No watches are valid as of Mon May 11 19:50:02 UTC 2026.MD 0706 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR 2SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI
Mesoscale Discussion 0706
NWS Storm Prediction Center Norman OK
0238 PM CDT Mon May 11 2026
Areas affected...2Southeast Louisiana and southern Mississippi
Concerning...Severe potential...Watch unlikely
Valid 111938Z - 112115Z
Probability of Watch Issuance...5 percent
SUMMARY...A few strong storms with gusty outflow winds possible the
next few hours.
DISCUSSION...In advance of a remnant MCV and the primary shortwave
trough over east TX, ascent is increasing across southern LA this
afternoon. Thunderstorms have already developed in southwest LA,
and should continue to expand eastward along a slow-moving front
into southeast LA and southern MS through the afternoon. Surface
temperatures have only warmed slowly as a result of persistent
clouds, but boundary-layer dewpoints near 70 F are supporting MLCAPE
of 1000-1500 J/kg with minimal convective inhibition along the
boundary. Though deep-layer shear appears sufficient for organized
storms at first glance, regional VWPs show very weak flow in the
lowest 3-4 km AGL. Thus, the potential for severe/persistent storms
will remain marginal and limited to isolated downbursts with
precipitation loading and/or melting of small hail.
..Thompson/Mosier.. 05/11/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MOB...JAN...LIX...LCH...
LAT...LON 31038870 30858896 30678986 30599059 30499131 30559165
30749177 30909176 31119121 31239037 31328956 31398902
31308877 31038870
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1131 AM CDT Mon May 11 2026
Valid 111630Z - 121200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE COASTAL
CAROLINAS ITO THE EASTERN FLORIDA PENINSULA...AND ACROSS THE CENTRAL
GULF COAST...
...SUMMARY...
Isolated severe storms with locally damaging wind gusts and hail are
possible this afternoon from the coastal Carolinas into the Florida
Peninsula, and along the central Gulf Coast.
...Synopsis...
Upper pattern across the CONUS this morning consists of western
ridging and eastern troughing. A pair of shortwave troughs are
embedded within the parent trough, one moving through the middle OH
Valley and the other farther south across TX. A convectively
generated vorticity maximum moving across the western Gulf precedes
the TX shortwave. Farther west, a shortwave trough is moving through
the northern periphery of the upper ridging over northern MT and
adjacent southern Saskatchewan.
Recent surface analysis places a low over the eastern NC/SC border
vicinity, with a cold front extending southwestward through the
Southeast and southern AL through the far western Gulf into Deep
South TX. Another low exists farther northwest over southern
Saskatchewan, with a cold front extending south-southwestward from
this low across eastern into south-central MT.
...Eastern SC/Far Southern NC...
Regional radar imagery shows isolated thunderstorms currently
ongoing near the surface low over the eastern NC/SC border vicinity.
A modest increase in buoyancy is anticipated ahead of these storms
over the next few hours. This buoyancy coupled with strong shear
could result in a few bowing segments capable of damaging gusts.
Additional isolated thunderstorm development is anticipated late
this afternoon as the weak cold front moves eastward across SC.
Moderate buoyancy and shear will support the potential for a few
more robust/organized updrafts capable of isolated hail and/or
damaging gusts.
...Eastern FL...
Warm/moist conditions are expected today over the FL Peninsula, with
temperatures over the interior warming into the 90s. Deep westerly
flow will focus convergence along the east-coast sea-breeze, leading
to scattered afternoon thunderstorms. Sufficient deep-layer vertical
shear may result in isolated strong-severe storms producing
gusty/damaging winds and hail.
...Northern/eastern ND into eastern SD...
Despite limited low-level moisture, modest buoyancy may develop late
this afternoon/early this evening amid cooling mid-level
temperatures and increasing mid-level moisture. This buoyancy will
develop atop a deeply mixed boundary layer, supporting the potential
for strong gusts if any updrafts can deepen/mature. Given the weak
and elevated nature of the buoyancy, developing a mature updraft
capable of lightning will be difficult and the current expectation
is for most of this activity to be shallow and non-lightning
producing. That being said, gusty surface winds are possible with
any convection does develop atop the deeply mixed boundary layer.
...Coastal LA/MS/AL...
The convectively generated shortwave trough over the western Gulf
mentioned in the synopsis (and associated surface low) are expected
to progress eastward throughout the day, while the stronger
shortwave trough back across TX also progress east-southeastward.
