Alert archive / Illinois / Tornado Watches in 2007
Tornado Watch 719
The Storm Prediction Center issued this tornado watch at Oct 18, 2007, 2:01 AM CDT for 35 counties in Illinois. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 18, 2007, 2:01 AM CDT (07:01 UTC)
- Expired
- Oct 18, 2007, 7:22 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
All 35 counties
Cass County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Fulton County, IL, Jasper County, IL, Knox County, IL, Lawrence County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Richland County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Woodford County, IL
The radar
The Lincoln radar (KILX), 17 km from the middle of the area, began a volume at 07:02 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 30%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 5%
- Ten or more severe hail reports
- 10%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 18, 2:01 AM CDT | Severe Thunderstorm Warning | ILX | Morgan, Sangamon | 44 min |
| Oct 18, 3:58 AM CDT | Severe Thunderstorm Warning | ILX | Clay, Effingham, Jasper, Richland | 32 min |
| Oct 18, 4:08 AM CDT | Severe Thunderstorm Warning | ILX | Coles, Cumberland, Shelby | 37 min |
| Oct 18, 4:20 AM CDT | Severe Thunderstorm Warning | ILX | Crawford, Jasper, Lawrence, Richland | 40 min |
| Oct 18, 4:34 AM CDT | Tornado Warning | ILX | Coles, Douglas | 26 min |
| Oct 18, 4:51 AM CDT | Severe Thunderstorm Warning | ILX | Champaign, Douglas, Edgar, Vermilion | 39 min |
| Oct 18, 4:53 AM CDT | Severe Thunderstorm Warning | ILX | Clark, Edgar | 29 min |
| Oct 18, 5:28 AM CDT | Severe Thunderstorm Warning | ILX | Vermilion | 32 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Lincoln, IL (KILX), launched 00:00Z, 7.0 hours before the alert went out and 80 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
- 579 J/kg
- Mixed-layer CIN
- -45 J/kg
- Mixed-layer LCL
- 645 m above ground
- 0-6 km bulk shear
- 59 kt
- 0-1 km storm-relative helicity
- 336 m²/s²
- 0-3 km storm-relative helicity
- 386 m²/s²
- Significant tornado parameter
- 1.4
- Supercell composite
- 7.2
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 180658
SEL9
SPC WW 180658
ILZ000-181400-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 719
NWS STORM PREDICTION CENTER NORMAN OK
155 AM CDT THU OCT 18 2007
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
CENTRAL ILLINOIS
EFFECTIVE THIS THURSDAY MORNING FROM 155 AM UNTIL 900 AM CDT.
TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH NORTHWEST OF
PEORIA ILLINOIS TO 30 MILES EAST OF SALEM ILLINOIS. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...CONTINUE...WW 715...WW 716...WW
717...WW 718...
DISCUSSION...BAND OF LOW-TOPPED STORMS OVER WRN IL EXPECTED TO
CONTINUE E INTO CNTRL IL LATER THIS MORNING AS EMBEDDED STORMS MOVE
MORE RAPIDLY NNE ALONG IT. CONVECTIVE SYSTEM IS IN ENVIRONMENT OF
WEAK SFC-BASED INSTABILITY BUT VERY STRONG LOW AND DEEP LYR
SHEAR...AND IS BEING FORCED...IN PART...BY ASCENT ASSOCIATED WITH
ERN KS UPR TROUGH. AS KS TROUGH ASSUMES MORE OF A NEGATIVE TILT AND
CONTINUES NNE OVER THE NEXT FEW HOURS...FORCING MAY BE SUFFICIENT TO
MAINTAIN SQLN AND ASSOCIATED SVR WIND/ISOLATED TORNADO THREAT.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
400. MEAN STORM MOTION VECTOR 21040.
...CORFIDISPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 17, 7:57 PM CDT | Mesoscale Discussion | SPC | Adams, Brown, Fulton, Hancock, Henderson, McDonough and 3 more | 63 min |
| Oct 17, 10:56 PM CDT | Mesoscale Discussion | SPC | Adams, Alexander, Bond, Brown, Calhoun, Cass and 34 more | 64 min |
| Oct 17, 11:40 PM CDT | Tornado Watch | SPC | Alexander, Bond, Calhoun, Clinton, Fayette, Greene and 13 more | 4 hr |
| Oct 18, 2:02 AM CDT | Mesoscale Discussion | SPC | Bond, Calhoun, Christian, Clinton, Fayette, Greene and 14 more | 58 min |
| Oct 18, 2:27 AM CDT | Tornado Watch | SPC | Edwards, Franklin, Gallatin, Hamilton, Hardin, Jefferson and 9 more | 4 hr |
| Oct 18, 4:08 AM CDT | Mesoscale Discussion | SPC | Alexander, Champaign, Clark, Clay, Coles, Crawford and 34 more | 67 min |
| Oct 18, 4:37 AM CDT | Tornado Watch | SPC | Ford, Iroquois, Kankakee | 3 hr |
| Oct 18, 11:36 AM CDT | Mesoscale Discussion | SPC | Boone, Carroll, Kane, McHenry, Ogle, Stephenson and 1 more | 2 hr |
| Oct 18, 1:31 PM CDT | Tornado Watch | SPC | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more | 9 hr |
| Oct 18, 1:44 PM CDT | Mesoscale Discussion | SPC | Champaign, Clark, Clay, Coles, Crawford, Cumberland and 23 more | 2 hr |
| Oct 18, 3:23 PM CDT | Tornado Watch | SPC | Bond, Champaign, Christian, Clark, Clay, Clinton and 28 more | 8 hr |
| Oct 18, 5:39 PM CDT | Mesoscale Discussion | SPC | Alexander, Gallatin, Hamilton, Hardin, Johnson, Massac and 6 more | 66 min |
| Oct 18, 6:34 PM CDT | Mesoscale Discussion | SPC | Champaign, Clark, Clay, Clinton, Coles, Crawford and 16 more | 116 min |
| Oct 18, 10:26 AM CDT | Mesoscale Discussion | SPC | Clark, Crawford, Floyd, Harrison, Perry, Spencer | 2 hr |
| Oct 18, 1:59 PM CDT | Mesoscale Discussion | SPC | Allen, Cass, DeKalb, Elkhart, Fulton, Huntington and 13 more | 61 min |
Nearby
Tornado Watches in Illinois, 2007Every tornado watch in 2007
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.