RSS Mesoscale Discussions from Storm Prediction Center
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0158 AM CDT Mon Mar 09 2026
Valid 091200Z - 101200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
MID-SOUTH REGION AND CENTRAL GULF STATES...
...SUMMARY...
Severe thunderstorms are expected across the Mid-South region and
central Gulf states.
...Mid-South/Central Gulf States...
Weak, low amplitude short-wave trough is currently located over the
southern High Plains. This feature is forecast to advance into
central OK later this morning before shifting into eastern AR by
10/00z, then into the southern Appalachians during the overnight
hours. Despite this short wave, large-scale height rises are
forecast through the period across much of the eastern CONUS. As a
result, LLJ will likely prove instrumental in convective initiation
as low-level warm advection should extend along a corridor from the
southern Plains into the northern Gulf states.
Early this morning, 60F surface dew points were observed into
portions of the Arklatex. Latest model guidance suggests mid 60s dew
points will advance to near I40 across AR and these values should
spread into northern MS/AL by late afternoon. Given the strength of
the LLJ currently observed across north-central TX/OK, there is
increasing confidence that elevated convection may develop just
before sunrise across southeast OK. This activity would then
potentially grow upscale as it approaches the MS River. Latest HREF
members generally agree with this scenario and multiple thunderstorm
clusters and possibly an MCS-like cluster could evolve with time.
Strong deep-layer shear favors the potential for supercells, and
hail should be the primary concern with this activity. Severe threat
will spread southeast as thunderstorms spread toward
northern/central AL by late afternoon, potentially into western GA
during the evening.
...Southern AZ...
Strong upper low is forecast to advance toward the northern Baja
Peninsula by 10/00z, eventually shifting into northwest Mexico, just
south of the AZ border by the end of the period. Steep lapse rates
are forecast across southern AZ within a favorable zone for
large-scale ascent. Profiles suggest scattered convection will
develop and spread north across this region. Some consideration was
given to adding 5 percent severe hail/wind probabilities to this
region, but forecast soundings suggest this activity should struggle
to attain severe levels. Even so, small hail and gusty winds could
accompany the strongest convection.
..Darrow/Lyons.. 03/09/2026
Read more
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Mon Mar 09 2026
Valid 101200Z - 111200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS
NORTHEAST MISSOURI...FAR SOUTHEAST IOWA...AND PARTS OF
NORTHERN/CENTRAL ILLINOIS INTO NORTHWEST INDIANA...
...SUMMARY...
Scattered severe thunderstorms are forecast on Tuesday from the
southern Plains into the southern Great Lakes vicinity. All severe
hazards are possible.
...Synopsis...
A complex scenario for severe thunderstorm potential is expected on
Tuesday and Tuesday night from the Southern Plains to the Mid-MS
Valley/southern Great Lakes vicinity. A somewhat bi-modal severe
risk appears possible within a split-flow upper level pattern. All
severe hazards appear possible, especially within a corridor across
portions of TX, and a second corridor from northern MO into
northern/central IL and northwest IN.
Expansive area of enhanced southwesterly flow will overspread the
southern Plains into the Upper Great Lakes, aided by two separate
upper troughs. The first is associated with an upper low/trough
across northwest Mexico and the Southwest, which will shift east
into the southern High Plains by Wednesday. The second is a broad
but deepening upper trough moving across the northern/central Plains
toward the Upper Midwest. Two areas of low pressure are expected to
develop with the approaching of these upper systems, one over the
central/southern High Plains and the other across the Lower
MO/Mid-MS valley. A dryline/Pacific front will be oriented across
western TX, while a warm front extends west to east from near
northern MO/southeast IA into northern IL/IN. By evening, a cold
front will begin to develop southeast across KS/MO/IA/IL/IN, and the
Pacific front will shift east across central TX. These boundaries
will be the focus for scattered to widespread thunderstorm
development from late afternoon into the overnight hours.
