Severe Thunderstorm Warning 16, NWS St. Louis, MO

825 
WWUS53 KLSX 241742
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
1242 PM CDT Sun Apr 24 2022

ILC135-241751-
/O.EXP.KLSX.SV.W.0016.000000T0000Z-220424T1745Z/
Montgomery IL-
1242 PM CDT Sun Apr 24 2022

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN MONTGOMERY COUNTY
WILL EXPIRE AT 1245 PM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

LAT...LON 3952 8970 3953 8966 3952 8953 3939 8953
TIME...MOT...LOC 1741Z 231DEG 33KT 3958 8945 

$$

19

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
645 AM CDT Sun Apr 24 2022

.SHORT TERM...  (Through Late Monday Afternoon)
Issued at 457 AM CDT Sun Apr 24 2022

Latest radar mosaic is showing scattered showers moving across parts
of central and northeast Missouri into west central Illinois. Latest
surface analysis is showing a cold front extending from a deep low
over the northern Plains down through Iowa into western Missouri.
The was also an outflow boundary from earlier thunderstorms that has
pushed out east of a Quincy to near Mexico to Jefferson City line.
The HREF is still showing that the cold front will slowly progress
southeast across the CWA through this evening as the upper low moves
from the northern Plains into southern Ontario.  Coverage of storms
are still expected to increase ahead of the front this afternoon
under the entrance region of an upper jet streak over the Great
Lakes.  Still looks like there will may be a small window for
isolated severe storms this afternoon into early this evening over
southeast Missouri and southwest Illinois where MUCAPEs will reach
up to 1000 J/kg and deep shear will be around 50 knots.  The front
will continue to move south tonight and another shortwave trough
will move into the area late tonight.  With PWATS between 1.5-1.7"
and potential for some training, still can't rule out the potential
for some locally heavy rainfall over parts of southeast Missouri
into southwest Illinois. Showers and thunderstorms will linger
over the southern part of the CWA into early Monday morning before
the shortwave trough moves east of the area and subsidence sets
in bringing dry weather the rest of the day on Monday.

Cooler weather is expected today with the clouds, rain, and the
front moving through the area.  Highs are still expected to be above
normal at St. Louis.  With a cloudy start and cold air advection
behind the front, highs on Monday will be below normal.

Britt

.LONG TERM...  (Monday Night through Saturday)
Issued at 457 AM CDT Sun Apr 24 2022

Majority of ensemble members still agree that the upper low over
the western Great Lakes will move off to the east at the same time
a ridge will amplify over the central CONUS mid-late week. A
large surface high will move across the Midwest Tuesday into
Wednesday which will help bring dry weather to the region before
southwest flow sets up on Wednesday night as the high moves off to
the east. Then there will be a chance of showers and thunderstorms
over the area Thursday into Friday as a warm front moves north
into Missouri and Illinois and stalls across the area. Some of
the ensemble members including the operational GFS/ECMWF are
showing weak shortwave troughs moving over the ridge which will
help enhance thunderstorm chances during this time frame. The
chance for rain will continue into Saturday as a upper trough and
attendant cold front moves into the region.

Temperatures on Tuesday will fall back below normal as 850mb
temperatures fall back into the 0 to +5C range. With the surface
high moving across the Midwest, will need to watch for the potential
for a frost over parts of the area on Tuesday and possibly Wednesday
mornings. Temperatures will climb back to near normal on Wednesday
and Thursday and above normal on Friday and Saturday as 850mb
temperatures climb back into the 10-15C range. This is reflected
well in the GEFS and NBM temperature guidance, though the spread
increases with time which bring some uncertainty in the forecast
late in the week.

Britt

&&

.AVIATION...  (For the 12z TAFs through 12z Monday Morning)
Issued at 638 AM CDT Sun Apr 24 2022

Showers and scattered thunderstorms area expected to affect the
KUIN/KJEF/KCOU through 19-23Z and the St. Louis area terminals
through 06Z. The heavier showers and thunderstorms will produce
MVFR, possible IFR visibilities and ceilings at times. Southerly
winds will turn out of the northwest behind a cold front tonight.

Britt

&&

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

WFO LSX

Hazardous Weather Outlook
National Weather Service Saint Louis MO
402 AM CDT Sun Apr 24 2022

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-250915-
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-Saint Francois MO-Saint Louis City MO-Saint Louis MO-
Sainte Genevieve MO-Shelby MO-Warren MO-Washington IL-Washington MO-
402 AM CDT Sun Apr 24 2022

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.

There is a chance of thunderstorms through tonight. Isolated storms
this afternoon could produce strong wind gusts and marginally severe
hail over southeast Missouri and southwest Illinois. Locally heavy
rainfall is possible over southeast Missouri into southwest Illinois
tonight.

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

There is a chance for thunderstorms across parts of the area early
Monday morning and again Thursday night through Saturday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation maybe needed on a limited basis this afternoon.

Britt