Alert archive / Iowa / Mesoscale Discussions in 2016

Mesoscale Discussion 441

April 24, 20164 states

The Storm Prediction Center issued this mesoscale discussion at Apr 24, 2016, 8:45 PM CDT for 4 states. It was in force for 60 min.

The area

The outline as issued.

The facts

Issued
Apr 24, 2016, 8:45 PM CDT (01:45 UTC)
Expired
Apr 24, 2016, 9:45 PM CDT
In force
60 min
Issued by
the Storm Prediction Center
All 43 counties

Adams County, IA, Audubon County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Clay County, IA, Crawford County, IA, Fremont County, IA, Harrison County, IA, Ida County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Palo Alto County, IA, Pocahontas County, IA, Pottawattamie County, IA, Sac County, IA, Shelby County, IA, Taylor County, IA, Atchison County, KS, Brown County, KS, Dickinson County, KS, Doniphan County, KS, Douglas County, KS, Geary County, KS, Jackson County, KS, Jefferson County, KS, Leavenworth County, KS, Morris County, KS, Nemaha County, KS, Pottawatomie County, KS, Riley County, KS, Saline County, KS, Shawnee County, KS, Wabaunsee County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Holt County, MO, Nodaway County, MO, Nemaha County, NE, Richardson County, NE

The radar

The Omaha radar (KOAX), 110 km from the middle of the area, began a volume at 01:47 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, 1.8 hours before the alert went out and 110 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 2016-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1046 joules per kilogram.LCLLFCEL10008507005003002001001 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 2016-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 236 square meters per square second.19395878Sfc1 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
1046 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
1404 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
236 m²/s²
0-3 km storm-relative helicity
338 m²/s²
Significant tornado parameter
1.2
Supercell composite
16.1

Open this sounding in Storm Lab

The text

As transmitted.

840 
ACUS11 KWNS 250145
SWOMCD
SPC MCD 250145 
IAZ000-MOZ000-KSZ000-NEZ000-250245-

MESOSCALE DISCUSSION 0441
NWS STORM PREDICTION CENTER NORMAN OK
0845 PM CDT SUN APR 24 2016

AREAS AFFECTED...NORTHEAST KS TO WESTERN IA

CONCERNING...TORNADO WATCH 101...102...

VALID 250145Z - 250245Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 101...102...CONTINUES.

SUMMARY...PRIMARY SEVERE THREAT IS ORIENTING ITSELF ALONG A CORRIDOR
FROM NORTHEAST KS INTO NORTHWEST MO.  LARGE HAIL WILL BECOME THE
MAIN RISK...ALTHOUGH DAMAGING WINDS ARE ALSO POSSIBLE.

DISCUSSION...EARLIER SUPERCELL ACTIVITY THAT EVOLVED ALONG THE
DRYLINE ACROSS SRN NEBRASKA AND NRN KS HAS CONGEALED INTO A SW-NE
ORIENTED BAND OF SEVERE CONVECTION OVER NERN KS.  AS LLJ INCREASES
FROM NERN KS INTO SRN IA THIS DEVELOPING SQUALL LINE SHOULD
PROPAGATE EWD TOWARD THE MO RIVER.  LATEST HAIL ALGORITHM SUGGESTS
HAIL GREATER THAN ONE INCH IS COMMON FROM SALINE INTO POTTAWATOMIE
COUNTY KS. AS CONVECTION SPREADS EAST OF THE MO RIVER WEAKER
INSTABILITY SHOULD LIMIT SEVERE THREAT.

..DARROW.. 04/25/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...DMX...EAX...FSD...OAX...TOP...ICT...

LAT...LON   38619805 39629661 40369602 41999582 43179546 43229464
            41339453 39939461 39009504 38469623 38619805

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 2:17 PM CDTSevere Thunderstorm WatchSPCClinton, Scott8 hr
Apr 25, 3:50 PM CDTMesoscale DiscussionSPCBanner, Kimball, Scotts Bluff, Sioux115 min

Nearby

Mesoscale Discussions in Iowa, 2016Mesoscale Discussions in Kansas, 2016Mesoscale Discussions in Missouri, 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.