Alert archive / Ohio / Heat Advisories in 2021

Heat Advisory 3, NWS Cleveland, OH

August 12, 202125 counties in Ohio

NWS Cleveland, OH issued this heat advisory at Aug 12, 2021, 4:14 AM EDT for 25 counties in Ohio. It took effect at Aug 12, 2021, 12:00 PM EDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Aug 12, 2021, 4:14 AM EDT (08:14 UTC)
In effect from
Aug 12, 2021, 12:00 PM EDT
Expired
Aug 12, 2021, 7:20 PM EDT
In force
7 hr
Issued by
NWS Cleveland, OH
All 25 counties

Ashland County, OH, Crawford County, OH, Cuyahoga County, OH, Erie County, OH, Hancock County, OH, Holmes County, OH, Huron County, OH, Knox County, OH, Lorain County, OH, Lucas County, OH, Mahoning County, OH, Marion County, OH, Medina County, OH, Morrow County, OH, Ottawa County, OH, Portage County, OH, Richland County, OH, Sandusky County, OH, Seneca County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Wayne County, OH, Wood County, OH, Wyandot County, OH

The radar

The Cleveland radar (KCLE), 60 km from the middle of the area, began a volume at 08:17 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

Detroit, MI (KDTX), launched 00:00Z, 8.2 hours before the alert went out and 204 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, Detroit, MI at 00:00Z on 2021-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 00:00Z on 2021-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 243 square meters per square second.19395878Sfc1 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
12 J/kg
Mixed-layer CIN
-458 J/kg
Mixed-layer LCL
1474 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
243 m²/s²
0-3 km storm-relative helicity
373 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

177 
WWUS71 KCLE 120814
NPWCLE

URGENT - WEATHER MESSAGE
National Weather Service Cleveland OH
414 AM EDT Thu Aug 12 2021

OHZ003-006>011-017>023-027>033-036>038-047-121615-
/O.NEW.KCLE.HT.Y.0003.210812T1600Z-210813T0000Z/
Lucas-Wood-Ottawa-Sandusky-Erie-Lorain-Cuyahoga-Hancock-Seneca-
Huron-Medina-Summit-Portage-Trumbull-Wyandot-Crawford-Richland-
Ashland-Wayne-Stark-Mahoning-Marion-Morrow-Holmes-Knox-
Including the cities of Toledo, Bowling Green, Perrysburg, 
Port Clinton, Oak Harbor, Genoa, Fremont, Bellevue, Clyde, 
Sandusky, Huron, Lorain, Elyria, North Ridgeville, Avon Lake, 
Cleveland, Findlay, Tiffin, Fostoria, Norwalk, Willard, 
Brunswick, Medina, Wadsworth, Akron, Kent, Aurora, Streetsboro, 
Ravenna, Warren, Niles, Upper Sandusky, Carey, Bucyrus, Galion, 
Crestline, Mansfield, Ashland, Wooster, Orrville, Rittman, 
Canton, Massillon, Alliance, Youngstown, Boardman, Austintown, 
Marion, Mount Gilead, Cardington, Millersburg, Killbuck, 
and Mount Vernon
414 AM EDT Thu Aug 12 2021

...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS
EVENING...

* WHAT...Heat index values up to 100 expected.

* WHERE...Portions of north central, northeast and northwest 
  Ohio.

* WHEN...From noon today to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

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

&&

$$

For more information from the National Weather Service visit
http://www.weather.gov/cle
3 follow-up statements
275 
WWUS71 KCLE 121413
NPWCLE

URGENT - WEATHER MESSAGE
National Weather Service Cleveland OH
1013 AM EDT Thu Aug 12 2021

OHZ003-006>011-017>023-027>033-036>038-047-122215-
/O.CON.KCLE.HT.Y.0003.210812T1600Z-210813T0000Z/
Lucas-Wood-Ottawa-Sandusky-Erie-Lorain-Cuyahoga-Hancock-Seneca-
Huron-Medina-Summit-Portage-Trumbull-Wyandot-Crawford-Richland-
Ashland-Wayne-Stark-Mahoning-Marion-Morrow-Holmes-Knox-
Including the cities of Toledo, Bowling Green, Perrysburg, 
Port Clinton, Oak Harbor, Genoa, Fremont, Bellevue, Clyde, 
Sandusky, Huron, Lorain, Elyria, North Ridgeville, Avon Lake, 
Cleveland, Findlay, Tiffin, Fostoria, Norwalk, Willard, 
Brunswick, Medina, Wadsworth, Akron, Kent, Aurora, Streetsboro, 
Ravenna, Warren, Niles, Upper Sandusky, Carey, Bucyrus, Galion, 
Crestline, Mansfield, Ashland, Wooster, Orrville, Rittman, 
Canton, Massillon, Alliance, Youngstown, Boardman, Austintown, 
Marion, Mount Gilead, Cardington, Millersburg, Killbuck, 
and Mount Vernon
1013 AM EDT Thu Aug 12 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 100 degrees expected if 
  sufficient daytime heating occurs. The best potential for these 
  high heat indices appears to exist in Lucas, Wood, and Hancock 
  Counties.

* WHERE...Portions of north central, northeast and northwest 
  Ohio.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

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

&&

$$

For more information from the National Weather Service visit
http://www.weather.gov/cle
170 
WWUS71 KCLE 121612
NPWCLE

URGENT - WEATHER MESSAGE
National Weather Service Cleveland OH
1212 PM EDT Thu Aug 12 2021

OHZ022-023-033-121715-
/O.CAN.KCLE.HT.Y.0003.000000T0000Z-210813T0000Z/
Portage-Trumbull-Mahoning-
Including the cities of Kent, Aurora, Streetsboro, Ravenna, 
Warren, Niles, Youngstown, Boardman, and Austintown
1212 PM EDT Thu Aug 12 2021

...HEAT ADVISORY IS CANCELLED...

