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DAY2 2/5 Risk Area Posted
From
Mike Powell@618:250/6 to
All on Mon Apr 27 08:25:22 2026
ACUS02 KWNS 270533
SWODY2
SPC AC 270531
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1231 AM CDT Mon Apr 27 2026
Valid 281200Z - 291200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TUESDAY AFTERNOON
AND EVENING IN A CORRIDOR ACROSS THE SOUTHEASTERN GREAT PLAINS
THROUGH LOWER MISSISSIPPI AND TENNESSEE VALLEYS...
...SUMMARY...
Scattered strong to severe thunderstorm development is probable
across parts of the southeastern Great Plains through the lower
Mississippi and Tennessee Valleys Tuesday afternoon and evening.
The evolution of a long-lived organized cluster accompanied by
potentially damaging wind gusts appears possible.
...Discussion...
Latest model output still indicates that the center of a fairly
broad surface cyclone may undergo further deepening while migrating
northeast of the upper Great Lakes region during this period,
particularly as it reaches the southeastern Hudson Bay vicinity,
near the southeastern periphery of an evolving mid-level low.
Surrounding this low, it appears that larger-scale mid-level
troughing, encompassing much of interior North America to the east
of the northern Rockies, may make slow further progress toward the
northern/mid Atlantic Seaboard, while perhaps undergoing some
amplification along an axis southward through the upper and middle
Mississippi Valley by late Tuesday night. This may support modest
surface wave development along a stalling cold front across the
southeastern Great Plains through lower Ohio Valley, and contribute
to suppression of mid-level ridging across northern portions of the
eastern Gulf Coast states.
Otherwise, mid-level ridging to the north of a prominent subtropical
high, still centered over southern Mexico, is likely to build across
the southern Rockies and adjacent Great Plains, downstream of a low
over the southern mid- to subtropical latitudes of the eastern
Pacific. Only a slow eastward progression of this low is forecast,
to the south of mid/upper ridging building northeastward into
British Columbia and the Pacific Northwest.
...Southeastern Great Plains into Tennessee Valley...
There is continuing spread within the latest model output, but a
consensus of guidance suggests that pre-cold frontal outflow,
generated by convection today through tonight, will remain a notable
feature into and through this period. It appears that the leading
edge of this air mass may curve from parts of the southern Appalachians/Tennessee Valley toward the Ark-La-Tex at 12Z Tuesday.
The extent to which this advances southward through the eastern Gulf
Coast states on its eastern flank, while retreating northeastward
through the lower Mississippi Valley on its western flank, remains
unclear. However, it seems probable that it will become a focus for intensifying thunderstorm development by late Tuesday afternoon in
response to boundary-layer destabilization along and to its south,
and forcing for ascent aided by low-level warm advection.
At the same time, a corridor of stronger pre-frontal surface heating
across parts of northeastern Texas through north central Arkansas
may become the focus for stronger convective development, in the
presence of larger CAPE supported by steeper mid-level lapse rates.
More strongly capping elevated mixed-layer air may continue to
inhibit more than isolated thunderstorm initiation farther to
southwest, along the dryline across central Texas into areas
near/south of Del Rio TX.
Strengthening shear with the approach of digging mid-level troughing
on the southern fringe of the westerlies is likely provide support
for a few supercells across the southeastern Great Plains, and
upscale growing and organizing clusters propagating into the lower
Mississippi Valley. There appears a consensus within the model
output that the intersection of this activity with the preceding
outflow boundary may ultimately provide the focus for the most
prominent evolving cluster, which may pose a risk for widespread
strong to severe gusts across parts of Arkansas through the lower
Mississippi Valley by late Tuesday evening.
Too many uncertainties exist to upgrade the categorical severe
threat at this time, but this remains possible in later outlooks for
this period.
..Kerr.. 04/27/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/6 to
All on Fri May 1 08:43:54 2026
ACUS02 KWNS 010501
SWODY2
SPC AC 010500
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1200 AM CDT Fri May 01 2026
Valid 021200Z - 031200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS FAR
SOUTHERN GEORGIA INTO NORTH-CENTRAL FLORIDA...
...SUMMARY...
Strong to severe storms are possible across southern Georgia into northern/central Florida Saturday morning into early evening.
...FL vicinity...
