Alert archive / Illinois / Tornado Watches in 2017
Tornado Watch 42
The Storm Prediction Center issued this tornado watch at Feb 28, 2017, 2:57 PM CST for 4 states. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 28, 2017, 2:57 PM CST (20:57 UTC)
- Expired
- Feb 28, 2017, 10:00 PM CST
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 60 kt
All 101 counties
Cedar County, IA, Clinton County, IA, Des Moines County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Van Buren County, IA, Washington County, IA, Adams County, IL, Boone County, IL, Brown County, IL, Bureau County, IL, Carroll County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Coles County, IL, Cook County, IL, Crawford County, IL, Cumberland County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Edgar County, IL, Effingham County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Jasper County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, Lake County, IL, LaSalle County, IL, Lawrence County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McHenry County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Morgan County, IL, Moultrie County, IL, Ogle County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Richland County, IL, Rock Island County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Benton County, IN, Jasper County, IN, Lake County, IN, Newton County, IN, Porter County, IN, Audrain County, MO, Clark County, MO, Knox County, MO, Lewis County, MO, Marion County, MO, Monroe County, MO, Pike County, MO, Ralls County, MO, Scotland County, MO, Shelby County, MO
The radar
The Quad Cities radar (KDVN), 69 km from the middle of the area, began a volume at 21:00 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
- 50%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 60%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
70 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 3:04 PM CST | Severe Thunderstorm Warning | DVN | Hancock, Henderson, McDonough | 41 min |
| Feb 28, 3:26 PM CST | Severe Thunderstorm Warning | DVN | Iowa, Johnson, Keokuk, Washington | 36 min |
| Feb 28, 3:28 PM CST | Tornado Warning | DVN | Rock Island | 47 min |
| Feb 28, 3:35 PM CST | Severe Thunderstorm Warning | ILX | Stark | 25 min |
| Feb 28, 3:44 PM CST | Severe Thunderstorm Warning | DVN | Hancock, Henderson, McDonough, Warren | 46 min |
| Feb 28, 3:50 PM CST | Severe Thunderstorm Warning | ILX | Knox | 26 min |
| Feb 28, 3:51 PM CST | Severe Thunderstorm Warning | DVN | Cedar, Johnson, Muscatine | 39 min |
| Feb 28, 3:54 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 51 min |
| Feb 28, 4:01 PM CST | Severe Thunderstorm Warning | DVN | Cedar, Clinton, Scott | 59 min |
| Feb 28, 4:02 PM CST | Tornado Warning | DVN | Whiteside | 22 min |
| Feb 28, 4:10 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Henry | 35 min |
| Feb 28, 4:11 PM CST | Severe Thunderstorm Warning | ILX | Knox | 36 min |
| Feb 28, 4:14 PM CST | Severe Thunderstorm Warning | LOT | LaSalle | 46 min |
| Feb 28, 4:23 PM CST | Severe Thunderstorm Warning | DVN | Carroll, Whiteside | 67 min |
| Feb 28, 4:27 PM CST | Tornado Warning | LOT | LaSalle | 48 min |
| Feb 28, 4:33 PM CST | Severe Thunderstorm Warning | ILX | Morgan, Scott | 29 min |
| Feb 28, 4:41 PM CST | Severe Thunderstorm Warning | LOT | Lee, Ogle | 34 min |
| Feb 28, 4:42 PM CST | Tornado Warning | DVN | Bureau, Putnam | 14 min |
