Alert archive / Missouri / Flash Flood Watches in 2017

Flash Flood Watch 1, NWS St. Louis, MO

April 27, 201725 counties in Missouri; 15 counties in Illinois

NWS St. Louis, MO issued this flash flood watch at Apr 27, 2017, 4:29 AM CDT for 25 counties in Missouri; 15 counties in Illinois. It took effect at Apr 28, 2017, 7:00 PM CDT. It was in force for 51 hr.

The area

The counties it named.

The facts

Issued
Apr 27, 2017, 4:29 AM CDT (09:29 UTC)
In effect from
Apr 28, 2017, 7:00 PM CDT
Expired
Apr 30, 2017, 9:31 PM CDT
In force
51 hr
Issued by
NWS St. Louis, MO
Flood severity
None
All 40 counties

Bond County, IL, Calhoun County, IL, Clinton County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Lincoln County, MO, Madison County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 6 km from the middle of the area, began a volume at 09:28 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 9.5 hours before the alert went out and 246 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2017-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2017-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 213 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
848 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
213 m²/s²
0-3 km storm-relative helicity
317 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

200 
WGUS63 KLSX 270929
FFALSX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Saint Louis MO
429 AM CDT Thu Apr 27 2017

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-272130-
/O.NEW.KLSX.FF.A.0001.170429T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Alton, Edwardsville, Belleville, Cahokia, 
Bowling Green, Columbia, Mexico, Jefferson City, Fulton, 
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
429 AM CDT Thu Apr 27 2017

...FLASH FLOOD WATCH IN EFFECT FROM FRIDAY EVENING THROUGH LATE
SUNDAY NIGHT...

The National Weather Service in Saint Louis has issued a

* Flash Flood Watch for portions of Illinois and Missouri... 
  including the following counties...in Illinois...Bond IL... 
  Calhoun IL...Clinton IL...Fayette IL...Greene IL...Jersey IL...
   Macoupin IL...Madison IL...Marion IL...Monroe IL...Montgomery 
  IL...Randolph IL...Saint Clair IL and Washington IL. In 
  Missouri...Audrain MO...Boone MO...Callaway MO...Cole MO... 
  Crawford MO...Franklin MO...Gasconade MO...Iron MO...Jefferson 
  MO...Lincoln MO...Madison MO...Moniteau MO...Montgomery MO... 
  Osage MO...Pike MO...Reynolds MO...Saint Charles MO...Saint 
  Francois MO...Saint Louis City MO...Saint Louis MO...Sainte 
  Genevieve MO...Warren MO and Washington MO. 

* from Friday evening through Sunday evening

* Rainfall totals of 1 to 3 inches over the past 24 hours has set
  the stage for a significant flooding event this weekend. A slow
  moving potent storm system will interact with a very moist
  airmass to produce heavy rainfall over the weekend. Forecast
  rainfall totals of 2 to 5 inches are likely with higher amounts
  possible across southeastern Missouri and southern Illinois. 

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Significant rises on larger 
  streams and rivers will also be possible. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

2%
8 follow-up statements
236 
WGUS63 KLSX 272052
FFALSX

Flood Watch
National Weather Service Saint Louis MO
352 PM CDT Thu Apr 27 2017

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-281030-
/O.CON.KLSX.FF.A.0001.170429T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Alton, Edwardsville, Belleville, Cahokia, 
Bowling Green, Columbia, Mexico, Jefferson City, Fulton, 
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
352 PM CDT Thu Apr 27 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM FRIDAY EVENING
THROUGH LATE SUNDAY NIGHT...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Randolph IL... 
  Saint Clair IL and Washington IL. In Missouri...Audrain MO... 
  Boone MO...Callaway MO...Cole MO...Crawford MO...Franklin MO...
   Gasconade MO...Iron MO...Jefferson MO...Lincoln MO...Madison 
  MO...Moniteau MO...Montgomery MO...Osage MO...Pike MO... 
  Reynolds MO...Saint Charles MO...Saint Francois MO...Saint 
  Louis City MO...Saint Louis MO...Sainte Genevieve MO...Warren 
  MO and Washington MO. 

