ACUS48 KWNS 200858
SWOD48
SPC AC 200856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Wed May 20 2026

Valid 231200Z - 281200Z

...DISCUSSION...
Severe potential will remain low through the extended period. Weak
troughing will continue across the central Plains through the
weekend before height rises begin across the central US with a high
amplitude ridge settling in from the west. This pattern will remain
in place through early to middle of next week. Slow moisture return
will be ongoing across much of the Plains into the Midwest with
occasional rounds of widespread rainfall and thunderstorms, but
generally weak flow and subsidence will keep organized storm
potential low through D8/Wednesday.

..Thornton.. 05/20/2026

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ACUS48 KWNS 210849
SWOD48
SPC AC 210847

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CDT Thu May 21 2026

Valid 241200Z - 291200Z

...DISCUSSION...
Severe potential will remain low through the beginning of the
extended period. Weak troughing will continue across the central
Plains D4/Sunday before height rises begin across the central US
with a high amplitude ridge settling in from the west D5/Monday.
This pattern will remain in place through early next week. Slow
moisture return will be ongoing across much of the Plains into the
Midwest with occasional rounds of widespread rainfall and
thunderstorms, but generally weak flow and subsidence will keep
organized storm potential low.

By the midweek, a trough is progged to begin deepening across the
Pacific Northwest. As the upper low slowly shifts eastward, stronger
flow will overspread the Intermountain West into the Northern
Rockies, resulting in strengthening lee troughing across the
central/northern Plains D6/Tuesday and D7/Wednesday. Moisture
advection will spread northward amid strengthening southerly flow
across the central/northern Plains. While there are some differences
in the placement of upper-level and surface features, it is possible
that severe chances will return across portions of northern High
Plains. For now, confidence in exact corridors remains low given
model guidance differences.

..Thornton.. 05/21/2026

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ACUS48 KWNS 220903
SWOD48
SPC AC 220901

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0401 AM CDT Fri May 22 2026

Valid 251200Z - 301200Z

...DISCUSSION...
Severe potential will remain low D4/Monday. Height rises begin
across the central US with a high amplitude ridge settling in from
the west. Slow moisture return will be ongoing across much of the
Plains into the Midwest with widely scattered areas of rainfall and thunderstorms. A few strong to marginally severe storms will be
possible, but generally weak flow and subsidence will keep organized
storm potential low.

A trough is progged to begin deepening across the Pacific Northwest
D5/Tuesday into D6/Wednesday. As the upper low slowly shifts
eastward, stronger flow will overspread the Intermountain West into
the Northern Rockies, resulting in strengthening lee troughing
across the central/northern Plains. Moisture advection will spread
northward amid strengthening southerly flow across the
central/northern Plains. There remains uncertainty in the northward
and westward extent of moisture return and in progression of the
western trough. Severe storms may occur each day across some portion
of the northern and northern/central High Plains. For now,
confidence in exact corridors remains low.

By D7/Thursday-D8/Friday, guidance suggests the western low becomes
cut off and slowly wobbles towards the Great Basin before becoming
absorbed back into the northern stream. This is likely due to
continued high amplitude ridging across the central US. Some severe
potential may extend into the eastern US as a cold front shifts
southward as flow enhances in the trough across Quebec in the D7-D8
period.

..Thornton.. 05/22/2026

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ACUS48 KWNS 230855
SWOD48
SPC AC 230853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Sat May 23 2026

Valid 261200Z - 311200Z

...DISCUSSION...
A trough will deepen and shift eastward across the Pacific Northwest D4/Tuesday-D5/Wednesday. As the upper low slowly shifts eastward,
stronger flow will overspread the Intermountain West into the
Northern Rockies which will result in strengthening lee troughing
across the central/northern Plains. Moisture advection will spread
northward with the strengthening southerly flow across the
central/northern Plains. Severe storms may occur each day across
some portion of the northern and northern/central High Plains. In
addition, strengthening southern stream flow may bring stronger
storms across the Sierra Madre which may bring severe potential into
portions of far southern Texas. For now, confidence in exact
corridors of greater severe potential remains low.

