Alert archive / Arizona / Excessive Heat Warnings in 2021

Excessive Heat Warning 3, NWS Tucson, AZ

August 24, 20216 counties in Arizona

NWS Tucson, AZ issued this excessive heat warning at Aug 24, 2021, 2:23 PM MST for 6 counties in Arizona. It took effect at Aug 25, 2021, 10:00 AM MST. It was in force for 58 hr. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 24, 2021, 2:23 PM MST (21:23 UTC)
In effect from
Aug 25, 2021, 10:00 AM MST
Expired
Aug 27, 2021, 8:00 PM MST
In force
58 hr
Issued by
NWS Tucson, AZ

Counties Cochise County, AZ, Graham County, AZ, Greenlee County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 61 km from the middle of the area, began a volume at 21:24 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.

What was reported inside it

TimeReportWhereRemark
Aug 27, 4:36 PM MSTTSTM WND GST 624 Ene Safford, AZASOS STATION KSAD SAFFORD REGIONAL AIRPORT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 12:00Z, 9.4 hours before the alert went out and 49 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, Tuscon, AZ at 12:00Z on 2021-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 97 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, Tuscon, AZ at 12:00Z on 2021-08-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 square meters per square second.1939Sfc1 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
97 J/kg
Mixed-layer CIN
-266 J/kg
Mixed-layer LCL
1989 m above ground
0-6 km bulk shear
3 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
-2 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

215 
WWUS75 KTWC 242123
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
223 PM MST Tue Aug 24 2021

AZZ501-502-504-505-250530-
/O.UPG.KTWC.EH.A.0003.210825T1700Z-210828T0300Z/
/O.NEW.KTWC.EH.W.0003.210825T1700Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, and Picacho Peak State Park
223 PM MST Tue Aug 24 2021

...EXCESSIVE HEAT WARNING IN EFFECT FROM 10 AM WEDNESDAY TO 8 PM
MST FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 
  to 112 degrees. 

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson Metro
  Area, and South Central Pinal County.

* WHEN...From 10 AM Wednesday to 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly increase
  the potential for heat related illnesses, particularly for those
  working or participating in outdoor activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

AZZ506-507-509-250530-
/O.NEW.KTWC.EH.W.0003.210825T1700Z-210828T0300Z/
Southeast Pinal County-Upper San Pedro River Valley-
Upper Gila River Valley-
Including the cities of Mammoth, Oracle, and Safford
223 PM MST Tue Aug 24 2021

...EXCESSIVE HEAT WARNING IN EFFECT FROM 10 AM WEDNESDAY TO 8 PM
MST FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 to
  111 degrees.

* WHERE...Southeast Pinal County, Upper San Pedro River Valley 
  and Upper Gila River Valley.

* WHEN...From 10 AM Wednesday to 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly increase
  the potential for heat related illnesses, particularly for those
  working or participating in outdoor activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

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8 follow-up statements
392 
WWUS75 KTWC 250446
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
946 PM MST Tue Aug 24 2021

AZZ501-502-504>507-509-251300-
/O.CON.KTWC.EH.W.0003.210825T1700Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
946 PM MST Tue Aug 24 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT FROM 10 AM WEDNESDAY
TO 8 PM MST FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 
  to 112 degrees.

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, and South Central Pinal County.

* WHEN...From 10 AM Wednesday to 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Meyer

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
854 
WWUS75 KTWC 250923
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
223 AM MST Wed Aug 25 2021

AZZ501-502-504>507-509-252000-
/O.CON.KTWC.EH.W.0003.210825T1700Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
223 AM MST Wed Aug 25 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT FROM 10 AM THIS
MORNING TO 8 PM MST FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 
  to 112 degrees.

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, and South Central Pinal County.