An upper trough over the MS Valley vicinity will pivot east across
the Southeast on Saturday. Strong deep-layer west/southwesterly flow
associated with this system will overspread the region. Deep-layer
flow will weaken with southward extent across the FL Peninsula
during the afternoon, but 850-500 mb southwesterly flow is forecast
to remain robust across southern GA into northern/central FL for
much of the day. At the surface, a cold front will be oriented
across the NC/SC coastal plain, extending southwestward to near the
FL/GA line and offshore across the north-central Gulf. Ahead of the
front, a seasonally moist airmass will be in place.
Convection will likely be ongoing in the vicinity of the cold front
Saturday morning. Current CAMs guidance varies with regard to storm
mode and intensity early in the period, with the 00z HRRR being a
notable outlier showing a small but well organized bowing MCS across
the eastern FL Panhandle and southwest GA. Most of the rest of the
CAMs guidance trends toward thunderstorm clusters. The low-level jet
will be favorable for organized convection, and an organized linear
system is possible, but uncertain. Downstream from early-period
convection, upper 60s to near 70 F dewpoints will aid in modest destabilization. Where stronger heating can occur MLCAPE may
increase to around 1000-1500 J/kg. Deep-layer flow will remain
parallel to the surface boundary, so some potential for undercutting
convection by the front is possible. Nevertheless, given the
strength of deep layer flow and strong vertical shear amid
sufficient instability, severe storms posing a risk for damaging
wind gusts is possible. If any more discrete convection can develop,
isolated hail is also possible. The tornado risk is less certain
given a weakening low-level jet with time, questions regarding storm
mode, and overall uncertainty in low-level destabilization.
..Leitman.. 05/01/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/6 to
All on Mon May 4 10:05:20 2026
ACUS02 KWNS 040535
SWODY2
SPC AC 040533
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1233 AM CDT Mon May 04 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTHEAST TEXAS...SOUTHEAST OKLAHOMA...ARKANSAS...AND SOUTHEAST MISSOURI...
...SUMMARY...
Isolated to scattered strong to severe storms are possible Tuesday
afternoon and evening across portions of eastern Oklahoma and
northeast Texas into the Mid-South. Additional strong storms are
possible across parts of the Northeast.
...Synopsis...
Upper troughing centered on the north-central U.S. will phase with
an upper shortwave trough over the Southwest on Tuesday. As this
occurs, strong deep-layer west/southwesterly flow will develop
across the southern Plains to the Ohio Valley and into the
Northeast. At the surface, a cold front is forecast to extend from
southern Lower MI to a surface low over central OK. A dryline will
extend southwestward from the central OK low into central/southwest
TX. The cold front is expected to develop east/southeast through the
period, becoming oriented from the Northeast to southern AR and
northern TX by Wednesday morning. Two areas of severe potential are
expected to be focused ahead of the surface cold front, one across
parts of the southern Plains to the Mid-South and the second across
the Northeast.
...Southern Plains to the Mid-South...
Southerly low-level flow will transport 60s F dewpoints northward to
the east of the surface dryline and as far north as the MO Bootheel
vicinity. Some morning convection or cloud cover is expected across
parts of southern MO toward the MO/OH River confluence. Persistent
warm advection may result in scattered cloudiness across much of the
ArkLaTex and Ozarks vicinity as well. Nevertheless, modest cooling
aloft by late afternoon will aid in steepening midlevel lapse rates
atop the moist boundary layer, supporting MLCAPE in the 1000-2000
J/kg range. Instability will decrease with northeast extent into the
Mid-South. Scattered thunderstorm development is expected by late
afternoon ahead of the surface cold front. Convection may tend to
become linear more quickly across the Mid-South where shear vectors
are parallel to the surface boundary. Further south across parts of
AR into northeast TX closer to the surface triple point, low-level
flow may be less veered and shear vectors supporting initially
discrete cells. Any convection that can remain
semi-discrete/cellular will pose a risk for large hail, strong wind
gusts, and a tornado or two. With time, convection will evolve into
linear segments as a low-level jet increases and the front begins to
develop southeastward.
The risk is more conditional along the dryline with southwestward
extent across TX. Forcing for ascent will be weaker across this area
and the main initiation mechanism will be mixing/dryline
circulations. If storms can develop, hail and strong gusts will be possible.
...Northeast...