* from Friday evening through late Sunday night

* Recent rainfall has has set the stage for a significant flooding
  event this weekend. A slow moving and potent storm system will
  interact with a very moist airmass to produce heavy rainfall
  over the weekend. Rainfall totals of 2 to 5 inches are likely
  with locally higher amounts possible across southeastern
  Missouri and southern Illinois. 

* Heavy rainfall will result in flooding of low lying or poor
  drainage areas...and ultimately dangerous flash flooding on
  smaller creeks and streams. Moderate to major flooding is also
  possible on larger streams and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

Carney
030 
WGUS63 KLSX 280934
FFALSX

Flood Watch
National Weather Service Saint Louis MO
434 AM CDT Fri Apr 28 2017

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-282145-
/O.CON.KLSX.FF.A.0001.170429T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Alton, Edwardsville, Belleville, Cahokia, 
Bowling Green, Columbia, Mexico, Jefferson City, Fulton, 
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
434 AM CDT Fri Apr 28 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM THIS EVENING THROUGH
LATE SUNDAY NIGHT...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Randolph IL... 
  Saint Clair IL and Washington IL. In Missouri...Audrain MO... 
  Boone MO...Callaway MO...Cole MO...Crawford MO...Franklin MO...
   Gasconade MO...Iron MO...Jefferson MO...Lincoln MO...Madison 
  MO...Moniteau MO...Montgomery MO...Osage MO...Pike MO... 
  Reynolds MO...Saint Charles MO...Saint Francois MO...Saint 
  Louis City MO...Saint Louis MO...Sainte Genevieve MO...Warren 
  MO and Washington MO. 

* from this evening through late Sunday night

* Recent rainfall has set the stage for a significant flooding
  event this weekend. A slow moving and potent storm system will
  interact with a very moist airmass to produce heavy rainfall
  over the weekend. Rainfall totals of 3 to 5 inches are likely
  with locally higher amounts possible across southeastern
  Missouri and southern Illinois. 

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Moderate to major flooding is also 
  possible on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

GKS
471 
WGUS63 KLSX 282002
FFALSX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Saint Louis MO
302 PM CDT Fri Apr 28 2017


ILZ097-MOZ034-035-291000-
/O.EXA.KLSX.FF.A.0001.170429T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pike IL-Monroe MO-Ralls MO-
Including the city of Pittsfield
302 PM CDT Fri Apr 28 2017

...FLASH FLOOD WATCH IN EFFECT FROM 7 PM CDT THIS EVENING THROUGH
LATE SUNDAY NIGHT...

The National Weather Service in Saint Louis has expanded the

* Flash Flood Watch to include portions of west central Illinois 
  and northeast Missouri...including the following counties...in 
  west central Illinois...Pike IL. In northeast Missouri... 
  Monroe MO and Ralls MO. 

* from 7 PM CDT this evening through late Sunday night

* Recent rainfall has set the stage for a significant flooding
  event this weekend. A slow moving and potent storm system will
  interact with a very moist airmass to produce heavy rainfall
  over the weekend. Rainfall totals of 3 to 5 inches are likely. 

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Moderate to major flooding is also 
  possible on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-291000-
/O.CON.KLSX.FF.A.0001.170429T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Alton, Edwardsville, Belleville, Cahokia, 
Bowling Green, Columbia, Mexico, Jefferson City, Fulton, 
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
302 PM CDT Fri Apr 28 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 7 PM CDT THIS EVENING
THROUGH LATE SUNDAY NIGHT...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Randolph IL... 
  Saint Clair IL and Washington IL. In Missouri...Audrain MO... 
  Boone MO...Callaway MO...Cole MO...Crawford MO...Franklin MO...
   Gasconade MO...Iron MO...Jefferson MO...Lincoln MO...Madison 
  MO...Moniteau MO...Montgomery MO...Osage MO...Pike MO... 
  Reynolds MO...Saint Charles MO...Saint Francois MO...Saint 
  Louis City MO...Saint Louis MO...Sainte Genevieve MO...Warren 
  MO and Washington MO. 

