Alert archive / Missouri / Mesoscale Discussions in 2017

Mesoscale Discussion 218

February 28, 20175 states

The Storm Prediction Center issued this mesoscale discussion at Feb 28, 2017, 1:46 PM CST for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Feb 28, 2017, 1:46 PM CST (19:46 UTC)
Expired
Feb 28, 2017, 4:15 PM CST
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 109 counties

Baxter County, AR, Benton County, AR, Boone County, AR, Carroll County, AR, Clay County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Cross County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Garland County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Johnson County, AR, Lawrence County, AR, Logan County, AR, Lonoke County, AR, Madison County, AR, Marion County, AR, Mississippi County, AR, Monroe County, AR, Newton County, AR, Perry County, AR, Poinsett County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Randolph County, AR, Saline County, AR, Searcy County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, Van Buren County, AR, Washington County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Alexander County, IL, Franklin County, IL, Jackson County, IL, Jefferson County, IL, Johnson County, IL, Massac County, IL, Monroe County, IL, Perry County, IL, Pulaski County, IL, Randolph County, IL, Saint Clair County, IL, Union County, IL, Washington County, IL, Williamson County, IL, Ballard County, KY, Carlisle County, KY, Fulton County, KY, McCracken County, KY, Barry County, MO, Bollinger County, MO, Butler County, MO, Camden County, MO, Cape Girardeau County, MO, Carter County, MO, Christian County, MO, City of Saint Louis, MO, Crawford County, MO, Dallas County, MO, Dent County, MO, Douglas County, MO, Dunklin County, MO, Franklin County, MO, Greene County, MO, Howell County, MO, Iron County, MO, Jefferson County, MO, Laclede County, MO, Lawrence County, MO, Madison County, MO, Maries County, MO, McDonald County, MO, Mississippi County, MO, New Madrid County, MO, Oregon County, MO, Ozark County, MO, Pemiscot County, MO, Perry County, MO, Phelps County, MO, Polk County, MO, Pulaski County, MO, Reynolds County, MO, Ripley County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Scott County, MO, Shannon County, MO, Stoddard County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Washington County, MO, Wayne County, MO, Webster County, MO, Wright County, MO, Lake County, TN

The radar

The Little Rock radar (KLZK), 184 km from the middle of the area, began a volume at 19:46 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 12:00Z, 7.8 hours before the alert went out and 213 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 12:00Z on 2017-02-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 573 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 12:00Z on 2017-02-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 370 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
573 J/kg
Mixed-layer CIN
-124 J/kg
Mixed-layer LCL
708 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
370 m²/s²
0-3 km storm-relative helicity
379 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.9

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
Feb 28, 2:10 AM CSTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Chicot, Desha, Drew and 2 more3 hr
Feb 28, 3:40 PM CSTTornado WatchSPCArkansas, Baxter, Benton, Boone, Carroll, Clark and 50 more6 hr
Feb 28, 5:28 PM CSTMesoscale DiscussionSPCBaxter, Boone, Clay, Cleburne, Conway, Craighead and 36 more2 hr
Feb 28, 2:03 PM CSTMesoscale DiscussionSPCBureau, DeKalb, DuPage, Ford, Fulton, Grundy and 24 more2 hr
Feb 28, 2:19 PM CSTTornado WatchSPCAlexander, Bond, Calhoun, Clinton, Edwards, Fayette and 27 more7 hr
Feb 28, 2:57 PM CSTTornado WatchSPCAdams, Boone, Brown, Bureau, Carroll, Cass and 63 more7 hr
Feb 28, 5:24 PM CSTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 28 more96 min

Nearby

Mesoscale Discussions in Missouri, 2017Mesoscale Discussions in Arkansas, 2017Mesoscale Discussions in Illinois, 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.