SPC AC 250057
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 PM CDT Tue Jun 24 2025
Valid 250100Z - 251200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL AND NORTHERN PLAINS...AND IN PARTS OF THE NORTHEAST...
...SUMMARY...
Large hail and severe wind gusts will be possible this evening in
parts of the central and northern High Plains. Isolated damaging
wind gusts will also be possible across parts of northern New York
into Vermont and New Hampshire early this evening.
...Central and Northern High Plains...
According to water vapor imagery, mid-level anticyclonic
southwesterly flow is currently present across much of the
north-central U.S. At the surface, a 1012 mb low is analyzed over
far eastern Colorado, with an upslope flow regime located over much
of the central and northern High Plains. Surface dewpoints within
the post-frontal airmass are mostly in the 60s F, which is
contributing to moderate instability over much of the region.
Scattered thunderstorms are ongoing along the western edge of the
moist airmass from eastern Colorado into southwest Nebraska.
Isolated storms are ongoing near the instability axis in central
Wyoming. As low-level flow increases early this evening, convective
coverage will likely be maintained as the storms move northeastward
into the lower elevations.
The most favorable environment for supercells appears to be in
central Wyoming. RAP forecast to the northwest of Casper, WY early
this evening have 0-6 km shear around 60 knots with 700-500 mb lapse
rates near 8.5 C/km. This may support a threat for isolated large
hail. Further to the southeast into parts of northeast Colorado and
southwest Nebraska, a cluster of strong to severe storms is ongoing.
Although a supercell will be possible within this cluster, the more
common storm type should be multicellular. This storm mode will
favorable severe gusts as the primary threat, especially with short
intense line segments.
Further to the east across parts of the central Plains, lower
Missouri Valley and southern Great Lakes, scattered thunderstorms
are ongoing near a front. Surface dewpoints in the upper 60s and
lower 70s F, combined with moderate instability and steep low-level
lapse rates, may be enough for marginally severe gusts early this
evening.
...Northern New York/Vermont, New Hampshire...
Mid-level westerly flow is currently located over much of the
Northeast. At the surface, a moist airmass is present across much of
the region with surface dewpoints mostly in the upper 60s to lower
70s F. An axis of moderate instability is analyzed from central New
York into western New England. To the north of the instability axis,
isolated to scattered storms are ongoing. In the vicinity of the
ongoing convection, the RAP has 20 to 25 knots of low-level flow,
0-3 km lapse rates near 7.5 C/km and moderate deep-layer shear. This
may be enough for severe wind gusts early this evening, associated
with the stronger multicells.
..Broyles.. 06/25/2025
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 241725
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1225 PM CDT Tue Jun 24 2025
Valid 251200Z - 261200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE CAROLINAS
TO THE SOUTHEAST...
...SUMMARY...
Severe wind gusts are possible over much of the Southeast, with
widely scattered strong to severe storms possible from the northern
High Plains eastward toward the Mid Atlantic.
...Synopsis...
The CONUS pattern will feature a trough across the western CONUS and
a strong ridge across the eastern CONUS Wednesday morning. This
pattern will deamplify during the period. A strong mid-level jet
streak will extend from northern Ontario to the Northeast with a
weak upper-low over Florida. A mid-level shortwave trough will move
from the central Plains to the western Great Lakes Wednesday
afternoon/evening.
...Central/northern High Plains...
A weak lee trough will extend from southeast Montana to northeast
Colorado. Weak to moderate instability will develop along this zone
during the afternoon and evening. Shear will be modest (25-30 knots)
with a few multicell clusters possible. Isolated large hail and
isolated severe wind gusts will be the primary hazards.
...Midwest into the western Great Lakes...
Moderate to strong instability is expected to develop south of a
warm front across the Midwest. A belt of 50+ knot mid-level flow is
forecast to overspread the warm sector and provide sufficient shear
for storm organization. In addition, some stronger low-level shear
will develop as a low-level jet strengthens during the
afternoon/evening. The stronger/more organized storms in the area
could have some tornado threat, particularly if any backed flow can
develop. At this time, the threat is expected too low for higher
severe weather probabilities.
...Ohio Valley into the Mid-Atlantic...
Additional storms are likely to develop within a moderate to
strongly unstable environment along a frontal zone from the Midwest
to the Mid-Atlantic. Shear will be mostly weak which should limit
the overall threat. However, strong instability and a very moist
environment may support some threat for wet microbursts.
...Carolinas into the Southeast...
Extreme instability is expected to develop from the Carolinas into
the Southeast amid mid to upper 70s dewpoints and temperatures in
the 90s. This extreme instability and scattered to widespread storm
development should be sufficient for a damaging wind threat. In
addition, stronger mid-level northeasterly flow is expected across
the eastern Carolinas into southern Georgia. This may result in even
greater storm organization and clustering where the stronger shear
is present. Some large hail is possible with damaging wind gusts as
the primary threat.
...Florida...
Cool temperatures aloft and moderate to potentially strong
instability is expected to develop across the Florida Panhandle on
Wednesday. Shear is forecast around 20 to 25 knots which may result
in a few multicell clusters capable of damaging wind gusts. The
greater threat should be mostly focused on the west coast where the
sea-breeze convergence is stronger and shear is slightly greater
amid westerly low-level flow.
..Bentley.. 06/24/2025
WUUS02 PTSDY2
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 241916
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 PM CDT Tue Jun 24 2025
Valid 261200Z - 271200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES...FROM THE
MID-ATLANTIC TO THE SOUTHEAST...AND NORTHEAST MONTANA VICINITY...
...SUMMARY...
Scattered strong storms are possible from the central Plains to
Lower Michigan, over parts of the Southeast, and over parts of
Montana on Thursday. Scattered damaging gusts appears to be the main
concern.
...Synopsis...
Somewhat zonal flow is expected across the northern CONUS on Friday
with a broad ridge across much of the southern CONUS. A moderate
mid-level jet streak will move across Montana with relatively weak
flow across the remainder of the CONUS. A weak upper low will drift
slowly northeast across the southeastern CONUS.
...Mid-Atlantic to the Southeast...
A broad area of moderate instability is forecast from the
Mid-Atlantic to the Southeast on Friday. Shear is expected to be
very weak through the period, but moderate instability and
relatively steep mid-level lapse rates beneath the upper low will
provide a thermodynamic environment favorable for some damaging wind
gusts. More focused areas of strong to severe storms may exist near
outflow boundaries from D2/Thursday convection.
...Central Plains to the western Great Lakes...
Moderate to strong instability is forecast to develop along a
frontal zone from Kansas to Wisconsin on Friday afternoon/evening.
Shear is expected to remain weak (20 to 25 knots), but strong
instability will support the threat for some damaging wind gusts.
...Northeast Montana Vicinity...
Moderate mid-level flow is expected to overspread northeast Montana
on Friday where a deeply mixed boundary layer (above 3km) is
forecast. While instability will not be that great due to limited
moisture, it should be sufficient for a few storms. Moderate shear
(25 to 30 knots) and a deeply mixed boundary layer will support a
threat for some severe wind gusts Friday afternoon/evening.
..Bentley.. 06/24/2025
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
|
