Discussion 11/21/2023 7:00 AM
Drizzle and fog early this morning:
In the wake of a cold front, reduced visibilities due to
intermittent drizzle and fog are currently ongoing across the CWA.
Current radar and model trends depicting no cloud ice, upslope
flow across the plateau, and saturated low-levels suggest that
the drizzle and fog will last through 8AM or so with the fog
lingering a bit longer than the drizzle. Even when the fog
dissipates, though, low clouds will continue through the day.
Breezy conditions and cold air advection will also occur today as
the cold front continues pushing SE and the pressure gradient
tightens on the backside of the surface low. Sustained NW winds
between 15-20 mph are possible in some locations with gusts up to
25-30 mph.
During the afternoon, a few quick and narrow bands of
rain will move through.
Clouds and cold air advection through the day will keep high
temperatures today in the upper 40s and drop lows tonight into the
upper 20s, especially as skies clear and winds diminish after
midnight.
Warming trend up to Thanksgiving:
Quickly after the upper-level trough departs, surface high
pressure will move into the area underneath strong left entrance
jet streak dynamics. Despite being under northwesterly flow, a
pronounced mid and upper-level ridge over the western CONUS will
transport warmer air eastward. Strong northerly WAA is evident in
the 850-mb layer along its ridge axis, bumping up the 850-mb
temperatures in our region to 4-8C by Wednesday afternoon. Thus,
will be slightly warmer Wednesday around 50F. However, with clear
skies and 50F only being near the 25th percentile of climatology
for Springfield with 4-8C 850-mb temps, it would not be surprising
to see highs outperform 50F by a degree or two. Lows will also
slightly increase to the lower 30s Wednesday night.
Southerly surface flow will briefly return Thursday as the low-
level ridge axis shifts east of our region. This will promote a
mild warm-up for Thanksgiving Day with highs in the upper 50s
underneath sunny skies. It`s certainly looking to be nice weather
for Turkey Day.
Cooler once again after Thanksgiving and into the weekend:
The relatively warm air won`t last long, though, as the tail-end
of a cold front is expected to dive through the region sometime
Friday. Current timing has it across our CWA during the day
Friday, so highs could range anywhere between 45 and 55F depending
on if it moves through faster or slower than expected.
Nevertheless, after the frontal passage, the weekend highs look to
be in the mid-40s with lows dropping to the mid-20s by
Sunday/Monday night.
Increasing precipitation chances this weekend:
Precipitation chances through Friday are low (like <10% low). But
PoPs are increasing for a system to move through over the weekend
as models are beginning to agree that a shortwave trough will
move through the area. Current chances are at 30-40% with mostly
rain in the forecast. Snow will not be out of the question, but
would need to see a much colder push in temperatures to have
increasing confidence in that message.