RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Mon Jun 15 10:32:01 UTC 2026.
No Mesoscale Discussions are in effect as of Mon Jun 15 10:32:01 UTC 2026.
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Mon Jun 15 2026
Valid 171200Z - 181200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MID-MISSISSIPPI VALLEY INTO INDIANA...
...SUMMARY...
An all-hazards severe thunderstorm episode is expected across
portions of the Middle Mississippi Valley into Indiana on Wednesday.
Intense thunderstorms may produce swaths of damaging wind, as well
as strong tornadoes and large hail.
...Midwest...
A midlevel shortwave trough is forecast to move from the northern
Plains through the Upper Midwest and Great Lakes region on
Wednesday. As this occurs, very strong deep-layer flow, especially
for this time of year, will move across portions of the Mid-MS
Valley into the Ohio Valley. A westerly 500 mb jet streak
characterized by at least 70-80 kt will overspread parts of
IA/MO/IL/IN in the afternoon and evening. Meanwhile, a 50+ kt
southwesterly 850 mb low-level jet will spread across the same area
during the afternoon/evening, just ahead of an
east/southeast-advancing surface cold front. These strong wind
fields, in conjunction with a surface low moving eastward across MN
and the Upper Great Lakes, will aid in northward transport of rich
boundary layer moisture (upper 60s to near 70 F surface dewpoints).
Cooling aloft will steepen midlevel lapse rates, and moderate to
strong destabilization is expected across the warm sector. Overall,
this pattern should support numerous severe storms. While convective
evolution remains uncertain, it is likely that at least some initial
supercell risk will unfold during the afternoon and early evening
(particularly across MO/IL), with potential for one or more bowing
MCSs developing with time. This environment will support a risk for
all severe hazards, and particularly swaths of damaging winds, and
strong tornadoes.
Some uncertainty remains regarding the northward extent of the
severe risk. Most medium range guidance indicates a lead shortwave
impulse may move across IA/IL early in the day. Coupled with strong
warm advection across the region, morning thunderstorm develop
near/north of a warm front oriented from southeast MN into northeast
IL at midday could suppress northward development of the warm front.
Likewise, the southwest extent of the risk area into portions of
KS/OK may be limited by capping concerns, and weaker forcing for
ascent. Meanwhile, the southward extent of the severe risk across
the Ohio Valley will be modulated by the stronger westerly component
of mid/upper flow overnight and slow southward movement of the
surface cold front. The risk area may shift some in coming days as
surface boundaries and other mesoscale details become better
resolved.
..Leitman.. 06/15/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0257 AM CDT Mon Jun 15 2026
Valid 181200Z - 231200Z
...DISCUSSION...
...Day 4/Thursday -- Mid-Atlantic/Northeast...
Strong mid/upper level westerly flow will overspread portions of the
Ohio Valley into the Northeast as a shortwave trough pivots across
Quebec/Ontario and the Northeast U.S. on Thursday. Quite a bit of
uncertainty exists regarding severe potential. Early day convection
and cloud cover may limited destabilization from the Upper Ohio
Valley into parts of the southern Mid-Atlantic and northeast.
Additionally, stronger mid/upper level flow will become increasingly
displaced to the north from richer boundary-layer moisture and
stronger instability. Nevertheless, sufficient overlap of strong
flow atop a moist airmass should occur from southern Ohio/eastern KY
into the Mid-Atlantic, supporting a risk for severe thunderstorms on
Thursday. This area will likely shift some in the coming days as
mesoscale details become better resolved.
...Days 5-8/Friday-Monday...
A surface front will sag southward across the Gulf Coast states,
with surface high pressure centered over the Mid-South vicinity on
Friday. This should suppress the overall severe risk as richer
boundary layer moisture remains confined to TX and the Gulf Coast.
On Saturday, northward transport of Gulf moisture across the Plains
is expected beneath a building upper ridge. By Sunday, an upper
trough over the West may eject eastward into the Plains, resulting
in some return of severe thunderstorm potential this weekend, though
spread among forecast guidance is quite large and predictability is
low late in the forecast period.
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0144 AM CDT Mon Jun 15 2026
Valid 151200Z - 161200Z
...Synopsis...
Between a large-scale trough encompassing the eastern two-thirds of
the CONUS and an upper ridge over the West, a robust midlevel speed
max will overspread the northern/central Plains during the day. At
the same time, a related cold front will advance southeastward
across the region.
Along/behind the cold front/surface trough, ample diurnal heating
will result in a well-mixed boundary layer, with 15-20 percent RH
expected across parts of eastern WY into the NE Panhandle and
vicinity. Here, enhanced low/midlevel flow along the periphery of
the passing speed max and a tightening pressure gradient will result
in 15-25 mph sustained northwesterly surface winds. These dry/breezy
conditions atop dry/receptive fuels will yield elevated to locally
critical fire-weather conditions during the afternoon.
Despite relatively weaker upper-level support, strong terrain-driven
winds of 15-20 mph (locally greater in gap-flow areas and higher
elevations) and 10-15 percent RH will promote locally elevated fire
weather conditions across parts of the eastern Great Basin, Four
Corners, and Central Rockies. However, these conditions appear too
localized for highlights at this time.
..Weinman.. 06/15/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0144 AM CDT Mon Jun 15 2026
Valid 161200Z - 171200Z
...Synopsis...
Along the northeastern periphery of an upper ridge over the West, a
midlevel trough and accompanying 70-80-kt speed max will advance
southeastward across the Northwest and northern Rockies on Tuesday.
In response, a surface low will deepen while advancing
east-southeastward across the northern Plains.
...Northern Intermountain West...
On the southern edge of the robust midlevel speed max, strong
deep-layer west-northwesterly flow will overspread a warm/dry air
mass during the afternoon. This, combined with a tightening pressure
gradient, will result in 15-25 mph sustained westerly surface winds
amid 15-20 percent afternoon RH. Given increasingly dry/receptive
fuels across the region, elevated to locally critical fire-weather
conditions are expected. In particular, locally critical conditions
are most likely in the gap-flow areas through the Cascades and the
Snake River Plain. However, these conditions appear too localized
for Critical highlights at this time.
...Eastern Great Basin into the Rockies and adjacent Plains...
Despite relatively weaker midlevel flow compared to areas north and
northwest, at least moderate midlevel flow will promote an expansive
area of breezy/gusty west-northwesterly surface winds across the
region. These breezy/gusty winds coupled with single-digit to
lower-teens RH will yield broad elevated fire-weather conditions
during the afternoon. Stronger deep-layer flow in closer proximity
to the midlevel speed max will favor stronger sustained surface
winds (around 20-25 mph) over parts of southern WY, where locally
critical conditions are possible. Locally critical conditions will
also be possible in terrain-favored areas throughout the Elevated
area.
..Weinman.. 06/15/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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