A shortwave upper trough over the Great Lakes will develop
east/northeast across Ontario and Quebec through the evening. Strong
deep-layer southwesterly flow will overspread the Northeast as this
occurs. Boundary layer moisture will be modest, with dewpoints
generally in the 40s to low 50s. However, cold temperatures aloft
will foster steep midlevel lapse rates, supporting modest
destabilization during the afternoon/evening (generally less than
1000 J/kg MLCAPE). Increasing large-scale ascent and the approach of
the surface boundary will result in isolated to scattered
thunderstorm development. Strong gusts will be the main risk with
storms given the strength of deep-layer flow and a well mixed
boundary layer. However, isolated hail also will be possible given
35+ kt effective shear and 500 mb temperatures near -18 C.
..Leitman.. 05/04/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/6 to
All on Tue May 5 09:00:34 2026
ACUS02 KWNS 050509
SWODY2
SPC AC 050507
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1207 AM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST TX
TO THE LOWER MS AND TN VALLEYS...
...SUMMARY...
Scattered strong to severe thunderstorms are expected Wednesday
afternoon and evening across portions of Texas into the lower
Mississippi and Tennessee Valleys/southern Appalachians. Damaging
winds, large hail, and a couple of tornadoes will be possible.
...Synopsis...
A positive-tilt large-scale upper trough will extend from the Upper
Great Lakes to the Southwest early Wednesday. The southern extent of
the trough will develop east toward the southern High Plains to
northwest Mexico by Thursday morning. Strong mid/upper southwesterly
flow ahead of the trough will overspread much of the southern and
eastern U.S. At the surface, a cold front will extend from the upper
Ohio Valley to central TX during the morning. The front is expected
to develop south/southeast through the period, becoming oriented
from the southern Mid-Atlantic to South TX by Thursday morning.
Ahead of the front, rich Gulf moisture will be in place across TX
into the Lower MS and TN Valleys, decreasing with northeast extent
into parts of the southern Appalachians.
...Northern TN Valley and southern Appalachians...
Forecast guidance varies, but some showers/thunderstorms may be
ongoing Wednesday morning across parts of AR into northern parts of
the TN Valley within a warm advection regime on the nose a gradually
weakening low-level jet. This activity will likely play some role in destabilization later in the day across parts of the TN Valley into
the southern Appalachians vicinity. Nevertheless, strong deep-layer
shear and a moist boundary layer will be sufficient for at least
some severe risk, including damaging wind gusts and perhaps hail.
Some tornado risk could also materialize given favorable low-level
shear and 0-1 km SRH increasing to greater than 250 m2/s2 during the afternoon/evening. However, this is less certain given
aforementioned instability issues and later storm timing into the
southern Appalachians.
...TX to MS/AL...
Further south from northeast TX into MS/AL, strong destabilization
is forecast where deep boundary layer moisture and stronger daytime
heating occurs. MLCAPE in the 2000-3000 J/kg range appear possible
in particular across northern LA into MS. Midlevel southwesterly
flow is expected to increase by late afternoon into the evening as
early capping will be overcome as the surface front begins to
develop south/southeast. Convection along the cold front may quickly
transition to linear/bowing segments given deep shear parallel to
the surface boundary. However, low-level flow in latest model
guidance does not appear to be overly veered, especially near
northern LA into MS. Forecast hodographs indicate enlarged,
favorably curved hodographs across this area. If open warm sector
supercells develop, a risk for tornadoes (perhaps a couple strong
tornadoes) will be possible. Furthermore, steepening midlevel lapse
rates are evident in forecast soundings, along with
elongated/straight hodographs and 45+ kt effective shear magnitudes.
This indicates any semi-discrete supercells could pose a risk for
large to very large hail. With time during the evening/nighttime
hours, convection should generally congeal into a line or bowing MCS
and spread eastward across the TN Valley toward the southern
Appalachians, posing a risk for damaging gusts. Higher tornado and
hail probabilities were considered across parts of the Lower MS
Valley, however, given uncertainty in storm mode and coverage of
discrete supercells, will hold at level 2 (Slight) risk for now.
Across portions of central TX overnight, some guidance suggests
convection may develop within low-level warm advection as the
western extent of the surface cold front dives southward across the
Edward Plateau vicinity. If storms develop, they would likely be
elevated. Nevertheless, a hail risk could materialize within the
conditional scenario late in the forecast period.
..Leitman.. 05/05/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/10 to
All on Fri May 8 08:09:35 2026
ACUS02 KWNS 080603
SWODY2
SPC AC 080601
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0101 AM CDT Fri May 08 2026
Valid 091200Z - 101200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN OKLAHOMA AND NORTHWEST TEXAS...
