dakotas. Although deep-layer shear is not
forecast to be particular strong, the models do suggest that strong
instability will be possible across parts of the Dakotas by late
Monday afternoon. This likely would support a large hail and
wind-damage threat.

...Tuesday/Day 6 to Thursday/Day 8...
On Tuesday, the shortwave mid-level trough is forecast to move
eastward into the southern and central High Plains. Scattered
thunderstorms are expected Tuesday afternoon from the mid Missouri
Valley southward into eastern Kansas and east-central Oklahoma. In
addition to moderate/strong instability, large-scale ascent and
moderate deep-layer shear should support a severe threat during the
afternoon and evening. Supercells would be possible, with isolated
large hail and wind damage. Tornadoes could also occur.

On Wednesday, the cold front is forecast to move southeastward into
the mid Mississippi Valley, and southward into the southern Plains.
Mid-level flow near the front will be southwesterly. Ahead of the
front, surface dewpoints should be from the 60s to the mid 70s F,
which will contribute to moderate instability by afternoon. Although
deep-layer shear is not expected to be that strong near the front,
the instability should be enough for isolated severe storms in areas
where strong surface heating occurs. Predictability is low
concerning where the greater severe threat will be.

On Thursday, the front is forecast to move into the Southeast.
Thunderstorm development will be possible by afternoon along and
ahead of the front, from the Texas Coastal Plain northeastward into
the Gulf Coast states. Although moderate instability should be in
place in some areas by afternoon, deep-layer shear is forecast to be
weak enough to keep any severe threat localized.

..Broyles.. 05/29/2025

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ACUS48 KWNS 300901
SWOD48
SPC AC 300859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Fri May 30 2025

Valid 021200Z - 071200Z

...DISCUSSION...
As mentioned in WPC's Extended Forecast Discussion, an amplified
split-flow pattern across the CONUS renders below-average
predictability through the period. Will maintain inherited
severe-weather areas for D4-5, with mesoscale severe potential
evident in D6 and beyond but with poor synoptic predictability.

...D4/Monday...
A positive-tilt mid/upper trough should shift east as an embedded
shortwave impulse over the northern Rockies tracks near the
international border over the northern Great Plains. A northeast/southwest-oriented cold front should accelerate southward
into the central High Plains while a weak frontal wave temporarily
stalls the front over the Red River Valley of the North. There are
pronounced signals for afternoon to evening convection along the
front. Initially steep mid-level lapse rates will be supportive of
scattered severe potential. But it appears that stronger mid-level
flow may lag to the cool side of the front, which may limit a
greater threat.

...D5/Tuesday...
Complex severe potential is expected across the central states.
Low-amplitude shortwave impulses should be progressing across parts
of the northern Upper Midwest to the central High Plains on Tuesday
morning. Some guidance suggests extensive overnight convection may
be ongoing within a favorably diffluent upper-flow regime,
characterized by a coupled southern-stream left-exit and
northern-stream right-entrance regime. This renders substantial
uncertainty on where more robust boundary-layer destabilization
should occur. Warm mid-level temperatures in the southern stream
should yield modest mid-level lapse rates, which further lowers
confidence. Nevertheless, a broad and rich moist sector and adequate
deep-layer shear, along with widespread convection during the afternoon/evening, indicate scattered severe storms remain possible.

..Grams.. 05/30/2025

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ACUS48 KWNS 310856
SWOD48
SPC AC 310854

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CDT Sat May 31 2025

Valid 031200Z - 081200Z

...DISCUSSION...
Somewhat greater confidence exists for a more south-southwest to north-northeast oriented swath of severe on D4/Tuesday. This appears
focused from the southern Great Plains to the Midwest from midday
into early evening. Overall pattern appears less amplified after D4,
with nebulous severe potential in the central to eastern states.

...D4/Tuesday...
A low-amplitude southern-stream shortwave impulse may phase with a northern-stream shortwave trough in the Upper Great Lakes vicinity
by late Tuesday. The accompanying surface wave over KS may similarly
track northeastward along a cold front through the Upper Midwest.
Rich low-level moisture will become more prevalent ahead of the
front and should spread into at least WI. Extensive convection may
be ongoing at 12Z within an increasingly favorable diffluent
upper-flow regime that is coupled with a broad low-level jet. Amid
relatively warm 500-mb temperatures within the southwest flow regime
attendant to the southern-stream impulse, mid-level lapse rates will
likely be weak in the warm-moist sector. Where appreciable
boundary-layer heating can occur ahead of morning convection,
scattered severe storms are possible.

