Alert archive / Illinois / Mesoscale Discussions in 2016

Mesoscale Discussion 577

May 9, 20168 counties in Illinois; 5 counties in Kentucky; 7 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 9, 2016, 9:42 PM CDT for 8 counties in Illinois; 5 counties in Kentucky; 7 counties in Missouri. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
May 9, 2016, 9:42 PM CDT (02:42 UTC)
Expired
May 9, 2016, 11:15 PM CDT
In force
93 min
Issued by
the Storm Prediction Center

Counties Alexander County, IL, Hardin County, IL, Johnson County, IL, Massac County, IL, Pope County, IL, Pulaski County, IL, Union County, IL, Williamson County, IL, Ballard County, KY, Carlisle County, KY, Graves County, KY, Hickman County, KY, McCracken County, KY, Bollinger County, MO, Cape Girardeau County, MO, Mississippi County, MO, New Madrid County, MO, Perry County, MO, Scott County, MO, Stoddard County, MO

The radar

The Paducah radar (KPAH), 66 km from the middle of the area, began a volume at 02:41 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

Little Rock, AR (KBYH), launched 00:00Z, 2.7 hours before the alert went out and 260 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, Little Rock, AR at 00:00Z on 2016-05-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 606 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, Little Rock, AR at 00:00Z on 2016-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 289 square meters per square second.1939587897117Sfc1 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
606 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
834 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
289 m²/s²
0-3 km storm-relative helicity
399 m²/s²
Significant tornado parameter
1.1
Supercell composite
15.6

Open this sounding in Storm Lab

The text

As transmitted.

355 
ACUS11 KWNS 100243
SWOMCD
SPC MCD 100242 
KYZ000-ILZ000-MOZ000-100415-

MESOSCALE DISCUSSION 0577
NWS STORM PREDICTION CENTER NORMAN OK
0942 PM CDT MON MAY 09 2016

AREAS AFFECTED...SOUTHEAST MO TO SOUTHERN IL/WESTERN KY

CONCERNING...SEVERE THUNDERSTORM WATCH 158...

VALID 100242Z - 100415Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 158
CONTINUES.

SUMMARY...ISOLATED WIND DAMAGE WILL CONTINUE AS A SQUALL LINE/BOW
ECHO CONTINUES NORTHEASTWARD ACROSS FAR SOUTHEAST MO INTO FAR
SOUTHERN IL AND WESTERN KY THROUGH LATE EVENING.

DISCUSSION...A BOWING SQUALL LINE WILL CONTINUE TO MOVE
NORTHEASTWARD AT 50+ MPH ACROSS FAR SOUTHEAST MO INTO FAR SOUTHERN
IL AND WESTERN KY THROUGH LATE EVENING. LINE-RELATIVE CONVERGENCE
CONTINUES TO INCREASE AS WEAK PRESSURE FALLS OCCUR WITH BACKING
LOW-LEVEL WINDS...ALTHOUGH THE SQUALL LINE SHOULD EVENTUALLY INGEST
SOMEWHAT COOLER/MORE STABLE INFLOW AS IT PROGRESSES INTO SOUTHERN
IL/WESTERN KY. NONETHELESS...ISOLATED WIND DAMAGE WILL REMAIN A
POSSIBILITY OVER THE NEXT COUPLE OF HOURS PARTICULARLY GIVEN THE
FAST /50+ MPH/ FORWARD MOTION AND ORGANIZATION OF THE MCS.

..GUYER.. 05/10/2016

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

ATTN...WFO...PAH...MEG...LSX...

LAT...LON   36559034 37109040 37728999 37778871 37678815 36618866
            36559034

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 9, 8:16 PM CDTSevere Thunderstorm WatchSPCAlexander, Gallatin, Hardin, Jackson, Johnson, Massac and 5 more6 hr
May 10, 7:01 AM CDTMesoscale DiscussionSPCFranklin, Gallatin, Hamilton, Jackson, Jefferson, Monroe and 9 more104 min
May 10, 12:59 PM CDTSevere Thunderstorm WatchSPCAlexander, Hardin, Johnson, Massac, Pope, Pulaski and 1 more9 hr
May 10, 3:08 PM CDTMesoscale DiscussionSPCAlexander, Massac, Pulaski67 min
May 10, 5:06 PM CDTTornado WatchSPCGallatin, Hardin, Massac, Pope, Saline6 hr
May 10, 12:38 PM CDTMesoscale DiscussionSPCAnderson, Bath, Boone, Bourbon, Boyle, Bracken and 50 more67 min
May 10, 3:44 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Boone, Bourbon and 49 more61 min
May 10, 5:19 PM CDTMesoscale DiscussionSPCBoyd, Breathitt, Carter, Clay, Elliott, Estill and 23 more86 min
May 10, 5:52 PM CDTSevere Thunderstorm WatchSPCBath, Bell, Boyd, Breathitt, Carter, Clay and 31 more7 hr
May 9, 7:23 PM CDTTornado WatchSPCDunklin, Pemiscot8 hr
May 9, 7:33 PM CDTMesoscale DiscussionSPCAtchison, Holt57 min
May 9, 10:06 PM CDTMesoscale DiscussionSPCAtchison, Holt, Nodaway54 min
May 9, 10:37 PM CDTMesoscale DiscussionSPCBarry, Barton, Cedar, Christian, Dade, Dallas and 10 more83 min

Nearby

Mesoscale Discussions in Illinois, 2016Mesoscale Discussions in Missouri, 2016Mesoscale Discussions in Kentucky, 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.