Alert archive / Missouri / Areal Flood Advisories in 2021
Areal Flood Advisory 68, NWS St. Louis, MO
NWS St. Louis, MO issued this areal flood advisory at Jul 18, 2021, 7:44 AM CDT for Madison County, Missouri. It was in force for 3 hr.
The area
The counties it named.
The facts
- Issued
- Jul 18, 2021, 7:44 AM CDT (12:44 UTC)
- Expired
- Jul 18, 2021, 10:45 AM CDT
- In force
- 3 hr
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
County Madison County, MO
The radar
The St Louis radar (KLSX), 139 km from the middle of the area, began a volume at 12:46 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
Little Rock, AR (KLZK), launched 12:00Z, 0.7 hours before the alert went out and 297 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
- 567 J/kg
- Mixed-layer CIN
- -28 J/kg
- Mixed-layer LCL
- 611 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 131 m²/s²
- 0-3 km storm-relative helicity
- 135 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.7
What forecasters said that day
The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS St. Louis, MO wrote its last area forecast discussion before this areal flood advisory went out at Jul 18, 6:42 AM CDT, 1 hour 2 minutes earlier.
Area forecast discussion, Jul 18, 6:42 AM CDT, 1 hour 2 minutes before
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</html>Hazardous weather outlook, Jul 18, 3:33 AM CDT, 4 hours 11 minutes before
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<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>
<p id="message2">
Please try again in a few minutes.
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If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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</html>The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 7:09 PM CDT | Areal Flood Advisory | LSX | Madison, Saint Francois | 97 min |
| Jul 18, 2:14 AM CDT | Areal Flood Advisory | LSX | Sainte Genevieve, Saint Francois | 3 hr |
| Jul 18, 3:06 AM CDT | Areal Flood Advisory | LSX | Crawford | 3 hr |
| Jul 18, 4:24 AM CDT | Areal Flood Advisory | LSX | Washington | 3 hr |
Nearby
Areal Flood Advisories in Missouri, 2021Every areal flood advisory in 2021
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.