...D5-8/Wednesday-Saturday...
Weak mid-level lapse rates will be pervasive, suggesting that robust
diurnal heating will largely drive daily bouts of seemingly
lower-probability severe. Guidance consensus suggests a more zonal
mid-level flow regime may evolve towards D7/Friday, which would aid
in the development/expansion of the elevated mixed layer and a
return of steep mid-level lapse rates across the High Plains.

..Grams.. 05/31/2025

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ACUS48 KWNS 010832
SWOD48
SPC AC 010830

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CDT Sun Jun 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
Enhanced mid-level southwesterlies initially present over the
central Great Lakes early Wednesday should become confined to ON/QC
as a lower-amplitude shortwave trough dampens. Trailing to the south
of this, low-probability severe is apparent on Wednesday afternoon
in the eastern Midwest, and on Thursday afternoon over the Northeast along/ahead of a decaying cold front.

Another southern-stream shortwave impulse is progged to move east
from the Southwest mid-week. But initial surface ridging downstream
over the southern High Plains suggests the potential severe area
will be limited. Greater potential may await D6-7/Friday-Saturday,
as the ridging breaks down and zonal mid-level flow returns in the
wake of the aforementioned impulse. This will yield strengthening
and expansion of the EML east of the CO Plateau. ML guidance from
both the latest 00Z SPC/NSSL GEFS and yesterday's 00Z NCAR ECENS
highlight 15 percent probabilities on D6-7/Friday-Saturday across
the TX Panhandle into western KS/OK. Potential MCVs embedded within
this regime appear too minor at this time frame to reliably
delineate an area, but bear watching for shorter-term outlooks.

..Grams.. 06/01/2025

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ACUS48 KWNS 020841
SWOD48
SPC AC 020839

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0339 AM CDT Mon Jun 02 2025

Valid 051200Z - 101200Z

...DISCUSSION...
Latest guidance has trended towards a climatologically active
extended period for severe potential. It appears that 15 percent
severe areas will likely be delineated each day within a persistent
split-flow regime. Belts of enhanced mid-level westerlies should
accompany the train of low-amplitude southern-stream shortwave
impulses. Meanwhile, above-average agreement exists with the
amplification of a large-scale trough into the north-central states
towards the end of the period. This would suppress the southern
stream southward in the southern Great Plains to Deep South.

Reliably timing individual low-amplitude impulses/MCVs can be
difficult in this setup. But it appears that the initial impulse
ejecting across the southern Rockies around 12Z Thursday should
serve to focus severe potential from the TX Panhandle into southern
KS on D4. This feature may continue eastward towards the Mid-MS
Valley/eastern Midwest on D5/Friday. But with probable weak
mid-level lapse rates downstream and lack of run-to-run continuity
across guidance, will defer on a 15 percent area highlight.

..Grams.. 06/02/2025

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ACUS48 KWNS 030852
SWOD48
SPC AC 030851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Tue Jun 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
An active severe-weather pattern for repeated MCS development is
anticipated through this weekend, with more nebulous potential early
next week.

Medium-range guidance has converged to above-average consistency
with the large-scale pattern through this weekend. Enhanced zonal
mid-level flow within the southern stream should overlie a
seasonably rich and unstable air mass across the southern Great
Plains to the Deep South. Initial signal for south-central High
Plains nocturnal MCS development spreading east-southeast onto the
lower plains is evident late D3 and this will probably repeat on
D4/Friday night and perhaps on D5/Saturday night. This should
subside as a northern-stream upper trough amplifies into the
north-central states.

Remnant MCVs should focus downstream diurnal thunderstorm
development each afternoon through at least D6/Sunday. Given the
buoyancy/shear parameter space, sufficient confidence exists for
highlighting a scattered severe-storm threat on D4-5. Damaging winds
appear to be the dominant hazard in this pattern. An additional area
on D6 is plausible in later outlooks somewhere in the Deep South and
Gulf Coast States. For D7-8, severe potential is nebulous, but may
be tied to the evolution of the north-central states trough.

..Grams.. 06/03/2025

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ACUS48 KWNS 030919
SWOD48
SPC AC 030918

Day 4-8 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0418 AM CDT Tue Jun 03 2025

Valid 061200Z - 111200Z

CORRECTED FOR MISSING LABEL ON DAY 6

...DISCUSSION...
An active severe-weather pattern for repeated MCS development is
anticipated through this weekend, with more nebulous potential early
next week.

