SPC AC 080554
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1154 PM CST Wed Jan 07 2026
Valid 081200Z - 091200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
THE SOUTHERN PLAINS EAST AND NORTHEASTWARD INTO THE MID MISSISSIPPI
AND LOWER OHIO VALLEYS...
...SUMMARY...
Thunderstorms with a threat for isolated severe wind gusts and a
brief tornado will be possible today into tonight from parts of the
southern Plains eastward into the mid Mississippi and lower Ohio
Valleys.
...Southern Plains/Ozarks...
At the start of the period, a mid-level trough and an associated jet
streak will be located in the southern High Plains. An axis of weak
instability is forecast from northwest Texas northeastward across
Oklahoma. Thunderstorms will likely be ongoing at 12Z along parts of
this corridor, supported by a strong low-level jet. Forecast
soundings near the instability axis this morning have MLCAPE around
750 J/kg with 0-6 km shear in the 55 to 65 knot range. Low to
mid-level lapse rates should be modest remaining in the 6 to 6.5
C/km range. This should be enough for an isolated hail threat with
cells that rotate. In addition, a fast northeastward storm motion
could be enough to produce marginally severe winds at the surface. A
brief tornado will also be possible. The isolated severe threat
could persist into the afternoon as the line moves into the Ozarks.
...Mid Mississippi and Lower Ohio Valleys...
A mid-level trough, and an associated 55 to 65 knot low-level jet,
will move quickly northeastward into the mid Mississippi Valley this
afternoon. Ahead of the trough, strong moisture advection will take
place, with surface dewpoints increasing into the upper 50s and
lower 60s F over much of the mid Mississippi Valley. In response, an
axis of weak instability is forecast to develop by afternoon from
central Arkansas northeastward into south-central Illinois. A line
of strong thunderstorms is expected to develop along the instability
axis in the late afternoon and early evening. This line should move
east-northeastward across the mid Mississippi and lower Ohio
Valleys. RAP forecast soundings along and near the instability axis
at 00Z have MLCAPE around 500 J/kg, with 0-6 km shear in the 60 to
70 knot range. This, combined with large-scale ascent ahead of the
trough, will support a marginal severe threat. Any line segment that
can become organized could produce isolated severe wind gusts, and
possibly a brief tornado.
At this point, there is uncertainty as to where the greatest severe
threat will be as the system ejects northeastward across the mid
Mississippi Valley. It is possible that the potential for severe
wind gusts could become maximized near the exit region of the
mid-level jet streak early this evening from east-central Missouri
across central Illinois into western Indiana. For this reason, have
expanded the Marginal Risk area northeastward to account for this
possibility.
..Broyles/Squitieri.. 01/08/2026
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
SPC AC 080659
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CST Thu Jan 08 2026
Valid 091200Z - 101200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF LA/MS
AND ADJACENT PARTS OF SOUTHEAST AR AND WESTERN/NORTHERN AL...
...SUMMARY...
Severe thunderstorms are possible on Friday from Louisiana into
parts of the Mid-South and Southeast.
...East TX into the Lower MS Valley and Mid-South...
In the wake of a departing mid/upper shortwave trough and surface
low, a cold front is forecast to slow down by afternoon and perhaps
become nearly stationary from near the ArkLaTex region to the
Mid-South. As an upstream mid/upper trough approaches from the west,
cyclogenesis is expected along this front, with the surface low
expected to move east-northeastward toward the TN Valley by Saturday
morning.
Seasonably rich low-level moisture will be in place within the warm
sector of this cyclone, and low-level and deep-layer shear will
increase with time as the frontal wave develops. However, guidance
continues to vary somewhat regarding the extent of phasing between
the approaching shortwave trough across the southern Plains and a
strong shortwave trough digging southeastward from the Canadian
Prairies. There are also varying solutions regarding the coverage of
early-day convection, and the extent to which it hampers warm-sector
destabilization as low-level and deep-layer shear strengthens.
Early-day storms within the modest warm-advection regime from east
TX into the lower MS Valley could pose a low-probability threat of
all severe hazards. An increase in the severe potential could evolve
from late afternoon into the evening, as low-level and deep-layer
shear begin to strengthen in response to the approaching trough.
Organized clusters and a few supercells will be possible, with an
attendant damaging-wind and tornado threat that may continue into
late Friday night. However, if early-day convection becomes
widespread with increasingly prominent outflow (as indicated by some
00Z HREF members), the magnitude and north/east extent of the
organized severe threat may be relatively limited. The greatest
relative confidence in an organized severe threat is currently
across parts of LA into central/southern MS, with a more conditional
threat to the north and east of this area.
..Dean.. 01/08/2026
WUUS02 PTSDY2
SPC AC 080828
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CST Thu Jan 08 2026
Valid 101200Z - 111200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
SOUTHEAST INTO PARTS OF THE CAROLINAS AND SOUTHERN VIRGINIA...
...SUMMARY...
Isolated severe thunderstorms are possible on Saturday from the
Southeast into parts of the Carolinas and southern Virginia.
...Southeast into the Carolinas and Virginia...
An upper trough will amplify and move eastward across the eastern
CONUS on Saturday, as an embedded midlevel cyclone moves across the
Great Lakes region. A surface low initially over the TN Valley will
move towards the Mid Atlantic, as another surface low develops
farther north near the lower Great Lakes.
Widespread convection will likely be ongoing Saturday morning from
parts of the Southeast into the southern Appalachians vicinity.
Deep-layer flow/shear will be strong, and seasonably rich low-level
moisture will be in place ahead of an eastward-moving cold front.
Organized cells/clusters that develop during the D2/Friday period
may persist through at least the first part of the day, with a
continued threat for at least locally damaging wind, and potentially
a tornado threat where vigorous surface-based convection can
persist. Longevity of the threat with time and eastward extent
remains uncertain, with an expected tendency for weakening buoyancy
and diminishing ascent across the warm sector. Some potential for
locally damaging wind could spread into parts of the Carolinas and
Virginia before the threat diminishes as the cold front moves
through.
A Marginal Risk has been included for areas forecast to be
along/ahead of the cold front at the start of the period and
near/south of the consensus surface-low track. A Slight Risk was
considered for parts of eastern MS into AL and western GA, as a
continuation of the severe threat from late D2/Friday into Saturday
morning, but deferred to future outlooks given uncertainty regarding
the impact of widespread convection within the warm sector by the
beginning of the D3/Saturday period.
..Dean.. 01/08/2026
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 1930Z
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