Ahead of a slow moving upper level disturbance, a band of scattered to broken severe thunderstorms affected central Kentucky and south central Indiana during the evening hours of Sunday 20 April 2003. Due to the slow motion of this upper level low, strong to severe thunderstorms regenerated in the same locations during the evening. Some counties in the Louisville forecast area saw two or more warnings issued for separate thunderstorms. Below are some data relating to these storms, along with a listing of storm reports.
Model Data (for folks with advanced meteorological training):
12hr Eta forecast valid at 8pm EDT 20 April. Notice the band of relatively high surface to 6km shear (lower-right panel), indicating a zone where storms can organize.
18hr Eta forecast valid at 2am EDT 21 April. The band of 6km shear has moved little during the previous 6 hour period, meaning a continued threat of organized convection, assuming all else being equal.
RUC BUFKIT profile valid at 7pm EDT 20 April. Observe the impressive 6km shear and 3km CAPE values.
|Louisville, KY radar showing the onset of severe weather in the area. Note the cell merger over Dubois Co., Indiana (east of Jasper).
|Louisville, KY radar, later in the evening, showing the train of strong to severe storms near the Ohio River. Note the severe storm moving through the Louisville metro area, where it produced 67 MPH straight-line thunderstorm winds at the International Airport. Also, at the end of the loop, an outflow boundary is located from south of Louisville southwestward to near Elizabethtown. Forecasters note these features since they are an important source for thunderstorm regeneration, or they indicate where the low-level air has stabilized.
|Hopkinsville, KY radar showing a right-moving supercell thunderstorm as it crossed a good part of south central Kentucky. This storm during its lifetime produced an F1 tornado over northern Christian County.|
The following is a summary of the local storm reports thus far received by the National Weather Service in Louisville. Should you have a report to offer, please use our online form or feel free to call us at 502-969-8842 during normal business hours.
TIME(EDT) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
0530 PM JASPER IN 1.00 INCH HAIL
0550 PM MORGANTOWN KY .75 INCH HAIL
0600 PM MORGANTOWN KY .75 INCH HAIL
0618 PM ROUNDHILL KY 1.75 INCH HAIL
0635 PM CUB RUN KY .88 INCH HAIL
0715 PM TELL CITY IN 1.75 INCH HAIL
0635 PM HUNTINGBURG IN 69 MPH TSTM WIND GUST
0700 PM SALEM IN .75 INCH HAIL
0724 PM SCOTTSBURG IN .75 INCH HAIL
0754 PM CONCORDIA KY 1.50 INCH HAIL
0805 PM VALLEY CITY IN .88 INCH HAIL
0822 PM CLOVERPORT KY .75 INCH HAIL
0835 PM SHIVELY KY .75 INCH HAIL
0841 PM LOU INT'L AIRPORT KY 67 MPH TSTM WIND GUST
0844 PM LOU BOWMAN AIRPORT KY 55 MPH TSTM WIND GUST
0847 PM EKRON KY 1.75 INCH HAIL
0815 PM CLOVERPORT KY .75 INCH HAIL