LHASA, Dec. 29 (Xinhua) -- Southwest China's Tibet Autonomous Region Wednesday issued a red alert, the highest in a four-tier warning system, for snowstorms in some of its southern parts.

Heavy snow will blanket the southern parts of both Xigaze and Shannan cities from now to 11 a.m. Thursday, the regional meteorological bureau said in a statement.

Some of these areas will see snowstorms accompanied by strong gales and sharp temperature drops afterward, it added.

Affected regions should be wary of icy road surfaces. Local governments should take precautions against the possible impact of the snowstorms on water and power facilities and people's lives, the bureau said.

China has a four-tier, color-coded weather warning system, with red representing the most severe alert, followed by orange, yellow, and blue.