* from 7 PM CDT this evening through late Sunday night

* Recent rainfall has set the stage for a significant flooding
  event this weekend. A slow moving and potent storm system will
  interact with a very moist airmass to produce heavy rainfall
  over the weekend. Rainfall totals of 3 to 5 inches are likely
  with locally higher amounts possible along Interstate 44
  corridor in Missouri and Interstate 55 corridor in Illinois.

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Moderate to major flooding is also 
  possible on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

Byrd
630 
WGUS63 KLSX 290940
FFALSX

Flood Watch
National Weather Service Saint Louis MO
440 AM CDT Sat Apr 29 2017

ILZ058>060-064-065-069-070-074-079-097>102-MOZ034>036-041-042-
047>052-059>065-072>075-084-085-099-292145-
/O.CON.KLSX.FF.A.0001.000000T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Pike IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Pittsfield, Alton, Edwardsville, Belleville, 
Cahokia, Bowling Green, Columbia, Mexico, Jefferson City, Fulton,
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
440 AM CDT Sat Apr 29 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SUNDAY
NIGHT...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Pike IL... 
  Randolph IL...Saint Clair IL and Washington IL. In Missouri... 
  Audrain MO...Boone MO...Callaway MO...Cole MO...Crawford MO... 
  Franklin MO...Gasconade MO...Iron MO...Jefferson MO...Lincoln 
  MO...Madison MO...Moniteau MO...Monroe MO...Montgomery MO... 
  Osage MO...Pike MO...Ralls MO...Reynolds MO...Saint Charles 
  MO...Saint Francois MO...Saint Louis City MO...Saint Louis 
  MO...Sainte Genevieve MO...Warren MO and Washington MO. 

* through late Sunday night

* Recent rainfall has set the stage for a significant flooding 
  event this weekend. A slow moving and potent storm system will 
  interact with a very moist airmass to produce heavy rainfall 
  over the weekend. Rainfall totals of 3 to 5 inches are likely 
  with locally higher amounts possible along the Interstate 44 
  corridor in Missouri and Interstate 55 corridor in Illinois. 

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Moderate to major flooding is also 
  possible on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

GKS
810 
WGUS63 KLSX 292107
FFALSX

Flood Watch
National Weather Service Saint Louis MO
407 PM CDT Sat Apr 29 2017


ILZ058>060-064-065-069-070-074-079-097>102-MOZ034>036-041-042-
047>052-059>065-072>075-084-085-099-301000-
/O.CON.KLSX.FF.A.0001.000000T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Pike IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Pittsfield, Alton, Edwardsville, Belleville, 
Cahokia, Bowling Green, Columbia, Mexico, Jefferson City, Fulton,
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
407 PM CDT Sat Apr 29 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SUNDAY
NIGHT...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Pike IL... 
  Randolph IL...Saint Clair IL and Washington IL. In Missouri... 
  Audrain MO...Boone MO...Callaway MO...Cole MO...Crawford MO... 
  Franklin MO...Gasconade MO...Iron MO...Jefferson MO...Lincoln 
  MO...Madison MO...Moniteau MO...Monroe MO...Montgomery MO... 
  Osage MO...Pike MO...Ralls MO...Reynolds MO...Saint Charles 
  MO...Saint Francois MO...Saint Louis City MO...Saint Louis 
  MO...Sainte Genevieve MO...Warren MO and Washington MO. 

* through late Sunday night

* Recent rainfall has set the stage for a significant flooding
  event this weekend. A slow moving and potent storm system will
  continue to interact with a very moist airmass to produce heavy
  rainfall through Sunday evening. Rainfall totals of 3 to 5
  inches are likely with locally higher amounts possible along and
  south of the Interstate 44 corridor in Missouri and Interstate
  55 corridor in Illinois.

