Alert archive / Iowa / Flash Flood Watches in 2019

Flash Flood Watch 11, NWS Des Moines, IA

July 17, 20196 counties in Iowa

NWS Des Moines, IA issued this flash flood watch at Jul 17, 2019, 3:23 AM CDT for 6 counties in Iowa. It took effect at Jul 17, 2019, 7:00 PM CDT. It was in force for 12 hr.

The area

The counties it named.

The facts

Issued: Jul 17, 2019, 3:23 AM CDT (08:23 UTC)
In effect from: Jul 17, 2019, 7:00 PM CDT
Expired: Jul 18, 2019, 6:31 AM CDT
In force: 12 hr
Issued by: NWS Des Moines, IA
Flood severity: None

Counties Black Hawk County, IA, Bremer County, IA, Butler County, IA, Cerro Gordo County, IA, Winnebago County, IA, Worth County, IA

The radar

The Des Moines radar (KDMX), 152 km from the middle of the area, began a volume at 08:24 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

Minneapolis, MN (KMPX), launched 00:00Z, 8.4 hours before the alert went out and 216 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: 756 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 1264 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: -5 m²/s²
0-3 km storm-relative helicity: 43 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

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 Des Moines, IA wrote its last area forecast discussion before this flash flood watch went out at Jul 16, 11:42 PM CDT, 3 hours 41 minutes earlier.

Area forecast discussion, Jul 16, 11:42 PM CDT, 3 hours 41 minutes before

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Hazardous weather outlook, Jul 16, 9:09 PM CDT, 6 hours 14 minutes before

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The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 17, 8:43 AM CDT	Special Weather Statement	DMX	Calhoun, Carroll, Crawford, Pocahontas, Sac	62 min
Jul 17, 9:34 AM CDT	Special Weather Statement	DMX	Boone, Calhoun, Carroll, Greene, Hamilton, Webster	56 min
Jul 17, 10:11 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Audubon, Cass, Guthrie	49 min
Jul 17, 10:16 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Franklin, Hamilton, Hardin, Story, Webster and 1 more	44 min
Jul 17, 10:44 AM CDT	Severe Thunderstorm Warning	DMX	Dallas, Guthrie	46 min
Jul 17, 10:55 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Audubon, Cass, Guthrie	35 min
Jul 17, 12:39 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Decatur, Lucas, Wayne	51 min
Jul 17, 1:54 PM CDT	Special Weather Statement	DMX	Davis	51 min
Jul 17, 3:33 PM CDT	Heat Advisory	DMX	Cerro Gordo, Emmet, Hancock, Kossuth, Palo Alto, Winnebago and 1 more	36 hr

Nearby

Flash Flood Watches in Iowa, 2019 Every flash flood watch in 2019

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.