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fxus63 klsx 130454 

Area forecast discussion...updated aviation
National Weather Service Saint Louis MO
1054 PM CST Tue Nov 12 2019

Short term... (through late tonight)
issued at 234 PM CST Tue Nov 12 2019

Quiet weather is expected tonight with mostly clear skies and one
more night of unseasonably cold temperatures. Overnight lows are
expected to fall into the teens and upper single digits, which is
20-25 degrees colder than average. As a high pressure center over
the region shifts eastward tonight, initially northwesterly winds
will gradually back and become nearly southerly by daybreak.


Long term... (wednesday through next tuesday)
issued at 234 PM CST Tue Nov 12 2019

Warm air advection associated with southerly winds will help
daily high temperatures reach the mid-30s to lower 40s on Wed. The
pressure gradient will also be tightening across the region ahead
of an approaching trough axis, and this should produce breezy
conditions during the day with gusts up to 25 mph possible.

A weak low pressure system and its associated cold front will
move through the region on Wed night into Thu. The reinforcing
cold air is not nearly as cold as the recent Arctic air mass which
has been affecting the region. This means that highs on Thu
should be similar to what they will have been on Wed. Overnight
lows on Wed night (mid/upper 20s) and Thu night (upper teens to
lower 20s) will be similar to each other, but Thu night looks a
few degrees colder due to the cold frontal passage and the
presence of a 1030 hpa surface high pressure center and the
associated ridge axis stretching across the area. A gradual
warming trend is expected through the weekend, and the forecast
highs/lows are expected to be within a few degrees of normal by
early next week.

Overall, there appear to be very few opportunities for
precipitation over the next several days. The upper air pattern
during this period features broadly northwest flow aloft with the
passage of a few pv anomalies and their associated trough axes,
first on Wed night/Thu and then again on Sunday night/Mon.
Moisture appears limited with both of these features, and the best
dynamics should be south of the lsx County Warning Area on Sunday night/Mon.
Therefore, an increase in cloud cover is the most that is
currently expected from these systems.



Aviation... (for the 06z tafs through 06z Wednesday night)
issued at 1050 PM CST Tue Nov 12 2019

VFR conditions will prevail through the period. Several rounds of
high clouds will be moving in and out of the terminals over the
next 24-36 hours. Winds have become south-southeasterly and will
begin to increase in speed with daybreak tomorrow. Sustained winds
will peak in the low teens with gusts reaching into the low 20s.



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