Alert archive / Iowa / Mesoscale Discussions in 2016

Mesoscale Discussion 1695

September 15, 20168 counties in Iowa; 8 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Sep 15, 2016, 7:17 PM CDT for 8 counties in Iowa; 8 counties in Nebraska. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued
Sep 15, 2016, 7:17 PM CDT (00:17 UTC)
Expired
Sep 15, 2016, 8:45 PM CDT
In force
88 min
Issued by
the Storm Prediction Center

Counties Calhoun County, IA, Carroll County, IA, Crawford County, IA, Harrison County, IA, Ida County, IA, Monona County, IA, Sac County, IA, Woodbury County, IA, Burt County, NE, Colfax County, NE, Cuming County, NE, Dodge County, NE, Platte County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE

The radar

The Omaha radar (KOAX), 97 km from the middle of the area, began a volume at 00:21 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

Omaha, NE (KOAX), launched 00:00Z, 0.3 hours before the alert went out and 97 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, Omaha, NE at 00:00Z on 2016-09-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2247 joules per kilogram.LCLEL10008507005003002001001 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, Omaha, NE at 00:00Z on 2016-09-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 153 square meters per square second.193958Sfc1 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
2247 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
1154 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
153 m²/s²
0-3 km storm-relative helicity
172 m²/s²
Significant tornado parameter
1.5
Supercell composite
17.1

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 15, 7:48 PM CDTMesoscale DiscussionSPCAdams, Buffalo, Clay, Dawson, Fillmore, Franklin and 21 more117 min
Sep 15, 9:23 PM CDTMesoscale DiscussionSPCButler, Cass, Clay, Colfax, Dodge, Douglas and 21 more2 hr

Nearby

Mesoscale Discussions in Iowa, 2016Mesoscale Discussions in Nebraska, 2016Every mesoscale discussion 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.