SEA91FA061

The acft was 1 of 5 that were on a return trip from los angeles, CA, to abbotsford, british columbia, Canada. The flt crews had obtained wx info during stops at cresent city, CA, & newport, OR. After lndg at everett, WA, one of the flt crews filed a flt plan for all 5 acft. At that time, he was asked if he wanted a wx briefing, but he indcd they had already rcvd a brief for the route. Rprtdly, the plts also obtained wx info from a computer in the lobby of an FBO at everett. After depg everett on a ngt flt to abbotsford, the flts enctrd deteriorating wx with snow & clouds. The flt crews of 2 acft reversed course & lndd at an alternate arpt. The crew of a 3rd acft diverted, went over water, then contd en route. However, the 2 remaining acft (c-gjnm & c-gixi) collided with mountainous trrn abt 3 mi apart. C-gjnm impacted on wooded trrn at an elev of abt 2100'. Abt 11 mi nw at Bellingham, WA (elev 158'), the 1950 wx was in part: 2100' bkn, 10 mi vis with rain, wind fm 240 deg at 6 KTS. The wreckage was fnd the next day cvrd with snow.