...SUMMARY...
Thunderstorms with large hail and a few damaging wind gusts are
expected to develop across parts of the southern Plains Saturday
afternoon and evening. A marginal severe threat is forecast along
parts of the Gulf Coast.
...Southern Plains...
At mid-levels, cyclonically-oriented northwest flow will be in place
over the central U.S. on Saturday. Within the flow, a subtle
shortwave trough is forecast to move into the southern Plains by
early Saturday evening. Ahead of the approaching trough, low-level
moisture advection is forecast ahead of a cold front moving through
the central Plains. A dryline should be located near a triple point
and surface low extending southward into northwest Texas. By late
afternoon, surface dewpoints should be in the 60s F across most of
Oklahoma and north Texas with moderate instability in place.
Low-level convergence will likely become maximized near the triple
point in southwest Kansas and far northwestern Oklahoma, which
should enable convective initiation. Multiple storms are expected to
develop and move south-southeastward across western Oklahoma and
northwest Texas.
The most favorable environment for severe storms is forecast over
southwest Oklahoma during the late afternoon and early evening. RAP
forecasts soundings at 00Z east of the dryline near Altus have 0-6
km shear in the 35 to 40 knot range with 700-500 mb lapse rates
around 7.5 C/km. This suggests that supercell development with large
hail will be possible. At the surface, temperature-dewpoint spreads
are forecast to be around 25 degrees F. This will result in
high-based storms capable of isolated severe wind gusts. The severe
threat could persist into the early to mid evening, as convection
moves south-southeastward into northwest Texas.
...Gulf Coast Region...
West-southwest flow at mid-levels is expected on Saturday along the
Gulf Coast. A shortwave trough is forecast to move through south
Texas Saturday afternoon and into the Gulf Saturday evening. Another
shortwave trough is forecast to move eastward across the Southeast. Warm-advection related storms are forecast to move southeastward
from southern Mississippi and southern Georgia into northern Florida
during the day. These storms could be associated with a marginal
wind-damage threat. Further west across the central and western Gulf
Coast, onshore flow should result in convection along coastal
convergence boundaries during the afternoon. Moderate instability
and sufficient deep-layer shear is forecast for isolated severe wind
gusts and hail.
..Broyles.. 05/08/2026
$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/10)
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From
Mike Powell@618:250/10 to
All on Wed May 13 08:49:28 2026
ACUS02 KWNS 130600
SWODY2
SPC AC 130559
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Wed May 13 2026
Valid 141200Z - 151200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL AND EASTERN KANSAS...
...SUMMARY...
Thunderstorms with large hail and severe wind gusts are expected on
Thursday across parts of central and eastern Kansas, with more
isolated severe storms possible over parts of the lower Missouri
Valley, northern Ozarks and southern High Plains.
...Central Plains/Lower Missouri Valley/Northern Ozarks...
A mid-level shortwave ridge will move into the upper Mississippi
Valley and Ozarks on Thursday, as a subtle shortwave trough moves
into the Great Plains. Ahead of the trough, low-level moisture
advection will increase surface dewpoints into the 60s F over much
of the eastern half of Kansas. During the day, the airmass will
become moderately unstable as surface temperatures warm. In the
afternoon, low-level convergence will increase along a dryline in
southern and central Kansas supporting scattered thunderstorm
development. A few storms are expected to increase in intensity and
move eastward across central and eastern Kansas during the late
afternoon and early evening. MLCAPE in the 1000 to 2000 J/kg range,
0-6 km shear around 40 knots and 700-500 mb lapse rate near 8 C/km
will be favorable for supercells with large hail. Hailstones of
greater than 2 inches in diameter may occur with any supercell that
can become intense. Isolated severe wind gusts will also be
possible. The storms are expected to move eastward into the lower
Missouri Valley during the evening and overnight period, and should
gradually increase in coverage as a low-level jet strengthens.
Although the storms are expected to become elevated, instability and
effective shear are forecast to be strong enough for a continued
isolated severe threat.
...Southern High Plains...
A subtle mid-level shortwave trough will move into the southern High
Plains on Thursday. Scattered thunderstorms are expected to develop
near this trough over parts of west Texas Thursday afternoon. Nearly
dry adiabatic lapse rates are evident on forecast soundings. This
environment should support isolated severe wind gusts, as a few of
the developing cells mix the stronger flow down to the surface
during the mid to late afternoon.
