Alert archive / Illinois / Areal Flood Advisories in 2017
Areal Flood Advisory 9, NWS St. Louis, MO
NWS St. Louis, MO issued this areal flood advisory at Aug 1, 2017, 6:25 PM CDT for Randolph County, Illinois. It was in force for 3 hr.
The area
The counties it named.
The facts
- Issued
- Aug 1, 2017, 6:25 PM CDT (23:25 UTC)
- Expired
- Aug 1, 2017, 9:30 PM CDT
- In force
- 3 hr
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
County Randolph County, IL
The radar
The St Louis radar (KLSX), 104 km from the middle of the area, began a volume at 23:25 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, 11.4 hours before the alert went out and 256 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
- 502 J/kg
- Mixed-layer CIN
- -42 J/kg
- Mixed-layer LCL
- 1129 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 49 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 5:05 PM CDT | Special Weather Statement | LSX | Monroe | 40 min |
Nearby
Areal Flood Advisories in Illinois, 2017Every areal flood advisory 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.