Hmmm... updated morning discussion sounds intriguing for this afternoon and evening
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1035 AM EDT Wed Jul 28 2021
.SYNOPSIS...
A weak front stalled in the region today will be the focus of a
few showers and thunderstorms this afternoon. A much stronger
front later Thursday and Thursday night will result in more
widespread showers and storms. High pressure will return Friday
and linger into the weekend, with cooler and drier air taking
hold. Another system may approach early next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
Mid-morning update: Current visible satellite imagery shows
mostly sunny skies across the area, allowing strong daytime
heating to occur. 12z IAD sounding shows steeper than climo
mid-level lapse rates (6.5 C/km) and lots of dry air in the
mid- upper levels. With strong daytime heating occurring, low-
level lapse rates are expected to become very steep as well
(exceeding 9.5 C/km). The sounding shows 1164 J/kg of DCAPE
prior to daytime heating, and that value should only increase.
The combination of steep low-level lapse rates, better than
climo mid-level lapse rates, high DCAPE, and decent flow in the
mid- levels suggests that damaging winds could be a threat with
any storms this afternoon. Can`t rule out an instance or two of
large hail with any stronger storms either, given the better
than climo mid- level lapse rates, ample dry air in the mid-
levels, and decent shear through a deep layer. In the absence
of stronger forcing for ascent both aloft and at the surface,
the smaller details with respect to placement and timing of
storms remain a bit up in the air. We`ll continue to monitor
trends through the remainder of the day.