Area Forecast Discussion
National Weather Service Columbia SC
313 PM EST Mon Jan 20 2025
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
Key Message(s):
- Very cold temperatures continue through the short term.
- Winter storm remains on track to affect the region Tuesday late
afternoon/evening.
- Winter Weather Advisory issued for the eastern Midlands.
Did I mention forecasting winter weather is so much fun?!?!?!?!
Anyway, one thing we remain highly confident about is the cold air
for Tuesday into Wednesday as arctic air continues to filter in from
the northwest. Afternoon highs are expected to be around 20 degrees
below normal for both days. Wednesday`s highs will be partially
dependent on any snow cover from the expected winter system.
Overnight temps are expected to drop into the upper teens to lower
20s, but winds are expected to stay elevated causing wind chills in
the lower teens or single digits at times. Due to the cold temps
during the day and frigid temps overnight, we have extended the
Cold Weather Advisory until 10 am on Wednesday.
Now, for the "fun" part. Almost all of the 12z guidance has shifted
the upcoming storm track back to the north and west a bit as well,
which has led to an uptick in snow amounts for the forecast area.
Another trend some guidance has been showing is possibly an earlier
onset of the snowfall for the forecast area, which seems reasonable
given models don`t typically handle initial warm air advection
precipitation well with these systems. The most likely onset time
remains in the 3-8 pm time period, however. It still looks like a
quick moving system, however, and is likely out of the area before
dawn. A limiting factor continues to be some dry air in the lower
levels, which could limit snow totals. A change with the latest
hires guidance is that the lower levels do moisten up for areas
south of the I-20 corridor, so confidence has increased for
accumulating snow for those areas. Confidence is highest for around
an inch of snow in the eastern Midlands, so we`ve issued a Winter
Weather Advisory for those areas. Still expecting a sharp gradient
between accumulating snow and no snow, but uncertainty remains in
exactly where that gradient will wind up. We`ll continue to monitor
model trends to determine additional changes to forecast amounts and
if an expansion of the Winter Weather Advisory will be needed. As
we`ve been mentioned, the lingering cold air will likely cause any
snow on the ground to stick around a little longer than typical for
the area.
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