Medium-range guidance has converged to above-average consistency
with the large-scale pattern through this weekend. Enhanced zonal
mid-level flow within the southern stream should overlie a
seasonably rich and unstable air mass across the southern Great
Plains to the Deep South. Initial signal for south-central High
Plains nocturnal MCS development spreading east-southeast onto the
lower plains is evident late D3 and this will probably repeat on
D4/Friday night and perhaps on D5/Saturday night. This should
subside as a northern-stream upper trough amplifies into the
north-central states.

Remnant MCVs should focus downstream diurnal thunderstorm
development each afternoon through at least D6/Sunday. Given the
buoyancy/shear parameter space, sufficient confidence exists for
highlighting a scattered severe-storm threat on D4-5. Damaging winds
appear to be the dominant hazard in this pattern. An additional area
on D6 is plausible in later outlooks somewhere in the Deep South and
Gulf Coast States. For D7-8, severe potential is nebulous, but may
be tied to the evolution of the north-central states trough.

..Grams.. 06/03/2025

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ACUS48 KWNS 040853
SWOD48
SPC AC 040851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Wed Jun 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
Another active day characterized by an ongoing MCS and remnant
downstream MCVs is anticipated on D4/Saturday, with a broad belt of
mainly damaging wind potential evident. Seasonably strong mid-level
westerlies are expected to remain coincident with rich low-level
moisture. Ample buoyancy should diurnally develop south of
pre-existing outflows. This multi-day pattern finally breaks down
into D5/Sunday with amplification of a large-scale trough from the
southern Prairie Provinces into the Upper Midwest. Mesoscale-focused
severe potential may linger into at least D5/Sunday over the
southern High Plains to the TX/OK Red River Valley and from the
central Gulf to south Atlantic Coasts.

Otherwise, low-probability severe potential could begin in a portion
of the northern Great Plains on D4/Saturday, in association with the
amplifying trough. This should subsequently shift eastward and
likely broaden across the Great Lakes into the Northeast through
early next week. Overall instability appears modest until a
potential increase later when stronger flow fields overlap richer
low-level moisture. Daily severe probabilities appear to be sub-15
percent at this range, with a relative maximum in the
D6-7/Monday-Tuesday timeframe over the Northeast. Current timing of
this trough exiting New England by around D8/Wednesday suggests a
relative minimum across the CONUS then.

..Grams.. 06/04/2025

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ACUS48 KWNS 050858
SWOD48
SPC AC 050856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Thu Jun 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
The active severe-weather pattern from the southern High Plains to
the Southeast should persist into D4/Sunday. A low-amplitude
mid-level trough is progged across the Southeast with a belt of
enhanced westerlies. The degree of ongoing convection on Sunday
morning lowers confidence on how broad a region of scattered
severe-storm potential exists in the Southeast. The best area for less-impactful morning convection appears to be across the South
Atlantic Coastal Plain and adjacent eastern Piedmont. Scattered
damaging winds should be the main hazard from afternoon storms in
this region.

With a brief respite in the wake of multiple MCSs on D1 to early D3,
buoyancy should become large to locally extreme across a portion of
the southern High Plains to OK/TX Red River Valley by Sunday
afternoon. Latest guidance is quite insistent on more widespread
convective development during the late afternoon into Sunday night,
along the persistent quasi-stationary front. Although
mid/upper-level winds may be weaker relative to prior days, an
increased west-northwesterly component along with the very unstable
airmass will support severe hail/wind, which could be significant.

Guidance has shown less predictability in the D5-6/Monday-Tuesday
time frame. This seems related to handling of downstream MCV
evolution from the probable Sunday night MCS over OK/TX, as well as
individual shortwave impulses embedded within the broad upper trough
over the Upper Midwest to Great Lakes. Expansive swaths of
low-probability severe are evident across the southern to eastern
states but predictability is too low for any 15 percent highlights.
By mid-week, guidance is still signaling a reduction in overall
severe potential with a synoptic pattern change to predominantly
weak shear coincident with areas of moderate to large buoyancy.

..Grams.. 06/05/2025

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ACUS48 KWNS 060853
SWOD48
SPC AC 060852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CDT Fri Jun 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
A large MCS may be ongoing across the Ark-La-Tex vicinity on
D4/Monday morning. This MCS and attendant flow enhancement with its
MCV may support scattered damaging wind potential into the afternoon
downstream across the Deep South. How extensive an organized wind
threat persists is quite nebulous, given background mid-level
westerlies being weaker across the Southeast compared to prior days.

Sub-15 percent severe potential remains apparent across the Upper OH
Valley to Lower Great Lakes on D4/Monday, shifting east into the Northeast/Mid-Atlantic States on D5/Tuesday. A belt of strong
mid-level southwesterlies ahead of broad Great Lakes trough should
overlap parts of a weak cold front arcing south from a primary
surface cyclone over northeast ON to James Bay. Substantial
instability ahead of the front appears uncertain with progged weak
mid-level lapse rates and muted boundary-layer heating where the
stronger flow resides.

