Alert archive / Kentucky / Severe Thunderstorm Warnings in 2006

Severe Thunderstorm Warning 438, NWS Louisville, KY

December 1, 2006Grayson County, Hardin County, Kentucky

NWS Louisville, KY issued this severe thunderstorm warning at Dec 1, 2006, 1:07 AM CST for Grayson County, Hardin County, Kentucky. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Dec 1, 2006, 1:07 AM CST (07:07 UTC)
Expired: Dec 1, 2006, 1:30 AM CST
In force: 23 min
Issued by: NWS Louisville, KY
Area: Counties, with a storm outline in the text

Counties Grayson County, KY, Hardin County, KY

The radar

The Louisville radar (KLVX), 48 km from the middle of the area, began a volume at 07:09 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, 7.1 hours before the alert went out and 166 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 108 J/kg
Mixed-layer CIN: -23 J/kg
Mixed-layer LCL: 996 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 265 m²/s²
0-3 km storm-relative helicity: 282 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.5

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Louisville, KY wrote its last area forecast discussion before this severe thunderstorm warning went out at Nov 30, 1:07 PM CST, 12 hours earlier.

Area forecast discussion, Nov 30, 1:07 PM CST, 12 hours before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
307 PM EDT THU NOV 30 2006

.SHORT TERM (TONIGHT AND FRIDAY)...

CURRENTLY...MOSTLY CLOUDY SKIES WERE NOTED ACROSS THE AREA...EXCEPT
FOR A NICE LITTLE CLEAR SPOT ALONG INTERSTATE 65 FROM SDF TO BWG.  A
BIT OF SUNSHINE HAS ALLOWED TEMPS THROUGH THIS NARROW CORRIDOR
ALLOWED TEMPS TO REACH 76 DEGREES (A RECORD) AT BWG AND WE ARE
SITTING AT 70 DEGREES.  FRONTAL BOUNDARY IS LOCATED JUST WEST OF
LOUISVILLE FROM NEAR SCOTTSBURG TO ABOUT HOPKINSVILLE.  BAND OF
SHOWERS HAS FORMED ALONG THE FRONT WITH ALOT OF POST FRONTAL PRECIP
BEHIND.  ACROSS THE EAST...TEMPERATURES ARE WARM AS WELL WITH
READINGS OF 69 AT LEXINGTON AND 70 DOWN AT SOMERSET.

ACTIVE FIRST 24 HOURS OF THE FORECAST PERIOD. 12Z GFS AND NAM-WRF
RUNS ARE COMING INTO BETTER AGREEMENT WITH THE OVERALL EVOLUTION OF
THIS STRONG DYNAMIC STORM SYSTEM.  FRONTAL BOUNDARY TO OUR WEST WILL
REACH A TO ABOUT THE I-65 CORRIDOR THIS EVENING AND THEN STALL OUT
THROUGH THE LATE EVENING.  BOTH THE NAM AND GFS SHOW STRONG SFC LOW
MOVING NORTH FROM EASTERN AR INTO WESTERN IN / EASTERN IL LATE
TONIGHT.  THIS WILL ALLOW THE FRONT TO BACK UP TO THE WEST A BIT
WITH TEMPERATURES WARMING A BIT ACROSS OUR INDIANA COUNTIES.  BOTH
OF THE NCEP MODELS SUGGEST A LINE OF CONVECTION TO DEVELOP OUT JUST
NORTHEAST OF THE SFC LOW TRACKING INTO OUR SW AREA AND THROUGH THE
CENTRAL FA BETWEEN 06 AND 12Z.  OUR LOCAL HIGH REZ WRF SHOWS THE
PRETTY MUCH THE SAME.  SEVERE THREAT WILL BE DAMAGING WINDS.  GIVEN
THE OVERALL INSTABILITY AND HIGH SHEAR COULD SEE QUITE A FEW REPORTS
OF WIND DAMAGE.  ESPECIALLY IN AREAS WHERE WE BOWS/LEWPS IN THE
SEGMENTS.  SOME EMBEDDED SUPERCELL STRUCTURES ARE ALSO
POSSIBLE...BUT THINK THE BEST CHANCE FOR ISOLATED TORNADOES WILL BE
ACROSS OUR SOUTHERN COUNTIES OF THE FA AND FURTHER SOUTH ACROSS WEST
TN.

