Flash Flood Warning 15, NWS St. Louis, MO

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1102 PM CDT Sat Jun 1 2019

.SHORT TERM...  (Through Late Tonight)
Issued at 329 PM CDT Sat Jun 1 2019

Thunderstorms have finally started to develop near a cold front
which was poised to move through the region. There is also a pre-
frontal trough across the area which could provide an additional
focus for SHRA/TSRA development.

Now that the storms have started to develop, the updrafts are
strengthening rapidly. These storms were developing in an
environment characterized by little cloud cover (read: ample
insolation), CAPE values around 2000 J/kg, H7-H5 lapse rates of
6.5-7 deg C/km, and around 30-40 kts of 0-6km shear. BUFKIT
soundings suggest that large hail is the primary threat,
especially with any rotating storms. Clusters of storms would also
pose a damaging wind threat. SHRA/TSRA should simultaneously shift
southeastward and decrease in coverage through late evening.

There is some uncertainty regarding the southern extent of the
severe weather threat prior to 06z. Storms will be moving towards
the southeast, but instability will wane with the loss of daytime
heating.

Overnight lows should be around 60 degrees, which is similar to
last night and near seasonal normals.

Kanofsky

.LONG TERM...  (Sunday through Next Saturday)
Issued at 329 PM CDT Sat Jun 1 2019

A building ridge to the west and a deepening trough to the east
will place the LSX CWA beneath northwest flow aloft for Sunday and
Sunday night. With no upper disturbances and a drier post-frontal
air mass in place, dry weather is expected during this time. Highs
will be in the mid/upper 70s, which is several degrees below
normal for this time of year. Overnight lows will be in the 50s,
which is also below normal for this time of year. Radiational
cooling may allow some spots to cool a bit lower than currently
forecast.

By Monday, the surface high pressure center over the Great Lakes will
gradually shift southeastward towards the Ohio Valley while the
upper ridge axis also begins to shift eastward and de-amplify.
Highs will remain below average on Monday due to the influence of
the high pressure center which will have suppressed the cold front
farther to the south. Monday should be dry across most of the LSX
CWA, but parts of central MO will be near a sharpening baroclinic
zone and isolated SHRA/TSRA cannot be entirely ruled out.

After the upper ridge axis shifts eastward, model solutions
depict a slow-moving upper low over the southwestern CONUS which
eventually lifts northeastward during the week. This will bring
several potential periods of SHRA/TSRA to the region between
Tuesday and next Saturday.

Kanofsky

&&

.AVIATION...  (For the 06z TAFs through 06z Sunday Night)
Issued at 1054 PM CDT Sat Jun 1 2019

Cold front near UIN will move southeastward through COU and the St
Louis metro area late tonight. Southwest surface winds will veer
around to a northwest direction after fropa. Scattered showers and
storms just ahead of this front should be south of the taf sites
by 06Z Sunday, with the sky clearing out late tonight. A north-
northwest surface wind can be expected on Sunday with little if
any cloudiness as a surface ridge moves southeastward into
northern MO.

SPECIFICS FOR KSTL: Cold front near UIN will move southeastward
through STL late tonight. Southwest surface winds will veer
around to a northwest direction after fropa. Scattered showers and
storms just ahead of this front should be south of STL by 06Z
Sunday, with the sky clearing out late tonight. A north-northwest
surface wind can be expected on Sunday with little if any
cloudiness as a surface ridge moves southeastward into northern
MO.

GKS

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Flash Flood Watch through Sunday evening for Lewis MO-Marion MO.

IL...None.
&&

WFO LSX

Hazardous Weather Outlook
National Weather Service Saint Louis MO
421 PM CDT Sat Jun 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>075-084-085-099-021230-
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-
421 PM CDT Sat Jun 1 2019

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

.DAY ONE...Tonight.

Thunderstorms have developed this afternoon near a cold front. Some
of the storms may be severe and capable of producing large hail up
to the size of golf balls as well as damaging winds of 60 mph or
greater.

Major flooding is ongoing along many rivers, including main stem
rivers and some tributaries.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a chance for thunderstorms across parts of the area from
Monday night through Friday.

Major flooding will continue along many rivers, including main stem
rivers and some tributaries.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed through this evening across
parts of Missouri and Illinois.

Kanofsky

Special Weather Statement
National Weather Service St Louis MO
938 PM CDT Sat Jun 1 2019

ILZ079-102-020315-
Randolph IL-Monroe IL-
938 PM CDT Sat Jun 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN MONROE AND NORTHERN
RANDOLPH COUNTIES UNTIL 1015 PM CDT...

At 938 PM CDT, Doppler radar was tracking a strong thunderstorm over
Red Bud, moving southeast at 20 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations impacted include...
Sparta, Red Bud, Evansville, Baldwin, Preston, Prairie, Ellis Grove,
Ruma, Houston, Walsh, Renault, Ames and New Palestine.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
southwestern Illinois.

