Alert archive / Illinois / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 18, NWS Chicago, IL
NWS Chicago, IL issued this severe thunderstorm warning at Jun 14, 2002, 11:31 AM CDT for Cook County, Illinois. It was in force for 29 min. 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
- Jun 14, 2002, 11:31 AM CDT (16:31 UTC)
- Expired
- Jun 14, 2002, 12:00 PM CDT
- In force
- 29 min
- Issued by
- NWS Chicago, IL
- Area
- Counties, with a storm outline in the text
County Cook County, IL
The radar
The Chicago radar (KLOT), 49 km from the middle of the area, began a volume at 16:33 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jun 14, 11:43 AM CDT | Hail 0.75 | Alsip, 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.
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 4.5 hours before the alert went out and 210 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.
- Mixed-layer CAPE
- 1 J/kg
- Mixed-layer CIN
- -82 J/kg
- Mixed-layer LCL
- 1434 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- -20 m²/s²
- 0-3 km storm-relative helicity
- 34 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Chicago, IL wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 14, 2:23 AM CDT, 9 hours 8 minutes earlier.
Area forecast discussion, Jun 14, 2:23 AM CDT, 9 hours 8 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO IL 223 AM CDT FRI JUN 14 2002 FORECAST CONCERN FOCUSES ON UPPER LOW OVER NORTHERN PLAINS AND ITS SLOW MOVEMENT ACROSS LAKES REGION THRU EARLY NEXT WEEK. ONE VORT MOVING THRU REGION THIS AM WITH A FEW SHOWERS FINALLY DISSIPATING. UPPER LOW SLOWLY MOVES FROM MINNESOTA THIS AM TO SOUTHERN LAKES TODAY THEN PUSHING TO EASTERN LAKES BY SUNDAY MORNING...WHERE IT BECOMES STATIONARY. SERIES OF VORTS ROTATE AROUND UPPER LOW EACH DAY BRINGING THREAT OF SHOWERS AND A FEW THUNDERSTORMS. DAYTIME HEATING AND TIMING OF VORTS PUT BEST CHANCES OF PRECIP AFTERNOON AND EVENING. WILL EXTEND CHANCE OF PRECIP INTO SUNDAY...WITH UPPER LOW FINALLY LIFTING NORTHEAST INTO QUEBEC ON MONDAY AND SURFACE HIGH BUILDING IN ACROSS CENTRAL PLAINS AND OHIO VALLEY...WILL DRY THINGS OUT MON AND TUES. WARM ADVECTION BEHIND LOW MIDWEEK AND WILL BRING MENTION OF PRECIP BACK WED AND THURS. ANOTHER CONCERN IS THREAT OF HAIL/WINDS TODAY. FREEZING LEVEL ONLY AT 8 KFT AND WINDS AT 500MB 40KTS OR SO. CAPE RUNNING 300-600 J/KG. SO SOME THUNDERSTORMS CERTAINLY CAPABLE OF SMALL HAIL AND GUSTY WINDS BUT WOULD EXPECT MOST ACTIVITY TO REMAIN BELOW SVR LIMITS. AS FOR TEMPS GUIDANCE SIMILAR INTO THE WEEKEND WITH THE EXCEPTION OF THE MAV MUCH WARMER ON SAT. WITH PRECIP MENTIONED WILL GO WITH COOLER FWC SAT...OTHERWISE WILL STAY CLOSE. AS SURFACE HIGH MOVES EAST TUES...TEMPS WARM INTO THE 80S BY LATE WEEK. .CHI...NONE. CMS
In the hours before
Special weather statement, Jun 14, 5:32 AM CDT, 5 hours 59 minutes before
ILZ003>006-008-010>014-019>023-032>033-039-INZ001>002-010>011- 019-141700- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHICAGO IL 600 AM CDT/EST FRI JUN 14 2002 FOR NORTH CENTRAL AND NORTHEAST ILLINOIS AND NORTHWEST INDIANA... NO SEVERE WEATHER IS EXPECTED TODAY OR TONIGHT. AN UPPER LEVEL LOW PRESSURE OVER THE MIDWEST THIS MORNING...WILL SLOWLY MOVE EAST INTO THE GREAT LAKES REGION TODAY. UPPER LEVEL DISTURBANCES WILL ROTATE AROUND THIS UPPER LOW THROUGH SUNDAY. ALONG WITH DAYTIME HEATING...SHOWERS AND A FEW THUNDERSTORMS WILL BE POSSIBLE DURING THE AFTERNOON AND EVENING HOURS...TODAY...SATURDAY AND SUNDAY. ALTHOUGH NO SEVERE WEATHER IS EXPECTED TODAY...SATURDAY OR SUNDAY... SOME THUNDERSTORMS THIS AFTERNOON MAY PRODUCE SMALL HAIL...BRIEF HEAVY RAIN...AND GUSTY WINDS...AS THE COLDEST AIR ALOFT ASSOCIATED WITH THIS UPPER LEVEL LOW...MOVES THROUGH THE REGION TODAY.
The office that day
Everything else NWS Chicago, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 14, 11:58 AM CDT | Severe Thunderstorm Warning | LOT | Cook | 47 min |
Nearby
Severe Thunderstorm Warnings in Illinois, 2002Every severe thunderstorm warning in 2002
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; radar from the NEXRAD Level II archive.