| Feb 28, 4:44 PM CST | Severe Thunderstorm Warning | ILX | Marshall, Peoria, Stark | 51 min |
| Feb 28, 4:46 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 44 min |
| Feb 28, 4:46 PM CST | Tornado Warning | DVN | Whiteside | 15 min |
| Feb 28, 4:47 PM CST | Tornado Warning | DVN | Putnam | 8 min |
| Feb 28, 4:51 PM CST | Tornado Warning | LOT | Grundy, Kendall, LaSalle | 39 min |
| Feb 28, 5:05 PM CST | Tornado Warning | ILX | Marshall, Peoria, Woodford | 25 min |
| Feb 28, 5:13 PM CST | Severe Thunderstorm Warning | LOT | LaSalle | 47 min |
| Feb 28, 5:15 PM CST | Severe Thunderstorm Warning | LOT | DeKalb, Lee, Ogle | 45 min |
| Feb 28, 5:19 PM CST | Severe Thunderstorm Warning | DVN | Iowa, Keokuk, Washington | 26 min |
| Feb 28, 5:28 PM CST | Tornado Warning | ILX | Marshall, Woodford | 32 min |
| Feb 28, 5:28 PM CST | Severe Thunderstorm Warning | LOT | Grundy, Kendall, Will | 47 min |
| Feb 28, 5:28 PM CST | Severe Thunderstorm Warning | DVN | Cedar, Johnson | 29 min |
| Feb 28, 5:32 PM CST | Severe Thunderstorm Warning | ILX | Marshall | 28 min |
| Feb 28, 5:36 PM CST | Tornado Warning | ILX | Christian | 24 min |
| Feb 28, 5:36 PM CST | Tornado Warning | LOT | LaSalle, Livingston | 39 min |
| Feb 28, 5:44 PM CST | Severe Thunderstorm Warning | DVN | Johnson | 31 min |
| Feb 28, 5:51 PM CST | Severe Thunderstorm Warning | LOT | Cook, DeKalb, DuPage, Kane, Lake, McHenry | 39 min |
| Feb 28, 6:00 PM CST | Severe Thunderstorm Warning | LOT | Cook, Grundy, Kendall, Will | 45 min |
| Feb 28, 6:01 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 29 min |
| Feb 28, 6:05 PM CST | Severe Thunderstorm Warning | DVN | Cedar, Johnson, Muscatine | 40 min |
| Feb 28, 6:13 PM CST | Tornado Warning | LOT | Grundy, LaSalle, Livingston | 32 min |
| Feb 28, 6:24 PM CST | Severe Thunderstorm Warning | LOT | LaSalle | 51 min |
| Feb 28, 6:27 PM CST | Severe Thunderstorm Warning | ILX | Shelby | 28 min |
| Feb 28, 6:31 PM CST | Severe Thunderstorm Warning | LOT | Lake, Porter | 59 min |
| Feb 28, 6:37 PM CST | Severe Thunderstorm Warning | DVN | Cedar, Clinton, Scott | 53 min |
| Feb 28, 6:44 PM CST | Severe Thunderstorm Warning | LOT | Kankakee, Will | 46 min |
| Feb 28, 6:44 PM CST | Severe Thunderstorm Warning | LOT | Cook, Will | 46 min |
| Feb 28, 6:54 PM CST | Severe Thunderstorm Warning | ILX | Coles, Douglas, Moultrie | 10 min |
| Feb 28, 7:04 PM CST | Severe Thunderstorm Warning | LOT | Grundy, Kendall, Will | 41 min |
| Feb 28, 7:24 PM CST | Severe Thunderstorm Warning | DVN | Des Moines, Henry, Lee, Louisa | 51 min |
| Feb 28, 7:31 PM CST | Severe Thunderstorm Warning | LOT | Porter | 29 min |
| Feb 28, 7:38 PM CST | Severe Thunderstorm Warning | ILX | Clay, Jasper, Richland | 67 min |
| Feb 28, 7:41 PM CST | Severe Thunderstorm Warning | LOT | LaSalle | 34 min |
| Feb 28, 7:45 PM CST | Severe Thunderstorm Warning | LOT | Cook, Kankakee, Will | 45 min |
| Feb 28, 7:57 PM CST | Severe Thunderstorm Warning | LSX | Marion, Monroe, Shelby | 48 min |
| Feb 28, 8:04 PM CST | Severe Thunderstorm Warning | LOT | Grundy, LaSalle, Will | 26 min |
| Feb 28, 8:18 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Henry | 28 min |
| Feb 28, 8:18 PM CST | Severe Thunderstorm Warning | DVN | Bureau | 27 min |
| Feb 28, 8:22 PM CST | Severe Thunderstorm Warning | DVN | Mercer, Rock Island | 23 min |
| Feb 28, 8:29 PM CST | Severe Thunderstorm Warning | LSX | Adams, Pike | 33 min |
| Feb 28, 8:32 PM CST | Severe Thunderstorm Warning | DVN | Henry, Mercer, Rock Island | 30 min |
