RSS Mesoscale Discussions from Storm Prediction Center
WW 326 SEVERE TSTM IA MO 131405Z - 132000Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 326
NWS Storm Prediction Center Norman OK
905 AM CDT Sat Jun 13 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
South-Central Iowa
North-Central Missouri
* Effective this Saturday morning and afternoon from 905 AM until
300 PM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Bowing line segment currently moving through far
west-central Iowa is expected to continue
east-southeastward/southeastward over the next several hours. Strong
to severe gusts have already occurred with this line, with the
threat for damaging gusts expected to continue into south-central
Iowa and north-central Missouri. Isolated hail is also possible with
any storms that develop in the wake of this line segment.
The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 50 miles west northwest
of Lamoni IA to 30 miles north northeast of Kirksville MO. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU6).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 325...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
28035.
...Mosier
Read more
WW 0326 Status Updates
STATUS REPORT ON WW 326
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ENE STJ
TO 15 N OXV.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1119
..THORNTON..06/13/26
ATTN...WFO...DMX...EAX...
STATUS REPORT FOR WS 326
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC007-051-117-123-125-135-179-185-131740-
IA
. IOWA COUNTIES INCLUDED ARE
APPANOOSE DAVIS LUCAS
MAHASKA MARION MONROE
WAPELLO WAYNE
MOC001-061-079-081-115-117-121-129-171-197-211-131740-
MO
. MISSOURI COUNTIES INCLUDED ARE
ADAIR DAVIESS GRUNDY
HARRISON LINN LIVINGSTON
MACON MERCER PUTNAM
SCHUYLER SULLIVAN
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
Read more
WW 0325 Status Updates
STATUS REPORT ON WW 325
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 W BIE TO
15 S OLU TO 5 SE DNS.
..THORNTON..06/13/26
ATTN...WFO...OAX...GID...LBF...
STATUS REPORT FOR WS 325
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC071-085-129-137-145-155-165-131540-
IA
. IOWA COUNTIES INCLUDED ARE
FREMONT HARRISON MILLS
MONTGOMERY PAGE POTTAWATTAMIE
SHELBY
NEC023-025-055-109-131-151-153-155-159-177-131540-
NE
. NEBRASKA COUNTIES INCLUDED ARE
BUTLER CASS DOUGLAS
LANCASTER OTOE SALINE
SARPY SAUNDERS SEWARD
WASHINGTON
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
Read more
MD 1121 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF THE MID-MISSISSIPPI AND LOWER OHIO VALLEYS
Mesoscale Discussion 1121
NWS Storm Prediction Center Norman OK
1240 PM CDT Sat Jun 13 2026
Areas affected...portions of the mid-Mississippi and lower Ohio
Valleys
Concerning...Severe potential...Watch possible
Valid 131740Z - 131915Z
Probability of Watch Issuance...40 percent
SUMMARY...An ongoing convective cluster in southern Missouri has
exhibited some intensification over the past hour, with isolated
damaging wind gusts and large hail possible.
DISCUSSION...Latest GOES imagery and lightning data indicate that an
ongoing convective cluster in southern Missouri downstream of an MCV
over southeast Kansas has intensified some, with an uptick in
lightning and modest cloud top cooling noted over the past hour.
While denser cloud cover is present downstream of this cluster
across much of southeastern Missouri, clear conditions farther south
in northeast Arkansas and low-level warm, moist air advection are
contributing to a destabilizing air mass with minimal remaining
inhibition indicated by latest objective analysis and RAP forecast
soundings.
Latest high-res guidance continues to poorly capture this complex.
Thus, the exact evolution remains uncertain. However, guidance does
suggest that sufficient effective shear (25-30+ kts) will remain in
place owing, in part, to the presence of the upstream MCV (and
perhaps a second, weaker MCV over southern Missouri). Coupled with
the moderately unstable environment, it is possible that this
complex continues east-southeastward over the next couple of hours.
In this scenario, a greater threat for damaging wind gusts (and
perhaps an instance or two of large hail) may develop through the
afternoon should this cluster intensify. Trends are being monitored,
and a Severe Thunderstorm Watch may be needed pending further
intensification/persistence of this cluster.
..Chalmers/Mosier.. 06/13/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...MEG...LSX...LZK...SGF...
LAT...LON 37339130 37509096 37599042 37638986 37628952 37548922
37378899 37058872 36788864 36438866 36108891 35848933
35768969 35769008 35799057 35889100 36039147 36179174
36469199 36649199 36879188 36979178 37179155 37339130
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
MD 1120 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTHERN LOWER MICHIGAN
Mesoscale Discussion 1120
NWS Storm Prediction Center Norman OK
1200 PM CDT Sat Jun 13 2026
Areas affected...portions of northern Lower Michigan
Concerning...Severe potential...Watch unlikely
Valid 131700Z - 131830Z
Probability of Watch Issuance...20 percent
SUMMARY...An isolated threat for large hail, damaging wind gusts,
and perhaps a brief tornado may develop over the next 1-2 hours
across portions of northern Lower Michigan.