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Moderate to major flooding is also 
  possible on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

Byrd
348 
WGUS63 KLSX 301000
FFALSX

Flood Watch
National Weather Service Saint Louis MO
500 AM CDT Sun Apr 30 2017

ILZ058>060-064-065-069-070-074-079-097>102-MOZ034>036-041-042-
047>052-059>065-072>075-084-085-099-302200-
/O.CON.KLSX.FF.A.0001.000000T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Pike IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Pittsfield, Alton, Edwardsville, Belleville, 
Cahokia, Bowling Green, Columbia, Mexico, Jefferson City, Fulton,
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
500 AM CDT Sun Apr 30 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Pike IL... 
  Randolph IL...Saint Clair IL and Washington IL. In Missouri... 
  Audrain MO...Boone MO...Callaway MO...Cole MO...Crawford MO... 
  Franklin MO...Gasconade MO...Iron MO...Jefferson MO...Lincoln 
  MO...Madison MO...Moniteau MO...Monroe MO...Montgomery MO... 
  Osage MO...Pike MO...Ralls MO...Reynolds MO...Saint Charles 
  MO...Saint Francois MO...Saint Louis City MO...Saint Louis 
  MO...Sainte Genevieve MO...Warren MO and Washington MO. 

* through late tonight

* A slow moving and potent storm system coupled with a slow moving
  front will continue to interact with a very moist airmass to
  produce additional heavy rainfall through this evening.
  Additional rainfall amounts of around one inch with locally
  higher amounts on top of the already saturated grounds and
  rivers and streams running at bankfull from the heavy rains the
  last couple of days will lead to additional flooding concerns 
  today into tonight.

* Heavy rainfall will result in flooding of low lying or poor 
  drainage areas...and ultimately dangerous flash flooding on 
  smaller creeks and streams. Moderate to major flooding is also 
  possible on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

GKS
551 
WGUS63 KLSX 302108
FFALSX

Flood Watch
National Weather Service Saint Louis MO
408 PM CDT Sun Apr 30 2017

ILZ058>060-064-065-069-070-074-079-097>102-MOZ034>036-041-042-
047>052-059>065-072>075-084-085-099-010600-
/O.CON.KLSX.FF.A.0001.000000T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Pike IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Pittsfield, Alton, Edwardsville, Belleville, 
Cahokia, Bowling Green, Columbia, Mexico, Jefferson City, Fulton,
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
408 PM CDT Sun Apr 30 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 1 AM CDT MONDAY...

The Flash Flood Watch continues for

* portions of Illinois and Missouri...including the following 
  counties...in Illinois...Bond IL...Calhoun IL...Clinton IL... 
  Fayette IL...Greene IL...Jersey IL...Macoupin IL...Madison 
  IL...Marion IL...Monroe IL...Montgomery IL...Pike IL... 
  Randolph IL...Saint Clair IL and Washington IL. In Missouri... 
  Audrain MO...Boone MO...Callaway MO...Cole MO...Crawford MO... 
  Franklin MO...Gasconade MO...Iron MO...Jefferson MO...Lincoln 
  MO...Madison MO...Moniteau MO...Monroe MO...Montgomery MO... 
  Osage MO...Pike MO...Ralls MO...Reynolds MO...Saint Charles 
  MO...Saint Francois MO...Saint Louis City MO...Saint Louis 
  MO...Sainte Genevieve MO...Warren MO and Washington MO. 

* until 1 AM CDT Monday

* Scattered thunderstorms through this evening could produce
  locally heavy rainfall. Additional rainfall amounts of around
  one inch with locally higher amounts on top of the already
  saturated grounds and ongoing flooding could produce localized
  flash flooding.

* Heavy rainfall will result in flooding of low lying or poor
  drainage areas...and dangerous flash flooding on smaller creeks
  and streams. Moderate to major flooding is either occurring or
  forecast on larger streams and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch is advanced notice that conditions are
favorable that may lead to flash flooding. People in the Watch
area, especially in flood prone areas, should use this time to
make preparations just in case. Stay informed, and be ready for
quick action if flooding is observed or if a Flash Flood Warning
is issued.

