Area Forecast Discussion
Issued by NWS St. Louis, MO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43

FXUS63 KLSX 242316

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
616 PM CDT Sat Jun 24 2017

.SHORT TERM...  (Through Late Sunday Afternoon)
Issued at 235 PM CDT Sat Jun 24 2017

Weak cold front will quickly progress through the CWA overnight
tonight. Slight increase in midlevel cloudiness along with a wind
shift from the southwest ahead of the front back to the northwest
behind the boundary. With a mostly clear sky for most of the area
during a majority of the overnight hours and light winds in close
proximity to the front, lows tonight should be seasonably chilly as
temperatures bottom out in the low to upper 50s.

Sunday will be quite a similar day as today with a sunny or mostly
sunny sky and fairly brisk northwest winds. Expect high temperatures
to be in the upper 70s to low 80s, basically a persistence forecast.


.LONG TERM...  (Sunday Night through Next Saturday)
Issued at 235 PM CDT Sat Jun 24 2017

Somewhat amplified upper pattern that will be over the CONUS on
Sunday night will turn zonal by midweek as trough over the Great
Lakes moves off to the east and the ridge over the west coast
dampens out.  A surface high will move across Missouri on Sunday
night and early Monday causing winds to turn light.  There will be a
chance of showers and thunderstorms over the area late Monday into
Monday night as a shortwave trough moves across the area in
northwesterly flow aloft.  Tuesday through Thursday should be mostly
dry as the GFS/ECMWF are showing a ridge over the the southeast and
the cold front staying mainly north of the area.  By Friday and
Saturday, both models show the front moving slowly south through
Missouri and Illinois which will bring showers and thunderstorms
both days.

Temperatures will be below normal to start the week as 850mb
temperatures start out in the 7-10C range before climbing into
the 15-20C range by the end of the week. This falls in line well
with the GEFS mean values which show temperatures going from
below normal to near-above normal mid-late week.



.AVIATION...  (For the 00z TAFs through 00z Sunday Evening)
Issued at 612 PM CDT Sat Jun 24 2017

VFR flight conditions are expected to prevail across the area
through Sunday afternoon. Northwest flow will diminish this
evening and briefly turn more southwesterly later tonight. Another
reinforcing cold front will move through the area Sunday morning
which will turn the wind back to the northwest. Northwest wind
will likely become gusty at times Sunday afternoon.


VFR flight conditions will prevail at Lambert through Sunday
evening. Northwest wind will diminish this evening and then back
to the southwest between 03-05Z. A second cold front will move
through the terminal Sunday morning which will turn the wind back
around to the northwest. Wind will likely become gusty again
during the afternoon before calming down again in the evening.





WFO LSX is the U.S. government's official web portal to all federal, state and local government web resources and services.