Flash Flood Warning 53, NWS St. Louis, MO

787 
WGUS73 KLSX 011640
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
1140 AM CDT Sun Sep 1 2019

ILC135-011650-
/O.CAN.KLSX.FF.W.0053.000000T0000Z-190901T1730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Montgomery IL-
1140 AM CDT Sun Sep 1 2019

...THE FLASH FLOOD WARNING FOR NORTHWESTERN MONTGOMERY COUNTY IS
CANCELLED...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 3934 8970 3952 8970 3952 8954 3934 8953

$$

Byrd

Area Forecast Discussion
National Weather Service Saint Louis MO
347 AM CDT Sun Sep 1 2019

.SHORT TERM...  (Through Late Monday Afternoon)
Issued at 346 AM CDT Sun Sep 1 2019

Upper level trof continues to move east and support showers with a
few thunderstorms early this morning. Expect showers to gradually
end from west to east this morning, then linger across eastern and
southeastern portions of the CWA as the trailing trof interacts with
the surface front. Expect clouds to be slow to break up and clear
out of the region this afternoon. Have therefore trended cooler for
temps today.

As the trof exits the region, a weak surface ridge builds into the
area this evening and overnight. With ample low level moisture and
weak surface winds, believe at least patches of fog will develop
tonight.

Temperatures moderate on Monday as weak southerly flow returns to
the area and an upper ridge begins to build into the region.

Tilly

.LONG TERM...  (Monday Night through Saturday)
Issued at 346 AM CDT Sun Sep 1 2019

Period begins with heights falling ever so slightly as a trof
approaches the Upper Midwest. Thermal ridge builds into the area on
Tuesday ahead of a cold front. Model solns differ with 850mb temps
ahead of this front with the GFS and NAM at the warmer end of the
spectrum. Regardless, the entire CWA should see high temps in the
upper 80s to lower 90s. This may still be too cool considering the
setup. Given the 500mb heights across the region and what should be
a largely cloud free day, have trended toward the warmer guidance
for Tues.

Models continue to depict a cold front sweeping through the CWA Tues
night. With very warm low level temps along and ahead of this front,
the region will remain capped. However, some models suggest enough
cooling behind the front that elevated convection will be possible.
This cooling seems to be a result of an active convective scheme
rather than CAA. Regardless, a threat for some elevated convection
remains Tues night although seems to be a low threat at this time.

Behind the front, a surface ridge builds into the region with a
reinforcing cold front Thurs night. This will keep temps much cooler
and drier conditions through the end of the week.

Tilly

&&

.AVIATION...  (For the 06z TAFs through 06z Sunday Night)
Issued at 1154 PM CDT Sat Aug 31 2019

Spotty showers and maybe a few thunderstorms can be expected
overnight into the early morning hours. Have some showers at KUIN
but just VCSH elsewhere given the low expected coverage.
Otherwise still expecting stratus currently over central and
northeast MO to expand eastward overnight encompassing the St.
Louis terminals and KUIN. Flight conditions overnight with the
stratus should trend towards IFR. IFR flight conditions are then
expected to persist Sunday morning with improvement to MVFR
nearing midday, and then VFR on Sunday afternoon.

SPECIFICS FOR KSTL:

Spotty showers can be expected overnight into the early morning
hours. Have just VCSH mentioned due to the low expected coverage.
Otherwise still expecting stratus currently over central and
northeast MO to expand eastward overnight into KSTL. Flight
with the stratus should trend towards IFR. IFR flight conditions
are then expected to persist Sunday morning with improvement to
MVFR nearing midday, and then VFR on Sunday afternoon.

Glass

&&

.PRELIMINARY POINT TEMPS/POPS...
Saint Louis     83  68  87  70 /  20   5   0   0
Quincy          80  64  85  70 /  20   0   0   0
Columbia        81  63  86  68 /  10   0   0   0
Jefferson City  82  63  86  68 /  10   0   0   0
Salem           83  63  85  67 /  20   5   0   0
Farmington      82  63  85  65 /  20   5   0   0

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

WFO LSX

Hazardous Weather Outlook
National Weather Service Saint Louis MO
435 AM CDT Sun Sep 1 2019

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-021200-
Adams IL-Audrain MO-Bond IL-Boone MO-Brown IL-Calhoun IL-Callaway MO-
Clinton IL-Cole MO-Crawford MO-Fayette IL-Franklin MO-Gasconade MO-
Greene IL-Iron MO-Jefferson MO-Jersey IL-Knox MO-Lewis MO-Lincoln MO-
Macoupin IL-Madison IL-Madison MO-Marion IL-Marion MO-Moniteau MO-
Monroe IL-Monroe MO-Montgomery IL-Montgomery MO-Osage MO-Pike IL-
Pike MO-Ralls MO-Randolph IL-Reynolds MO-Saint Charles MO-
Saint Clair IL-Saint Francois MO-Saint Louis City MO-Saint Louis MO-
Sainte Genevieve MO-Shelby MO-Warren MO-Washington IL-Washington MO-
435 AM CDT Sun Sep 1 2019

This Hazardous Weather Outlook is for portions of eastern and
central Missouri as well as west central and southwest Illinois.

.DAY ONE...Today and tonight.

Isolated thunderstorms are possible for mainly southwest Illinois
through this afternoon.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

There is a chance of thunderstorms Tuesday night for portions of
northeast Missouri and west-central Illinois.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated through tonight.

Tilly