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fxus63 klsx 172030 

Area forecast discussion
National Weather Service Saint Louis MO
330 PM CDT Mon Jun 17 2019

Short term... (through late Tuesday night)
issued at 327 PM CDT Mon Jun 17 2019

Showers and storms will begin to diminish early this evening with
loss of daytime heating and shortwave exiting region. In the
meantime, there is still the potential for locally heavy rainfall,
especially from Jefferson City through the St. Louis Metro area to
just north of Salem Illinois. So will keep Flash Flood Watch in
effect until 06z Tuesday for areas along and south of Interstate 70.

Kept slight chance pops for southern portions of forecast area from
late tonight through the day on Tuesday in proximity to the stalled
cold front. Otherwise, most locations will be dry. Lows tonight will
be in the 60s with highs on Tuesday in the low to mid 80s.

By Tuesday night, more significant upper level shortwave will slide
southeast towards region with increasing chances of showers and
storms over portions of central and northeast Missouri after 06z


Long term... (wednesday through next monday)
issued at 327 PM CDT Mon Jun 17 2019

Wednesday will be the wettest day this week, as strongest of a
series of shortwaves slides through along the stalled frontal
boundary. Decent instability, shear and plenty of low level moisture
will make for a mix of strong to severe storms as well as areas of
locally heavy rainfall Wednesday afternoon and evening.

System will exit region late Wednesday night with drier conditions
expected on Thursday. Otherwise, extended models begin to have
differences in timing and strength with several waves of activity
expected through early next week. Temperatures will remain a bit
below normal through Thursday, before warming up a bit above normal
for remainder of forecast period.


Aviation... (for the 18z tafs through 18z Tuesday afternoon)
issued at 1230 PM CDT Mon Jun 17 2019

With front stalled across the forecast area, MVFR ceilings remain
over all taf sites. However, ceilings should lift to VFR by 20z-
22z. Otherwise, main issue in the short term is the showers and
storms that will persist through sunset before diminishing. Late
tonight, ceilings will lower back down to MVFR with patchy fog
developing as well. By mid morning on Tuesday, fog should
dissipate. Light and variable winds will persist through the
forecast period.

Specifics for kstl:
complex of showers and storms will remain anchored over the St.
Louis Metro area through the afternoon hours. So MVFR flight
conditions will persist before improving to VFR by 00z Tuesday.
Otherwise, will see patchy fog and MVFR ceilings develop late
tonight. Expect light and variable winds through the entire
forecast period.


Preliminary point temps/pops...
Saint Louis 66 83 67 81 / 70 20 30 80
Quincy 62 81 66 76 / 10 10 50 80
Columbia 63 82 66 78 / 30 10 70 80
Jefferson City 64 83 66 81 / 50 20 70 80
Salem 66 82 64 82 / 70 20 20 80
Farmington 64 82 63 82 / 60 20 20 80


Lsx watches/warnings/advisories...
MO...Flash Flood Watch until 1 am CDT Tuesday for Cole MO-Crawford MO-
Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Madison MO-
Moniteau MO-Osage MO-Reynolds MO-Saint Charles MO-Saint
Francois MO-Saint Louis City MO-Saint Louis MO-Sainte
Genevieve MO-Warren MO-Washington MO.

Illinois...Flash Flood Watch until 1 am CDT Tuesday for Bond Illinois-Clinton Illinois-
Fayette Illinois-Madison Illinois-Marion Illinois-Monroe Illinois-Randolph Illinois-Saint
Clair Illinois-Washington Illinois.

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