Alert archive / Missouri / Heat Advisories in 2017

Heat Advisory 2, NWS St. Louis, MO

July 10, 201722 counties in Missouri; 16 counties in Illinois

NWS St. Louis, MO issued this heat advisory at Jul 10, 2017, 4:04 AM CDT for 22 counties in Missouri; 16 counties in Illinois. It took effect at Jul 10, 2017, 1:00 PM CDT. It was in force for 3 days.

The area

The counties it named.

The facts

Issued
Jul 10, 2017, 4:04 AM CDT (09:04 UTC)
In effect from
Jul 10, 2017, 1:00 PM CDT
Expired
Jul 13, 2017, 7:00 PM CDT
In force
3 days
Issued by
NWS St. Louis, MO
All 38 counties

Adams County, IL, Bond County, IL, Brown 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, Saint Clair County, IL, Washington County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Saint Charles County, MO, Saint Louis County, MO, Shelby County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 41 km from the middle of the area, began a volume at 09:06 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, 9.1 hours before the alert went out and 230 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 2017-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1927 joules per kilogram.LCLLFCEL10008507005003002001001 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 2017-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 square meters per square second.193958Sfc1 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
1927 J/kg
Mixed-layer CIN
-15 J/kg
Mixed-layer LCL
1553 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
178 m²/s²
Significant tornado parameter
0.4
Supercell composite
7.4

Open this sounding in Storm Lab

The text

As transmitted.

771 
WWUS73 KLSX 100904
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
404 AM CDT Mon Jul 10 2017

ILZ100>102-MOZ061-063>065-102115-
/O.NEW.KLSX.HT.Y.0002.170710T1800Z-170713T0200Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
404 AM CDT Mon Jul 10 2017

...HEAT ADVISORY IN EFFECT FROM 1 PM THIS AFTERNOON TO 9 PM CDT
WEDNESDAY...

The National Weather Service in Saint Louis has issued a Heat
Advisory, which is in effect from 1 PM this afternoon to 9 PM CDT
Wednesday.

* TIMING...heat index values will be highest during the afternoon
  and evening hours.

* HEAT INDEX VALUES...Up to 104 due to temperatures in the upper 
  90s, and dewpoints around 70.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of 
  minutes. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to the early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear light weight and loose fitting clothing when
possible and drink plenty of water.

To reduce risk during outdoor work, the Occupational Safety and
Health Administration recommends scheduling frequent rest breaks
in shaded or air conditioned environments. Anyone overcome by
heat should be moved to a cool and shaded location. Heat stroke
is an emergency, call 9-1-1 immediately.

Where's baby? Look before you lock! Young children and pets
should never be left unattended in vehicles under any
circumstances. This is especially true during warm or hot weather
when car interiors can reach lethal temperatures in a matter of
minutes.

&&

$$

42
9 follow-up statements
526 
WWUS73 KLSX 102049
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
349 PM CDT Mon Jul 10 2017


ILZ100>102-MOZ061-063>065-111000-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
349 PM CDT Mon Jul 10 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT WEDNESDAY...

* TIMING...Heat index values will be highest during the 
  afternoon and evening hours.

* HEAT INDEX VALUES...Up to 104 due to temperatures around 100, 
  and dewpoints in the upper 60s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis at
800-427-4626, or if calling from a land line phone dial 2-1-1. 
You can also call Cool Down Saint Louis at 314-241-7668.

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to the early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear light weight and loose fitting clothing when
possible and drink plenty of water.

Where's baby? Look before you lock! Young children and pets 
should never be left unattended in vehicles under any 
circumstances. This is especially true during warm or hot weather 
when car interiors can reach lethal temperatures in a matter of 
minutes.

&&

$$
Byrd
663 
WWUS73 KLSX 110836
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
336 AM CDT Tue Jul 11 2017

ILZ100>102-MOZ061-063>065-120000-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
336 AM CDT Tue Jul 11 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT WEDNESDAY...

* TIMING...Heat index values will be highest during the 
  afternoon and evening hours.

* HEAT INDEX VALUES...Up to 104 due to temperatures around 100, 
  and dewpoints in the upper 60s to lower 70s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to the early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear light weight and loose fitting clothing when
possible and drink plenty of water.

Where's baby? Look before you lock! Young children and pets
should never be left unattended in vehicles under any
circumstances. This is especially true during warm or hot weather
when car interiors can reach lethal temperatures in a matter of
minutes.

