Alert archive / Illinois / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 13, NWS St. Louis, MO

May 21, 1987Brown County, Pike County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 21, 1987, 8:10 PM CDT for Brown County, Pike County, Illinois. It was in force for 50 min. 2 reports 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
May 21, 1987, 8:10 PM CDT (01:10 UTC)
Expired
May 21, 1987, 9:00 PM CDT
In force
50 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Brown County, IL, Pike County, IL

The radar

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

What was reported inside it

TimeReportWhereRemark
May 21, 8:35 PM CDTHail 1.75Pike, IL
May 21, 8:40 PM CDTThunderstorm Wind 0Brown, IL

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Peoria Regional, IL (KPIA), launched 00:00Z, 1.2 hours before the alert went out and 142 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 1987-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2351 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 1987-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 55 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
2351 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
1819 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
55 m²/s²
0-3 km storm-relative helicity
98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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
May 21, 7:01 PM CDTSevere Thunderstorm WarningLSXMonroe, Randolph, Saint Clair59 min
May 21, 7:12 PM CDTSevere Thunderstorm WarningLSXAdams, Brown48 min
May 21, 7:25 PM CDTSevere Thunderstorm WarningLSXGreene, Pike, Scott50 min
May 21, 7:25 PM CDTSevere Thunderstorm WarningLSXCalhoun50 min
May 21, 8:10 PM CDTSevere Thunderstorm WarningLSXScott50 min
May 21, 8:57 PM CDTSevere Thunderstorm WarningLSXGreene, Scott53 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1987Every severe thunderstorm warning in 1987

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.