AS THE LOW LIFTS OFF THE NORTHEAST...COLD AIR WILL SURGE INTO
SOUTHERN INDIANA AND KY. FRONTAL TIMING IS SIMILAR FROM THE 00 AND
06Z RUNS FROM LAST NIGHT.  SHOULD BE IN THE I-65 CORRIDOR AROUND 4-5
AM EST AND EAST OF I-75 BY 12Z.  COLD AIR WILL QUICKLY FOLLOW WITH
ANY POST FRONTAL PRECIPITATION CHANGING FROM RAIN TO SNOW. SHOULD BE
A QUICK TRANSITION BASED ON THERMAL SOUNDINGS.  IN ADDITION...GIVEN
THE TIGHT PRESSURE GRADIENT...MODELS SUGGESTING SUSTAINED WINDS OF
25 TO 35 MPH WITH GUSTS TO 40 MPH.  THEREFORE WILL GO WITH A WIND
ADVISORY FOR FRIDAY IN ALL AREAS.  SNOW SHOWERS WILL CONTINUE
THROUGHOUT THE DAY WITH WINDS BEGINNING TO SLACK OFF BY EVENING.
HIGH TEMPERATURES WILL BE AT 12Z WITH TEMPERATURES FALLING INTO THE
UPPER 20S BY EVENING.  GIVEN THE RELATIVELY WARM GROUND FROM THE
RECENT MILD WEATHER...NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATIONS.  BEST CHANCE OF SEEING MINOR ACCUMULATIONS WOULD
STILL BE ACROSS OUR NORTHERN INDIANA COUNTIES.

-MJ

.LONG TERM FORECAST PERIOD(FRIDAY NIGHT THROUGH THURSDAY)...

ONCE THE STRONG SHORT WAVE EXITS TO THE NORTHEAST AWAY FROM THE
REGION ON FRIDAY NIGHT...THE LONG TERM PERIOD WILL BE CHARACTERIZED
BY A MEAN RIDGE DEVELOPING OVER WESTERN NORTH AMERICA WITH A MEAN
TROUGH OVER THE ERN U.S.  AS THE UPPER RIDGE SHIFTS GRADUALLY TO
THE EAST...THE MEAN 500 MB FLOW WHICH WILL MORE WESTERLY DURING THE
FIRST COUPLE OF DAYS INTO THE PERIOD WILL THEN BECOME MORE
NORTHWESTERLY FOR THE MONDAY THROUGH THURSDAY TIME FRAME AS THE
MEAN RIDGE SHIFTS STEADILY EASTWARD.

A SERIES OF MODEST SHORT WAVES ROTATING AROUND THE MEAN RIDGE INTO
THE MEAN TROUGH WILL BRING SOME REINFORCING BURSTS OF COLD AND DRY
AIR INTO THE REGION. THIS WOULD SERVE TO KEEP THE PRECIPITATION
THREAT MINIMAL AND THE MEAN TEMPS BELOW NORMAL THROUGH THE PERIOD.
HAVE NO REAL PROBLEMS WITH THE FINAL HPC TEMP AND PCPN TRENDS FOR
THIS EXTENDED PERIOD.

TEMPERATURES SHOULD GENERALLY BE SOME 3 TO 10 DEGREES BELOW NORMAL
FOR THIS TIME OF THE YEAR. --21

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&

Hazardous weather outlook, Nov 30, 3:17 PM CST, 9 hours 50 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

Everything else NWS Louisville, KY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 1, 2:00 AM CST	Severe Thunderstorm Warning	LMK	Edmonson, Grayson	30 min
Dec 1, 2:28 AM CST	Severe Thunderstorm Warning	LMK	Hardin	32 min
Dec 1, 3:08 AM CST	Severe Thunderstorm Warning	LMK	Shelby, Spencer	37 min
Dec 1, 3:29 AM CST	Severe Thunderstorm Warning	LMK	Franklin, Henry	31 min
Dec 1, 3:54 AM CST	Severe Thunderstorm Warning	LMK	Boyle, Mercer	21 min
Dec 1, 4:10 AM CST	Severe Thunderstorm Warning	LMK	Fayette, Jessamine, Scott, Woodford	35 min

Nearby

Severe Thunderstorm Warnings in Kentucky, 2006 Every severe thunderstorm warning in 2006

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.