&&

$$

42
273 
WWUS73 KLSX 111751
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
1251 PM CDT Tue Jul 11 2017

ILZ095-MOZ018-019-026-027-120100-
/O.EXB.KLSX.HT.Y.0002.170711T1900Z-170712T0100Z/
Adams IL-Knox MO-Lewis MO-Marion MO-Shelby MO-
Including the cities of Hannibal and Quincy
1251 PM CDT Tue Jul 11 2017

...HEAT ADVISORY IN EFFECT UNTIL 8 PM CDT THIS EVENING...

The National Weather Service in Saint Louis has issued a Heat
Advisory, which is in effect until 8 PM CDT this evening.

* TIMING...Heat index values will be highest during the mid to
  late afternoon hours.

* HEAT INDEX VALUES...Up to 105 due to temperatures in the lower 
  90s, and dewpoints in the mid 70s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

&&

$$

ILZ100>102-MOZ061-063>065-120600-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
1251 PM CDT Tue Jul 11 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT WEDNESDAY...

* TIMING...Heat index values will be highest during the 
  afternoon and evening hours each day through Wednesday.

* HEAT INDEX VALUES...Up to 104 due to temperatures near 100, and
  dewpoints in the upper 60s to lower 70s.

* IMPACTS...The combination of hot temperatures and high humidity
  will likely lead to an increased risk of heat- related stress
  and illness. This is especially true since the heat and humidity
  is expected to persist for several days. The very young, the 
  elderly, those without air conditioning, and those participating
  in strenuous outdoor activities will be the most susceptible. 
  Also, car interiors can reach lethal temperatures in a matter of
  minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

&&

$$

Carney
199 
WWUS73 KLSX 112038
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
338 PM CDT Tue Jul 11 2017

ILZ095-MOZ018-019-026-027-121000-
/O.EXT.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Adams IL-Knox MO-Lewis MO-Marion MO-Shelby MO-
Including the cities of Hannibal and Quincy
338 PM CDT Tue Jul 11 2017

...HEAT ADVISORY NOW IN EFFECT UNTIL 9 PM CDT WEDNESDAY...

* TIMING...Heat index values will be highest during the mid to 
  late afternoon hours.

* HEAT INDEX VALUES...Up to 105 due to temperatures in the mid 
  90s, and dewpoints in the lower 70s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

&&

$$

ILZ100>102-MOZ061-063>065-121000-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
338 PM CDT Tue Jul 11 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT WEDNESDAY...

* TIMING...Heat index values will be highest during the afternoon
  and evening hours Wednesday.

* HEAT INDEX VALUES...Up to 104 due to temperatures in the upper 
  90s, and dewpoints in the upper 60s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. This is especially true since the 
  heat and humidity is expected to persist for several days. The 
  very young, the elderly, those without air conditioning, and 
  those participating in strenuous outdoor activities will be 
  the most susceptible. Also, car interiors can reach lethal 
  temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

&&

$$

Carney
589 
WWUS73 KLSX 120837
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
337 AM CDT Wed Jul 12 2017

...Heat Advisory Expanded...

.Heat Advisory Expanded.

ILZ058-059-096>099-MOZ034>036-041-042-047>052-059-060-062-122045-
/O.EXA.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Audrain MO-Boone MO-Brown IL-Calhoun IL-Callaway MO-Cole MO-
Franklin MO-Gasconade MO-Greene IL-Jersey IL-Lincoln MO-
Macoupin IL-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike IL-
Pike MO-Ralls MO-Warren MO-
Including the cities of Bowling Green, Columbia, Fulton, 
Jefferson City, Mexico, Mount Sterling, Pittsfield, Sullivan, 
Union, and Washington
337 AM CDT Wed Jul 12 2017

...HEAT ADVISORY IN EFFECT UNTIL 9 PM CDT THIS EVENING...

The National Weather Service in Saint Louis has issued a Heat
Advisory, which is in effect until 9 PM CDT this evening.

* TIMING...Heat index values will be highest during the mid to 
  late afternoon hours.

* HEAT INDEX VALUES...Up to 105 due to temperatures in the mid to upper
  90s, and dewpoints around 70.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

&&

$$

ILZ100>102-MOZ061-063>065-122045-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
337 AM CDT Wed Jul 12 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT THIS EVENING...

* TIMING...Heat index values will be highest during the mid to
  late afternoon hours Wednesday.

