SPC AC 051245
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Sun Jul 05 2026
Valid 051300Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE MID-ATLANTIC...NORTHERN NORTH DAKOTA...AND NORTHWEST/WEST
TEXAS...
...SUMMARY...
Scattered wind damage is possible with thunderstorms across the
Mid-Atlantic this afternoon and evening. Large to very large hail
and damaging gusts may occur with thunderstorms in North Dakota with
occurrences of hail and damaging winds possible from west into
northwest Texas as well.
...Upper Ohio Valley into Mid-Atlantic and Carolina Piedmont...
Early morning surface analysis places a low over northwest OH, along
a diffuse west to east oriented cold front extending from IA through
PA and NJ. Expectation is for this low to gradually shift eastward
just ahead of slow-moving shortwave trough. Thunderstorm development
is anticipated in the vicinity of this low as well as along the cold
front, forced predominantly by low-level convergence, across the
Upper OH Valley. Lapse rates will be poor, but warm and moist
surface conditions will still support modest buoyancy and the
potential for strong updrafts. Vertical shear is weak so storm
organization will be limited, but a few bowing segments are still
possible given the potential for strong cold pools. Highest
likelihood for a few stronger gusts will be across eastern PA and NJ
where slightly stronger mid-level flow exists.
Modest lee troughing is expected from central MD southwestward
through the Carolina Piedmont. Diurnal airmass destabilization is
anticipated in the vicinity of this troughing, supported by very
warm and moist conditions (i.e. temperatures in the upper 90s and
dewpoints in the upper 60s/low 70s). Afternoon thunderstorms are
expected along this troughing, with moderate to strong buoyancy
(i.e. MLCAPE from 1500 to 2500 J/kg) supporting strong updrafts and
potential water loading. Vertical shear will be weak, so the
expectation is for outflow-dominant multicell storms to merge into
clusters or line segments. The hot, well-mixed PBL and resultant,
steep low-level lapse rates will enhance the damaging wind potential
from mid afternoon into evening. Damaging wind potential is expected
to be more sporadic with southward extent into the Carolinas owing
to more limited storm coverage.
...Northern Rockies into the Northern Plains...
Steep mid-level lapse rates are forecast to spread
eastward/northeastward from the northern Rockies into the northern
Plains, ahead of a shortwave trough progressing through southern
British Columbia and Alberta. The boundary layer will be relatively
warm and modestly dry, but, given the steep mid-level lapse rates in
place, airmass destabilization is still anticipated. Height falls
associated with the shortwave will augment convergence along a cold
front to provide the lift needed for thunderstorm development in
western ND after the airmass destabilizes. There should be enough
vertical shear in place to support organized storm structures
capable of large hail and damaging gusts.
Thunderstorm development also appears possible farther west across
MT closer to the shortwave trough. These storms are expected to be
high based atop a well-mixed boundary layer with severe wind gusts
being the predominant hazard.
...Southern High Plains into east TX...
An outflow boundary from the overnight storms in OK currently arcs
from east-central TX (near LFK) northwestward to near MWL and into
west TX where it intersects a low east of LUB. Thunderstorm
development appears likely along this boundary once the airmass
diurnally destabilizes this afternoon. Highest coverage is
anticipated from west into northwest TX, with more isolated to
widely scattered coverage expected farther east. Vertical shear will
be weak, resulting in an outflow-dominant storm structure. High
storm bases and a deeply mixed boundary layer should result in
strong cold pools across west/northwest TX, with cold pool
amalgamation perhaps resulting a greater potential for damaging
gusts than farther east.
...Lower MS Valley into AL...
A very moist airmass will support diurnal destabilization and
moderate to strong buoyancy this afternoon from the Lower MS Valley
eastward into AL. Remnant MCS and associated vorticity maximum
currently moving across northern LA are forecast to continue
eastward/southeastward, with a second, smaller convective cluster
also continuing across northern/central AL. These features will
interact with the moist and unstable airmass this afternoon,
supporting thunderstorm development. Vertical shear will be weak and
a predominantly outflow-dominant multicellular mode is anticipated.
Some stronger gusts are possible via water-loaded downbursts and/or
occasional bowing segments.
..Mosier/Dean.. 07/05/2026
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
SPC AC 050443
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1143 PM CDT Sat Jul 04 2026
Valid 061200Z - 071200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS MONDAY INTO
MONDAY EVENING ACROSS PARTS OF THE CENTRAL AND EASTERN DAKOTAS
THROUGH NORTHERN MINNESOTA AND ACROSS PARTS OF THE MID ATLANTIC...
...SUMMARY...
Strong thunderstorm development posing at least some risk for severe
weather is possible across parts of northern Minnesota through the
eastern and central Dakotas, as well as across parts of the Mid
Atlantic, Monday afternoon into evening.
...Discussion...