By D6/Thursday-D8/Saturday, guidance suggests the western low
becomes cut off and slowly wobbles towards the Great Basin before
becoming absorbed back into the northern stream, likely due to the
high amplitude ridging across the central. Some severe potential may
extend into the eastern US as a cold front shifts southward as flow
enhances in the trough across Quebec in the D6-D7 period.

..Thornton.. 05/23/2026

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ACUS48 KWNS 240902
SWOD48
SPC AC 240900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Sun May 24 2026

Valid 271200Z - 011200Z

...DISCUSSION...
The western US trough will shift southward into the Great Basin on
D4/Wednesday with strengthening westerly flow overspreading the
southwestern US. The axis of the central US ridge will shift
eastward, with heights continuing to rise across portions of the central/northern Plains. A few stronger storms may be possible
across portions of central/eastern Montana. Overall, confidence is
low in any areas of organized severe potential. Widely scattered
thunderstorm activity will be possible from the Southern/Central
Plains to the southeastern US. Generally weak flow should keep
organized severe potential low. The exception may be across far
western Texas where modest mid-level flow will continue, though
large scale forcing for ascent will decrease from D3/Tuesday.

For the D5/Thursday through D6/Friday period, ensemble guidance
suggests the western low will shift northward again and phase with
the northern jet stream. There is low confidence in chances for
strong to severe storms, pending details on moisture, across the
northern Rockies into the central/northern high Plains as lee
troughing strengthens. Some severe potential may also extend into
the eastern and southeastern US as a cold front shifts southward as
flow enhances in the trough across Quebec from D6/Friday to
D7/Saturday.

..Thornton.. 05/24/2026

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ACUS48 KWNS 250845
SWOD48
SPC AC 250843

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0343 AM CDT Mon May 25 2026

Valid 281200Z - 021200Z

...DISCUSSION...
...D4/Thursday through D5/Friday...
The western low is expected to shift northward again and phase with
the northern jet stream D4/Thursday - D5/Friday. There is low
confidence in chances for strong to severe storms, pending details
on moisture, across the Intermountain West and northern Rockies.

Guidance suggests that as the western trough shifts northward and
weak disturbances rotate across the Rockies, lee troughing across
the Plains may strengthen D5/Friday, bringing a potential for low
end severe risk into the central/northern High Plains. For now
confidence in any corridors of organized severe risk remain too low.

A cold front will sag southward across the east coast D4/Thursday
through D5/Friday as enhanced flow digs an upper level trough across
Quebec southward into the eastern Great Lakes. Some low end severe
potential may accompany this frontal passage each day, but
uncertainty remains high in overlap of deep layer shear with better moisture/instability.

...D6/Saturday through D8/Monday...
Toward the end of next weekend D7/Sunday through D8/Monday, ensemble
guidance is increasing in confidence for a large scale ridge to
build in across the central/western US with rising heights and
warming temperatures. Building surface high pressure across the
Midwest/Great Lakes may shunt moisture southward to the Gulf states.
Should this pattern continue to hold, severe potential will remain
low through much of the CONUS.

..Thornton.. 05/25/2026

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ACUS48 KWNS 260840
SWOD48
SPC AC 260838

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CDT Tue May 26 2026

Valid 291200Z - 031200Z

...DISCUSSION...
An upper low is forecast to be located over the Great Basin on
Friday/D4, moving into the northern Rockies/High Plains through
Saturday/D5, and weakening all the while. Models indicate 500 mb
winds by Saturday will only be in the 20-25 kt range with this
feature. Therefore, despite low 60s F dewpoints, the severe risk is
expected to be somewhat disorganized. However, at least low
probabilities may be required in later outlook updates.

Meanwhile, a low-latitude shortwave trough is forecast to move
across the southern Plains and into the lower MS Valley, from
Saturday/D5 into Sunday/D6. Given the expected very moist air mass
in place with 70s F dewpoints, and lack of capping, scattered areas
of thunderstorms are likely throughout the period. Much of the
activity will occur over TX and OK, where moderate instability is
forecast. However, shear will be generally weak. Given the daily
cycle of thunderstorms and resulting outflow boundaries across the
entire region, predictability is too low to denote any concentrated
severe areas. However, sporadic severe winds, perhaps isolated hail,
cannot be ruled out from the southern Plains into the lower MS
Valley from Saturday/D5 into Monday/D7.