LAT...LON 3794 8983 3814 9016 3829 9005 3825 8991
      3824 8990 3822 8990 3822 8982 3818 8969
TIME...MOT...LOC 0238Z 300DEG 16KT 3818 9003

Britt

Special Weather Statement
National Weather Service St Louis MO
1012 PM CDT Sat Jun 1 2019

ILZ100-101-MOZ061-063-064-020400-
St. Clair IL-Madison IL-St. Louis MO-St. Charles MO-
St. Louis City MO-
1012 PM CDT Sat Jun 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN MADISON AND
NORTHWESTERN ST. CLAIR COUNTIES IN SOUTHWESTERN ILLINOIS...CENTRAL
ST. CHARLES AND NORTHEASTERN ST. LOUIS COUNTIES IN EAST CENTRAL
MISSOURI AND ST. LOUIS CITY UNTIL 1100 PM CDT...

At 1012 PM CDT, Doppler radar was tracking a strong thunderstorm over
St. Ann, moving southeast at 45 mph.

Wind gusts up to 50 mph will be possible with this storm.

Locations impacted include...
St. Louis, St. Charles, Florissant, Chesterfield, Belleville,
University City, Granite City, O'Fallon, Maryland Heights, East St.
Louis, Hazelwood, Collinsville, Webster Groves, Ferguson, Creve
Coeur, Fairview Heights, Overland, Clayton, Cahokia and Jennings.

This includes the following highways...
 Interstate 64 in Illinois between exits 9 and 19.
 Interstate 70 in Missouri between exits 229 and 231.

This also includes Scott Joplin Historic Site, First Missouri State
Capitol Historic Site, and Horseshoe Lake State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
southwestern Illinois...and east central Missouri.

LAT...LON 3870 9056 3886 9045 3865 8981 3838 8997
TIME...MOT...LOC 0312Z 298DEG 40KT 3874 9041

Tilly

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
1022 PM CDT SAT JUN 1 2019

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

1015 PM     HAIL             5 W UNION               38.45N 91.10W
06/01/2019  M0.25 INCH       FRANKLIN           MO   TRAINED SPOTTER

&&

BRITT

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
1028 PM CDT SAT JUN 1 2019

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

1020 PM     HAIL             BLOOMSDALE              38.02N 90.22W
06/01/2019  E0.70 INCH       STE. GENEVIEVE     MO   TRAINED SPOTTER

&&

GKS

Special Weather Statement
National Weather Service St Louis MO
1137 PM CDT Sat Jun 1 2019

MOZ073>075-084-085-099-020515-
Reynolds MO-Madison MO-Washington MO-Iron MO-St. Francois MO-
Ste. Genevieve MO-
1137 PM CDT Sat Jun 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR IRON...SOUTHWESTERN STE.
GENEVIEVE...NORTHEASTERN REYNOLDS AND MADISON COUNTIES IN
SOUTHEASTERN MISSOURI...SOUTHEASTERN WASHINGTON COUNTY IN EAST
CENTRAL MISSOURI AND ST. FRANCOIS COUNTIES IN SOUTHEASTERN MISSOURI
UNTIL 1215 AM CDT...

At 1136 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from Desloge to near Belleview. Movement was
southeast at 45 mph.

Penny size hail and wind gusts up to 50 mph will be possible with
these storms.

Locations impacted include...
Farmington, Bonne Terre, Desloge, Fredericktown, Bismarck, Ironton,
Leadwood, Park Hills, Pilot Knob, Iron Mountain Lake, Arcadia,
Irondale, Annapolis, Junction City, Cobalt, Marquand, Knob Lick, Iron
Mountain, Buckhorn and Glover.

This also includes St. Joe State Park, Fort Davidson Historic Site,
Elephant Rocks State Park, Taum Sauk Mountain State Park, and
Missouri Mines Historic Site.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3770 9093 3798 9047 3765 9014 3731 9014
      3732 9055 3727 9055 3727 9074 3723 9074
TIME...MOT...LOC 0436Z 328DEG 38KT 3790 9051 3770 9083

Britt

Special Weather Statement
National Weather Service St Louis MO
1213 AM CDT Sun Jun 2 2019

MOZ074-085-020545-
Madison MO-St. Francois MO-
1213 AM CDT Sun Jun 2 2019

...SIGNIFICANT WEATHER ADVISORY FOR MADISON AND SOUTHEASTERN ST.
FRANCOIS COUNTIES IN SOUTHEASTERN MISSOURI UNTIL 1245 AM CDT...

At 1213 AM CDT, Doppler radar was tracking a strong thunderstorm over
Cobalt, moving southeast at 45 mph.

Wind gusts up to 50 mph will be possible with this storm.

Locations impacted include...
Fredericktown, Junction City, Cobalt, Marquand, Buckhorn, Roselle,
Saco, Mine La Motte, Libertyville and Catherine Place.

LAT...LON 3732 9055 3760 9055 3760 9053 3762 9053
      3764 9040 3777 9032 3767 9020 3769 9016
      3766 9012 3764 9015 3755 9014 3731 9014
TIME...MOT...LOC 0513Z 312DEG 39KT 3755 9024

Maples