...Mid-MO Valley to southern Great Lakes vicinity...
Capping will likely suppress convection for much of the day within a
strong warm advection regime. Surface dewpoints are expected to
climb into the low/mid-60s south of the warm front beneath steep
midlevel lapse rates. This will foster 1000-2000 J/kg MLCAPE by peak
heating. Convection is expected to develop within the 21-00z time
frame when a 40 kt low-level jet is expected to overspread the
region. Supercell wind profiles are noted in forecast soundings,
with hodographs exhibiting enhanced low-level curvature, with
lengthened/straight hodographs above 2-3 km. Given a favorable
thermodynamic environment, large hail to 2.5 inches appears possible
with storms both within the warm sector and initial activity that
may develop within the cooler air north of the front. Furthermore,
any cells that develop within the warm sector and interact with the
front will encounter enhanced low-level shear/SRH and tornadoes
(some EF-2+) will be possible. With time during the evening,
convection will likely grow upscale into one or more
southeast-advancing linear segments near the advancing cold front.
Damaging winds will be possible with this activity overnight.
...Southern Plains vicinity...
Convection is expected to develop along the surface dryline across
western TX by mid to late afternoon. Initial supercells are possible
and could produce large hail (to around 2 inch diameter) and a
couple of tornadoes. Convection may quickly grow upscale as the
Pacific front overtakes the dryline and large-scale ascent increases
rapidly by 00z.
Uncertainty increases with northward extent across OK/KS into
southern MO/AR. These areas will be within the broad warm sector and
moderate to strongly sheared environment. However, this area will
also be between the two areas of stronger ascent. Some capping may
persist and it is unclear how convection may evolve across these
areas.
..Leitman.. 03/09/2026
Read more
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0220 AM CDT Mon Mar 09 2026
Valid 111200Z - 121200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE ARKLATEX
AND LOWER MISSISSIPPI VALLEY NORTHEAST THROUGH THE OHIO VALLEY...
...SUMMARY...
Isolated to scattered severe thunderstorms are possible on Wednesday
from the ArkLaTex and Lower Mississippi Valley northeastward through
the Ohio Valley vicinity.
...East Texas northeast to the Ohio Valley vicinity...
A split-flow regime will continue into Wednesday, with upper
troughing over the central U.S. remaining bifurcated through much of
the period. In the southern branch, a closed low/upper shortwave
trough will migrate from TX to the Lower MS Valley. Meanwhile, the
northern stream upper trough over the northern Plains/Upper Midwest
will develop east across the Upper Great Lakes/Midwest. Ahead of
these features, strong southwesterly deep-layer flow will extend
from east TX into the Mid-Atlantic/New England. At the surface, a
cold front will extend southwest from a surface low over southern
Lower MI into western OK. This front will advance southeast through
the period, becoming oriented from the Mid-Atlantic coast to the
central Gulf coast by Thursday morning.
Strong warm advection ahead of the front will transport Gulf
moisture as far north as the Mid-Atlantic and southern New England.
Ongoing convection is expected ahead of the front across portions of
the ArkLaTex into the Midwest. This, along with the warm advection
regime resulting in widespread cloudiness, lends to uncertainty in
how the downstream airmass will destabilize, especially with
northeast extent into parts of the Ohio Valley vicinity. Somewhat
stronger destabilization is likely across the Lower MS Valley where
richer Gulf moisture will reside. Strong vertical wind profiles will
support damaging wind potential with even modest instability. Linear
convection is the most likely storm mode given deep-layer flow
parallel to the surface boundary and strong large-scale ascent
overspreading the boundary. If discrete cells can form, some tornado
potential will exist closer to a deepening surface cyclone in the
vicinity of the upper Ohio Valley, and perhaps near a secondary
surface low over the lower MS Valley, though this scenario remains
highly uncertain.
..Leitman.. 03/09/2026
Read more
