SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1223 PM CDT Fri Jul 14 2023
Valid 151200Z - 161200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
LOWER GREAT LAKES...OHIO AND TENNESSEE VALLEY REGIONS...AND OVER THE
SOUTHERN HIGH PLAINS...
...SUMMARY...
Scattered storms, a few producing damaging gusts, are possible from
the Lower Great Lakes across parts of the Ohio and Tennessee Valleys
toward the southern Appalachians. Isolated hail is also possible
late over the southern High Plains.
...Synopsis...
A deep upper low will remain over the Manitoba/Ontario area with a
broad area of cyclonic flow aloft over the northern Plains, Great
Lakes and Northeast. The southern periphery of the stronger flow
aloft will sweep east across the OH and TN Valleys during the day,
with a wave ejecting northeastward toward the Mid Atlantic
overnight. Winds around 850 mb will increase out of the south late
in the day and overnight ahead of the upper wave, enhancing
warm/moist advection and lift.
At the surface, a cold front will stretch roughly from OH into TN by
late afternoon, with dewpoints near 70 F. A warm front will also
lift northward overnight across PA and NY, aided by the stronger
flow off the surface. A surface low will develop over OH, and will
deepen a bit overnight into western NY.
...Lower Great Lakes southward into northern AL/GA/SC...
A morning MCS may affects parts of southern MO, western TN and KY
Saturday morning, and may provide a further focus for redevelopment
during the day and during the evening across TN, northern AL and GA.
Predictability is low for this scenario but ample moisture and
instability will be present to support a conditional wind threat in
this corridor, possibly extending into the western Carolinas
overnight.
During the day, areas of rain and storms will exist in association
with the upper trough and cold front, moving across IN, OH, KY, with
stronger activity possible during the diurnal cycle over OH and
eastern KY. Locally strong gusts or marginal hail will be possible
but neither CAPE nor shear will be very strong. During the evening,
low-level shear will increase as the low deepens and winds just off
the surface increase to over 30 kt. This will increase SRH, but at a
time when low-level instability will be minimized. Still, rising
dewpoints may yield SBCAPE sufficient for a few ongoing cells to
acquire rotation, with either enhanced wind gust potential or a
brief/weak tornado.
...Southeast CO...eastern NM...western TX Panhandle...
Low-level moisture will surge northwestward during the evening and
overnight from the TX Panhandle into NM and southeast CO, where a
steep lapse rate environment will remain. A few elevated cells
capable of large hail are forecast mainly after 03Z, moving
southeastward out of CO/NM and into the TX Panhandle through Sunday
morning.
..Jewell.. 07/14/2023
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