Severe Thunderstorm Warning 39, NWS St. Louis, MO

486 
WWUS53 KLSX 010105
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
805 PM CDT Fri Mar 31 2023

MOC099-010115-
/O.CAN.KLSX.SV.W.0039.000000T0000Z-230401T0130Z/
Jefferson MO-
805 PM CDT Fri Mar 31 2023

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL JEFFERSON COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1000 PM CDT for southwestern
Illinois...and east central Missouri.

LAT...LON 3822 8971 3822 9036 3828 9037 3834 9037
      3838 9035 3841 9031 3851 8971
TIME...MOT...LOC 0105Z 262DEG 29KT 3835 9024 

$$

ILC133-163-010130-
/O.CON.KLSX.SV.W.0039.000000T0000Z-230401T0130Z/
Monroe IL-St. Clair IL-
805 PM CDT Fri Mar 31 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR MONROE AND SOUTHERN ST. CLAIR COUNTIES...

At 805 PM CDT, a severe thunderstorm was located over Fountain,
moving east at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
  Waterloo, New Design, Smithton, Freeburg, New Athens and 
  Mascoutah.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1000 PM CDT for southwestern
Illinois...and east central Missouri.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3822 8971 3822 9036 3828 9037 3834 9037
      3838 9035 3841 9031 3851 8971
TIME...MOT...LOC 0105Z 262DEG 29KT 3835 9024 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Glass

649 
WWUS53 KLSX 010120
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
820 PM CDT Fri Mar 31 2023

ILC133-163-010130-
/O.EXP.KLSX.SV.W.0039.000000T0000Z-230401T0130Z/
Monroe IL-St. Clair IL-
820 PM CDT Fri Mar 31 2023

...THE SEVERE THUNDERSTORM WARNING FOR MONROE AND SOUTHERN ST. CLAIR
COUNTIES WILL EXPIRE AT 830 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 1000 PM CDT for southwestern
Illinois.

LAT...LON 3822 8971 3822 9036 3828 9037 3834 9037
      3838 9035 3841 9031 3851 8971
TIME...MOT...LOC 0120Z 256DEG 59KT 3841 8995 

$$

Glass

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
631 PM CDT Fri Mar 31 2023

.UPDATE...
Issued at 625 PM CDT Fri Mar 31 2023

Upgraded Wind Advisory for areas along and north of a Boone,
Callaway, Audrain, Pike and Pike IL line to a High Wind Warning
through 02z Saturday. Reports of 50+kt wind gusts with frontal
passage in this area. Then gusty winds will persist through
tomorrow.

Byrd
&&

.SHORT TERM...  (Through Late Saturday Night)
Issued at 234 PM CDT Fri Mar 31 2023

As of 2PM, we were beginning to see more in the way of surface
based instability spreading across the entire forecast area as the
best moisture just ahead of the front is pushing into our area.
With a very strong wind field, especially aloft, we continue to
expect severe thunderstorms to develop ahead of the front as it
moves east this afternoon and evening. All severe hazards will be
possible, including large hail. However, the greatest threats will
likely be from damaging winds and tornadoes. Storms will be fast
moving and exit the area early this evening.

Winds shift to the southwest behind the initial front, with a
secondary front (with actual cold air behind it) bringing a shift
to westerly winds during the overnight. This secondary front
brings the cold advection which will aid in low level mixing and
transporting the higher winds from aloft down toward the surface
in the form of strong wind gusts. The Wind Advisory continues into
midday Saturday across the northern half of the area where the
potential for gusts over 45 MPH is highest. It will turn much
colder as well, especially considering the widespread 70+
temperatures we've seen today. Tomorrow will top out only in the
50s. Winds decrease in the second half of the day as the low
pressure system continues to pull away to the east. Temperatures
fall off into the 30s tonight.

Kimble

.LONG TERM...  (Sunday through Next Friday)
Issued at 234 PM CDT Fri Mar 31 2023

The colder conditions don't last long. We quickly transition
toward upper level ridging by early next week. Surface high
pressure shifting to the east will allow a southerly low level
flow to return on Sunday with the temperature warming back into
the 60s to low 70s.

Another trough digs into the western US on Monday, with its
primary trough axis moving out into the Plains on Tuesday. The
southerly flow ahead of the trough will reintroduce moisture out
into the Plains and set the stage for another round of strong to
severe thunderstorms. How exactly this pans out is still
uncertain, but there's been better agreement on the timing with
the latest model runs than there has been in prior days. The
threat for our area seems centered on late Tuesday into Tuesday
night. There's significant instability and shear available, with
supercells the likely storm mode and all severe weather types
possible. One concern is the timing of the trough with the best
forcing for storms coming through overnight when surface based
instability may be harder to come by.

Showers and storms may begin as early as Monday as a warm front
sets up across our area, so the best chance of showers and storms
will be along and north of the front in the northern half of the
forecast area. Storms in this environment would be elevated, and
any severe weather threat should be limited to hail. It's Tuesday
when the best chance of surface based instability across the
entire are exists, and thus the greatest chance of severe weather.
This is consistent with the SPC Day 5 outlook.

