Well south of a frontal boundary, a moist and unstable air mass resided over the Ohio Valley.  The ground was already wetter than normal from previous rains.  A southwest and west wind along with daytime heating formed showers and thunderstorms during the afternoon of the 20th.   Overnight, more storms formed along a leftover east to west boundary.  That allowed for repetitive showers from portions of northeast Kentucky into extreme southern Ohio and western West Virginia.
The main period of rain was from around 1400E on the 20th to 0100E on the 21st.  In northeast Kentucky, the highest rain totals were in western and southern portions of Carter County.  The cooperative observer at Grayson Lake had 6.21 inches in the 24 hours ending on the morning of the 21st.  Olive Hill measured 5.57 inches.  Nearby, the automatic gauge at Globe had 5.2 inches.  The cooperative observer at Grayson measured 3.37 inches.  In Greenup County, Warnock had 2.45 inches but amounts increased toward the Ohio River.  The city of Greenup measured 3.27 inches and the Greenup Lock and Dam had 2.96 inches.

Flood in GREENUP, KENTUCKY
From 21-JUL-10 04:45:00 to 21-JUL-10 22:45:00 (EST-5)
Location: SOUTH SHORE
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

High water lingered on the larger streams and the Little Sandy River, but with little damage.  The crest on the lower portion of Tygart Creek was 19.9 feet compared to 24.4 feet back in the May 2010 flood.

Flash Flood in BOYD, KENTUCKY
From 21-JUL-10 01:15:00 to 21-JUL-10 04:15:00 (EST-5)
Location: SUMMIT
Flood cause: Heavy Rain
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Overflowing streams blocked roads, including portions of Route 5.  However, damage to dwellings was minimal.

Flash Flood in CARTER, KENTUCKY
From 20-JUL-10 20:15:00 to 21-JUL-10 04:45:00 (EST-5)
Location: SOLDIER
Flood cause: Heavy Rain
Property damage: 5.00M
Crop damage: 0.00K
Reported by: Emergency Manager

Streams such as Tygart Creek, Little and Big Sinking Creeks, Henderson Branch, Smith Run, and Mills Branch saw major flash flooding.  A 72 year old woman drowned.  Her mobile home was washed off its foundation and pushed some 200 yards to a bridge.  The home broke into pieces at the bridge.  Her body was not found until 3 days later near the mouth of the creek with the Little Sandy River.   Downtown Olive Hill was flooded again.  The crest was about a foot in downtown, compared to 4 to 5 feet during the flood in May.  Nineteen homes were destroyed in the county with major damage to 60 to 70 others.  Most of the damage was concentrated in the Grahn and Fultz vicinity.  Around a half dozen vehicles were washed into Little Sinking Creek.   Several private and a few public bridges were destroyed.
Governor Steve Beshear declared a state of emergency.  Carter County was included in the FEMA disaster declaration number 1925.

Flood in CARTER, KENTUCKY
From 21-JUL-10 04:45:00 to 21-JUL-10 21:45:00 (EST-5)
Location: OLIVE HILL
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Emergency Manager

After a night of flash flooding, the larger streams and the Little Sandy River were still flooding across roads and fields.  The crest at Grayson on the Little Sandy River was near 25 feet during the late afternoon on the 21st.   Flood stage is 21 feet.  Damage was minor compared to the earlier flash flooding.

Flash Flood in GREENUP, KENTUCKY
From 20-JUL-10 21:55:00 to 21-JUL-10 04:45:00 (EST-5)
Location: SOUTH SHORE
Flood cause: Heavy Rain
Property damage: 300.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Since the heaviest rains fell over the northern portions of the county, most of the stream and street flooding was concentrated near the Ohio River communities.   Several roads were closed in Worthington and Greenup. There was a water rescue in Lloyd.