Special Climate Topics

November 30, 1996 Winter Storm

The Effects of Snow Cover on Temperature

A winter storm can play havoc with weather for days. Even if the sun shines afterwards, areas with snow on the ground just cannot warm up as much as neighboring areas without snow. Much of the solar radiation bounces back into space off highly reflective snow surfaces, and the energy that is absorbed by the surface is used to melt the snow before increasing the air temperature.

Here is a recent example. On Saturday, November 30, a winter storm produced a narrow band of heavy snow from the Texas panhandle, into northwest Oklahoma and southern Kansas. The National Weather Service Office in Norman issued special weather statements mentioning the upcoming storm beginning Wednesday and on Friday morning issued a Winter Storm Watch for Saturday for northern and western Oklahoma northwest of a Hollis to Watonga to Stillwater line. On Friday evening, a Winter Storm Warning was issued for northwest Oklahoma.

An area of northwest Oklahoma received 4 to 6 inches with a small area to the northwest of Woodward, Oklahoma receiving 8 to 10 inches of snow. The winter storm quickly exited the southern plains, and skies were sunny the next day.

Map 1. Snowfall reports in inches on 11/30/96

The satellite picture Sunday morning showed the areas with snow on the ground. This area is shown between the light blue lines on the map below. Under sunny skies on Sunday, the snow melted in the areas where the snow was not too deep. Late Sunday afternoon, the satellite showed that the areas within the dark blue lines on the map still had snow on the ground. The afternoon satellite picture is shown below.

Map 2. Satellite picture showing snow cover on December 1 at 4:15 p.m. CST

Map 3. Area with snow on the ground on the morning (between the light blue lines) and in the afternoon (between the dark blue lines), and high temperatures (in red) on December 1.

The red numbers on the map show the high temperatures on Sunday, December 1 from NWS and FAA observation locations and the Oklahoma mesonet. The areas that had snow on the ground struggled to reach high temperatures in the upper 30s and lower 40s, while areas without snow climbed into the 50s. Notice to the west and northwest of Weatherford, Oklahoma. The mesonet station near the town of Putnam only reached 39 degrees, while just 27 miles to the southwest, the mesonet station near Butler, Oklahoma climbed to 52 degrees.

Oklahoma mesonet data courtesy of the Oklahoma Mesonet and the Oklahoma Climatological Survey.