No watches are valid as of Mon Jun 8 18:51:02 UTC 2026.MD 1029 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF SOUTHWESTERN INTO SOUTH CENTRAL NEBRASKA AND NORTHWESTERN INTO NORTH CENTRAL KANSAS
Mesoscale Discussion 1029
NWS Storm Prediction Center Norman OK
0149 PM CDT Mon Jun 08 2026
Areas affected...parts of southwestern into south central Nebraska
and northwestern into north central Kansas
Concerning...Severe potential...Watch possible
Valid 081849Z - 082145Z
Probability of Watch Issuance...60 percent
SUMMARY...Intensifying thunderstorm development, including a couple
of evolving supercells, appears increasingly probable by 3-5 PM CDT.
A severe weather watch is likely to be issued at some point, through
timing remains a bit uncertain.
DISCUSSION...In the wake of a subtle, weakening short wave
perturbation, stronger warm advection (based around the 700 mb
level) is focused along the western Nebraska/Kansas state border
vicinity. This is near the northern periphery of a plume of very
warm elevated mixed-layer air, and likely to persist into late
afternoon, based on latest Rapid Refresh output. Associated forcing
for ascent has been supporting thunderstorm development in an arcing
band across the North Platte toward Imperial NE vicinities, but
inflow of air emanating from a seasonably moist low-level
environment to its southeast has not been sufficient to maintain
particularly vigorous convection.
Closer to the state border vicinity, moistening associated with a
gradual veering of low-level flow from a general northeasterly to
east-southeasterly component, coupled with continued insolation,
appears likely to contribute to weakening inhibition for
boundary-layer parcels increasingly characterized by CAPE on the
order of 2000 J/kg. As this occurs, perhaps as early as 20-22Z,
potential for strong to severe thunderstorm development may begin to
more notably increase.
Due to veering of winds with height, deep-layer mean flow is
southerly and rather light, around 10-15 kts, so storms likely will
be initially slow moving. But deep-layer shear appears more than
sufficient for supercells, which should tend to propagate sharply to
the right (southeastward) through late afternoon. These may be
accompanied by potential for very large hail, perhaps some risk for
a tornado, and locally strong downbursts, before activity tends to
grow upscale.
..Kerr/Smith.. 06/08/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GID...LBF...GLD...
LAT...LON 40480001 40349910 39819833 39269894 39500024 40240075
40480001
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
MD 1028 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR LOWER OHIO RIVER VALLEY INTO THE MID-MISSISSIPPI VALLEY
Mesoscale Discussion 1028
NWS Storm Prediction Center Norman OK
0139 PM CDT Mon Jun 08 2026
Areas affected...lower Ohio River Valley into the mid-Mississippi
Valley
Concerning...Severe potential...Watch unlikely
Valid 081839Z - 082045Z
Probability of Watch Issuance...5 percent
SUMMARY...Scattered thunderstorms may bring a risk for isolated
strong wind gusts and perhaps a brief tornado through this
afternoon.
DISCUSSION...Latest visible satellite imagery depicts a well-defined
MCV located southwest of St. Louis, MO. Widely scattered to
scattered convection was ongoing downstream of this MCV from
east-central IL southward into the mid-Mississippi Valley along a
weak surface trough/wind shift, with a marginally more organized
convective band located in east-central Illinois recently producing
a measured 42 kt wind gust. Expectation is for this convection to
evolve east-northeastward through this afternoon. Despite weak
mid-level lapse rates, a very moist low-level air mass is
contributing to MLCAPE on the order of 1500-2500 J/kg. With latest
objective analysis depicting pockets of modestly steeper low-level
lapse rates of 7+ C/km and PWATs around 2 inches, isolated strong
wind gusts of 40-50 mph (and perhaps a localized damaging wind gust)
may occur with water-loaded downbursts. While weak effective shear
(generally less than 20-25 kts) will limit overall convective
organization, a brief tornado or landspout also cannot be ruled out
should a more robust low-level updraft interact with enhanced
surface vertical vorticity or weakly-curved, low-level hodographs in
the vicinity of the aforementioned weak surface trough/wind shift.
Watch issuance is not anticipated owing to the expectation for
limited severe coverage/magnitude.
..Chalmers/Smith.. 06/08/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LMK...OHX...IND...PAH...ILX...MEG...LSX...
LAT...LON 35818893 35898924 36138936 36698934 37228927 38778893
39218876 39868852 40178830 40328809 40408781 40378754
39898707 39168677 38408671 37908676 37578686 37088702
36558745 36058834 35888874 35818893
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MD 1027 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF EASTERN IOWA INTO SOUTHWESTERN WISCONSIN AND NORTHERN ILLINOIS
Mesoscale Discussion 1027
NWS Storm Prediction Center Norman OK
1258 PM CDT Mon Jun 08 2026
Areas affected...portions of eastern Iowa into southwestern
Wisconsin and northern Illinois
Concerning...Severe potential...Watch unlikely
Valid 081758Z - 081930Z
Probability of Watch Issuance...5 percent
SUMMARY...Scattered thunderstorms will evolve northeastward through
the afternoon today. A brief/weak tornado or landspout cannot be
ruled out.
