Alert archive / Illinois / Tornado Watches in 2015
Tornado Watch 112
The Storm Prediction Center issued this tornado watch at Apr 25, 2015, 12:55 PM CDT for 4 states. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 25, 2015, 12:55 PM CDT (17:55 UTC)
- Expired
- Apr 25, 2015, 8:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 88 counties
Alexander County, IL, Bond County, IL, Calhoun County, IL, Clay County, IL, Clinton County, IL, Edwards County, IL, Fayette County, IL, Franklin County, IL, Gallatin County, IL, Greene County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Jersey County, IL, Johnson County, IL, Lawrence County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Massac County, IL, Monroe County, IL, Montgomery County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Union County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Gibson County, IN, Pike County, IN, Posey County, IN, Spencer County, IN, Vanderburgh County, IN, Warrick County, IN, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Daviess County, KY, Fulton County, KY, Graves County, KY, Henderson County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, McLean County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Union County, KY, Webster County, KY, Bollinger County, MO, Cape Girardeau County, MO, City of Saint Louis, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Lincoln County, MO, Madison County, MO, Mississippi County, MO, Montgomery County, MO, New Madrid County, MO, Perry County, MO, Pike County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Scott County, MO, Stoddard County, MO, Warren County, MO, Washington County, MO
The radar
The St Louis radar (KLSX), 103 km from the middle of the area, began a volume at 17:55 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
- 50%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 3:57 PM CDT | Severe Thunderstorm Warning | PAH | Franklin, Hamilton, Saline, Williamson | 33 min |
| Apr 25, 4:21 PM CDT | Severe Thunderstorm Warning | PAH | Gallatin, Saline, White | 24 min |
| Apr 25, 4:30 PM CDT | Severe Thunderstorm Warning | PAH | Franklin, Jackson, Williamson | 23 min |
| Apr 25, 4:40 PM CDT | Severe Thunderstorm Warning | PAH | Gallatin, White | 50 min |
| Apr 25, 5:18 PM CDT | Severe Thunderstorm Warning | PAH | Henderson, Union, Webster | 27 min |
| Apr 25, 5:21 PM CDT | Severe Thunderstorm Warning | PAH | Daviess | 24 min |
| Apr 25, 5:24 PM CDT | Tornado Warning | PAH | Henderson | 18 min |
| Apr 25, 5:39 PM CDT | Severe Thunderstorm Warning | PAH | Daviess, Henderson, Hopkins, McLean, Webster | 40 min |
| Apr 25, 5:43 PM CDT | Severe Thunderstorm Warning | PAH | Hardin, Pope | 47 min |
| Apr 25, 6:05 PM CDT | Severe Thunderstorm Warning | PAH | Daviess, McLean | 25 min |
| Apr 25, 6:12 PM CDT | Severe Thunderstorm Warning | PAH | Caldwell, Crittenden, Hopkins | 48 min |
| Apr 25, 6:37 PM CDT | Severe Thunderstorm Warning | PAH | Christian, Hopkins, Muhlenberg | 38 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 12:00Z, 5.9 hours before the alert went out and 224 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 735 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 130 m²/s²
- 0-3 km storm-relative helicity
- 137 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
426
WWUS20 KWNS 251754
SEL2
SPC WW 251754
ILZ000-INZ000-KYZ000-MOZ000-260100-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 112
NWS STORM PREDICTION CENTER NORMAN OK
1255 PM CDT SAT APR 25 2015
THE NWS STORM PREDICTION CENTER HAS ISSUED A
* TORNADO WATCH FOR PORTIONS OF
SOUTHERN ILLINOIS
EXTREME SOUTHWEST INDIANA
WESTERN KENTUCKY
EAST-CENTRAL AND SOUTHEAST MISSOURI
* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 1255 PM
UNTIL 800 PM CDT.
* PRIMARY THREATS INCLUDE...
A FEW TORNADOES POSSIBLE
SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2
INCHES IN DIAMETER POSSIBLE
ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
SUMMARY...THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND
INTENSITY FROM WEST TO EAST ACROSS THE WATCH AREA THIS AFTERNOON.
SEVERE STORMS INCLUDING SUPERCELLS APPEAR LIKELY WITH A RISK FOR A
FEW TORNADOES...LARGE HAIL AND DAMAGING WINDS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 55 MILES WEST SOUTHWEST OF
SAINT LOUIS MISSOURI TO 15 MILES SOUTH SOUTHEAST OF OWENSBORO
KENTUCKY. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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 109...WW 110...WW 111...
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 28030.
...MEADSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 12:22 PM CDT | Mesoscale Discussion | SPC | Alexander, Clinton, Edwards, Franklin, Gallatin, Hamilton and 20 more | 2 hr |
| Apr 25, 3:25 PM CDT | Mesoscale Discussion | SPC | Alexander, Bond, Clay, Clinton, Edwards, Fayette and 25 more | 2 hr |
| Apr 25, 4:57 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Barren, Bell, Boyle, Breckinridge and 40 more | 6 hr |
| Apr 25, 6:14 PM CDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Boyle, Butler, Casey and 29 more | 91 min |
Nearby
Tornado Watches in Illinois, 2015Tornado Watches in Missouri, 2015Tornado Watches in Kentucky, 2015Every tornado watch in 2015
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.