* HEAT INDEX VALUES...Up to 105 due to temperatures around 100, 
  and dewpoints in the mid to upper 60s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. This is especially true since the 
  heat and humidity is expected to persist for several days. The 
  very young, the elderly, those without air conditioning, and 
  those participating in strenuous outdoor activities will be 
  the most susceptible. Also, car interiors can reach lethal 
  temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

&&

$$

ILZ095-MOZ018-019-026-027-122045-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Adams IL-Knox MO-Lewis MO-Marion MO-Shelby MO-
Including the cities of Hannibal and Quincy
337 AM CDT Wed Jul 12 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT THIS EVENING...

* TIMING...Heat index values will be highest during the mid to 
  late afternoon hours.

* HEAT INDEX VALUES...Up to 105 due to temperatures in the mid
  90s, and dewpoints in the low to mid 70s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

&&

$$

KD
672 
WWUS73 KLSX 122030
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
330 PM CDT Wed Jul 12 2017

ILZ100>102-MOZ061-063>065-131000-
/O.EXT.KLSX.HT.Y.0002.000000T0000Z-170714T0000Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
330 PM CDT Wed Jul 12 2017

...HEAT ADVISORY NOW IN EFFECT UNTIL 7 PM CDT THURSDAY...

* TIMING...Heat index values will be highest during the mid to
  late afternoon hours Wednesday and Thursday.

* HEAT INDEX VALUES...Up to 108 due to temperatures around 100, 
  and dewpoints in the lower 70s.

* IMPACTS...The combination of hot temperatures and high humidity
  will continue through Thursday afternoon, leading to an
  increased risk of heat-related stress and illness. This is
  especially true since the heat and humidity has persisted since
  Sunday and is expected to continue for the fifth day in a row 
  on Thursday. The very young, the elderly, those without air 
  conditioning, and those participating in strenuous outdoor 
  activities will be the most susceptible. Also, car interiors can
  reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

&&

$$

ILZ058-059-095>099-MOZ018-019-026-027-034>036-041-042-047>052-059-
060-062-130200-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Adams IL-Audrain MO-Boone MO-Brown IL-Calhoun IL-Callaway MO-
Cole MO-Franklin MO-Gasconade MO-Greene IL-Jersey IL-Knox MO-
Lewis MO-Lincoln MO-Macoupin IL-Marion MO-Moniteau MO-Monroe MO-
Montgomery MO-Osage MO-Pike IL-Pike MO-Ralls MO-Shelby MO-
Warren MO-
Including the cities of Bowling Green, Columbia, Fulton, 
Hannibal, Jefferson City, Mexico, Mount Sterling, Pittsfield, 
Quincy, Sullivan, Union, and Washington
330 PM CDT Wed Jul 12 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT THIS EVENING...

* TIMING...Heat index values will be highest during the mid to 
  late afternoon hours.

* HEAT INDEX VALUES...Up to 105 due to temperatures in the upper 
  90s, and dewpoints in the lower 70s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will likely lead to an increased risk of heat- 
  related stress and illness. The very young, the elderly, those 
  without air conditioning, and those participating in strenuous 
  outdoor activities will be the most susceptible. Also, car 
  interiors can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

&&

$$

Carney
464 
WWUS73 KLSX 130210
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
910 PM CDT Wed Jul 12 2017


ILZ058-059-095>099-MOZ018-019-026-027-034>036-041-042-047>052-059-
060-062-130315-
/O.EXP.KLSX.HT.Y.0002.000000T0000Z-170713T0200Z/
Adams IL-Audrain MO-Boone MO-Brown IL-Calhoun IL-Callaway MO-
Cole MO-Franklin MO-Gasconade MO-Greene IL-Jersey IL-Knox MO-
Lewis MO-Lincoln MO-Macoupin IL-Marion MO-Moniteau MO-Monroe MO-
Montgomery MO-Osage MO-Pike IL-Pike MO-Ralls MO-Shelby MO-
Warren MO-
Including the cities of Bowling Green, Columbia, Fulton, 
Hannibal, Jefferson City, Mexico, Mount Sterling, Pittsfield, 
Quincy, Sullivan, Union, and Washington
910 PM CDT Wed Jul 12 2017

...HEAT ADVISORY HAS EXPIRED...

