Summary of flash flooding on June 20 1999:A cluster of thunderstorms developed during the early morning hours of June 20 on the nose of a nocturnal low-level jet. These storms moved very little, and with deep-layer moisture in place to support heavy rainfall rates, these thunderstorms produced very heavy rainfall.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS TSA wrote it up.
Summary of flash flooding on June 20 1999:A cluster of thunderstorms developed during the early morning hours of June 20 on the nose of a nocturnal low-level jet. These storms moved very little, and with deep-layer moisture in place to support heavy rainfall rates, these thunderstorms produced very heavy rainfall. Mayes County was hardest hit, with radar estimating four to seven inches of rain over a large part of the county. One man was killed when his car was washed away by floodwaters flowing over a major highway.The following are some of the heavier rain gage reports for this event: Big Cabin_5NE...7.14", Spavinaw Dam...4.60", Wann...3.74", Claremore_2NE...3.13", Claremore_5W...2.93", Tahlequah_4N...2.81", and Pryor_5NE...2.58", and Centralia_7E...2.25".
The Tulsa radar (KINX), 59 km away, was scanning. The volume nearest the first event began at 09:44 UTC.
5 flash flood. Local standard time, as filed.
There was flooding between OK Hwys 82 and 10 near Blackbird Creek. OK Hwy 82 northwest of Tahlequah was under two feet of water.
Radar estimates of 4 to 8 inches of rain in Mayes County centered near Adair caused major flash flooding. The county emergency manager said in media reports that it was the worst flooding he had seen in his 30 years in that position.Flooding forced the closing of US Hwy 69 2 miles north of Adair and OK Hwy 28 near Adair. Between 630 and 700 AM CDT, a 53-year old man drowned when his car was washed away by eight-foot deep floodwaters flowing over OK Hwy 28 west of Adair. Those floodwaters were associated with heavy flows in a branch of Pryor Creek. Numerous county roads were flooded throughout Mayes County. Pryor Creek jumped its banks near Pryor, displacing ten people from their homes. Two trailers and one home received major damage from Pryor Creek flooding.
Chelsea was particularly hard-hit with flash flooding. Several downtown businesses, especially those on the north side of Main Street (6th Street), had water in their shops. OK Hwy 66 at Pryor Creek was nearly impassable when the creek overflowed onto the road. Otherwise, OK Hwy 28 was flooded 2 miles east of Foyil.
Most small creeks throughout Craig County overflowed their banks, resulting in serious damage to county roads, estimated at $75,000-$100,000. However, no residences were flooded.
County roads were flooded near Nowata.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Flash Flood, Mayes | 1999-06-20 | 53 | Male | Vehicle/Towed Trailer | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oklahoma in 1999Every state in 1999This day in weather historyWarnings in Oklahoma, June 1999
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5700971, 5700972, 5700973, 5701070, 5701071.