&&

$$

Glass
362 
WGUS63 KLSX 010231
FFALSX

Flood Watch
National Weather Service Saint Louis MO
931 PM CDT Sun Apr 30 2017


ILZ058>060-064-065-069-070-074-079-097>102-MOZ034>036-041-042-
047>052-059>065-072>075-084-085-099-010345-
/O.CAN.KLSX.FF.A.0001.000000T0000Z-170501T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Pike IL-Calhoun IL-Jersey IL-
Madison IL-Saint Clair IL-Monroe IL-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-
Including the cities of Litchfield, Vandalia, Centralia, Salem, 
Chester, Sparta, Pittsfield, Alton, Edwardsville, Belleville, 
Cahokia, Bowling Green, Columbia, Mexico, Jefferson City, Fulton,
Saint Charles, Washington, Union, Sullivan, Saint Louis, 
and Farmington
931 PM CDT Sun Apr 30 2017

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of Illinois and Missouri has
been cancelled. Any moderate to heavy rainfall has ended across
the area.


$$

Gosselin

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this flash flood watch went out at Apr 27, 4:08 AM CDT, 21 minutes earlier.

Area forecast discussion, Apr 27, 4:08 AM CDT, 21 minutes before
Area Forecast Discussion
National Weather Service Saint Louis MO
408 AM CDT Thu Apr 27 2017

.SHORT TERM...  (Through Late Tonight)
Issued at 407 AM CDT Thu Apr 27 2017

Showers are in the process of moving out of CWA early this morning.
This is happening as the negatively tilted upper trough lifts
northeast into the Great Lakes this morning.  GFS/NAM are showing a
shortwave ridge building into the area later today which will help
bring in some clearing temporarily.  But then the next shortwave
trough will already be advancing into the Central Plains tonight.
Showers will develop by late this evening and overnight as moisture
convergence develops on the nose of the low level jet.

There will be cold air advection this morning before it ends as the
surface ridge axis passes to the east this afternoon. Highs will be
5-15 degrees cooler today than yesterday.  There will not be much of
a diurnal change tonight with increasing clouds and winds
increasing from the south.

Britt

.LONG TERM...  (Friday through Wednesday)
Issued at 407 AM CDT Thu Apr 27 2017

Fri - Sun night

This is shaping up to be a very active prd with chances for strong
to SVR TSTMs and a prolonged prd of heavy rainfall that will likely
worsen existing flooding and cause additional flooding through the
weekend and into next week as a strong phased storm system impacts
the cntrl CONUS.

Upper level system that will eventually drive the SFC low is just
now coming onshore across the Pacific NW. Meanwhile, a short wave
rounding the base of the long wave trough will lift a weak SFC low
NE thru the FA. Both SFC and upper level systems will weaken thru
the day but will push a weak cold front thru the CWA. This bndry
will move thru the sthrn CWA drng the aftn with strong to SVR TSTMs
possible. The bndry/outflow will sink S of the FA Fri night...but
not too far. The upper level system will dig S into nthrn NM Fri/Fri
night. After midnight...the LLJ begins ramping up with elevated
precip bcmng widespread across the sthrn CWA overnight. The ECMWF is
further N than the GFS with the bndry and assoc instability so can't
rule out elevated hailers. As the upper level low emerges into the
sthrn Plains on Sat...the SFC low will lift NE out of TX. The
ongoing precip may act to suppress the northward advancement of the
warm front but this just means that wherever that sets up will
receive an extended prd of heavy rainfall. The upper level low lifts
NE into the cntrl Plains on Sun with the SFC tracking from NE TX to
NE MO by Sun evng. The warm front will be slow to move until the SFC
low moves N on Sun. Expect persistent convection along the warm
front as it moves N thru the wknd. A continuous LLJ will provide a
constant supply of theta-e rich air from the Caribbean. Dps in the
mid/upper 60s will help contribute to PWATs in excess of 1.5" with
some indications of values approaching 2.0". These values are at
least 2-3 SDs above normal. If PWATs reach above 1.75"...it would
set a record for the season. Also, warm cloud depths are between 3.5-
4 km. These values would be impressive during the summer but are on
the far high side of the spectrum for this time of the year. The
combination of the strength and dynamics of the system and the heavy
rain parameters indicate that this could be a significant hydrologic
event. Therefore, will issue a flash flood watch from Fri evng thru
Sun evng for widespread 2-5 inches with higher amounts possible
across SE MO and on into sthrn IL. The heavy rain threat will come
to an end as the SFC cold front moves thru the CWA Sun aftn/evng and
the dry slot overspreads the region. Although SPC does not have the
FA outlooked on Sun...would expect a thin line of convection to form
along the cold front with wind being the primary threat. There will
also be plenty of gradient winds assoc with this system.