The heat advisory has been allowed to expire this evening as the 
temperatures and heat indices slowly fall.

$$

ILZ100>102-MOZ061-063>065-131415-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170714T0000Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
910 PM CDT Wed Jul 12 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THURSDAY...

* TIMING...Heat index values will be highest during the mid to
  late afternoon hours on Thursday.

* HEAT INDEX VALUES...Up to around 102 due to temperatures into
  the middle 90s, and dewpoints in the lower 70s.

* IMPACTS...The combination of hot temperatures and high 
  humidity will continue through Thursday afternoon, leading to 
  an increased risk of heat-related stress and illness. This is 
  especially true since the heat and humidity has persisted 
  since Sunday and is expected to continue for the fifth day in 
  a row on Thursday. The very young, the elderly, those without 
  air conditioning, and those participating in strenuous outdoor 
  activities will be the most susceptible. Also, car interiors 
  can reach lethal temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

&&

$$

GKS
260 
WWUS73 KLSX 130836
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
336 AM CDT Thu Jul 13 2017

...Heat Advisory Expanded...

.Heat Advisory expanded.

ILZ058>060-064-065-069-070-074-098-099-MOZ041-047>052-059-060-062-
140000-
/O.EXA.KLSX.HT.Y.0002.000000T0000Z-170714T0000Z/
Bond IL-Boone MO-Calhoun IL-Callaway MO-Clinton IL-Cole MO-
Fayette IL-Franklin MO-Gasconade MO-Greene IL-Jersey IL-
Lincoln MO-Macoupin IL-Marion IL-Moniteau MO-Montgomery IL-
Montgomery MO-Osage MO-Warren MO-Washington IL-
Including the cities of Centralia, Columbia, Fulton, 
Jefferson City, Litchfield, Salem, Sullivan, Union, Vandalia, 
and Washington
336 AM CDT Thu Jul 13 2017

...HEAT ADVISORY IN EFFECT UNTIL 7 PM CDT THIS EVENING...

The National Weather Service in Saint Louis has issued a Heat
Advisory, which is in effect until 7 PM CDT this evening.

* TIMING...Heat index values will be highest during the mid to
  late afternoon hours today.

* HEAT INDEX VALUES...Up to 105 due to temperatures in the mid to
  upper 90s and dewpoints in the low to mid 70s.

* IMPACTS...The combination of hot temperatures and high humidity
  will continue through this afternoon, leading to an increased
  risk of heat-related stress and illness. The very young, the 
  elderly, those without air conditioning, and those participating
  in strenuous outdoor activities will be the most susceptible. 
  Also, car interiors can reach lethal temperatures in a matter of
  minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment. 

&&

$$

ILZ100>102-MOZ061-063>065-140000-
/O.CON.KLSX.HT.Y.0002.000000T0000Z-170714T0000Z/
Jefferson MO-Madison IL-Monroe IL-Saint Charles MO-Saint Clair IL-
Saint Louis City MO-Saint Louis MO-
Including the cities of Alton, Belleville, Cahokia, Edwardsville,
Saint Charles, and Saint Louis
336 AM CDT Thu Jul 13 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...

* TIMING...Heat index values will be highest during the mid to
  late afternoon hours today.

* HEAT INDEX VALUES...Up to 107 due to temperatures in the mid to
  upper 90s, and dewpoints in the low to mid 70s.

* IMPACTS...The combination of hot temperatures and high humidity
  will continue through Thursday afternoon, leading to an
  increased risk of heat-related stress and illness. This is
  especially true since the heat and humidity has persisted since
  Sunday and is expected to continue for the fifth day today. The
  very young, the elderly, those without air conditioning, and 
  those participating in strenuous outdoor activities will be the 
  most susceptible. Also, car interiors can reach lethal 
  temperatures in a matter of minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures and high
humidity will occur. This combination will create a situation in
which heat-related illnesses are possible, especially for those
living in un-air conditioned homes or apartments. People in the
Advisory area are advised to avoid poorly ventilated areas and
prolonged work in the sun. Also, keep plenty of liquids on hand
and try to stay in an air conditioned environment.

People in the Saint Louis Metropolitan Area can get information
about cooling centers or energy assistance related to the
excessive heat by calling the United Way of Greater Saint Louis
at 800-427-4626, or if calling from a land line phone dial 2-1-1.
You can also call Cool Down Saint Louis at 314-241-7668.

