Area Forecast Discussion
Issued by NWS St. Louis, MO

Current Version | Previous Version | Text Only | 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 44 45 46 47 48 49 50

000
FXUS63 KLSX 152228
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
528 PM CDT Sat Jun 15 2019

.SHORT TERM...  (Through Late Sunday Night)
Issued at 348 PM CDT Sat Jun 15 2019

MCV is making it`s way out of the forecast area as of 20z with some
lingering showers and a few storms. In the meantime, the clouds are
beginning to scatter out from west to east. CAMs are indicating MU
CAPEs in excess of 3000 J/kg and mid level lapse rates around 7.4
degC/km between now and 00z Sunday. So if the atmosphere is able
to recover, there are plenty of old outflow boundaries around to
trigger more activity, so kept slight chance/chance pops through
the early evening hours.

Otherwise, increasing chances of showers and storms expected this
evening and through the overnight hours as main cold front begins to
sink south across the forecast area. With increasing low level
moisture on nose of low level jet, MCS development expected over
southern IA/northern MO this evening, then track to the southeast
across forecast area. Could see a few strong to severe storms with
it with the main threats being large hail and damaging winds.
Heaviest rains still appear to be over portions of west central and
southwestern Illinois, so kept Flash Flood Watch going til 7 am
Sunday.

Showers and storms will taper off through the morning hours on
Sunday. However with residual outflow boundaries and slowly
sinking cold front, will see redevelopment mainly along and south
of I-70 by Sunday afternoon. There is a marginal risk of strong to
severe storms, especially Sunday afternoon.

Storms will taper off once again through Sunday evening, but with
frontal boundary lingering over the region, will keep chance pops
going through the overnight hours.

Byrd

.LONG TERM...  (Monday through Next Saturday)
Issued at 348 PM CDT Sat Jun 15 2019

Active weather patter will persist through most of next week. Models
remain in agreement with the front stalling over the area through
at least next Friday with several rounds of activity through this
period. This wet pattern will keep the potential for another 1-3
inches of rainfall through next Friday. Otherwise, temperatures
will remain at or just bit below normal for this time of year.

Byrd

&&

.AVIATION...  (For the 00z TAFs through 00z Sunday Evening)
Issued at 500 PM CDT Sat Jun 15 2019

A cold front will drop slowly southeastward into our area late
tonight and Sunday. This front may make it to near UIN and COU by
18Z Sunday. A complex of thunderstorms is expected to develop
later this evening ahead of a weak upper level disturbance, just
south of this front, and on the nose of a southwesterly low level
jet. Thunderstorms may move into UIN by 03Z, into COU around
03-04Z, and into the St Louis metro area around 05-06Z Sunday. The
convection should shift south-southeast of the taf sites by
10-12Z Sunday. Thunderstorms may redevelop by late Sunday
afternoon from COU to STL. Prevailing VFR conditions are expected
outside of the showers/storms. Surface winds should be southwesterly
outside of the storms, except the wind will become west-
northwesterly in UIN Sunday afternoon.

SPECIFICS FOR KSTL: A cold front will drop slowly southeastward into
our area late tonight and Sunday. This front may make it to near
UIN and COU by 18Z Sunday. A complex of thunderstorms is expected
to develop later this evening ahead of a weak upper level
disturbance, just south of this front, and on the nose of a
southwesterly low level jet. Thunderstorms may move into STL
around 05-06Z Sunday. The convection should shift south-southeast
of STL by 10-12Z Sunday. Thunderstorms may redevelop by late
Sunday afternoon from COU to STL. Prevailing VFR conditions are
expected outside of the showers/storms. Surface winds should be
southwesterly outside of the storms.

GKS

&&

.PRELIMINARY POINT TEMPS/POPS...
Saint Louis     69  86  68  81 /  80  60  60  50
Quincy          68  84  65  80 /  70  20  40  30
Columbia        67  82  64  81 /  80  50  50  50
Jefferson City  67  84  64  82 /  80  60  50  50
Salem           69  86  67  82 /  90  70  60  60
Farmington      67  85  64  81 /  80  60  60  70

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...Flash Flood Watch through Sunday morning for Bond IL-Fayette IL-
     Greene IL-Jersey IL-Macoupin IL-Montgomery IL.

&&

$$

WFO LSX


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