Alert archive / Missouri / Mesoscale Discussions in 2017

Mesoscale Discussion 556

April 25, 20174 states

The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2017, 10:51 PM CDT for 4 states. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued
Apr 25, 2017, 10:51 PM CDT (03:51 UTC)
Expired
Apr 25, 2017, 11:45 PM CDT
In force
54 min
Issued by
the Storm Prediction Center
All 35 counties

Benton County, AR, Boone County, AR, Carroll County, AR, Madison County, AR, Washington County, AR, Cherokee County, KS, Crawford County, KS, Barry County, MO, Barton County, MO, Bates County, MO, Benton County, MO, Camden County, MO, Cedar County, MO, Christian County, MO, Dade County, MO, Dallas County, MO, Greene County, MO, Henry County, MO, Hickory County, MO, Jasper County, MO, Laclede County, MO, Lawrence County, MO, McDonald County, MO, Morgan County, MO, Newton County, MO, Polk County, MO, St. Clair County, MO, Stone County, MO, Taney County, MO, Vernon County, MO, Webster County, MO, Craig County, OK, Delaware County, OK, Mayes County, OK, Ottawa County, OK

The radar

The Springfield radar (KSGF), 47 km from the middle of the area, began a volume at 03:52 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

Springfield, MO (KSGF), launched 00:00Z, 3.9 hours before the alert went out and 58 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, Springfield, MO at 00:00Z on 2017-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 446 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, Springfield, MO at 00:00Z on 2017-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 122 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
446 J/kg
Mixed-layer CIN
-158 J/kg
Mixed-layer LCL
1525 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
122 m²/s²
0-3 km storm-relative helicity
196 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

As transmitted.

067 
ACUS11 KWNS 260351
SWOMCD
SPC MCD 260351 
MOZ000-ARZ000-OKZ000-KSZ000-260445-

Mesoscale Discussion 0556
NWS Storm Prediction Center Norman OK
1051 PM CDT Tue Apr 25 2017

Areas affected...Portions of western Missouri...far southeastern
Kansas...far northeastern Oklahoma...and far northwestern Arkansas

Concerning...Severe Thunderstorm Watch 159...

Valid 260351Z - 260445Z

The severe weather threat for Severe Thunderstorm Watch 159
continues.

SUMMARY...Strong to occasionally severe storms may persist eastward
beyond Watch 159. Areal expansion or new watch issuance may be
needed.

DISCUSSION...A pair of small linear segments has evolved from
eastern Kansas into far western Missouri this evening, aided by
broad large-scale ascent on the eastern fringe of a mid-level
trough. While diurnal cooling has reduced surface-based buoyancy
some, surface temperatures in the upper 60s/lower 70s and modest
low-level moisture are maintaining MLCAPE values around 500-1000
J/kg. Combined with ample south/southwesterly mid-level flow of
50-60 kt, this thermodynamic environment may support a continued
damaging wind threat beyond the eastern edge of the ongoing watch.
As such, areal expansion or new watch issuance could be needed
within the next 30 minutes or so.

..Picca.. 04/26/2017

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...LZK...SGF...EAX...TSA...ICT...

LAT...LON   38359462 38529421 38529311 38399262 37989251 37209262
            36349287 35919351 35989441 36239530 36909523 37699492
            38359462

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 11:27 PM CDTSevere Thunderstorm WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more7 hr
Apr 26, 1:42 AM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Crawford, Franklin, Johnson and 10 more2 hr
Apr 26, 5:37 AM CDTMesoscale DiscussionSPCConway, Crawford, Franklin, Garland, Howard, Johnson and 14 more113 min
Apr 26, 6:00 AM CDTSevere Thunderstorm WatchSPCBaxter, Boone, Carroll, Conway, Crawford, Franklin and 23 more7 hr
Apr 26, 7:29 AM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Conway, Crawford, Franklin and 23 more2 hr
Apr 26, 9:39 AM CDTMesoscale DiscussionSPCArkansas, Baxter, Bradley, Calhoun, Clark, Clay and 47 more36 min
Apr 26, 10:08 AM CDTTornado WatchSPCArkansas, Baxter, Bradley, Calhoun, Clark, Clay and 51 more7 hr
Apr 26, 1:05 PM CDTMesoscale DiscussionSPCClark, Columbia, Dallas, Grant, Hempstead, Hot Spring and 9 more85 min
Apr 26, 3:53 PM CDTMesoscale DiscussionSPCClay97 min
Apr 26, 4:23 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 19 more67 min
Apr 26, 4:44 PM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 11 more5 hr
Apr 26, 5:02 PM CDTSevere Thunderstorm WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lee and 4 more6 hr
Apr 26, 6:10 PM CDTMesoscale DiscussionSPCMississippi95 min
Apr 25, 7:14 PM CDTMesoscale DiscussionSPCAllen, Bourbon, Chautauqua, Cherokee, Crawford, Elk and 5 more91 min
Apr 26, 12:26 PM CDTMesoscale DiscussionSPCBollinger, Butler, Cape Girardeau, Carter, Madison, Mississippi and 6 more94 min
Apr 26, 12:46 PM CDTSevere Thunderstorm WatchSPCBollinger, Butler, Cape Girardeau, Carter, Madison, Perry and 6 more6 hr
Apr 25, 10:30 PM CDTMesoscale DiscussionSPCCherokee, Cleveland, Craig, Creek, Delaware, Garvin and 17 more90 min

Nearby

Mesoscale Discussions in Missouri, 2017Mesoscale Discussions in Arkansas, 2017Mesoscale Discussions in Oklahoma, 2017Every mesoscale discussion in 2017

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.