RSS Mesoscale Discussions from Storm Prediction Center
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1256 AM CDT Tue Jul 14 2026
Valid 141200Z - 151200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...
...SUMMARY...
Severe thunderstorms with damaging wind gusts and large hail are
expected today across parts of northern New York and northern New
England. Additional storms with isolated severe gusts and hail will
be possible in parts of the northern Rockies and northern High
Plains.
...Northeast...
At mid-levels today, a fast-moving shortwave trough and an
associated jet streak will move southeastward across southeastern
Canada. At the surface, very moist air with surface dewpoints in the
70s F will be in place over much of the Northeast. As surface
temperatures warm, moderate instability will develop over much of
the region. By afternoon, an axis of low-level convergence is
forecast to develop along a pre-frontal trough, from near Lake
Ontario northeastward into far southern Quebec. This zone will be a
focus for convective initiation this afternoon. During the mid to
late afternoon, thunderstorms are expected to form near the surface
trough and move southeastward into northern New York and northern
New England.
As the mid-level jet approaches from the northwest, the entrance
region of jet will enhance lift and deep-layer shear across much of
the Northeast. By late this afternoon, RAP forecast soundings over
northern New England have 0-6 km shear near 50 knots, with MLCAPE
peaking in the 2500 to 3000 J/kg range. The environment will support
a mixed mode with supercells and organized line segments possible.
0-3 km lapse rates are forecast to peak near 7 C/km, which will
support a threat for severe wind gusts, especially with intense line
segments. A few severe gusts above 70 mph may occur. The potential
for large hail and tornadoes will be most likely with supercells.
The threat for supercells will be greatest from northern New York
into northern Vermont and northwest Maine, where mid-level lapse
rates are forecast to be near 7 C/km. Within this corridor, 0-3 km
storm-relative helicity is forecast to be in the 250 to 300 m2/s2
range, suggesting potential for a strong tornado.
...Northern Rockies/Northern High Plains...
At mid-levels today, flow will be southwesterly across the
northwestern U.S. At the surface, upslope flow will be in place from
the northern High Plains to the Rockies. Surface dewpoints will be
in the 60s F along an east-to-west moist axis, which is forecast
across eastern and central Montana. As surface temperatures warm, a
pocket of instability will develop near the moist axis. Thunderstorm
formation will be possible along this east-to-west zone and in the
higher terrain of western and central Montana. By late afternoon,
RAP forecast soundings in central Montana have MLCAPE around 2000
J/kg with 0-6 km shear near 35 knots. In addition, mid-level lapse
rates are forecast to be steep in the 7 to 8 C/km range. This will
support a threat for isolated severe wind gusts and hail.
..Broyles/Halbert.. 07/14/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1242 AM CDT Tue Jul 14 2026
Valid 151200Z - 161200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The potential for organized severe storms continues to appear low on
Wednesday.
... Synopsis ...
A broad mid-level ridge across the central United States will take
on an increasingly negative tilt on Wednesday, with the elongated
highest heights within the ridge found from the eastern Dakotas
southeast into southern Virginia and northern North Carolina. This
will occur in large part due to an eastern Pacific closed low
building the ridge axis northward into western Canada, a strong
shortwave trough impinging upon the northeast periphery of the
ridge, and a closed mid-level low undercutting southern portions of
the ridge as it begins to be drawn northwestward toward the main
belt of westerlies.
At the surface, generally hot conditions will be maintained across
most of the CONUS -- the exception largely being northern New
England. A moist airmass will remain entrenched across much of the
eastern US, with a southward advancing surface boundary across the
Northeast serving to delineate the warm, moist airmass to the south
from the cooler, drier airmass to the north.
... Northern New Jersey north/east into far southern New England ...
An unstable airmass will be in place along and south of the
aforementioned surface front where MUCAPE values should increase to
between 500-1500 J/kg during the afternoon. The front will be on the
southern fringe of the greater mid-level flow, contributing to
effective-layer shear on the order of 45 knots.
Modest height falls may overspread the frontal boundary during the
afternoon in association with an approaching mid-level speed
maximum. This may provide enough forcing for widely scattered
thunderstorm development in the region from the lower Great Lakes
into the northern Mid-Atlantic and far southern New England. The
best signal for initiation is along the coastal areas of southern
New England/New York, which will limit their potential to produce
severe weather before moving offshore. Should thunderstorm
initiation occur earlier in the day (and thus farther inland) or
thunderstorm coverage is greater than currently expected, a marginal
threat for large hail and damaging winds may be realized and severe
probabilities would need to be introduced in a later outlook.
... Western Montana ...
Thunderstorms will once again be possible on Wednesday, thanks in
large part to the continued presence of mid-level moisture and
modest diurnal heating. Model guidance suggests that widespread
cloud cover may limit afternoon heating, which would impact overall
instability and resulting thunderstorm intensity. Should robust
convection develop, the region remains beneath enhanced mid-level
flow that may be transported down to the surface as strong
thunderstorm winds/outflow. However, confidence in this occurring is
too low to warrant unconditional severe probabilities with this
outlook.
..Marsh.. 07/14/2026
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