..Broyles.. 05/13/2026
$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/10)
-
From
Mike Powell@618:250/10 to
All on Thu May 14 07:59:47 2026
ACUS02 KWNS 140602
SWODY2
SPC AC 140600
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Thu May 14 2026
Valid 151200Z - 161200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS AND LOWER TO MID MISSOURI VALLEY...
...SUMMARY...
Severe storms with large to very large hail and severe wind gusts
will be possible Friday afternoon and evening in parts of the
central Plains and lower to mid Missouri Valley.
...Central Plains/Lower to Mid Missouri Valley...
West to west-southwesterly mid-level flow will remain in place on
Friday across the central U.S, as a subtle shortwave trough moves
into the central Plains. Ahead of this feature, moisture advection
will raise surface dewpoints into the mid to upper 60s F from the
eastern part of the central Plains into the lower to mid Missouri
Valley. A surface low will deepen over far western Oklahoma, with an
inverted trough extending northward into central Kansas and
northeastward into southeast Nebraska. Isolated convective
initiation is expected near and to the east of the surface trough
during the late afternoon. Convective coverage should gradually
increase in the evening as low-level warm advection strengthens.
By late afternoon, model forecast show a pocket of moderate to
strong instability over northeast Kansas. Forecast soundings at 00Z
in this area have MLCAPE in the 3500 to 4000 J/kg range, with 0-6 km
shear near 35 knots. 700-500 mb lapse rates are forecast to be in
the 8 to 8.5 C/km range. This environment will be favorable for
supercells with large hail, and hailstones greater than 2 inches in
diameter will be possible within the more intense cores. Supercells
will also be capable of severe wind gusts. During the late evening
and overnight, a severe threat may continue over parts of the
central Plains, as the low-level jet strengthens. Isolated severe
storms will be possible in northwestern Kansas late in the period,
as a secondary shortwave approaches.
Further south into parts of western Oklahoma, a capping inversion is
forecast to be in place during the late afternoon and early evening.
However, lapse rates are forecast to be very steep with some models
showing 700-500 mb lapse rates near 9 C/km. In addition, moderate
deep-layer shear is forecast. If a cell can initiate in spite of the
cap, then supercells with large hail would be possible.
...Mid to Upper Mississippi Valley...
Low-level moisture will gradually increase across the mid to upper
Mississippi Valley Friday afternoon and evening. Although
instability is forecast to remain weak, isolated thunderstorms may
initiate as a low-level jet moves into the region from the
southwest. By mid to late evening, MUCAPE is forecast to increase
into the 1000 to 1500 J/kg with effective shear near 40 knots over
much of the mid to upper Mississippi Valley. For this reason,
isolated severe storms will be possible, with strong wind gusts and
hail as the primary threats.
..Broyles.. 05/14/2026
$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/10)
-
From
Mike Powell@618:250/10 to
All on Fri May 15 09:24:43 2026
ACUS02 KWNS 150558
SWODY2
SPC AC 150556
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1256 AM CDT Fri May 15 2026
Valid 161200Z - 171200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE CENTRAL PLAINS...
...SUMMARY...
Severe storms capable of large to very large hail, wind damage and
perhaps a couple of tornadoes will be possible Saturday afternoon
and evening across parts of the central Plains. Scattered
thunderstorms will also pose potential for strong to severe winds
across the lower to mid- Missouri Valley.
...Synopsis...
A trough is expected to begin to deepen across the western US as
strengthening mid-level flow moves southward from the northern
Pacific Friday and Saturday. Downstream across the central US,
upper-level westerly flow will strengthen across the
central/northern Rockies with strengthening lee troughing across the
Plains. Persistent southerly flow through the southern and central
Plains should establish a broad warm sector across the Plains,
bounded to the west by a dryline and to the north by a diffuse warm
frontal zone. Scattered thunderstorm development is expected across
portions of the central high Plains near a developing surface low
and along the warm front, with additional thunderstorms possible
along the dryline from eastern Kansas to western Oklahoma. Scattered thunderstorms will also be likely across portions of the lower to
mid Missouri Valley.
...Central Plains...
