Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 232351

551 PM CST MON NOV 23 2015

.SHORT TERM:  (Through Late Tonight)
Issued at 218 PM CST Mon Nov 23 2015

Expect clear skies tonight as surface ridge moves eastward
over the area. Winds will be light and temps will drop into the
upper 20`s to mid 30`s due to radiational cooling.


.LONG TERM:  (Tuesday through Next Monday)
Issued at 218 PM CST Mon Nov 23 2015

(Tuesday through Thanksgiving night)
Dry conditions persist through Tuesday as upper level ridge
continues to move across the area. Weak shortwave begins to move
over the area Tuesday night into Wednesday morning.This weak
shortwave provides enough ascent and moisture to warrant a slight
chance of showers to the area on Wednesday. Northern steam upper
level trough moves over the Great Lakes on Thursday and brings
with it a cold front that should begin to move through the area
Thursday morning. Moisture transport and ascent associated with
frontal passage warrant categorical and likely PoPs over the area
on Thursday and Thursday night.

(Friday through Monday)

GFS and ECMWF are similar during this period, though the ECMWF is
showing slightly better overall continuity, so have leaned toward
it for this forecast. Northern stream upper trough will move
through the Great Lakes on Friday dragging the cold front through
Missouri and Illinois with it. While the front will move south of
the area, the persistent upper southwesterly flow will keep a
chance of rain/snow going over the southern parts of Missouri and
Illinois going into Saturday. Then the ECMWF shows the western
CONUS upper low moving quickly eastward Sunday with it opening up
as a trough over Missouri and Illinois next Monday. The GFS is
slower with it`s solution and keeps the upper low intact as it
moves east early next week. This uncertainty between the models
lowers the overall confidence in next weekends forecast. Either
way, both solutions suggest the need to keep a chance of rain or
snow going areawide Sunday and Monday.

Will keep temperatures below normal behind the front given the
expected clouds and precipitation and 850mb temperatures in the 0 to
-5C range.



.AVIATION:  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 549 PM CST Mon Nov 23 2015

High pressure over the region overnight with a clear sky and light
and variable wind. Some fog may develop in valleys but not
confident enough to put in any TAFs. Light southeast wind develops
Tuesday as the high pressure area slides east.

Specifics for KSTL: VFR with light wind overnight becomign
southeast Tuesday.





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