..Jewell.. 05/26/2026

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ACUS48 KWNS 270747
SWOD48
SPC AC 270746

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 AM CDT Wed May 27 2026

Valid 301200Z - 041200Z

...DISCUSSION...
On Saturday/D4, an upper low will weaken as it moves from UT into
WY, with midlevel wind speeds at or below 25 kt across the northern Rockies/Plains. This feature will persist into Sunday/D5 and
Monday/D6 as it moves toward MT and eventually into Canada. Given
the weak winds aloft, severe potential should be relatively low, but
isolated strong storms may occur over parts of the northern Plains.

Farther south, stronger instability is forecast over the southern
and central Plains, where 60s to lower 70s F dewpoints will exist.
Although unstable, shear will be quite weak. Saturday/D4 may hold
slightly greater severe potential compared to other days, as the
southern lobe of the western trough lifts north out of the
southern/central Plains. However, shear will still be marginal, and
the likelihood antecedent precip/outflows lessens predictability in
the weak forcing pattern. The stronger instability air mass appear
most prominent through about Monday/D6. Thereafter, an upper trough
may amplify over the eastern CONUS, driving high pressure south
across the eastern CONUS/MS Valley.

..Jewell.. 05/27/2026

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ACUS48 KWNS 280839
SWOD48
SPC AC 280837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Thu May 28 2026

Valid 311200Z - 051200Z

...DISCUSSION...
For much of the D4-D8 period, an upper trough is forecast to reside
over the Northeast, with high pressure over the Great Lakes and much
of the Midwest to Mid Atlantic. West of this surface high, southerly
winds across the Plains will maintain a moist air mass with 60s and
70s F dewpoints prevalent.

In the upper levels, a weak negatively tilted trough will shift
slowly northward across the northern Plains & Rockies on Sunday/D4
and Monday/D5, providing cooler temperatures aloft and slightly
stronger wind speeds. Farther south into the central and southern
Plains, winds aloft will be even weaker, however, the midlevels will
remain relatively cool, supporting areas of strong instability due
to steep lapse rates aloft.

In general, areas of strong thunderstorms appear likely on a daily
basis across much of the Plains during the peak heating hours. Areas
of severe storms will be possible as well due to the widespread
2000+ J/kg MUCAPE, with localized hail & wind potential where
clusters develop. The NE/KS/OK/MO area in particular will be within
the heart of the instability axis, with 3000-4000 J/kg possible.

Predictability is low in this pattern due to lack of large-scale
forcing, and the fact that clusters of storms may persist overnight
as various outflow boundaries affect storm potential each subsequent
day. However, smaller/more focused areas of potential may become
evident in subsequent outlook cycles.

..Jewell.. 05/28/2026

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ACUS48 KWNS 290828
SWOD48
SPC AC 290826

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0326 AM CDT Fri May 29 2026

Valid 011200Z - 061200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
At mid-levels, a ridge is forecast to move from the north-central
U.S. on Monday into the Great Lakes by Wednesday, as a shortwave
trough moves slowly eastward from the northern Rockies into the
northern Plains. In the vicinity of the ridge on Monday, an axis of
moderate to strong instability is forecast to develop. In spite of
limited forcing, isolated severe storms may form on Monday afternoon
over parts of the north-central U.S., mainly in areas where
low-level convergence becomes maximized. On Tuesday, isolated severe
storms will be possible ahead of the approaching trough along a
north-to-south corridor of instability in the Dakotas and Nebraska.
Storms will again be possible ahead of the trough in the upper
Mississippi and mid Missouri Valleys on Wednesday. The primary
threats would be isolated severe gusts and hail.

...Thursday/Day 7 and Friday/Day 8...
The mid-level trough is forecast to move into the Great Lakes on
Thursday and into the Northeast on Friday, as another trough moves
into the central U.S. Ahead of this second trough, isolated severe
storms will be possible on Thursday and Friday in parts of the
central and northern Plains. A few of the stronger storms could be
associated with severe wind gusts and hail.