DISCUSSION...A broken band of thunderstorms has developed along a
weak confluence zone immediately downstream of a subtle, mid-level
shortwave trough evident over northern Lake Michigan in latest GOES
water vapor imagery. Northward moist advection ahead/south of this
band has resulted in surface dewpoints increasing to near 60 F, with
temperatures warming into the mid-70s. Modifying the 12z APX
observed sounding for these conditions suggests that weak buoyancy
has developed as of early afternoon, with around 500 J/kg MLCAPE
(locally up to 1000 J/kg per latest objective analysis). While
further destabilization is not expected to be substantial, strong
mid-level flow (50-60 kts sampled by the APX VWP at 2-3 km AGL) and
effective shear of 50-60 kts will support updraft organization as
ongoing convection evolves east-southeastward across northern Lower
Michigan over the next 1-2 hours.
Despite generally weak instability, the strong effective shear,
modestly steep mid-level lapse rates (around 7 C/km per latest
mesoanalysis), and steepening low-level lapse rates will promote
some potential for isolated large hail and damaging wind gusts with
any convection that can become better organized. A brief tornado
also cannot be ruled out given 0-1 km SRH of 100-150 m2/s2 sampled
by the APX VWP and indicated by latest objective analysis. Watch
issuance appears unlikely at this time owing to the expectation for
the severe risk to remain isolated and limited in magnitude.
..Chalmers/Mosier.. 06/13/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...APX...
LAT...LON 44978298 44748301 44518307 44338316 44228338 44188375
44198416 44258455 44338480 44478497 44788511 45028505
45198491 45278464 45408414 45428373 45368344 45208317
44978298
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 1119 CONCERNING SEVERE THUNDERSTORM WATCH 326... FOR FAR SOUTHERN IOWA INTO NORTH-CENTRAL MISSOURI
Mesoscale Discussion 1119
NWS Storm Prediction Center Norman OK
1151 AM CDT Sat Jun 13 2026
Areas affected...far southern Iowa into north-central Missouri
Concerning...Severe Thunderstorm Watch 326...
Valid 131651Z - 131815Z
The severe weather threat for Severe Thunderstorm Watch 326
continues.
SUMMARY...Damaging wind and isolated hail potential continues in
WW326.
DISCUSSION...A line of thunderstorms continues eastward across far
southern Iowa into north-central Missouri, producing more recent
gusts in to around 55-60 mph. Guidance suggests this will continue
eastward for another couple of hours across northern Missouri.
Sufficient MLCAPE around 1000 J/kg and deep layer shear around 30
kts will support potential for strong to severe wind and perhaps
some isolated instances of hail. This will eventually weaken with
time ahead of new convection developing to the west and as outflow
from a complex of storms moves northward this afternoon. A
downstream watch is not likely to be needed.
..Thornton.. 06/13/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LSX...DVN...DMX...EAX...
LAT...LON 40469413 40829385 40899322 40639248 40199212 39579225
39469300 39809383 39899416 39939422 40469413
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0753 AM CDT Sat Jun 13 2026
Valid 131300Z - 141200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...
...SUMMARY...
Scattered severe thunderstorms are likely today and tonight across
parts of the central and southern Plains to Missouri Valley and
Middle Mississippi Valley. Swaths of damaging wind gusts, large
hail, and a few tornadoes are all possible.
...Central/Southern Plains to Middle Mississippi Valley...
An active severe-weather day is anticipated with multiple rounds of
severe storms expected regionally today into tonight. Near the nose
of a southwesterly low-level jet, an initial early day severe risk
will focus across southeast Nebraska, where elevated/increasingly
organized storms are ongoing just after dawn, into southern Iowa and
northern Missouri. Large hail will remain possible, but the
potential for damaging winds may increase relatively early today as
storms spread east-southeastward.
Meanwhile, a more complex scenario exists farther south,
attributable to persistent predawn storms across the Ozarks, as well
as a decayed convective cluster and one or more residual MCVs across
Oklahoma and far southeast Kansas. These MCVs, as they focus deeper
convection along modifying outflow/differential heating zones,
should inspire renewed deeper convective development this afternoon
across parts of the Ozarks toward the Mid-South/middle Mississippi
Valley. This includes the potential for some supercells and
organizing clusters, with damaging winds and some hail as the
primary hazards through evening.