DISCUSSION...Latest observations depict a well-defined MCV over
east-central Iowa, with a weak surface reflection located near Iowa
City, Iowa. A broken band of thunderstorms extends southeastward
from this feature into east-central and southern Illinois, perhaps
along a weak surface trough/wind shift. Regional VWPs (e.g.,
ILX/DVN) depict weakly-curved, low-level hodographs with ~50-75
m2/s2 0-1 km SRH within a very moist (dewpoints in the low/mid 70s
F) and weakly unstable (MLCAPE 500 to locally 1500 J/kg)
environment. Weak mid-level flow (less than 20-30 kts sampled by
these VAD profiles) and effective shear less than 20 kts (per latest
objective analysis) will limit overall storm organization and should
largely preclude marginal supercell structures. Enhanced surface
vertical vorticity, particularly in the vicinity of the weak surface
low in eastern Iowa and, to a lesser extent, along the surface wind
shift in Illinois, and modest low-level buoyancy (0-3 km CAPE up to
125 J/kg) may support some potential for a brief/weak landspout
tornado, however. A localized strong wind gust (40-45 mph) also
cannot be ruled out given the very moist environment. Watch issuance
is not expected owing to the limited nature of this severe threat.
..Chalmers/Smith.. 06/08/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LOT...ILX...MKX...DVN...ARX...
LAT...LON 42289188 42649195 43139171 43479123 43449066 43198997
42738931 41538823 40998810 40658804 40438821 40298857
40318883 40598927 40828966 41049005 41089035 41039068
41069098 41199129 41489159 41949179 42289188
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1152 AM CDT Mon Jun 08 2026
Valid 081630Z - 091200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
EASTERN COLORADO AND FROM NORTHERN INTO EASTERN KANSAS...
...SUMMARY...
Severe thunderstorms potentially capable of large to giant hail and
a couple of tornadoes are possible over the plains of eastern
Colorado. Scattered to numerous severe thunderstorms are possible
farther east over northern Kansas late this afternoon through the
late evening. Severe gusts ranging from 60-100 mph are possible
along with a risk for a couple of tornadoes.
...Eastern CO into Western NE/KS...
A belt of moderate southwesterly mid-level flow will be maintained
over the central High Plains to the downstream of a western U.S.
upper trough. A surface low near Dodge City, KS and moist easterly
low-level flow to its north, will contribute to upslope flow into
eastern CO and the CO Front Range. Strong heating and 50s to lower
60s deg F dewpoints and steep 700-500 mb lapse rates will result in
moderate to large buoyancy by mid afternoon. Elongated hodographs
will favor supercells with the more intense updrafts. Some increase
in low-level hodographs towards early evening coupled with a moist
boundary layer may aid in the risk for supercell tornadoes, in
addition to the risk for hail. Some of the latest model forecast
soundings suggest giant hail (3.0-4.5 inches in diameter) with the
more intense supercells over eastern CO late this afternoon into the
early evening. Severe gusts will also be possible with the stronger
storms with this activity diminishing by late evening.
...KS vicinity...
A very moist surface was analyzed this morning across the central
Great Plains to the south of a front across central and northern KS
to the east of a triple point. Model guidance shows lowest 100-mb
mean mixing ratios of 16-18 g/kg later this afternoon. This very
rich moisture coupled with heating to the south of the front and
early day outflow from storm activity over southwest NE, will result
in a very unstable airmass by late afternoon. Model guidance has
trended towards a severe MCS developing across northern KS and
moving east-southeastward into the lower MO Valley by late evening.
Although it remains unclear exactly how this will evolve, confidence
has increased with regard to a storm cluster and upscale growth
occurring on the northern rim of very rich moisture and a modest
southerly LLJ. Some indication exists for a couple of supercells to
develop ahead of the evolving cluster and eventual squall line.
Large hail and perhaps a tornado risk could accompany this activity.
Have increased severe-wind probabilities and intensity levels, with
the most intense phase of the squall line likely where the overlap
of greater effective shear (30-35 kt) and the large buoyancy
resides. A bow potentially capable of a swath of 60-80 mph gusts
(locally peaking 80-100 mph) is forecast, along with the possibility
for a couple of mesovortices capable of these locally higher gusts
and/or tornadoes. A gradual weakening is expected as this MCS moves
into western parts of MO late.
...Southern KS/Northwest OK...
A dryline will become established this afternoon from the eastern TX
Panhandle into south-central KS. Hot conditions along/west of the
dryline will help to initiate isolated thunderstorms. These
high-based supercells could pose an occasional threat of hail and
damaging winds for a few hours.
...Southern IL/Western KY...
An upper trough continues to lift northeastward across the mid MS
valley today, with a moist/moderately unstable air mass present from
southern IL southward. Mid-level lapse rates are marginal for
severe storms, and winds aloft are modest. Nevertheless, veering
winds-with-height and sufficient CAPE will pose an occasional risk
of strong storms capable of gusty winds or a tornado today.
..Smith/Chalmers.. 06/08/2026
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