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DAY2SVR: Nws Storm Predi
From
Mike Powell@618:250/6 to
All on Wed Apr 29 13:58:00 2026
ACUS02 KWNS 290454
SWODY2
SPC AC 290452
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1152 PM CDT Tue Apr 28 2026
Valid 301200Z - 011200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE THURSDAY
AFTERNOON AND EVENING ACROSS PARTS OF THE RIO GRANDE NEAR THE TEXAS
BIG BEND...
...SUMMARY...
A couple of strong storms may impact the Rio Grande River vicinity
near the Texas Big Bend late Thursday afternoon and evening, perhaps accompanied by at least some risk for severe hail.
...Discussion...
It still appears that an elongated area of lower mid-level heights
will continue a slow east-southeastward progression across much of
the upper Mississippi Valley through northern Atlantic Seaboard,
with an embedded cyclonic circulation redeveloping southeastward
through the Great Lakes region. In its wake, split westerlies
likely will remain confluent across and east of the Rockies, as a
short wave perturbation emerges from the subtropical eastern Pacific.
There appears a much better consensus within latest model output
concerning the inland progression of this perturbation, which is now
generally forecast to accelerate across northern Mexico and adjacent
portions of the U.S. Southwest, toward the Texas Big Bend vicinity
Thursday through Thursday night. Downstream short wave ridging is
forecast to gradually shift east of the southern Rockies, across the
southern Great Plains through Gulf Coast, while subtropical ridging
centered across southern Mexico undergoes further suppression.
In lower levels, to the east of the Rockies, cool surface ridging
will be maintained across much of the Great Plains and
Mississippi Valley into Southeast. Most guidance now indicates that
the frontal zone on the leading edge of this air mass will make
slow, but steady, southward progress into and across the Texas Big
Bend and Hill Country, immediate upper Texas/Louisiana coastal
vicinity, and northern Florida.
Forcing for ascent associated with lower/mid-tropospheric warm
advection, downstream of the approaching subtropical perturbation,
may contribute to multiple rounds of thunderstorm development
above the stable surface-based air across parts of the Permian Basin
and Texas South Plains through much of central Texas by late
Thursday night. Based on latest model output, including Rapid
Refresh and NAM forecast soundings, thermodynamic profiles seem
unlikely to support severe hail. One exception might develop within
moist upslope flow into a more strongly heated environment across
the higher terrain near and south of the Texas Big Bend. Beneath
moderate to strong mid-level flow, the initiation of a couple of
supercells appears possible. However, this activity is expected to
weaken as it acquires less unstable updraft inflow to the east of
the higher terrain.
Otherwise, the front might provide a general focus for widely
scattered thunderstorm activity near the Gulf coast vicinity, while destabilization beneath cool mid-level air across the Great Basin
into southern Rockies supports scattered, mostly diurnal
thunderstorm activity.
..Kerr.. 04/29/2026
$$
--- ScorpioBBS/QWK v0.32a (Linux/x86_64)
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/6 to
All on Thu Apr 30 15:06:00 2026
ACUS02 KWNS 300456
SWODY2
SPC AC 300454
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1154 PM CDT Wed Apr 29 2026
Valid 011200Z - 021200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY AFTERNOON
INTO FRIDAY NIGHT ACROSS PARTS OF MIDDLE TEXAS COASTAL
AREAS...SOUTHEASTERN LOUISIANA...THE FLORIDA...
...SUMMARY...
Isolated severe thunderstorm development is possible across middle
Texas coastal areas, parts of southeastern Louisiana and the western
Florida Panhandle Friday afternoon through Friday night.
...Discussion...
Latest model output offers little change concerning the forecast
evolution of the large-scale pattern through this period.
Substantive amplification within the split westerlies emanating from
the mid-latitude Pacific still appears probable Friday through
Friday night, including building ridging at mid-levels along an axis
west of 140W longitude into northwestern British Columbia, and on a larger-scale eastward across the Canadian Prairies and northern U.S.