Easterly/southeasterly low-level flow will be maintained north of
the Gulf low, increasing low-level convergence along the slow-moving
frontal zone. This convergence will be augmented by ascent attendant
to the TX shortwave, with numerous showers and thunderstorms likely.
Poor lapse rates will limit buoyancy, although moderate deep-layer
shear could support a few deeper, more organized updrafts. Primary
risk over this area is heavy rain (as noted in the WPC Day 1
Excessive Rainfall Outlook), but a few water-loaded downbursts
capable of wind damage are possible as well.
..Mosier/Chalmers.. 05/11/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 PM CDT Mon May 11 2026
Valid 112000Z - 121200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE LOWER MISSISSIPPI VALLEY...THE FLORIDA ATLANTIC COAST...AND
THE CAROLINA COAST...
...SUMMARY...
Isolated severe storms with locally damaging wind gusts and hail are
possible this afternoon along the Carolina and Florida Atlantic
coasts as well as portions of the lower Mississippi Valley.
...20z Update...
The previous outlook largely remains on track with only minor
adjustments made. Risk probabilities were removed across eastern GA
where latest satellite imagery shows limited vertical development
within a broad cumulus field, likely owing to poor ascent given very
weak low-level convergence along a diffuse frontal zone. Latest
HRRR/RRFS guidance depicts negligible convective signals across this
region through tonight, suggesting the potential for severe
thunderstorms is low. Severe wind probabilities were similarly
trimmed across portions of southern LA where cold outflow associated
with a residual MCV over the northern Gulf is spreading northward.
Ahead of this boundary, temperatures warming into the low 80s within
a moist air mass may still support convection sufficiently deep for
a localized downburst concern (see MCD #706). Elsewhere, the
previous forecast (below) remains on track.
..Moore.. 05/11/2026
.PREV DISCUSSION... /ISSUED 1131 AM CDT Mon May 11 2026/
...Synopsis...
Upper pattern across the CONUS this morning consists of western
ridging and eastern troughing. A pair of shortwave troughs are
embedded within the parent trough, one moving through the middle OH
Valley and the other farther south across TX. A convectively
generated vorticity maximum moving across the western Gulf precedes
the TX shortwave. Farther west, a shortwave trough is moving through
the northern periphery of the upper ridging over northern MT and
adjacent southern Saskatchewan.
Recent surface analysis places a low over the eastern NC/SC border
vicinity, with a cold front extending southwestward through the
Southeast and southern AL through the far western Gulf into Deep
South TX. Another low exists farther northwest over southern
Saskatchewan, with a cold front extending south-southwestward from
this low across eastern into south-central MT.
...Eastern SC/Far Southern NC...
Regional radar imagery shows isolated thunderstorms currently
ongoing near the surface low over the eastern NC/SC border vicinity.
A modest increase in buoyancy is anticipated ahead of these storms
over the next few hours. This buoyancy coupled with strong shear
could result in a few bowing segments capable of damaging gusts.
Additional isolated thunderstorm development is anticipated late
this afternoon as the weak cold front moves eastward across SC.
Moderate buoyancy and shear will support the potential for a few
more robust/organized updrafts capable of isolated hail and/or
damaging gusts.
...Eastern FL...
Warm/moist conditions are expected today over the FL Peninsula, with
temperatures over the interior warming into the 90s. Deep westerly
flow will focus convergence along the east-coast sea-breeze, leading
to scattered afternoon thunderstorms. Sufficient deep-layer vertical
shear may result in isolated strong-severe storms producing
gusty/damaging winds and hail.
...Northern/eastern ND into eastern SD...
Despite limited low-level moisture, modest buoyancy may develop late
this afternoon/early this evening amid cooling mid-level
temperatures and increasing mid-level moisture. This buoyancy will
develop atop a deeply mixed boundary layer, supporting the potential
for strong gusts if any updrafts can deepen/mature. Given the weak
and elevated nature of the buoyancy, developing a mature updraft
capable of lightning will be difficult and the current expectation
is for most of this activity to be shallow and non-lightning
producing. That being said, gusty surface winds are possible with
any convection does develop atop the deeply mixed boundary layer.
...Coastal LA/MS/AL...
The convectively generated shortwave trough over the western Gulf
mentioned in the synopsis (and associated surface low) are expected
to progress eastward throughout the day, while the stronger
shortwave trough back across TX also progress east-southeastward.