..Broyles.. 05/29/2026

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ACUS48 KWNS 300844
SWOD48
SPC AC 300842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Sat May 30 2026

Valid 021200Z - 071200Z

...DISCUSSION...
...Tuesday/Day 4 to Thursday/Day 6...
At mid-levels, a ridge is forecast to move slowly eastward from the
upper Mississippi Valley on Tuesday to the northeastern U.S. by
Thursday. During that time, a shortwave trough is forecast to move
slowly eastward across the north-central U.S. Isolated severe
thunderstorms will be possible ahead of the trough each afternoon
and evening. The greatest severe threat is currently expected in the
Dakotas on Tuesday and Wednesday, and in the upper Mississippi
Valley on Thursday. Regarding the spatial extent of any severe
threat, some uncertainty exists concerning the timing of the trough
and the location of maximum instability.

...Friday/Day 7 and Saturday/Day 8...
Multiple shortwave troughs are forecast to move across the central
U.S. on Friday and Saturday. During this time, moisture and
instability is forecast to be maximized in the Great Plains. As
surface temperatures heat up each day, thunderstorm development and
potentially an isolated severe threat will be possible across a
relatively broad moist sector. Concerning predictability, the
convoluted pattern introduces considerable uncertainty as to where
the greatest severe threat will be.

..Broyles.. 05/30/2026

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ACUS48 KWNS 310844
SWOD48
SPC AC 310842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Sun May 31 2026

Valid 031200Z - 081200Z

...DISCUSSION...
...Wednesday/Day 4 to Friday/Day 6...
A mid-level trough is forecast to move into the northern High Plains
on Wednesday, into the upper Mississippi Valley on Thursday and into
the Great Lakes on Friday. A moist and unstable airmass is forecast
over the northern Plains, where a severe threat will be possible
during the afternoon and evening on both Wednesday and Thursday.
Large hail and severe wind gusts would be possible. The threat is
forecast to be concentrated ahead of a cold front passing through
the northern Plains. Considerable uncertainty exists concerning the
timing of the front.

In the wake of the trough, a shortwave ridge is forecast to move
into the northern Plains on Friday. Isolated severe storms will
again be possible across the Dakotas Friday afternoon within an
unstable airmass, but limited forcing would keep any severe threat
more localized.

Further south across the southern and central Plains, a relatively
broad corridor of moderate instability is forecast each afternoon
from Wednesday to Friday. However, forcing is expected to remain
limited, which should keep any severe threat isolated and
conditional.

...Saturday/Day 7 and Sunday/Day 8...
On Saturday and Sunday, a mid-level trough is forecast to move
eastward into the northwestern U.S., as a shortwave ridge moves from
the Great Plains into the Mississippi Valley. In the wake of the
ridge, a secondary trough is forecast to move through the southern
and central Plains. Isolated severe storms would be possible near
this trough in the afternoon and evening on both Saturday and
Sunday. However, the timing of the trough and distribution of
instability surrounding the trough is considerably uncertain at this
time.

..Broyles.. 05/31/2026

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ACUS48 KWNS 010857
SWOD48
SPC AC 010855

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CDT Mon Jun 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
At mid-levels, a trough is forecast to move across the western U.S.
on Thursday, as a subtle lead shortwave trough moves into the
central and northern High Plains. At the surface, a broad area of
moderate instability is forecast to be in place across much of
Nebraska and South Dakota by afternoon. Scattered thunderstorms are
expected to develop ahead of the shortwave trough in the central and
northern High Plains, with these storms moving eastward across
western Nebraska and western South Dakota during the afternoon and
evening. The instability along with moderate to strong deep-layer
shear is expected to support severe thunderstorm development.
Supercells with large hail and severe wind gusts will be possible.
An isolated tornado threat may also develop.

The mid-level shortwave trough is forecast to move eastward across
the northern Plains on Friday and into the upper Mississippi Valley
on Saturday. During this time, a severe threat will be possible each
afternoon ahead of the shortwave trough in a moist and unstable
airmass. A more isolated severe threat may develop southward into
the central Plains and lower to mid Missouri Valley. For these two
days, spatial uncertainty is substantial concerning the exact
location of where the severe threat will be greatest.