&&

$$

KD
487 
WWUS73 KLSX 140005
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
705 PM CDT Thu Jul 13 2017

ILZ058>060-064-065-069-070-074-098>102-MOZ041-047>052-059>065-
140115-
/O.EXP.KLSX.HT.Y.0002.000000T0000Z-170714T0000Z/
Bond IL-Boone MO-Calhoun IL-Callaway MO-Clinton IL-Cole MO-
Fayette IL-Franklin MO-Gasconade MO-Greene IL-Jefferson MO-
Jersey IL-Lincoln MO-Macoupin IL-Madison IL-Marion IL-Moniteau MO-
Monroe IL-Montgomery IL-Montgomery MO-Osage MO-Saint Charles MO-
Saint Clair IL-Saint Louis City MO-Saint Louis MO-Warren MO-
Washington IL-
Including the cities of Alton, Belleville, Cahokia, Centralia, 
Columbia, Edwardsville, Fulton, Jefferson City, Litchfield, 
Saint Charles, Saint Louis, Salem, Sullivan, Union, Vandalia, 
and Washington
705 PM CDT Thu Jul 13 2017

...HEAT ADVISORY HAS EXPIRED...

The heat advisory has been allowed to expire this evening as the 
temperatures and heat index values continue to fall and much
cooler temperatures expected tomorrow. 

$$

Tilly

What forecasters said that day

The local office's own words before this heat advisory 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 heat advisory went out at Jul 10, 3:59 AM CDT, 5 minutes earlier.

Area forecast discussion, Jul 10, 3:59 AM CDT, 5 minutes before
Area Forecast Discussion
National Weather Service Saint Louis MO
359 AM CDT Mon Jul 10 2017

.SHORT TERM...  (Through Late Tonight)
Issued at 307 AM CDT Mon Jul 10 2017

The synoptic pattern early this morning features northwesterly
upper-level flow over the region due to a ridge over the
Intermountain West and a downstream trough located over the Great
Lakes region. This regime will deamplify through the period but
west-northwesterly flow will still persist through tonight.

We continue to monitor an MCS located over eastern IA and just
now getting into northern IL. The latest trends continue to
suggest this system will likely miss the region just to the
northeast. However, with the veering low-level jet, still think
the potential is there to get some development on the western side
of the cold pool as the entire system sags southeast, so have
maintained a very small area of slight chance pops over west-
central IL.

Otherwise, think much of the region will remain dry through the
mid- afternoon hours with an overall lack of forcing and a mid-
level cap building into the region. While there may be some
mid/high cloud cover this morning, skies should clear out by this
afternoon. Slightly higher 1000-850mb thicknesses and 850mb temps
suggest today will likely be a degree or two warmer than
yesterday. Given Sunday's hot temperatures in the STL metro area
and the continued heat expected today into this week, we will be
hoisting a Heat Advisory for the STL Metro (see long term section
below for more details). Heat indices areawide are expected to
reach from 95-104, with the highest values over east-central and
northeast MO.

By late this afternoon into early this evening, attention will
turn to the north as a synoptic cold front (currently still over
northwest IA) sags southeast toward the IA/MO border. Convergence
along this boundary should be enough to spark convection late this
afternoon and especially this evening near the IA/MO border. This
convection will slowly sag southeast through the evening and
early overnight hours, being maintained by moisture convergence
into the boundary along the nose of a 925mb 30kt low-level jet.
While synoptic forcing will be fairly weak and not overly
supportive of forward-propagating MCSs in our area, the strongly
unstable airmass near the front could lead to some strong to
locally severe storms capable of locally damaging winds and large
hail.

KD

.LONG TERM...  (Tuesday through Sunday)
Issued at 307 AM CDT Mon Jul 10 2017

The primary forecast problem in the extended period is a stretch
of hot/humid conditions for most of the week along with periodic
thunderstorm chances.

This is the first prolonged stretch of oppressively hot/humid
conditions so far this summer, and it takes time for the human
body to acclimate to such conditions. Please do not interpret the
absence of a Heat Advisory in a given location to mean that it
won't be hot/humid there-- it will be hot/humid almost everywhere.

WFO LSX issues Heat Advisories on a county-by-county basis based
on either the duration of the hot/humid weather (4-day stretch
with widespread heat index values of 100-104 deg F) or the
intensity of the hot/humid weather (a single day with widespread
max heat index values of 105-109 deg F).