During D6-8/Wednesday-Friday, guidance continues to signal a
reduction in severe potential, as predominantly weak deep-layer
shear overlaps areas of moderate to large buoyancy.

..Grams.. 06/06/2025

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ACUS48 KWNS 070842
SWOD48
SPC AC 070841

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CDT Sat Jun 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
Sub-15 percent severe potential remains apparent over the Mid-Atlantic/Northeast States on D4/Tuesday before a cold front
moves offshore. Instability progs remain weak where at least
moderate deep-layer shear is anticipated. It seems plausible that
the northern extent of larger buoyancy will be suppressed south in
the wake of extensive convection through D3 across the Southeast.

On D5-6/Wednesday-Thursday, guidance has trended towards some
amplification of a minor southern-stream shortwave impulse as it
drifts across the southern Great Plains. This could foster mesoscale
corridors of modest shear overlapping plentiful buoyancy in the
south-central states.

Western Gulf moisture will spread north and encompass much of the
central states through next weekend. Various shortwave impulses over
the Northwest may support multiple bouts of mesoscale-driven severe
potential along the northern periphery of the expansive Great Plains
buoyancy plume.

..Grams.. 06/07/2025

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ACUS48 KWNS 090849
SWOD48
SPC AC 090847

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CDT Mon Jun 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
Guidance remains supportive of a more active pattern across the
northern High Plains to the Upper Midwest. GEFS-based ML guidance
from SPC and NSSL depict mesoscale areas of 15 percent
probabilities, centered on eastern MT to the Dakotas. While
predictability for a specific day remains too low, the signal exists
for increasing potential during the weekend to early next week.

The initial low-amplitude shortwave trough over WY/eastern MT at 12Z
Thursday is progged to dampen as it moves east into the Upper
Midwest. An area-of-interest is evident over western SD and the NE
Panhandle on D4/Thursday afternoon, but a favorable buoyancy/shear
combination is too spatially confined for a 15 percent highlight.

A broad swath of moderate to strong mid-level southwesterlies may
persist for multiple days across the Northwest, downstream of a
large-scale trough near the West Coast. At the same time, the
expansive buoyancy plume over the central states should increase
northwestward, building higher CAPE into the northern High Plains
this weekend. Still, poor predictability persists with the
spatiotemporal details of individual shortwave impulses that may
support daily severe threats on D6-8/Saturday-Monday.

..Grams.. 06/09/2025

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ACUS48 KWNS 100849
SWOD48
SPC AC 100848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Tue Jun 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Models are in good agreement with the overall pattern through about
Sunday/D6, depicting upper ridging over the northern Plains and
rising heights across the Northeast and general troughiness over the
Northwest. During that same period, the disturbance over the
southern Plains is forecast to lift toward the mid MS Valley with
weakening trend.

The greatest risk of severe storms will generally stretch from the
northern Rockies into the northern Plains, as weak but backed
low-level winds maintain a moist plume out of the central Plains and
into MT and the Dakotas.

On Friday/D4, scattered strong storms may occur over central MT,
beneath modest southwest winds aloft and with around 1000 J/kg
MUCAPE. Instability will build further in the Saturday/D5 to
Sunday/D6 time frame, with greater storm coverage expected. However,
winds aloft will be marginal. Still, developing west to northwest
flow aloft could eventually result in an MCS pattern with attendant
wind potential. Predictability is low at this time, but the northern
and central Plains region will be monitored over the next several
days for potential categorical risk outlines.

..Jewell.. 06/10/2025

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ACUS48 KWNS 110839
SWOD48
SPC AC 110838

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CDT Wed Jun 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
For Saturday/D4 into Sunday/D5, moderate southwest flow aloft will
remain over the Pacific Northwest and toward the northern Rockies,
with a gradual flattening of the upper ridge over the northern
Plains. Then through Wednesday/D8, modest west/northwest flow aloft
is likely to persist over the High Plains. Models diverge greatly
after this time frame. However, this pattern will generally favor
daily thunderstorms along the length of the High Plains, from MT
into eastern NM during the afternoon, and persisting into parts of
the Great Plains during the evenings.

The primary driver of severe potential will be a large area of
moderate to strong instability with 2000-3000+ J/kg MUCAPE
developing daily. As storms move off the higher terrain, corridors
of wind damage may materialize. Predictability is low this far out,
but categorical risk upgrades appear likely as these periods get
closer in time. The primary risk appears to be damaging winds, but
sporadic large hail is possible with the late afternoon activity.