Easterly/southeasterly low-level flow will be maintained north of
the Gulf low, increasing low-level convergence along the slow-moving
frontal zone. This convergence will be augmented by ascent attendant
to the TX shortwave, with numerous showers and thunderstorms likely.
Poor lapse rates will limit buoyancy, although moderate deep-layer
shear could support a few deeper, more organized updrafts. Primary
risk over this area is heavy rain (as noted in the WPC Day 1
Excessive Rainfall Outlook), but a few water-loaded downbursts
capable of wind damage are possible as well.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1229 PM CDT Mon May 11 2026
Valid 121200Z - 131200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST
KANSAS AND EXTREME NORTHERN OKLAHOMA NORTHEAST INTO SOUTHERN
WISCONSIN AND WESTERN INDIANA AS WELL AS ACROSS EASTERN FLORIDA
PENINSULA...
...SUMMARY...
Isolated severe storms with strong wind gusts and hail will be
possible on Tuesday from parts of southeast Kansas and far
northeastern Oklahoma northeastward into northern Illinois,
northwest Indiana and far southeast Wisconsin. Additional storms
capable of damaging winds will be possible across the eastern
Florida peninsula.
... Overview ...
The midlevel pattern will further amplify on Tuesday with a
negatively tilted tough moving onshore in the Pacific northwest.
This trough will aid the amplification of a downstream ridge over
the Rockies, and the amplification of this ridge will support the
subsequent downstream amplification of a trough over the eastern US.
Embedded within the eastern US trough, a closed midlevel low will
migrate southeast from Canada at the start of the period to being
over the Upper Great Lakes by the end. At the same time, a weak
midlevel vorticity maximum will weaken as it moves east across the
northern Gulf Coast and the Florida Peninsula as it is absorbed into
the larger scale longwave trough.
At the surface, a remnant cold front will continue slowly sagging
south across the Florida Peninsula as a weak low/associated MCS
moves across the state from west to east. Farther north and west,
another low will move east from the Northern Plains across central
Wisconsin into Lower Michigan. As this occurs, strengthening
lower-tropospheric northerly flow across the central US will push a
cold front south across the central US.
... Southeast Kansas/Northern Oklahoma into Southern Wisconsin and
Northwest Indiana ...
Southerly low-level flow will attempt to transport Gulf moisture
northward into the Central Plains northeast into the Upper Great
Lakes during the morning and early afternoon. This will occur along
the western periphery of an eastern US anticyclone and ahead of
south/southeast moving cold front. Atop this moisture return,
large-scale subsidence associated with the eastern portions of the
midlevel ridge across the Rockies will support warming lower
tropospheric temperatures. These warm low level temperatures will
provide a cap across the central US which should inhibit
thunderstorm development for much of the day and promote
uninterrupted northward moisture advection. The result will be
surface dewpoints rising into perhaps the low 50Fs as far north as
southern Wisconsin by early afternoon.
As diurnal heating warms this modified Gulf airmass, MUCAPE values
will struggle to increase to around 1250 J/kg across the southern
Central Plains to around 250 J/kg across Wisconsin owing to poor
lapse rates from the warm low-to-midlevel temperatures. That said,
at least isolated thunderstorms should develop across northern
Illinois/southern Wisconsin to the south of the surface low, where
surface convergence is greatest along the advancing front. As the
eastern US midlevel trough amplifies, the associated midlevel jet
will strengthen during the afternoon and evening across the Central
Plains. This kinematic profile will support at least a marginal wind
threat with any sustained thunderstorm.
To the south and west, slightly better low level moisture will
support greater instability, but warmer temperatures aloft and
weakening surface convergence will potentially limit thunderstorm
coverage. However, a marginal wind and hail threat will be possible
with any sustained thunderstorm.
... Eastern Florida Peninsula ...
Numerous thunderstorms are likely during the afternoon and evening
associated with the aforementioned sagging front and midlevel wave
moving across the region. High precipitable water values, long
hodographs within the cloud layer, and tall, skinny buoyancy
profiles will support the potential for a couple of wet damaging
downbursts with the strongest cores.
... Interior Oregon ...
During the late afternoon and overnight a vigorous, negatively
tilted midlevel trough will move into the area. Although low levels
will remain very dry, increasing midlevel moisture and midlevel
instability may be sufficient for a couple of thunderstorms. A very
dry sub-cloud layer and strong 700-500 millibar flow may support a
couple of isolated damaging wind gusts should thunderstorms develop.
Confidence in this scenario is too low to warrant unconditional wind
probabilities at this time.
..Marsh.. 05/11/2026
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