Mon - Mon night

CAA will continue with wrap around precip possible across NE MO and W
cntrl IL Mon. The system becomes stacked early next week as the low
moves from the Midwest to the Grt Lks. Temps will be 10-15 degrees
below normal Mon.

Tue - Wed

A short wave embedded in NW flow will deepen as it approaches the
region producing light precip. There are still significant
differences in model solutions drng this prd...but any addtnl precip
would not help any ongoing flooding.

2%

&&

.AVIATION...  (For the 06z TAFs through 06z Thursday Night)
Issued at 1157 PM CDT Wed Apr 26 2017

Rain and IFR conditions prevail for most of the TAF sites will
begin to slowly retreat from SW to NE overnight and into early
Thursday morning, yielding VFR conditions thereafter. Dry wx is
also expected for much of the region once this current episode of
rain leaves late tonight with rain chances again on the increase
heading into Thursday night but low enough to preclude mention in
TAF. W-NW winds will continue for much of Thursday before becoming
light-variable with a surface RIDGE building in, and eventually
leading to an easterly flow later on Thursday night.

SPECIFICS FOR KSTL: IFR conditions and rain to continue until
around 09z with improvement to VFR and dry wx by daybreak
Thursday. W-NW surface winds until Thursday afternoon becoming
light-variable then easterly later on Thursday night.

TES

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Flash Flood Watch from Friday evening through late Sunday night
     for Audrain MO-Boone MO-Callaway MO-Cole MO-Crawford MO-
     Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Lincoln MO-
     Madison MO-Moniteau MO-Montgomery MO-Osage MO-Pike MO-
     Reynolds MO-Saint Charles MO-Saint Francois MO-Saint Louis
     City MO-Saint Louis MO-Sainte Genevieve MO-Warren MO-
     Washington MO.

IL...Flash Flood Watch from Friday evening through late Sunday night
     for Bond IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-
     Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-
     Montgomery IL-Randolph IL-Saint Clair IL-Washington IL.

&&

WFO LSX
Hazardous weather outlook, Apr 26, 7:00 PM CDT, 9 hours 29 minutes before
Hazardous Weather Outlook
National Weather Service Saint Louis MO
700 PM CDT Wed Apr 26 2017

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-271200-
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-
700 PM CDT Wed Apr 26 2017

This hazardous weather outlook is for portions of eastern and
central Missouri as well as west central and southwest Illinois.

.DAY ONE...Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Severe thunderstorms will be possible along and south of I-70
corridor Friday night. Large hail and damaging winds will be the
primary threats but a few tornadoes will also be possible. Heavy
rainfall is also likely through the weekend, mainly along and
south of Interstate 44 in Missouri and Interstate 70 in Illinois.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated tonight.

TES

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 26, 8:13 PM CDTRiver Flood WarningLSXReynolds55 hr
Apr 26, 9:51 PM CDTRiver Flood WarningLSXPike45 days
Apr 26, 9:51 PM CDTRiver Flood WarningLSXSaint Charles47 days

Nearby

Flash Flood Watches in Missouri, 2017Flash Flood Watches in Illinois, 2017Every flash flood watch in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.