|
|
Categorical Day2 1730Z Outlook
|
|
Probability of severe weather within 25 miles of a point.
Hatched Area: 10% or greater probability of significant severe weather within 25 miles of a point.
|
|
|
Images courtesy of the NWS Storm Prediction Center
000
ACUS02 KWNS 181657
SWODY2
SPC AC 181655
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 AM CDT Thu Apr 18 2024
Valid 191200Z - 201200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
SOUTHEAST TOWARD THE CAROLINA PIEDMONT...
...SUMMARY...
Sporadic strong to marginally severe storms are still possible
tomorrow (Friday) over parts of the Southeast.
...Synopsis...
A broad mid-level trough will traverse Ontario and Quebec, with
mainly zonal flow overspreading the central and northern CONUS
tomorrow (Friday). Meanwhile, a smaller mid-level trough is poised
to eject into the southern High Plains at the end of the period. A
surface cold front will sweep across the eastern U.S. in advance of
the first mid-level trough, providing enough low-level ascent to
support scattered strong thunderstorm development given adequate
buoyancy and vertical wind shear preceding the front. For Friday
night into Saturday morning, the approach of the southwestern
mid-level trough will encourage low-level jet development over the
southern Plains, with scattered to widespread thunderstorm
development expected along the low-level jet terminus, where
low-level convergence will be strongest.
...Parts of the Southeast toward the Carolina Piedmont...
Surface temperatures are expected to warm above 80 F amid low to mid
60s F dewpoints ahead of the surface cold front, boosting SBCAPE
from 1000-2000 J/kg across the warm sector. Modest westerly 500 mb
flow from the glancing mid-level trough will overspread a 15-20 kt
southwesterly 850 mb wind field, resulting in elongated hodographs
and 40+ kts of effective bulk shear. As such, organized multicells
and transient supercells are expected to initiate ahead of the cold
front by afternoon, accompanied by occasional instances of hail and
gusty winds. A couple instances of severe hail/wind could occur with
some of the stronger storms, especially if a more pronounced
supercell structure can become established.
...Central and northern Texas...
A strongly capped boundary layer is expected to reside across much
of TX through the period, limiting the chances for surface-based
convective initiation. As the low level jet strengthens overnight,
the jet terminus is expected to become situated somewhere near the
Red River, where isentropic ascent should lift elevated buoyant
parcels to their LFC and initiate scattered to potentially numerous
thunderstorms. LFCs are expected to be between 700-600 mb, which
should restrict CAPE to thin profiles, limiting severe hail
production. Nonetheless, given elongated hodographs and steep
mid-level lapse rates, at least small hail is possible and a sparse
instance of severe hail cannot be ruled out, though the coverage
seems too isolated/localized to warrant probabilities at this time.
..Squitieri.. 04/18/2024
$$
