Alert archive / Illinois / Frost Advisories in 2026

Frost Advisory 1, NWS Lincoln, IL

April 18, 202635 counties in Illinois

NWS Lincoln, IL issued this frost advisory at Apr 18, 2026, 1:48 PM CDT for 35 counties in Illinois. It took effect at Apr 19, 2026, 1:00 AM CDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Apr 18, 2026, 1:48 PM CDT (18:48 UTC)
In effect from: Apr 19, 2026, 1:00 AM CDT
Expired: Apr 19, 2026, 8:00 AM CDT
In force: 7 hr
Issued by: NWS Lincoln, IL

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), 42 km from the middle of the area, began a volume at 18:51 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.

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 6.8 hours before the alert went out and 46 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1118 m above ground
0-6 km bulk shear: 71 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: 66 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this frost advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Lincoln, IL wrote its last area forecast discussion before this frost advisory went out at Apr 18, 12:21 PM CDT, 1 hour 27 minutes earlier.

Area forecast discussion, Apr 18, 12:21 PM CDT, 1 hour 27 minutes before

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Hazardous weather outlook, Apr 18, 4:56 AM CDT, 8 hours 52 minutes before

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In the hours before

Local storm report, Apr 18, 8:50 AM CDT, 4 hours 58 minutes before

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Local storm report, Apr 18, 9:12 AM CDT, 4 hours 36 minutes before

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Local storm report, Apr 18, 9:41 AM CDT, 4 hours 7 minutes before

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Local storm report, Apr 18, 11:43 AM CDT, 2 hours 5 minutes before

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Local storm report, Apr 18, 12:58 PM CDT, 50 minutes before

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Local storm report, Apr 18, 1:30 PM CDT, 18 minutes before

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The office that day

Everything else NWS Lincoln, IL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 17, 7:05 PM CDT	Tornado Warning	ILX	Knox, Stark	25 min
Apr 17, 7:13 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Marshall, Peoria, Stark	47 min
Apr 17, 7:21 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Fulton, Knox	54 min
Apr 17, 7:26 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Cass, Fulton, Mason, Morgan, Schuyler, Scott	34 min
Apr 17, 7:30 PM CDT	Tornado Warning	ILX	Marshall, Stark	30 min
Apr 17, 7:36 PM CDT	Tornado Warning	ILX	Fulton	24 min
Apr 17, 7:50 PM CDT	Tornado Warning	ILX	Knox, Marshall, Peoria, Stark	40 min
Apr 17, 7:56 PM CDT	Tornado Warning	ILX	Fulton, Mason	34 min
Apr 17, 7:58 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Cass, Fulton, Knox, Marshall, Mason, Menard and 5 more	49 min
Apr 17, 8:01 PM CDT	Tornado Warning	ILX	Marshall, Peoria, Stark	29 min
Apr 17, 8:02 PM CDT	Tornado Warning	ILX	Fulton, Peoria, Tazewell	28 min
Apr 17, 8:10 PM CDT	Tornado Warning	ILX	Mason, Tazewell	35 min
Apr 17, 8:16 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Cass, DeWitt, Logan, McLean, Mason, Menard and 2 more	59 min
Apr 17, 8:19 PM CDT	Tornado Warning	ILX	Marshall, Peoria, Tazewell, Woodford	41 min
Apr 17, 8:20 PM CDT	Tornado Warning Tornado observed	ILX	Logan, McLean, Mason, Tazewell	40 min
Apr 17, 8:28 PM CDT	Tornado Warning	ILX	Logan, Mason, Menard	32 min
Apr 17, 8:30 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	McLean, Marshall, Tazewell, Woodford	45 min
Apr 17, 8:39 PM CDT	Tornado Warning Tornado observed	ILX	McLean, Tazewell, Woodford	36 min
Apr 17, 8:43 PM CDT	Tornado Warning	ILX	McLean, Tazewell, Woodford	47 min
Apr 17, 8:53 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Christian, Logan, Macon, Sangamon	52 min
Apr 17, 8:54 PM CDT	Tornado Warning	ILX	Marshall, Woodford	21 min
Apr 17, 9:00 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	DeWitt, McLean, Piatt	45 min
Apr 17, 9:01 PM CDT	Tornado Warning	ILX	McLean	44 min
Apr 17, 9:08 PM CDT	Tornado Warning Tornado observed	ILX	DeWitt, Logan, McLean, Macon, Piatt	37 min
Apr 17, 9:27 PM CDT	Severe Thunderstorm Warning	ILX	Macon, Piatt	48 min
Apr 17, 9:37 PM CDT	Severe Thunderstorm Warning	ILX	Champaign	38 min
Apr 17, 9:42 PM CDT	Areal Flood Advisory	ILX	Peoria	3 hr
Apr 17, 9:42 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Piatt	18 min
Apr 17, 9:42 PM CDT	Tornado Warning	ILX	Champaign, Piatt	48 min
Apr 17, 9:46 PM CDT	Severe Thunderstorm Warning	ILX	Champaign, Douglas, Moultrie, Piatt	44 min
Apr 17, 10:11 PM CDT	Severe Thunderstorm Warning	ILX	Vermilion	49 min
Apr 17, 10:15 PM CDT	Severe Thunderstorm Warning	ILX	Champaign	19 min
Apr 17, 11:24 PM CDT	Special Weather Statement	ILX	Christian, Sangamon	36 min
Apr 17, 11:54 PM CDT	Areal Flood Advisory	ILX	Sangamon	2 hr
Apr 18, 1:48 PM CDT	Freeze Watch	ILX	Champaign, DeWitt, Fulton, Knox, Logan, McLean and 8 more	12 hr

Nearby

Frost Advisories in Illinois, 2026 Every frost advisory in 2026

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.