..Jewell.. 06/11/2025

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ACUS48 KWNS 120835
SWOD48
SPC AC 120833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CDT Thu Jun 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
During the Sunday/D4 to Monday/D5 period, an upper ridge is forecast
to remain over the Plains, with modest southwest flow aloft over the
West. Models suggest that around Tuesday/D6, the upper ridge will
break down over the central/northern Plains, although the amplitude
and track of the wave is in question. Ample low-level moisture will
be in place from the Plains to the East Coast, with mid to upper 60s
F as far north as southern parts of the Great Lakes.

As a result of this large area of moisture and instability, widely
scattered thunderstorms will be common each day. The northern Plains
appears to have the greatest change of organized severe storms
includes MCS/s, but predictability is clearly low at this time with
the uncertain wave. However, it appears that the Tuesday/D6 to
Wednesday/D7 time frame may yield a corridor of organized damaging
wind potential over parts of the northern and central plains to
Midwest, and these trends will continue to be monitored.

..Jewell.. 06/12/2025

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ACUS48 KWNS 180843
SWOD48
SPC AC 180842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Wed Jun 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
...D4/Saturday...
An amplified upper-level pattern will continue into Saturday, with a
prominent ridge extending from the Southeast into the Midwest and
Ohio Valley, and a deep trough over much of the West. Large to
extreme buoyancy will again develop across parts of the
central/northern Plains and Upper Midwest, but the influence of the
ridge will tend to suppress storm development across the warm
sector.

While differing in the details, some extended-range guidance
suggests that an MCS (or at least its remnant MCV) that develops
late on D3/Friday will move across the far northern Great Lakes and
adjacent parts of Ontario on Saturday, and potentially into parts of
the lower Great Lakes by Saturday evening. Should such an evolution
occur, some severe threat could accompany this system, but
predictability for such a scenario at this range is inherently low.

Farther west, there is substantial spread in guidance regarding the
magnitude of low-level moisture and instability across parts of MT
and northern WY into western ND on Saturday. However, if stronger
flow associated with the western trough can impinge upon favorable
instability, then an organized severe threat could evolve during the
afternoon and evening.

...D5/Sunday...
The western trough is generally forecast to take on more of a
positive tilt and eventually deamplify on Sunday, as a substantial
shortwave and midlevel jet maximum eject across parts of the
northern High Plains. As this occurs, a cold front will move across
parts of the northern/central Plains. At this time, it appears the
organized severe threat may be limited by very warm temperatures
aloft and a tendency for stronger deep-layer flow to lag behind the
front.

Strong buoyancy may spread into parts of the Ohio Valley and
Northeast on Sunday. Some organized severe potential could develop
within the instability gradient along the periphery of the ridge,
though mesoscale details remain highly uncertain at this time.

...D6/Monday - D8/Wednesday...
Uncertainty increases into early next week regarding evolution of
the synoptic pattern, though guidance generally suggests that an
upper ridge will remain prominent across parts of the eastern CONUS,
while a weak upper trough will persist across parts of the West into
the northern and central Plains. While some severe potential could
evolve across parts of the Great Plains, Great Lakes, and Northeast
along the periphery of the ridge, details regarding favored days and
locations remain highly uncertain.

..Dean.. 06/18/2025

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ACUS48 KWNS 190847
SWOD48
SPC AC 190845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CDT Thu Jun 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
...D4/Sunday...
The upper-level trough over the West is forecast to take on more of
a positive tilt on Sunday, as an embedded shortwave and attendant
midlevel jet maximum move across the northern Rockies/High Plains.
As this occurs, a surface low is forecast to move from SD toward the
upper Great Lakes, as a trailing cold front moves through the
northern/central Plains. Guidance varies regarding frontal timing,
though generally agrees that stronger mid/upper-level flow will tend
to lag behind the front.

While details remain uncertain, strong to potentially severe storms
may develop near/north of the surface low across parts of the
Dakotas/MN, and also along the trailing cold front into the central
Plains.

...D5/Monday - D8/Thursday...
The upper ridge across the Southeast is expected to remain in place
through at least early next week, with some guidance suggesting
potential for deamplification by the middle of the week. Multiple
shortwaves may emerge from the persistent (though weakening) western
trough through at least Wednesday, resulting in some potential for
strong to severe storms along the periphery of the upper ridge from
the Plains into the upper Midwest and Great Lakes, and possibly
parts of the Northeast. However, predictability remains quite low
regarding the details of any organized severe threats during this
time frame.

..Dean.. 06/19/2025

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