Alert archive / Illinois / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 49, NWS St. Louis, MO

July 29, 1986Brown County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 29, 1986, 1:20 AM CDT for Brown County, Illinois. It was in force for 40 min.

The area

The counties it named.

The facts

Issued
Jul 29, 1986, 1:20 AM CDT (06:20 UTC)
Expired
Jul 29, 1986, 2:00 AM CDT
In force
40 min
Issued by
NWS St. Louis, MO
Area
Whole counties

County Brown County, IL

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Peoria Regional, IL (KPIA), launched 00:00Z, 6.3 hours before the alert went out and 125 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, Peoria Regional, IL at 00:00Z on 1986-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2172 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, Peoria Regional, IL at 00:00Z on 1986-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 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
2172 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
1200 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.6

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 12:30 AM CDTSevere Thunderstorm WarningLSXAdams45 min
Jul 29, 12:55 AM CDTSevere Thunderstorm WarningLSXAdams45 min
Jul 29, 1:20 AM CDTSevere Thunderstorm WarningLSXPike40 min
Jul 29, 1:45 AM CDTSevere Thunderstorm WarningLSXScott45 min
Jul 29, 2:10 AM CDTSevere Thunderstorm WarningLSXCalhoun, Greene50 min
Jul 29, 2:40 AM CDTSevere Thunderstorm WarningLSXJersey50 min
Jul 29, 3:10 AM CDTSevere Thunderstorm WarningLSXMadison50 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1986Every severe thunderstorm warning in 1986

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.