Downstream of digging large-scale mid-level troughing and an
associated surface cyclone slowly approaching the British Columbia
and Pacific Northwest coast, ridging may become increasingly
prominent across Baja California through the southern Rockies and
central Great Plains during this period. Mid-level heights may tend
to remain steady or slowly rise as far north as the eastern
Montana/North Dakota international border, in the wake of a notable
mid-level trough forecast to progress through northwestern Ontario
and Hudson Bay by late Monday night.
It appears that one vigorous impulse embedded within the troughing,
and forecast to continue accelerating east-northeastward, to the
north of the international border, may provide support for stronger
secondary surface cyclogenesis across the southern Hudson Bay
vicinity by Monday night.
To the east of the mid-level ridging, weak mid-level troughing may
continue to drift slowly east of the Mississippi Valley, toward the
Appalachians.
In association with this evolving regime, the potential for
organized severe thunderstorm activity still appears generally low
and dependent on sub-synoptic developments with rather low
predictability at this time frame. This continues to be reflected
in latest model output, including convection allowing and related
guidance, which exhibit sizable spread concerning potential
convective evolution and locations with higher probabilities for
thunderstorm development.
...Northern Great Plains...
Deeper surface troughing and mid-level height falls are forecast to
pass to the north of the international border through this period.
However, there appears at least some continuing signal in model
output that boundary-layer moisture return to the vicinity of weak
pre-frontal surface troughing, coincident with southeastward
suppression of warmer and more strongly capping elevated mixed-layer
air, could allow for scattered strong thunderstorm development by
late Monday afternoon. If this occurs, moderate to large potential
instability, in the presence of at least modest shear beneath 30-40
kt 500 mb flow, probably will be conducive to storms capable of
producing severe hail and wind, before perhaps tending to be
undercut by a southward advancing cold front trailing the developing
Canadian cyclone.
...Mid Atlantic...
The timing and/or location of highest thunderstorm probabilities
across the region differs notably between the REFS and HREF
calibrated thunderstorm guidance, and deep-layer mean flow and shear
will be rather weak. However, destabilization within broad, weak
surface troughing to the lee of the Blue Ridge might become
sufficient to focus scattered thunderstorm development with
potential to produce localized damaging surface gusts Monday
afternoon into early evening.
..Kerr.. 07/05/2026
WUUS02 PTSDY2
SPC AC 050726
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 AM CDT Sun Jul 05 2026
Valid 071200Z - 081200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE TUESDAY
THROUGH TUESDAY NIGHT ACROSS PARTS OF CENTRAL AND EASTERN SOUTH
DAKOTA INTO SOUTHWESTERN MINNESOTA...
...SUMMARY...
An organizing cluster of thunderstorms may pose increasing potential
to produce strong to severe wind gusts by late Tuesday evening into
Tuesday night across parts of the middle Missouri Valley toward the
Upper Midwest.
...Discussion...
Models suggest that the westerlies may become a bit less progressive
across the higher latitudes of North America during this period,
with a deep remnant lower/mid-tropospheric cyclone only slowly
migrating east-northeastward across Hudson Bay toward the northern
Quebec shores. Upstream, a notable trough is forecast to only
slowly pivot inland of the British Columbia coast.
In advance of the trailing perturbation, a low-amplitude trough
within modest zonal westerlies across the northern tier of the U.S.
is forecast to progress east of the northern Rockies, and flatten
initial mid-level ridging across the middle Missouri Valley by late
Tuesday night.
Otherwise, mid-level ridging is forecast to remain prominent along
an axis from the subtropical eastern Pacific through the central and
southern Great Plains, while also developing northwestward from the
subtropical western Atlantic into parts of the southeast. A remnant
trough or shear axis will likely linger in between, near/west
through southwest of the southern Appalachians.
...Parts of the middle Missouri Valley into Upper Midwest...
Latest guidance suggests that potential for stronger convective
development may still remain largely influenced by sub-synoptic
developments with rather low predictability at this time frame.
However, there appears a consistent enough developing convective
signal among the various model output to lead to some confidence in
the evolution of an organized convective system across the mid
Missouri Valley vicinity by late Tuesday night.
It appears that stronger pre-frontal daytime heating may focus
moderate to strong destabilization in a corridor roughly across
south central South Dakota toward southwestern Minnesota by late
Tuesday afternoon. Beneath steep lapse rates, surface dew point
increases to around 70F may support mixed-layer CAPE on the order of
2000-3000+ J/kg.
As remnant warm elevated mixed-layer air is suppressed further
southward, the initiation of storms capable of producing severe
hail and wind seems probable by early Tuesday evening. It is
possible that the most substantive upscale growth, intensification
and organization awaits forcing associated with a nocturnal
strengthening low-level jet toward late evening. But, as this
occurs, the environment appears potentially conducive to the
development of a swath of damaging winds as it propagates
east-southeastward Tuesday night.
..Kerr.. 07/05/2026
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 1930Z
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