Alert archive / Illinois / Flash Flood Watches in 2016

Flash Flood Watch 2, NWS Chicago, IL

June 21, 201614 counties in Illinois; Lake County, Porter County, Indiana

NWS Chicago, IL issued this flash flood watch at Jun 21, 2016, 3:35 PM CDT for 14 counties in Illinois; Lake County, Porter County, Indiana. It took effect at Jun 22, 2016, 4:00 AM CDT. It was in force for 21 hr.

The area

The counties it named.

The facts

Issued
Jun 21, 2016, 3:35 PM CDT (20:35 UTC)
In effect from
Jun 22, 2016, 4:00 AM CDT
Expired
Jun 23, 2016, 12:44 AM CDT
In force
21 hr
Issued by
NWS Chicago, IL
Flood severity
None

Counties Boone County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, McHenry County, IL, Ogle County, IL, Winnebago County, IL, Lake County, IN, Porter County, IN

The radar

The Chicago radar (KLOT), 33 km from the middle of the area, began a volume at 20:35 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

Davenport, (KDVN), launched 12:00Z, 8.6 hours before the alert went out and 173 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 2016-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2016-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -73 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
2054 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
-73 m²/s²
0-3 km storm-relative helicity
36 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 flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Chicago, IL wrote its last area forecast discussion before this flash flood watch went out at Jun 21, 3:11 PM CDT, 24 minutes earlier.

Area forecast discussion, Jun 21, 3:11 PM CDT, 24 minutes before
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Hazardous weather outlook, Jun 21, 12:43 PM CDT, 2 hours 52 minutes before
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  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
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        Please try again in a few minutes.
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The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 9:01 PM CDTSpecial Weather StatementLOTFord29 min

Nearby

Flash Flood Watches in Illinois, 2016Flash Flood Watches in Indiana, 2016Every flash flood watch in 2016

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.