NBM hangs on to POP on Wednesday, but we believe with the growing
consensus on timing that the shower and thunderstorm threat will
be ending quickly early Wednesday morning the threat being during
the night, surface based instability may be harder to come by
during the period of stronger forcing. So while all severe weather
threats are possible, the threat for our area may lean more
toward large hail and perhaps some damaging wind gusts if storms
are no longer surface based when they arrive.ing. Future runs of
the NBM will likely pull back on POP Wednesday as our area will
largely be behind a cold front at that point. Temperatures ahead
of the front on Tuesday are likely to soar into the 80s which
contributes to the greater instability potential. Behind the front
we drop down into the 50s again through Thursday.

Kimble
&&

.AVIATION...  (For the 00z TAFs through 00z Saturday Evening)
Issued at 630 PM CDT Fri Mar 31 2023

Main area of showers and storms have exited the TAF sites except
STL metro area, so kept vicinity thunderstorm mention at these
sites through 01z Saturday. Otherwise, main issue will be the
winds. South to southwest winds will veer to the west to northwest
on backside of cold front. Gusts will persist through midday, then
gradually diminish during the afternoon hours on Saturday. Will
see some SC wrap around the back side of system with ceilings
lowering to MVFR at KUIN between 10z and 19z Saturday. Rest of
sites will remain VFR.

Byrd
&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Wind Advisory until 1 PM CDT Saturday for Cole MO-Franklin MO-
     Gasconade MO-Jefferson MO-Lincoln MO-Moniteau MO-Montgomery
     MO-Osage MO-Saint Charles MO-Saint Louis City MO-Saint
     Louis MO-Warren MO.

     Wind Advisory until 1 AM CDT Saturday for Crawford MO-Iron MO-
     Madison MO-Reynolds MO-Saint Francois MO-Sainte Genevieve
     MO-Washington MO.

     High Wind Warning until 9 PM CDT this evening for Audrain MO-
     Boone MO-Callaway MO-Knox MO-Lewis MO-Marion MO-Monroe MO-
     Pike MO-Ralls MO-Shelby MO.

IL...Wind Advisory until 1 PM CDT Saturday for Bond IL-Calhoun IL-
     Clinton IL-Fayette IL-Greene IL-Jersey IL-Macoupin IL-
     Madison IL-Marion IL-Monroe IL-Montgomery IL-Saint Clair IL-
     Washington IL.

     Wind Advisory until 1 AM CDT Saturday for Randolph IL.

     High Wind Warning until 9 PM CDT this evening for Adams IL-Brown
     IL-Pike IL.

&&

WFO LSX

Hazardous Weather Outlook
National Weather Service St Louis MO
413 AM CDT Fri Mar 31 2023

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-011200-
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Adams IL-Brown IL-Pike IL-
Calhoun IL-Jersey IL-Madison IL-Saint Clair IL-Monroe IL-Knox MO-
Lewis MO-Shelby MO-Marion MO-Monroe MO-Ralls MO-Pike MO-Boone MO-
Audrain MO-Moniteau MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-
Lincoln MO-Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-
Saint Louis MO-Saint Louis City MO-Jefferson MO-Crawford MO-
Washington MO-Saint Francois MO-Sainte Genevieve MO-Iron MO-
Madison MO-Reynolds MO-
413 AM CDT Fri Mar 31 2023

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.

Thunderstorms are expected across most of the area today...mainly
this afternoon and evening. Some of the thunderstorms this afternoon
and evening may be severe with damaging winds, large hail, and
possible tornadoes.

Winds this afternoon will gust as high as 50 mph at times. Please see
the Wind Advisory for more information.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Winds on Saturday will continue to gust up to 50 mph at
times...mainly along and north of the Missouri River, as well as
along and north of Interstate 64 in Illinois. Please see the Wind
Advisory for more information.

There is a chance of thunderstorms across portions of the area again
Sunday night through Tuesday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed this afternoon and evening.

Carney

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
723 PM CDT FRI MAR 31 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0430 PM     HAIL             VANDALIA                39.31N 91.49W
03/31/2023  E1.50 INCH       AUDRAIN            MO   PUBLIC

&&

BRC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
726 PM CDT FRI MAR 31 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0722 PM     HAIL             GRUBVILLE               38.29N 90.75W
03/31/2023  M0.25 INCH       JEFFERSON          MO   TRAINED SPOTTER

&&

MMG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
727 PM CDT FRI MAR 31 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0618 PM     HAIL             LADDONIA                39.24N 91.64W
03/31/2023  E1.75 INCH       AUDRAIN            MO   PUBLIC

&&

BRC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
733 PM CDT FRI MAR 31 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0731 PM     TSTM WND GST     2 E MAPLEWOOD           38.61N 90.28W
03/31/2023  E50 MPH          ST. LOUIS CITY     MO   TRAINED SPOTTER

&&

MMG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
734 PM CDT FRI MAR 31 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0732 PM     HAIL             1 SSE CRESTWOOD         38.54N 90.37W
03/31/2023  M0.70 INCH       ST. LOUIS          MO   TRAINED SPOTTER

            DIME SIZE HAIL AND WIND GUSTS ESTIMATED NEAR
            40 MPH.

&&

MAPLES

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
735 PM CDT FRI MAR 31 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0733 PM     HAIL             WEBSTER GROVES          38.59N 90.35W
03/31/2023  M0.25 INCH       ST. LOUIS          MO   TRAINED SPOTTER

&&

MMG