MD 1871 CONCERNING TORNADO WATCH 615… FOR MIDDLE ATLANTIC
Mesoscale Discussion 1871
NWS Storm Prediction Center Norman OK
1004 PM CDT Thu Aug 08 2024
Areas affected…Middle Atlantic
Concerning…Tornado Watch 615…
Valid 090304Z – 090500Z
The severe weather threat for Tornado Watch 615 continues.
SUMMARY…Severe threat will gradually spread into extreme southern
Pennsylvania over the next several hours. However, this threat will
be limited by weaker buoyancy.
DISCUSSION…Tropical warm sector is gradually advancing north
across the Delmarva, per mid 70s surface dew points approaching
southeast PA. Latest diagnostic data suggests a fairly well-defined
boundary extends from central NJ-extreme southeast PA-northern VA.
Low-level shear has also increased at CCX where 0-3km SRH is now
around 350 m2/s2. Strongest updrafts have been confined to the
tropical warm sector and this will likely continue as buoyancy is
quite limited north of the boundary. Given the poor lapse rates, it
appears mid 70s dew points may be necessary for robust, longer-lived
updrafts. If/until this air mass spreads north, confidence is not
particularly high enough to warrant a new tornado watch. However,
will continue to monitor this transition zone for recovery north of
ww615.
..Darrow.. 08/09/2024
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…PHI…CTP…LWX…
LAT…LON 39717828 40157663 40057569 39487574 39137695 38977813
39717828
