* WHAT...Snow expected. Visibility one half mile or less at times. Total snow accumulations 10 to 15 inches. * WHERE...Thompson Pass. * WHEN...From 4 AM Friday to 4 AM AKDT Saturday. * IMPACTS...Travel could be difficult. * ADDITIONAL DETAILS...Light snow will develop Thursday evening, then intensify Thursday night into Friday. The heaviest snow is expected during the day Friday. Warming temperatures on Friday will lead to a changeover to rain for lower elevations of the pass. The top of the pass will likely remain all snow. Slow down and use caution while traveling. For the latest road conditions call 5 1 1 or visit 511.alaska.gov.