SPC AC 061921
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0121 PM CST Thu Feb 06 2025
Valid 081200Z - 091200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Aside from low probabilities for scattered thunderstorm development
across parts of the Ohio Valley, the risk for thunderstorms appears
negligible across much of the U.S., Saturday through Saturday night.
...Discussion...
Models indicate that mid-level flow will begin to undergo
amplification across the northern mid-latitudes of the eastern
Pacific into western North America, including building mid-level
ridging across the northeastern Pacific through Alaska and digging
downstream troughing east of the Canadian Rockies. Otherwise, it
appears that there will be little change across much of the
contiguous U.S., with ridging centered over the subtropical
latitudes maintaining an influence across much of the southern into
central tier states. Within a broadly confluent, zonal regime
across the northern tier, a couple of embedded short wave
perturbations may consolidate into larger-scale, but still
low-amplitude, troughing progressing across the Great Lakes vicinity
into Northeast by late Saturday night.
It appears that the evolving mid-level trough may provide support
for increasingly significant surface cyclogenesis offshore of the
northern Mid Atlantic coast by the end of the period. This is
likely to be focused along a tightening baroclinic zone, near the
eroding southern periphery of a seasonably cold air mass entrenched
to the east of the Rockies. Initially stalled across parts of the
southern Great Plains into Ohio Valley and southern Mid Atlantic,
the surface frontal zone is forecast to advance southward into the
Gulf Coast states Saturday through Saturday night, in the wake of
the wave.
...Lower Ohio Valley...
Model differences concerning the frontal wave development, and
potential boundary-layer destabilization, along the eroding shallow
southern periphery of the cold air across the interior U.S. remains
problematic concerning convective potential. Strengthening of
lower/mid-tropospheric wind fields and shear near the frontal wave
is likely to become conditionally supportive of severe weather
potential, given sufficient destabilization. However, regardless of
the boundary-layer modification (and the NAM may be too aggressive
with the lingering shallow sharp surface-based inversion across
Kentucky, east-northeast of Bowling Green into the Blue Grass by
late Saturday afternoon), there does appear a general consensus that
relatively warm, dry air at mid-levels may tend to suppress
destabilization. At least some convection, perhaps mostly elevated
near and north of the Ohio River, may become capable of producing
lightning. But the risk for severe weather still appears negligible
at this time.
..Kerr.. 02/06/2025
CLICK TO GET WUUS03 PTSDY3 PRODUCT
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0830Z
|