| Feb 28, 8:34 PM CST | Tornado Warning | ILX | Clay, Richland | 41 min |
| Feb 28, 8:35 PM CST | Severe Thunderstorm Warning | LOT | DeKalb, Kendall, LaSalle, Lee | 40 min |
| Feb 28, 8:37 PM CST | Tornado Warning | LSX | Adams, Pike | 27 min |
| Feb 28, 8:57 PM CST | Severe Thunderstorm Warning | LOT | Cook, Will | 37 min |
| Feb 28, 9:04 PM CST | Tornado Warning | ILX | Crawford, Lawrence, Richland | 41 min |
| Feb 28, 9:07 PM CST | Severe Thunderstorm Warning | LSX | Adams, Brown, Pike | 38 min |
| Feb 28, 9:19 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 41 min |
| Feb 28, 9:20 PM CST | Tornado Warning | DVN | Bureau, Putnam | 40 min |
| Feb 28, 9:23 PM CST | Tornado Warning | LSX | Brown, Pike | 22 min |
| Feb 28, 9:29 PM CST | Tornado Warning | ILX | Cass, Schuyler | 23 min |
| Feb 28, 9:34 PM CST | Severe Thunderstorm Warning | LOT | LaSalle | 56 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
Davenport, (KDVN), launched 12:00Z, 9.0 hours before the alert went out and 68 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
- 30 J/kg
- Mixed-layer CIN
- -241 J/kg
- Mixed-layer LCL
- 771 m above ground
- 0-6 km bulk shear
- 80 kt
- 0-1 km storm-relative helicity
- 223 m²/s²
- 0-3 km storm-relative helicity
- 294 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
615
WWUS20 KWNS 282055
SEL2
SPC WW 282055
IAZ000-ILZ000-INZ000-MOZ000-LMZ000-010400-
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 42
NWS Storm Prediction Center Norman OK
300 PM CST Tue Feb 28 2017
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Southeast Iowa
Northern and Central Illinois
Northwest Indiana
Northeast Missouri
Lake Michigan
* Effective this Tuesday afternoon and evening from 300 PM until
1000 PM CST.
* Primary threats include...
A few tornadoes possible
Scattered large hail likely with isolated very large hail events
to 3 inches in diameter possible
Scattered damaging wind gusts to 70 mph possible
SUMMARY...Scattered thunderstorms are expected to form this
afternoon and early evening across the watch area. Conditions
appear favorable for large hail in the stronger cells, along with
the risk for isolated tornadoes.
The tornado watch area is approximately along and 120 statute miles
north and south of a line from 35 miles south of Ottumwa IA to 30
miles north of Lafayette IN. 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 41...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 3 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean
storm motion vector 25035.
...HartSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 1:46 PM CST | Mesoscale Discussion | SPC | Alexander, Franklin, Jackson, Jefferson, Johnson, Massac and 8 more | 2 hr |
| Feb 28, 2:03 PM CST | Mesoscale Discussion | SPC | Bureau, DeKalb, DuPage, Ford, Fulton, Grundy and 24 more | 2 hr |
| Feb 28, 2:19 PM CST | Tornado Watch | SPC | Alexander, Bond, Calhoun, Clinton, Edwards, Fayette and 27 more | 7 hr |
| Feb 28, 5:24 PM CST | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 28 more | 96 min |
| Feb 28, 5:28 PM CST | Mesoscale Discussion | SPC | Alexander, Jackson, Johnson, Massac, Pope, Pulaski and 2 more | 2 hr |
| Feb 28, 3:40 PM CST | Tornado Watch | SPC | Dunklin, Pemiscot | 6 hr |
Nearby
Tornado Watches in Illinois, 2017Tornado Watches in Iowa, 2017Tornado Watches in Missouri, 2017Every tornado watch in 2017
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.