Alert archive / South Dakota / Mesoscale Discussions in 2012

Mesoscale Discussion 537

April 14, 20124 states

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2012, 7:51 PM CDT for 4 states. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Apr 14, 2012, 7:51 PM CDT (00:51 UTC)
Expired
Apr 14, 2012, 9:15 PM CDT
In force
84 min
Issued by
the Storm Prediction Center
All 42 counties

Cherokee County, IA, Ida County, IA, Lyon County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Nobles County, MN, Pipestone County, MN, Rock County, MN, Boyd County, NE, Burt County, NE, Cedar County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Knox County, NE, Pierce County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE, Aurora County, SD, Bon Homme County, SD, Charles Mix County, SD, Clay County, SD, Davison County, SD, Douglas County, SD, Hanson County, SD, Hutchinson County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 69 km from the middle of the area, began a volume at 00:53 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.9 hours before the alert went out and 212 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 2012-04-15Temperature 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, Omaha, NE at 00:00Z on 2012-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 276 square meters per square second.1939587897Sfc1 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
871 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
276 m²/s²
0-3 km storm-relative helicity
483 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

240 
ACUS11 KWNS 150052
SWOMCD
SPC MCD 150051
MNZ000-IAZ000-NEZ000-SDZ000-150215-

MESOSCALE DISCUSSION 0537
NWS STORM PREDICTION CENTER NORMAN OK
0751 PM CDT SAT APR 14 2012

AREAS AFFECTED...NE NEB...SERN SOUTH DAKOTA NW IA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 150051Z - 150215Z

STRONGEST SURFACE PRESSURE FALLS ACROSS THE CENTRAL PLAINS HAVE
RECENTLY BECOME FOCUSED ACROSS THE MID MISSOURI VALLEY AREA
...AROUND YANKTON/SIOUX FALLS AND SIOUX CITY.  THIS IS LIKELY
REFLECTIVE OF A STRENGTHENING LOWER/MID TROPOSPHERIC WARM ADVECTION
REGIME...WHICH PROBABLY WILL SUPPORT INCREASING CONVECTIVE
DEVELOPMENT THROUGH 02-04Z.  THIS ACTIVITY WILL BE ROOTED WITHIN A
MOISTENING LAYER ABOVE A LINGERING NEAR SURFACE STABLE LAYER...TO
THE NORTH OF A WARM FRONT.  WHILE IT IS POSSIBLE THAT MID-LEVEL
INSTABILITY MAY BE SUFFICIENT TO SUPPORT THE RISK FOR SOME LARGE
HAIL IN STRONGER STORMS...THE SEVERE POTENTIAL CURRENTLY SEEMS TOO
LOW TO REQUIRE A WATCH.

..KERR.. 04/15/2012

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

ATTN...WFO...DMX...FSD...OAX...LBF...

LAT...LON   43879900 44399719 44269603 43449530 42259545 41489616
            41979736 42699823 42849891 43879900

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 14, 7:50 PM CDTMesoscale DiscussionSPCBenton, Buchanan, Cedar, Delaware, Henry, Iowa and 13 more55 min
Apr 14, 8:41 PM CDTSevere Thunderstorm WatchSPCCedar, Clinton, Des Moines, Henry, Iowa, Jackson and 9 more4 hr
Apr 14, 9:54 PM CDTMesoscale DiscussionSPCCedar, Clinton, Jackson, Jones, Louisa, Muscatine and 1 more96 min
Apr 14, 10:09 PM CDTSevere Thunderstorm WatchSPCFremont, Harrison, Mills, Monona, Montgomery, Page and 3 more6 hr
Apr 14, 11:28 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Boone, Carroll and 28 more92 min
Apr 15, 3:25 AM CDTMesoscale DiscussionSPCAdams, Audubon, Cass, Fremont, Harrison, Mills and 5 more95 min
Apr 15, 1:56 PM CDTMesoscale DiscussionSPCAudubon, Boone, Buena Vista, Butler, Calhoun, Carroll and 28 more94 min
Apr 15, 3:37 PM CDTTornado WatchSPCCerro Gordo, Chickasaw, Clay, Dickinson, Emmet, Floyd and 8 more7 hr
Apr 15, 12:25 PM CDTMesoscale DiscussionSPCBenton, Big Stone, Chippewa, Douglas, Kandiyohi, Lac qui Parle and 13 more65 min
Apr 15, 5:54 PM CDTMesoscale DiscussionSPCAnoka, Carver, Chisago, Dakota, Hennepin, Ramsey and 3 more96 min
Apr 15, 1:18 PM CDTMesoscale DiscussionSPCAntelope, Cedar, Garfield, Greeley, Knox, Pierce and 3 more87 min

Nearby

Mesoscale Discussions in South Dakota, 2012Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Iowa, 2012Every mesoscale discussion in 2012

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.