...Sunday/Day 7 and Monday/Day 8...
From Sunday into Monday, a broad corridor of moist air is expected
to be in place over the Great Plains. Moderate to strong instability
appears likely to develop across parts of this airmass each
afternoon. Model forecasts suggest that deep-layer shear will remain
relatively weak over most of the Great Plains. Although an isolated
severe threat would be possible in some areas, uncertainty
concerning the mid-level pattern and the resultant deep-layer shear
is considerable at this time.

..Broyles.. 06/01/2026

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ACUS48 KWNS 020914
SWOD48
SPC AC 020913

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0413 AM CDT Tue Jun 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
...Day 4/Friday...

The 00z ensemble mean solutions are in reasonable agreement in the
eastward progression of a low-amplitude short-wave trough through
the northern and central Plains into the upper Midwest, in tandem
with a surface front. Those features are expected to support
diurnally enhanced thunderstorm development, especially from parts
of the mid MO Valley into upper Midwest amidst a moist and
moderately unstable air mass. However, there is model spread in the
strength of vertical shear across the warm sector, which casts
uncertainty on organized severe-weather potential.


...Days 5/Saturday and 6/Sunday...

A vigorous short-wave trough moving onto the Pacific Northwest and
BC coasts Saturday morning is forecast to weak while lifting
northeast into the lee of the Canadian Rockies. A belt of enhanced
mid-level winds attending that system is forecast to overspread the
northern Rockies Saturday, and then the adjacent northern High
Plains on Sunday. The 00z EPS/GEFS/CMCE ensembles indicate
clustering in lee cyclone development across WY or MT on Saturday,
with considerably more spread in surface low positions by Sunday.
However, those data do suggest that a front will move into the
northern High Plains during the day Sunday.

Isolated severe storms appear possible across portions of central
and eastern MT Saturday, and perhaps portions of MT into ND on
Sunday. Low predictability will be maintained in these areas as it
appears that the better forcing for ascent may tend to spread north
into Canada. However, these areas will be monitored for a potential
upgrade to a 15% unconditional severe-weather probability in
subsequent outlooks.

Elsewhere, there is reasonable model agreement in a mid-level trough
moving through the Great Lakes and Northeast, with a lower-latitude
system lifting north through the southern and central Plains. The
presence of a moist and unstable air mass will support strong to
isolated severe-storm potential from parts of the southern and
central Plains into Great Lakes on Saturday, and southern and
central Plains into Ozark Plateau and Mid-Atlantic States on Sunday.


...Days 7/Monday and 8/Tuesday...

The various ensemble mean solutions indicate some longitudinal
variance in an evolving mid-level trough in the vicinity of the
Pacific Coast. Elsewhere, the southern/central Plains trough
discussed in the previous section is forecast to weaken while
progressing into the upper Midwest. In general, these solutions
indicate the strongest mid-level flow confined to the Interior West,
and across Canada. The models suggest the most probable overlap of
that higher-momentum flow (and associated vertical shear) with a
moist and unstable air mass is from the northern Rockies into
northern High Plains during this time frame, supporting some
severe-storm threat.

.... 06/02/2026

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ACUS48 KWNS 021035
SWOD48
SPC AC 021033

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0533 AM CDT Tue Jun 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
...Day 4/Friday...

The 00z ensemble mean solutions are in reasonable agreement in the
eastward progression of a low-amplitude short-wave trough through
the northern and central Plains into the upper Midwest, in tandem
with a surface front. Those features are expected to support
diurnally enhanced thunderstorm development, especially from parts
of the mid MO Valley into upper Midwest amidst a moist and
moderately unstable air mass. However, there is model spread in the
strength of vertical shear across the warm sector, which casts
uncertainty on organized severe-weather potential.


...Days 5/Saturday and 6/Sunday...

A vigorous short-wave trough moving onto the Pacific Northwest and
BC coasts Saturday morning is forecast to weak while lifting
northeast into the lee of the Canadian Rockies. A belt of enhanced
mid-level winds attending that system is forecast to overspread the
northern Rockies Saturday, and then the adjacent northern High
Plains on Sunday. The 00z EPS/GEFS/CMCE ensembles indicate
clustering in lee cyclone development across WY or MT on Saturday,
with considerably more spread in surface low positions by Sunday.
However, those data do suggest that a front will move into the
northern High Plains during the day Sunday.

