Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 klsx 112341 

Area forecast discussion...updated aviation
National Weather Service Saint Louis MO
541 PM CST Mon Nov 11 2019

Short term... (through late Tuesday night)
issued at 235 PM CST Mon Nov 11 2019

System that is bringing a decent first snowfall to the entire
forecast area is slowly winding down. Will keep headlines as is
with far western portions of advisory expiring at 3 PM, with
remainder of advisory expiring between 6 PM and 9 PM.

As for additional snowfall accumulations through early this evening,
will see less than an inch for areas along and west of a Litchfield
to St. Louis to Steelville, MO line with higher amounts to the east.
Storm totals will be between 1 and 3 inches with locally higher
amounts possible.

The snow should taper off everywhere by 9 PM with strong surface
ridge building in and clear skies prevailing. This will usher in the
coldest air of the season so far with near record lows tonight in
the 9 to 13 degree range. Another issue will be the gusty north
winds, which will diminish a bit tonight but will create wind
chill indices between zero and 5 below.

On Tuesday, despite plenty of sunshine and light north winds,
temperatures will only rise into the low to mid 20s for highs.

Another cold night Tuesday night with lows in the teens.


Long term... (wednesday through next monday)
issued at 235 PM CST Mon Nov 11 2019

Surface ridge will be moving off to the east on Wednesday with
southerly winds returning to the region. So temperatures will
moderate a bit with highs in the low 30s to low 40s, which is still
15 to 20 degrees below normal for this time of year.

In the meantime, with active northwest flow aloft, will see next
system approach the area with cold front moving through Wednesday
night. However, with limited moisture return and main energy staying
to the north of forecast area, frontal passage will be a dry one
with just an increase in mid and high clouds. Not a lot of cold air advection with
this system, so highs on Thursday will actually be a bit higher than
on Wednesday, in the upper 30s to mid 40s.

Another ridge of high pressure will build into the region once again
for the last part of the work week and into the weekend. Beyond that
extended models have some differences on timing of next system.
Highs through the remainder of the extended will be in the 40s to
low 50s.



Aviation... (for the 00z tafs through 00z Tuesday evening)
issued at 529 PM CST Mon Nov 11 2019

The snow that has fallen over the area today has cleared all the
terminals and is continuing to move southeast out of the area. The
back edge of the stratus deck and associated MVFR conditions has
moved out of KUIN and kcou and is moving southeast, expecting to
clear the St. Louis Metro terminals by 2-4z. Scattered VFR
stratocumulus is dissipating behind the main stratus deck but
could linger across the area.

Sustained northwest winds in the low to mid teens and gusts in
the low 20s will continue during the overnight hours, weakening
with day break tomorrow.

Specifics for kstl:

VFR conditions are expected to return to kstl as the back edge of
the stratus deck is expected to clear the terminal around 3z.
Northwest winds in the mid-teens and gusts in the low 20s will
continue until 12z, diminishing afterwards.



issued at 346 am CST Mon Nov 11 2019

Today's snowfall, followed by brutally cold air, could challenge
records today and tomorrow. Below is a list of records that have
best potential to be challenged:

November 11th
record snowfall | record snow depth
St. Louis 1.0 set in 1911 1 set in 1995
Columbia 0.4 set in 1995 1 set in 1995
Quincy *** ***

November 12th
record low temp | record low Max | record snow depth
St. Louis 12 set in 1911 20 set in 1911 T set in 1995
Columbia 9 set in 1911 17 set in 1911 1 set in 1911
Quincy 10 set in 1986 28 set in 2014 ***

***no official snowfall records for quincy***


Preliminary point temps/pops...
Saint Louis 12 24 18 37 / 10 0 0 0
Quincy 9 23 15 37 / 0 0 0 5
Columbia 9 24 16 41 / 5 0 0 0
Jefferson City 10 25 16 42 / 5 0 0 0
Salem 12 23 14 34 / 90 0 0 0
Farmington 11 24 13 37 / 100 0 0 0


Lsx watches/warnings/advisories...
MO...Winter Weather Advisory until 9 PM CST this evening for Crawford
MO-Iron MO-Madison MO-Reynolds MO-Saint Francois MO-Sainte
Genevieve MO-Washington MO.

Winter Weather Advisory until 6 PM CST this evening for Franklin
MO-Gasconade MO-Jefferson MO-Lincoln MO-Montgomery MO-Osage
MO-Saint Charles MO-Saint Louis City MO-Saint Louis MO-
Warren MO.

Illinois...Winter Weather Advisory until 9 PM CST this evening for Clinton
Illinois-Fayette Illinois-Marion Illinois-Randolph Illinois-Washington Illinois.

Winter Weather Advisory until 6 PM CST this evening for Bond Illinois-
Calhoun Illinois-Greene Illinois-Jersey Illinois-Macoupin Illinois-Madison Illinois-
Monroe Illinois-Montgomery Illinois-Saint Clair Illinois.


National Weather Service Glossary of Abbreviations