Farther west and later in the day, strong diurnal heating/steepening
low-level lapse rates preceding the surface low will result in
scattered thunderstorm development near/ahead of the
southeast-moving cold front, with the most intense development
likely favoring where the front intercepts the west-southwest
periphery of early day storms and any residual cloud cover/modifying
outflow. This will likely include central/eastern Kansas and
possibly far southeast Nebraska into western/northern Missouri.
Steep mid-level lapse rates atop rich boundary-layer moisture will
yield a strongly unstable air mass, which combined with around 40 kt
of effective shear, will support initial intense semi-discrete
supercells as then organizing clusters. All hazards seem likely
including large hail, with damaging winds potentially evolving as
the most prominent risk this evening, potentially including some
significant (75+ mph) wind gusts. The potential for tornadoes will
also exist, particularly late afternoon into evening as the
low-level jet increases, with modifying outflow potentially another
factor across west/southwest Missouri and possibly far eastern
Kansas and vicinity.
...Carolinas/Coastal Southeast...
Ample heating within a moist environment south of a front will lead
to moderately strong diurnal destabilization, with convective
development aided by the front and coastal sea breeze. Some
pulse-type locally severe storms capable of downbursts/wind damage
may occur this afternoon through around sunset.
..Guyer/Broyles.. 06/13/2026
Read more
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Sat Jun 13 2026
Valid 131630Z - 141200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...
...SUMMARY...
Scattered severe thunderstorms are likely today and tonight from
parts of the central and southern Plains to the Lower Missouri and
Middle Mississippi Valleys. Swaths of damaging wind gusts, large
hail, and a few tornadoes are all possible.
...Central/Southern Plains to Middle Mississippi Valley...
Several different areas are already convectively active this
morning, including south-central IA/north-central MO where a bowing
segment is moving southeastward through the region, and farther
south from central/southern MO into far west-central IL, where
elevated thunderstorm are being maintained by modest warm-air
advection. Most immediate severe potential is downstream of the
bowing segment in south-central IA/north-central MO where damaging
wind gusts and isolated hail are possible over the next few hours.
Thereafter, expansive coverage of the ongoing storms in
central/southern MO introduces notable uncertainty regarding the
extent and strength of afternoon destabilization.
General expectation is for the ongoing showers and thunderstorms to
persist, aided by mesoscale ascent attendant to an MCV traversing
the region. Cloud cover will limit heating, but ample low-level
moisture will still support moderate buoyancy. Moderate deep-layer
shear is anticipated over this area as well, with perhaps some more
mesoscale enhancement attendant to the MCV. As a result, a few
stronger embedded multicells and isolated supercells are possible.
Isolated large hail and damaging gusts could occur with the
strongest storms embedded within this likely broad area of showers
and thunderstorms.
A more complex scenario is anticipated along the western edge of the
MO cluster, extending back further westward into north-central KS.
Current surface analysis shows an outflow boundary over extreme
southeast NE arcing back through north-central KS to a low over far
northwest KS. A more substantial surface low exists over southwest
KS. Surface analysis also places a cold front from northwest IA
southwestward to just north of the northwest KS low in far southwest
NE. These boundaries should all influence convective evolution
today, with the outflow/differential heating boundary along the
western edge of the MO cluster likely playing a part as well.
Strong diurnal heating/steepening low-level lapse rates preceding
the surface lows will result in scattered thunderstorm development
near/ahead of the southeast-moving cold front, with the most intense
development likely favoring where the front intercepts the western
periphery of the outflow boundary. This intersection will most
likely be over central into northeast KS. Strong buoyancy and
moderate deep-layer shear will support robust updrafts capable of
large to very large hail early in the convective cycle, before
transitioning to a more linear mode as the front continues
southeastward.
Another area of afternoon thunderstorm development is anticipated
from southern MO into west-central MO and far southeast KS, along
the western edge of the outflow/differential heating associated with
the ongoing MO cluster. Like the area farther northwest, large to
isolated very large hail is anticipated initially. Additionally,
this region could act as a corridor for upscale growth as the
development along the cold front begins to interact with the more
in-situ development along this boundary. Damaging winds will be the
most prominent risk within this corridor this evening, potentially
including some significant (75+ mph) wind gusts.
Despite numerous boundaries, the environmental conditions (i.e. high
LCLs and modest surface wind) and anticipated convective evolution
(i.e. outflow-dominant storms with quick evolution towards a linear
mode) only suggest a low-probability tornado threat from discrete
storms. A somewhat higher tornado risk could materialize within any
more robust convective line that develops, particularly during
evening as the low-level jet increases.
...Lower MI...
Scattered thunderstorms are expected along and ahead of a cold front
moving through the region today. Strong low to mid-level flow could
support a few more organized storms, beginning across northern Lower
MI now and then extending back southwestward with time this
afternoon/evening. Primary risks are isolated large hail and
damaging gusts, but a brief tornado is possible as well.
...Carolinas/Coastal Southeast...
