On August 25, 2002, at 2045 central daylight time, a Piper PA-34-200T, N9696C, operated by Weather Modification, Inc., collided with the terrain during an overrun landing on runway 08 (3,700 feet by 60 feet, dry asphalt) at the Kenmare Municipal Airport, Kenmare, North Dakota. Neither of the commercial pilots on board were injured. The airplane was substantially damaged. The Title 14 CFR Part 91 business flight was operating in visual meteorological conditions without a flight plan. The flight originated at Stanley, North Dakota, at 1746. The pilot-in-command reported they were conducting a cloud seeding operation during the flight. She stated they ran out of chemical near Kenmare and after contacting her company, they decided to land there. The pilot reported they over flew the runway and noticed the windsock was indicating a wind out of the northeast. The pilot stated the windsock was not straight out and the wind did not seem that strong. She said they then entered the traffic pattern for runway 08 and everything was normal during the approach. She said they made the approach with 2 notches of flaps. As they approached the runway she noticed the airplane was still at 90 knots. The copilot added the remainder of the flaps and the airplane touched down approximately one-quarter the way down the runway. The pilot-in-command stated the airplane would not slow down on the runway even though both she and the copilot were applying the brakes. She stated she then applied full throttle in an attempt to abort the landing; however, it was too late and the airplane traveled off the end of the runway. The airplane skipped over a road and came to rest after skidding sideways in a field. She said that once they exited the airplane, she noticed that the wind had shifted and that there was now a strong wind from the west. The closest aviation weather reporting station is located at Minot, North Dakota, located 37 nautical miles southeast of Kenmare. The winds reported during an observation taken at 2054 were from 110 degrees at 8 knots. The next observation taken at 2154, showed the winds were from 350 degrees at 17 knots gusting to 23 knots.