SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK
1130 AM CDT Sat Aug 01 2020 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE OHIO VALLEY AND MID-ATLANTIC... ...SUMMARY...
Scattered damaging winds and a brief tornado are possible, centered
on portions of the Upper Ohio Valley into northern Virginia from
mid-afternoon through this evening. ...Ohio Valley east to central/northern Virginia...
A surface low was located near the KY/IL border and should lift
northward into western OH tonight. As a broad upper-level trough
amplifies today, an increase in low/mid-level wind fields will
result in shear profiles supportive of multicells and a couple
supercells across the Ohio Valley and mid-Atlantic region. An
increase in storm coverage/intensity is expected by early-mid
afternoon across northern KY/southern OH vicinity along a nearly
stationary front, while a second area of severe storms should
develop over eastern WV/northern VA by late afternoon. Damaging
winds will be the primary risk though a tornado or two cannot be
ruled out, especially east of the surface low where low-level flow
will be more favorable. A cluster of storms is also expected over eastern portions of NC/SC,
aided in part by a remnant outflow boundary and strong instability. Weak wind fields will limit storm organization, but wet downbursts
capable of isolated strong wind gusts will be possible. ...New Mexico/southeast Arizona/far West Texas...
A belt of enhanced mid-level northerlies will lie across the central/eastern portions of the area between upper-level high centered over the Lower CO Valley and a trough near the MS Valley. Buoyancy will be slightly lower compared to yesterday due to a drier
boundary-layer. Nevertheless, weak MLCAPE should contribute to a
couple updrafts with mid-level rotation off the Sangre de Cristo and
Sacramento Mountains with a risk for isolated severe hail.
Otherwise, the steep lapse rate environment will contribute to a
risk for locally severe wind gusts with isolated to scattered storms
that should peak in the late afternoon to early evening. ...East-central FL Coast...
Hurricane Isaias continues moving steadily northwest toward the FL Atlantic Coast. The more favorable shear profiles supportive of a
risk of tornadoes should remain offshore through 12z Sunday. ..Bunting/Karstens.. 08/01/2020