Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 290554

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1154 PM CST Mon Nov 28 2016

.SHORT TERM...  (Through Late Tuesday Afternoon)
Issued at 322 PM CST Mon Nov 28 2016

Rainfall over the eastern 1/3 of the CWFA will be ending from west to
east this evening as the "cold" front passes and drier air filters
into the area.  Clouds are likewise clearing from west to east, but
are not moving out quite as fast as expected.  Latest satellite pics
show the clearing line probably getting from central Missouri to the
St. Louis Metro area by 03-04Z...and then east to our CWFA border by
07-08Z.  The RAP seems to have a decent handle on the
have used it as the basis for my cloud forecast tonight.  South to
southwest flow tonight into Tuesday isn`t exactly a cold
only expecting lows in the 40s tonight.  Additionally there
should be a decent amount of insolation on Tuesday to go along with
the southerly flow.  MOS looks reasonable with highs well above
normal again in the upper 50s to mid 60s.


.LONG TERM...  (Tuesday Night through Next Monday)
Issued at 322 PM CST Mon Nov 28 2016

(Wednesday through Friday)

Still expect Wednesday through Saturday to be mainly dry.  Both the
GFS and ECMWF are in good agreement that the upper low that will be
over the Upper Midwest on Wednesday morning will lift northeastward
through the Great Lakes and not bring any precipitation to the area.
In the meantime, zonal upper flow will setup at least through Friday
before the ECWMF and GFS begin showing diverging solutions to the
forecast over the weekend.

With polar cold front staying well south of the area during the
period and 850mb temperature staying around -5C, GEFS mean temps
support temperatures staying around normal values.

(Saturday through next Monday)

There continues to be great uncertainty with the forecast over the
weekend into early next week as the the ECMWF and the GFS are
showing different solutions.  The GFS/GFS ensemble has shown more
continuity with bringing a northern stream trough across the area
Saturday night and Sunday which would bring some light rain/snow to
the area. The ECMWF on the other hand has not shown as much run to
run consistency, with it bringing out a larger, colder system over
the weekend that would have the potential to produce more snow.
Given the consistency of the GFS, will lean more toward it`s
solution at this point.  Temperatures will continue to be close to
normal during the period.



.AVIATION...  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1142 PM CST Mon Nov 28 2016

Skies have mainly cleared this evng across the area. Addtnl
stratus is expected to move into SE MO and sthrn IL out of NE AR
over the next several hours. Most guidance indicates that this
stratus will stretch from near KFAM NE to KENL by 12Z. CIGS across
SE MO and sthrn IL are low end MVFR but drop to IFR in NE AR.
Whatever stratus does dvlp should dsspt thru the mrng and be gone
by 18Z. Otherwise expect mid/high clouds and a Sthrly breeze aob
10 kts...becoming Wrly late in the period


VFR fcst thru the prd with Sthrly winds aob 10kts becoming Wrly
after 00Z Wed. Mid/high clouds are fcst to invade the region Tue
mrng from the SW. Stratus is expected to move into SE MO and
sthrn IL towards 12Z but all indications are that it should remainwell
SE of the terminal attm.





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