D.C.-area forecast: From a winter chill today to springlike storms possible Sunday

[nitpicked]

1. From the latest NWS forecast

https://forecast.weather.gov/product.php?site=LWX&issuedby=LWX&product=AFD&format=CI&version=1&glossary=1&highlight=off

(snip)
.LONG TERM /SATURDAY THROUGH TUESDAY/...
On Saturday, upper level ridging will be moving off the East
Coast as a trough digs into the Plains. Surface high pressure
to our south continues advancing offshore with southerly flow
behind it advecting moisture and above normal temperatures into
the region. Dry conditions are expected most of Saturday with
rain chances moving into our western periphery Saturday night as
surface low pressure moves into the Ohio Valley.

Guidance remains in decent agreement synoptically with the next
significant weather maker on Sunday, amplifying the upper trough as
it moves into the Midwest with the base of the trough digging down
into the Mississippi Valley. There are some notable timing
differences, with the GFS jogging slightly ahead of the ECMWF and
Canadian. The suite of guidance seems to have trended slightly
slower overall though, the jet moving overhead later in the
afternoon/early evening. Ensemble members continue to introduce some
modest CAPE around this time, though the more favorable shear might
be later in the evening/overnight. Probs for 24hr 1" rainfall have
continued to increase as well.

This far out, there is significant uncertainty, but we will continue
to monitor for the potential severe/heavy rain threat. Strong winds
may also accompany this system. Timing will be key in whether these
threats materialize. For now, our area can at least anticipate a
soaking rain.

After the system exits, high pressure is expected to build in behind
it Monday into Tuesday, with some possible upslope precipitation
along the Alleghenies.
(snip)