Rockies. Within the larger-scale ridging, a modest mid-level
trough and developing embedded low are forecast to slowly dig to the
west of the U.S. Pacific coast. At the same time, broad upper
ridging may gradually build across the subtropical eastern Pacific
toward Baja California.
Downstream, a confluent regime will be maintained across
and east of the Rockies, and likely become enhanced at mid-levels
across the southern Great Plains through lower Mississippi Valley,
as short wave troughing digs to the southwest of an elongated area
of lower heights slowly shifting eastward through the
Ontario/Quebec/Great Lakes and Northeast vicinity.
A short wave perturbation reaching the Texas Big Bend vicinity by
12Z Friday probably will undergo shearing as it progresses through
the confluence to the south of the digging trough. However, as a
reinforcing cool surge noses southward to the lee of the southern
Rockies, across and south/southeast of the Texas Big Bend, guidance
suggests that forcing for ascent may remain sufficient to support a
developing wave along a stalled frontal zone, across middle Texas
coastal areas through the eastern Gulf coast vicinity Friday
afternoon through Friday night.
...Middle Texas coastal plain through western Florida Panhandle...
Large-scale forcing for ascent, aided by warm advection along and to
the cool side of the surface front, may support a swath of mostly
weak thunderstorm activity across much of the Gulf into southern
Atlantic coast Friday through Friday night. Forecast soundings
continue to indicate thermodynamic profiles with little potential to
support severe hail and wind, except perhaps in immediate proximity
to the surface front. Warm elevated mixed-layer air, particularly
across parts of Deep South Texas, may tend to inhibit thunderstorm
initiation to the south of the front.
Based on latest model output, severe weather potential for this
period appears a bit more conditional, dependent upon both the
evolution of the surface wave and the degree of destabilization
along the frontal zone, which remain uncertain. However, it still
appears possible that strengthening deep-layer shear and forcing for
ascent near the frontal wave could support isolated supercell
development across the middle Texas coastal plain by Friday
afternoon, across southeastern Louisiana parishes by late Friday
evening, and into the western Florida Panhandle toward 12Z Saturday.
..Kerr.. 04/30/2026
$$
--- Scorpio BBS
* Origin: (618:250/6)
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From
Mike Powell@618:250/6 to
All on Sat May 2 14:11:00 2026
ACUS02 KWNS 020502
SWODY2
SPC AC 020501
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1201 AM CDT Sat May 02 2026
Valid 031200Z - 041200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF MISSOURI AND ILLINOIS...
...SUMMARY...
A few strong thunderstorms are possible across parts of
northern/central Missouri and central Illinois on Sunday.
...Lower MO/Mid-MS Valleys...
Moderate deep-layer northwesterly flow will overspread the region as
a series of shortwave impulses migrate through an upper trough
oriented over the Midwest and eastern U.S. Temperatures aloft will
be quite cold (around -20 C at 500 mb), resulting in steep midlevel
lapse rates across the Mid-MS Valley region. At the surface,
boundary layer moisture will remain limited in the wake of a prior
cold frontal passage, resulting in Gulf moisture remaining well
offshore. Most guidance suggests dewpoints in the 50s are possible
along a corridor ahead of a weak surface front. While low-level
moisture will be limited, steep midlevel lapse rates will foster
1000-2000 J/kg MLCAPE. Model guidance remains unclear with regard to
convective initiation, but heating into the 70s will allow for an
uncapped environment. While deep-layer flow will mostly remain
unidirectional, speed shear will support supercell wind profiles
with 35+ effective shear magnitudes and elongated hodographs.
While overall storm coverage may remain low, and the risk is
conditional, if storms develop, isolated large hail and locally
strong gusts will be possible during the afternoon and evening.
..Leitman.. 05/02/2026
$$
--- ScorpioBBS/QWK v0.32a (Linux/x86_64)
* Origin: Project Scorpio TEST (618:250/6)