On March 4, 1998, at 0907 eastern standard time, a Cessna 650, N502T, operated by Tenneco Management Company, experienced a nose gear collapse during an overrun landing on runway 09 (5,502' x 100') at the Manistee County - Blacker Airport, Manistee, Michigan. The 14 CFR Part 91 corporate flight was operating in instrument meteorological conditions on an IFR flight plan. The captain, co-pilot, and seven passengers on board were not injured. The airplane was substantially damaged. The flight originated from Waukegan, Illinois, at 0737 central standard time. The pilot-in-command (PIC), who was flying the airplane, reported they flew the VOR approach to runway 09. He reported that the lack of contrast due to the snow covered terrain distorted their "depth perception and other visual cues" when transitioning from instruments to visual for landing. The PIC reported that the airplane "floated" during the landing flare. He reported that the airplane traveled off the end of the runway even though they used the spoilers, speed brakes, maximum reverse, and maximum braking. The co-pilot reported they received the Automated Weather Observing System (AWOS) report from Manistee approximately 10 minutes prior to arrival. He reported the "Weather was above required minimums on all reports obtained." He also reported that Manistee UNICOM informed them that there was approximately 1/2 inch of snow on the runway and braking action was fair to poor. He reported that they were cleared for the approach and the airplane was in VFR conditions with "clear ground (water over Lake Michigan) contact with a haze layer visible inland in the approximate location of the airport." He continued to report that the runway lights were visible at a point 2 miles from the airport. The co-pilot reported, as the pilot-in-command did, that the ground was snow covered which provided "no visual contrast to aid depth perception and the departure end of the runway was not discernible...." He reported the airplane floated during the landing which resulted in a touchdown point further down the runway then what they desired. The Manistee County - Blacker Airport manager reported the runway lights were on high with the REILS and VASI on at the time of the accident. He reported "When aircraft came by office it was high (above normal touchdown) and was out of sight when it touched down." He estimated the visibility was about one mile at the time of the accident. He drove in his vehicle down the runway and from the tracks on the snow covered runway, he estimated that N502T touched down 3,100 to 3,200 feet down the runway. Photographs taken by the airport manager after the accident show the terrain was snow covered with grass visible through the snow adjacent to the runway. The airplane came to rest approximately 120 feet off the departure end of runway 09. The nose gear collapsed and punctured the pressure bulkhead when the airplane contacted soft terrain off the end of the runway. A cassette copy of the cockpit voice recorder tape was provided to the National Transportation Safety Board by the Tenneco Management Company. According to Tenneco procedures, the non- flying pilot, in this case the co-pilot, would be calling out checklist items on the Landing Preliminary checklist. The co-pilot received the AWOS weather just prior to being cleared to 3,000 feet by air traffic control. He briefed the PIC that the winds were being reported as "350 at 8." He then stated "now instead of two scattered it's partially obscured and two broken." Several comments followed regarding the decreased visibility just past the shoreline. The co-pilot commented "maybe we can see better than we think when we get in there." He then remarked, "well I'll tell you what she's gonna be tight...." This remark was followed by the 500 foot altitude call-out from the Ground Proximity Warning System (GPWS). Approximately twenty-one seconds later the co-pilot stated "I got the runway lights." This is followed by the GPWS call-out "minimum, minimum." He then stated "still have runway lights, approach lights." The GPWS call-out "sink rate, two hundred" was heard followed by the PIC calling for "final flaps" and the co-pilot saying "ok there's the runway." This was followed by two more "sink rate" call-outs then the sound of the airplane touching down. One of the pilots returned to the cockpit approximately five minutes after the accident to call for a vehicle and to cancel their flight plan. As he was switching radio frequencies the Manistee AWOS can be heard over the radio. The AWOS at that time was reporting "partially obscured ceiling 100 broken." The VOR/GPS RWY 9 approach minimum descent altitude for a Category C airplane with DME is 441 feet. Weather minimums for the approach are 500 foot ceiling and 1 1/4 mile visibility. A review of the flight data recorder printout provided by Tenneco Management Company shows the airplane touched down at an indicated airspeed of about 138 knots. The cockpit voice recorder revealed the co-pilot called out a Vref during the "Landing Preliminary" checklist of "32."