Ample heating within a moist environment south of a weak front will
result in moderately strong diurnal destabilization, with convective
development aided by the front and coastal sea breeze. Some
pulse-type locally severe storms capable of downbursts/wind damage
may occur this afternoon through around sunset.
..Mosier/Chalmers.. 06/13/2026
Read more
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1237 PM CDT Sat Jun 13 2026
Valid 141200Z - 151200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
GEORGIA NORTHWARD INTO PORTIONS OF SOUTHERN NEW ENGLAND...
...SUMMARY...
Scattered severe thunderstorms capable of damaging wind gusts are
expected across the Mid-Atlantic vicinity Sunday afternoon and
evening. Additional strong to severe storms are expected across the
Upper Ohio Valley and Lower Great Lakes area.
... Synopsis ...
Broad troughing will exist across the eastern US on Sunday with
several smaller-scale troughs moving through a longer-wave trough.
At the start of the forecast period, one shortwave trough will be
moving across the Northeast and a secondary low-amplitude trough
will approach the eastern US later in the day. As this happens,
low-mid-level southwesterly flow will increase to around 40 knots,
providing effective-layer shear sufficient for thunderstorm
organization.
Surface dewpoints will increase into the low 60Fs perhaps as far
north as central/southern New York ahead of an eastward advancing
cold front. Diurnal heating of this moist airmass should result in
MLCAPE perhaps as high as 1500-2500 J/kg across the southern
Mid-Atlantic, to perhaps 1000 J/kg across portions of New York.
Multiple rounds of thunderstorms will be possible along and ahead of
the surface front during the afternoon and evening. Damaging wind
gusts will be the main concern with these storms, although an
isolated tornado will also be possible. Strong consideration was
given to increasing wind probabilities to 45% (Level 3/Enhanced)
across the central/northern Mid-Atlantic region, but opted to defer
any upgrade to later outlooks after collaboration with local
offices.
Additional bands/clusters of storms are likely to develop during the
afternoon across portions of the Upper Ohio Valley into PA/NY. While
instability will be lower across this area, deep-layer flow will be
stronger. Linear bands and clusters will pose a risk for isolated
severe/damaging wind gusts through the evening.
... Southeast NM to the ArkLaTex ...
A southward sagging surface front/composite outflow will extend west
to east across the region. A very moist and moderately unstable
airmass will be in place ahead of the front. Isolated convection
cold pose a risk for strong wind gusts. Across southeast
NM/southwest TX, a few storms could also produce hail. Weak
large-scale ascent and convection becoming undercut by the surface
boundary will limit overall severe potential.
..Marsh.. 06/13/2026
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1137 AM CDT Sat Jun 13 2026
Valid 131700Z - 141200Z
...Morning Update...
Slight adjustments were made to the Dry Thunderstorm risk area based
on updated guidance. Surface observations across the Colorado
Plateau depict widespread RH values of 5-20%, owing to poor
overnight humidity recoveries across the Four Corners and central
Rockies. Mid/high-level water vapor satellite imagery portray
sufficient moisture surging northeastward from the Sonora and Baja
regions. Morning cloud cover over the Four Corners may inhibit
thunderstorm coverage this afternoon, however any isolated storms
that do materialize will remain elevated with little precipitation
efficiency. The 00z FGZ upper air sounding sampled 0.72" PWAT, which
is right at the 90th percentile of climatology. At 12z, the PHX
sounding sampled 1.23" PWAT, above the 90th percentile climatology
(and breaking the previous daily max of 1.08"). These observations
are on track with satellite derived total PWAT, with the highest
values (1" or greater) along/south of the Central Highlands where
the dry-to-wet thunderstorm transition likely exists. Some lightning
ignitions are possible this afternoon across portions the Great
Basin and western New Mexico, and erratic winds gusting to 30-35 mph
may exacerbate any new/ongoing wildfires (such as the Bear Fire in
western NM).
..Elizalde-Garcia.. 06/13/2026
.PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Jun 13 2026/
...Synopsis...
Isolated dry thunderstorms are forecast from the Four Corners region
into parts of the Great Basin during the afternoon as deep boundary
layer mixing with meager moisture content results in deep inverted-V
profiles across the area. Precipitable water content of 0.5-0.75 in
and tall LCLs exceeding 3.5 km will significantly reduce
precipitation efficiency, and with ERCs in the 90th-98th percentile
ranges, lightning ignitions will be a concern. Precipitable water
content increases to 1.0-1.25 in with southward extent, suggesting
the dividing line between wet/dry thunderstorms will be somewhere in
the central portions of Arizona and New Mexico. While the exact
details of where the dry-to-wet thunderstorm transition will set up
remains unclear, some lightning ignitions may be supported on the
periphery of more precipitation efficient downdrafts as well.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
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