As a short-wave trough moves across the central Plains late Saturday
afternoon, scattered thunderstorms are expected to develop near the
deepening surface low and the warm front by the afternoon across
eastern CO, northwest KS, and western NE. A broad warm sector will
be in place across much of the central Plains, with low to mid 60s
dew points reaching as far north as southern Nebraska. MLCAPE around
2000-2500 J/kg will be common by the afternoon. Initially, strong
deep layer shear and largely linear hodographs will support
potential for supercells capable of large to very large hail,
damaging winds, and a tornado. As the low-level jet strengthens into
the evening, low-level shear will increase but storm mode will also
likely shift to become more linear, with broken clusters/bowing
segments likely. A few of the mid-range hi-res CAMs depict a
stronger bowing segment moving across southern Nebraska into the
evening in concert with the increasing of the low-level jet. This
may present a more focused corridor of significant wind potential.
Confidence at this time in the exact location of this remains low.
Higher probabilities may be needed in subsequent outlooks if trends align.
...Western Oklahoma/northwest Texas...
Much of western Oklahoma and northwest Texas near the dryline will
remain capped at the base of the EML. Strong daytime heating and
favorable residence time within the dryline circulation may promote
an isolated supercell or two with potential for large to very large
hail and damaging winds by the late afternoon. Signal for
development is most favorable near the Red River in southern
Oklahoma where CAM guidance suggests potential and HREF calibrated
thunder probabilities are highest.
...Midwest/OH Valleys...
A leading mid-level shortwave trough with an enhanced belt of 50 kts
winds aloft will promote widely scattered thunderstorm development
into the mid- to upper Missouri Valley Saturday afternoon. MUCAPE
values on the order of 1000-2000 J/kg should support deep
convection, and effective bulk shear values near 30 knots within the
warm frontal zone may allow for organized convection with an
attendant threat for damaging wind.
..Thornton.. 05/15/2026
$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/10)
-
From
Mike Powell@618:250/6 to
All on Thu May 21 08:24:42 2026
ACUS02 KWNS 210552
SWODY2
SPC AC 210550
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Thu May 21 2026
Valid 221200Z - 231200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE
SOUTHERN PLAINS...
...SUMMARY...
Scattered strong to severe storms will be possible across portions
of the southern Plains with potential for large hail and damaging wind.
...Synopsis...
Two weak shortwaves, with one wave in central Plains and a secondary
wave into the Tennessee/Ohio Valleys, are forecast within the
broader Northern Rockies trough through afternoon on D2/Friday. A
surface low will be located across eastern New Mexico/southeastern
Colorado with a front lifting northward into Kansas and a dryline
extending southward into southwestern Texas. Another surface low
will develop across the Mississippi and Ohio Valleys with a warm
front lifting northward across Kentucky. These features will be the
focus for scattered thunderstorm development in both regions by the afternoon/evening.
...Southern and Central Plains...
Scattered thunderstorm development is expected across the Cap Rock
near the dryline in Texas and back into eastern New Mexico along the
high terrain Friday afternoon and evening. Steep low to mid-level
lapse rates will be in place across much of the region from eastern
New Mexico into western Texas. Dew points in the mid 50s to low 60s
and daytime heating will yield moderate instability amid deep layer
shear around 30-40 kts. This will promote initial supercells across
the high terrain with potential for additional multi-cell clusters
through time. These may grow upscale into an MCS into western
Oklahoma by the evening. The primary risk will be for large hail
before the damaging wind risk increases into the evening.
A few additional strong thunderstorms may extend into portions of
southern Kansas. The thermodynamic environment becomes less
favorable with northern extent due to widespread cloud cover and
morning precipitation. However, increasing mid-level flow and shear
may allow for a few organized cells with potential for large hail
and strong to severe wind further north.
...Tennessee and Ohio Valleys...
A warm front will lift across northern Tennessee into Kentucky
through the afternoon on Friday, with 60-70s dew points streaming
northward ahead of the approaching mid-level wave. Modest height
falls are expected across western Kentucky into the Ohio Valley,
with an increase in 850-700 mb flow. Widely scattered thunderstorms
are expected overnight into Friday morning. An increase in this
activity can be expected as a vorticity maxima and increasing large
scale ascent into the afternoon occurs. Though instability will be
marginal, guidance does suggest a plume of higher theta-e air may
advect into western/central Kentucky by the afternoon. In addition,
guidance suggests a few transient supercells will be possible with
potential for damaging winds and perhaps a tornado.
..Thornton.. 05/21/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)