Alert archive / Kentucky / Mesoscale Discussions in 2014

Mesoscale Discussion 113

February 18, 201424 counties in Kentucky; 22 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Feb 18, 2014, 10:06 PM CST for 24 counties in Kentucky; 22 counties in Tennessee. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Feb 18, 2014, 10:06 PM CST (04:06 UTC)
Expired
Feb 19, 2014, 12:30 AM CST
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
5%
All 46 counties

Allen County, KY, Barren County, KY, Butler County, KY, Caldwell County, KY, Calloway County, KY, Christian County, KY, Edmonson County, KY, Graves County, KY, Grayson County, KY, Green County, KY, Hart County, KY, Hopkins County, KY, Logan County, KY, Lyon County, KY, Marshall County, KY, McLean County, KY, Metcalfe County, KY, Monroe County, KY, Muhlenberg County, KY, Ohio County, KY, Simpson County, KY, Todd County, KY, Trigg County, KY, Warren County, KY, Benton County, TN, Carroll County, TN, Cheatham County, TN, Clay County, TN, Davidson County, TN, Dickson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Jackson County, TN, Macon County, TN, Montgomery County, TN, Robertson County, TN, Rutherford County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Weakley County, TN, Williamson County, TN, Wilson County, TN

The radar

The Ft Campbell radar (KHPX), 10 km from the middle of the area, began a volume at 04:08 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

Nashville Metro, TN (KBNA), launched 00:00Z, 4.1 hours before the alert went out and 82 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, Nashville Metro, TN at 00:00Z on 2014-02-19Temperature 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, Nashville Metro, TN at 00:00Z on 2014-02-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 290 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
2116 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
290 m²/s²
0-3 km storm-relative helicity
294 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

916 
ACUS11 KWNS 190406
SWOMCD
SPC MCD 190406 
KYZ000-TNZ000-ILZ000-190630-

MESOSCALE DISCUSSION 0113
NWS STORM PREDICTION CENTER NORMAN OK
1006 PM CST TUE FEB 18 2014

AREAS AFFECTED...WRN KY THROUGH

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 190406Z - 190630Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND
SPREAD EWD THROUGH WRN AND CNTRL KY AND PARTS OF WRN AND MIDDLE TN.
SOME OF THE STORMS MAY EVENTUALLY BECOME CAPABLE OF ISOLATED
MARGINALLY SEVERE HAIL. SEVERE THREAT IS NOT EXPECTED TO BECOME
SUFFICIENT FOR A WW.

DISCUSSION...LATE THIS EVENING SCATTERED ELEVATED CONVECTION IS
DEVELOPING OVER WRN KY. ACTIVITY IS INITIATING WITHIN ZONE OF
DESTABILIZATION AND ASCENT FORCED BY A PROGRESSIVE SHORTWAVE TROUGH
LOCATED OVER THE MS VALLEY REGION AND ITS ATTENDANT 40 KT SWLY LLJ.
A CORRIDOR OF MODEST INSTABILITY /800-1000 J/KG/ MUCAPE HAS
DEVELOPED OVER WRN AND MIDDLE TN INTO SWRN KY WHERE THE LLJ HAS
ADVECTED RICHER MOISTURE BENEATH STEEP MIDDLE LEVEL-LAPSE RATES BUT
ABOVE THE STABLE SURFACE LAYER. THE ATMOSPHERE APPEARS MORE CAPPED
WITH SWRN EXTENT INTO WRN AND MIDDLE TN...SO SRN EXTENT OF THE MORE
ROBUST THUNDERSTORM DEVELOPMENT IS UNCERTAIN. HOWEVER...GLAZING
INFLUENCE OF ASCENT ALONG SRN PERIPHERY OF THE SHORTWAVE TROUGH MAY
BE SUFFICIENT TO ERODE THE CAP AND INITIATE STORMS INTO NRN PARTS OF
WRN AND MIDDLE TN. THREAT SHOULD REMAIN RESTRICTED TO ISOLATED HAIL
GIVEN THE ELEVATED NATURE OF THE DEVELOPING STORMS.

..DIAL/HART.. 02/19/2014

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

ATTN...WFO...LMK...OHX...PAH...MEG...

LAT...LON   37428787 37748607 37258535 36558547 35928612 35578724
            35818826 36298886 36978880 37428787

Nearby

Mesoscale Discussions in Kentucky, 2014Mesoscale Discussions in Tennessee, 2014Every mesoscale discussion in 2014

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.