Isolated severe storms appear possible across portions of central
and eastern MT Saturday, and perhaps portions of MT into ND on
Sunday. Low predictability will be maintained in these areas as it
appears that the better forcing for ascent may tend to spread north
into Canada. However, these areas will be monitored for a potential
upgrade to a 15% unconditional severe-weather probability in
subsequent outlooks.

Elsewhere, there is reasonable model agreement in a mid-level trough
moving through the Great Lakes and Northeast, with a lower-latitude
system lifting north through the southern and central Plains. The
presence of a moist and unstable air mass will support strong to
isolated severe-storm potential from parts of the southern and
central Plains into Great Lakes on Saturday, and southern and
central Plains into Ozark Plateau and Mid-Atlantic States on Sunday.


...Days 7/Monday and 8/Tuesday...

The various ensemble mean solutions indicate some longitudinal
variance in an evolving mid-level trough in the vicinity of the
Pacific Coast. Elsewhere, the southern/central Plains trough
discussed in the previous section is forecast to weaken while
progressing into the upper Midwest. In general, these solutions
indicate the strongest mid-level flow confined to the Interior West,
and across Canada. The models suggest the most probable overlap of
that higher-momentum flow (and associated vertical shear) with a
moist and unstable air mass is from the northern Rockies into
northern High Plains during this time frame, supporting some
severe-storm threat.

..Mead.. 06/02/2026

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ACUS48 KWNS 030846
SWOD48
SPC AC 030845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CDT Wed Jun 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
...Day 4/Saturday...

Model guidance is in good agreement in the progression of a
short-wave trough from the Great Lakes into Northeast, with a strong
upstream system moving through the Canada Rockies and Pacific
Northwest into the northern Rockies. Elsewhere, a mid-level low will
track through the southern and central Plains. In the low levels, a
cold front is forecast to move through the Great Lakes into the OH
Valley and Northeast, while a lee cyclone deepens over the northern
High Plains along a separate cold front emerging from the northern
Rockies.

The most probable location for organized severe thunderstorm
development appears to be in the vicinity of the lee cyclone and
front in portions of eastern MT and western ND Saturday afternoon
and evening. There, steep lapse rates and moderate instability will
coincide with steadily strengthening deep-layer shear. Elsewhere, at
least isolated severe storms appear possible along the cold front
from portions of the Great Lakes into the OH Valley and the
Northeast, as well as in parts of TX, to the southeast of the upper
low.


...Day5/Sunday...

A short-wave trough will continue through the Northeast and
Mid-Atlantic, while the bulk of ensemble guidance suggests the
northern Rockies disturbance will lift northeast into the Canadian
Prairie Provinces. Meanwhile, the central/southern Plains low is
forecast to evolve into an open wave while moving into the mid/lower
MO Valley and Ozark Plateau. The models indicate the potential for
moderate to strong instability to develop across the northern Plains
warm sector on Sunday afternoon. However, there is some signal that
the strongest vertical shear will be displaced to the west of the
cold front. Furthermore, given that the strongest forcing for ascent
is expected to lift north of the International Border, residual
capping across the warm sector may limit storm coverage. Given these
concerns, no probabilities will be included in this forecast.

Elsewhere, at least isolated severe storms appears possible along
the cold front in portions of the Northeast into Mid-Atlantic Sunday
afternoon.


...Day 6-8/Monday through Wednesday...

Ensemble guidance is suggestive that mid-level troughing will evolve
along the West Coast early next week, with that feature slowly
advancing through the Interior West. Considerably more spread is
evident in the deterministic models, with low confidence in any one
solution. In general, it appears that the stronger mid-level flow
associated with the western U.S. trough may begin to overspread
portions of the northern and central High Plains by Tuesday and/or
Wednesday, where a moist and unstable air mass is expected to
reside. Should confidence increase in the finer-scale details of the
pattern, unconditional 15% probabilities may need to be included
during this time frame.

..Mead.. 06/03/2026

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