* WHEN...From 10 AM Wednesday to 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
565 
WWUS75 KTWC 252133
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
233 PM MST Wed Aug 25 2021

AZZ501-502-504>507-509-260545-
/O.CON.KTWC.EH.W.0003.000000T0000Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
233 PM MST Wed Aug 25 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST
FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 
  to 112 degrees.

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, South Central Pinal County, Southeast Pinal 
  County, Upper San Pedro River Valley and Upper Gila River 
  Valley.

* WHEN...Until 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
647 
WWUS75 KTWC 260446
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
946 PM MST Wed Aug 25 2021

AZZ501-502-504>507-509-261300-
/O.CON.KTWC.EH.W.0003.000000T0000Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
946 PM MST Wed Aug 25 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST
FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 
  to 112 degrees.

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, South Central Pinal County, Southeast Pinal 
  County, Upper San Pedro River Valley and Upper Gila River 
  Valley.

* WHEN...Until 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
288 
WWUS75 KTWC 260939
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
239 AM MST Thu Aug 26 2021

AZZ501-502-504>507-509-262000-
/O.CON.KTWC.EH.W.0003.000000T0000Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
239 AM MST Thu Aug 26 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST
FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 105 
  to 112 degrees.

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, South Central Pinal County, Southeast Pinal 
  County, Upper San Pedro River Valley and Upper Gila River 
  Valley.

* WHEN...Until 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
322 
WWUS75 KTWC 262153
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
253 PM MST Thu Aug 26 2021

AZZ501-502-504>507-509-271700-
/O.CON.KTWC.EH.W.0003.000000T0000Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
253 PM MST Thu Aug 26 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST
FRIDAY...

* WHAT...Dangerously hot conditions. Afternoon temperatures 102 to
  110 degrees. Hottest temperatures in the lower deserts west of
  Tucson. 

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, South Central Pinal County, Southeast Pinal 
  County, Upper San Pedro River Valley and Upper Gila River 
  Valley.

* WHEN...Until 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
076 
WWUS75 KTWC 271659
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
959 AM MST Fri Aug 27 2021

AZZ501-502-504>507-509-280300-
/O.CON.KTWC.EH.W.0003.000000T0000Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
959 AM MST Fri Aug 27 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST THIS
EVENING...

* WHAT...Dangerously hot conditions. Afternoon temperatures 102 
  to 110 degrees. Hottest temperatures in the lower deserts west 
  of Tucson.

* WHERE...Western Pima County, Tohono O'odham Nation, Tucson 
  Metro Area, South Central Pinal County, Southeast Pinal 
  County, Upper San Pedro River Valley and Upper Gila River 
  Valley.

* WHEN...Until 8 PM MST Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Keep in mind you may need to adjust your plans based on the
latest health and safety guidelines from CDC and your local
officials. Cooling shelters may need to take your temperature or
ask questions about how you are feeling.

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.

&&

$$

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
427 
WWUS75 KTWC 280254
NPWTWC

URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
754 PM MST Fri Aug 27 2021

AZZ501-502-504>507-509-280400-
/O.EXP.KTWC.EH.W.0003.000000T0000Z-210828T0300Z/
Western Pima County-Tohono O'odham Nation-Tucson Metro Area-
South Central Pinal County-Southeast Pinal County-
Upper San Pedro River Valley-Upper Gila River Valley-
Including the cities of Ajo, Organ Pipe Cactus N.M., Sells, 
Tucson, Green Valley, Marana, Vail, Picacho Peak State Park, 
Mammoth, Oracle, and Safford
754 PM MST Fri Aug 27 2021

...EXCESSIVE HEAT WARNING WILL EXPIRE AT 8 PM MST THIS EVENING...

Temperatures will continue to lower through the rest of this
evening. Therefore, the warning will be allowed to expire at 8 pm
MST.

$$

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The office that day

Everything else NWS Tucson, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 23, 5:09 PM MSTSpecial Weather StatementTWCGraham51 min

Nearby

Excessive Heat Warnings in Arizona, 2021Every excessive heat warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.