Heat index values reached 100 deg F in the St. Louis metro area
yesterday, and they are expected to be at least that high on each
day from Monday through Wednesday. At this point, we are
reasonably confident that there will be a 4-day stretch of
hot/humid conditions in the St. Louis metro area (Sun - Wed),
therefore a Heat Advisory has been issued based on duration
criteria.

Separately, the heat index may approach 105 deg F across parts of
central and northeast Missouri as well as parts of west central
and southwest Illinois, particularly on Tuesday and Wednesday. A
new Heat Advisory may eventually be needed for these areas for a
single day (possibly two) based on intensity criteria.

Finally, slightly cooler temperatures are expected on Thursday
due to cloud cover and precipitation near a cold front. However,
there is some question about how far south the front and its
associated precipitation and cloud cover will extend. If the front
does not progress as far south as expected, there could be an
extra day of hot/humid weather across most of the area. In that
case, most of the area may experience HI values of 100+ deg F for
4 days in a row (Mon - Thu), and a Heat Advisory might be needed
across a larger geographical area based on duration criteria.
Confidence in this scenario is too low at this time to issue a
larger Heat Advisory.

Thunderstorm chances will be tied to a stalled frontal boundary
which initially stretches across the IA/MN border on Tue morning
before lifting northward as a warm front on Tue night. By Wed
night, the parent surface low will have shifted eastward and the
flow aloft will have become increasingly northwesterly, which
should allow the boundary to drop southward as a cold front. There
is some model disagreement about how far south the front will
progress, and there is also a concern that outflow from MCS
activity may push the effective boundary farther south than
previously anticipated. LLJ interaction with the stalled boundary
or effective front will support periods of SHRA/TSRA during the
middle and end of the week. After a ridge axis amplifies over the
western CONUS towards the end of the week, the resulting
northwest flow aloft over MO/IL will be conducive for weak upper
disturbances to move across the area and support periods of
SHRA/TSRA. SChc-Chc PoPs appear reasonable given that these
features are notoriously difficult to forecast accurately this far
in advance.

Kanofsky

&&

.AVIATION...  (For the 06z TAFs through 06z Monday Night)
Issued at 1106 PM CDT Sun Jul 9 2017

Nocturnal convection late tonight into Monday morning should be
northeast of the taf sites, although showers/storms may pass close
to UIN. There will mainly be some high level convective debris
cloudiness advecting into the area. A cold front will sag
southward into extreme northern MO Monday afternoon and night with
scattered convection possible near this front Monday afternoon
and Monday night. For now will leave the UIN taf dry. There will
be some LLWS late tonight in UIN and COU, but it does not appear
to be strong enough to include in the respective tafs. There
should be scattered diurnal cumulus clouds late Monday morning and
afternoon. Southwest surface winds will continue through the
period, gusty late Monday morning and afternoon.

SPECIFICS FOR KSTL: Nocturnal convection late tonight into Monday
morning should be well northeast of the STL area. There will
mainly be some high level convective debris cloudiness advecting
into the area. A cold front will sag southward into extreme
northern MO Monday afternoon and night with scattered convection
possible near this front Monday afternoon and Monday night. For
now will leave the STL taf dry, although convection may get close
to STL Monday night. There should be scattered diurnal cumulus
clouds late Monday morning and afternoon. Southwest surface winds
will continue through the period, gusty late Monday morning and
afternoon.

GKS

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Heat Advisory from 2 PM this afternoon to 9 PM CDT Wednesday for
     Jefferson MO-Saint Charles MO-Saint Louis City MO-Saint
     Louis MO.

IL...Heat Advisory from 2 PM this afternoon to 9 PM CDT Wednesday for
     Madison IL-Monroe IL-Saint Clair IL.

&&

WFO LSX
Hazardous weather outlook, Jul 9, 3:37 PM CDT, 12 hours 27 minutes before
Hazardous Weather Outlook
National Weather Service Saint Louis MO
337 PM CDT Sun Jul 9 2017

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-101200-
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-
337 PM CDT Sun Jul 9 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...Monday through Saturday

Isolated strong to severe thunderstorms will be possible mainly
Monday evening and overnight over northeast Missouri and west
central Illinois. The main threats would be localized large hail
and locally damaging winds.

Heat index values of 100 to 105 are expected Monday through
Wednesday across much of the area.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated tonight.

Tilly

Nearby

Heat Advisories in Missouri, 2017Heat Advisories in Illinois, 2017Every heat advisory 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.