While it will be a very warm and humid afternoon, heat indices of
100F or slightly hotter are no longer expected.

$$

OHZ003-006>011-017>021-027>032-036>038-047-130000-
/O.CON.KCLE.HT.Y.0003.000000T0000Z-210813T0000Z/
Lucas-Wood-Ottawa-Sandusky-Erie-Lorain-Cuyahoga-Hancock-Seneca-
Huron-Medina-Summit-Wyandot-Crawford-Richland-Ashland-Wayne-Stark-
Marion-Morrow-Holmes-Knox-
Including the cities of Toledo, Bowling Green, Perrysburg, 
Port Clinton, Oak Harbor, Genoa, Fremont, Bellevue, Clyde, 
Sandusky, Huron, Lorain, Elyria, North Ridgeville, Avon Lake, 
Cleveland, Findlay, Tiffin, Fostoria, Norwalk, Willard, 
Brunswick, Medina, Wadsworth, Akron, Upper Sandusky, Carey, 
Bucyrus, Galion, Crestline, Mansfield, Ashland, Wooster, 
Orrville, Rittman, Canton, Massillon, Alliance, Marion, 
Mount Gilead, Cardington, Millersburg, Killbuck, and Mount Vernon
1212 PM EDT Thu Aug 12 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 101 degrees.

* WHERE...Portions of north central, northeast and northwest 
  Ohio.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

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

&&

$$

For more information from the National Weather Service visit
http://www.weather.gov/cle
325 
WWUS71 KCLE 122320
NPWCLE

URGENT - WEATHER MESSAGE
National Weather Service Cleveland OH
720 PM EDT Thu Aug 12 2021

OHZ003-006>011-017>021-027>032-036>038-047-130030-
/O.CAN.KCLE.HT.Y.0003.000000T0000Z-210813T0000Z/
Lucas-Wood-Ottawa-Sandusky-Erie-Lorain-Cuyahoga-Hancock-Seneca-
Huron-Medina-Summit-Wyandot-Crawford-Richland-Ashland-Wayne-Stark-
Marion-Morrow-Holmes-Knox-
Including the cities of Toledo, Bowling Green, Perrysburg, 
Port Clinton, Oak Harbor, Genoa, Fremont, Bellevue, Clyde, 
Sandusky, Huron, Lorain, Elyria, North Ridgeville, Avon Lake, 
Cleveland, Findlay, Tiffin, Fostoria, Norwalk, Willard, 
Brunswick, Medina, Wadsworth, Akron, Upper Sandusky, Carey, 
Bucyrus, Galion, Crestline, Mansfield, Ashland, Wooster, 
Orrville, Rittman, Canton, Massillon, Alliance, Marion, 
Mount Gilead, Cardington, Millersburg, Killbuck, and Mount Vernon
720 PM EDT Thu Aug 12 2021

...HEAT ADVISORY IS CANCELLED...

The Heat Advisory has been cancelled early this evening.

$$

For more information from the National Weather Service visit
http://www.weather.gov/cle

The office that day

Everything else NWS Cleveland, OH issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 12, 4:56 AM EDTSpecial Marine WarningCLE64 min
Aug 12, 5:12 AM EDTSpecial Marine WarningCLE33 min
Aug 12, 7:33 AM EDTSpecial Marine WarningCLE87 min
Aug 12, 8:21 AM EDTSpecial Weather StatementCLEMedina39 min
Aug 12, 8:59 AM EDTSpecial Marine WarningCLE71 min
Aug 12, 9:03 AM EDTSpecial Weather StatementCLEAshtabula, Lake42 min
Aug 12, 10:15 AM EDTSpecial Weather StatementCLECuyahoga, Geauga, Portage45 min
Aug 12, 10:23 AM EDTAreal Flood AdvisoryCLECuyahoga2 hr
Aug 12, 10:28 AM EDTSevere Thunderstorm WarningCLEAshtabula, Cuyahoga, Geauga, Portage, Summit, Trumbull47 min
Aug 12, 11:01 AM EDTSevere Thunderstorm Warning Considerable damage threatCLEAshtabula, Trumbull40 min
Aug 12, 3:29 PM EDTSpecial Weather StatementCLEPortage, Trumbull46 min
Aug 12, 3:37 PM EDTSpecial Weather StatementCLEGeauga53 min
Aug 12, 3:42 PM EDTSevere Thunderstorm WarningCLEGeauga, Portage, Summit48 min
Aug 12, 3:54 PM EDTSpecial Weather StatementCLEMahoning51 min
Aug 12, 4:00 PM EDTSpecial Weather StatementCLESummit45 min
Aug 12, 4:09 PM EDTSevere Thunderstorm WarningCLEPortage, Summit51 min
Aug 12, 4:27 PM EDTSevere Thunderstorm WarningCLEGeauga, Portage, Summit, Trumbull63 min
Aug 12, 4:52 PM EDTSevere Thunderstorm WarningCLEMahoning, Portage68 min
Aug 12, 6:11 PM EDTSpecial Weather StatementCLEMorrow, Richland64 min

Nearby

Heat Advisories in Ohio, 2021Every heat advisory in 2021

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.