Weather officials say residents in areas severely affected by the January 1 Noto Peninsula earthquake should remain vigilant for possible landslides.

The coldest air mass of this season is forecast to flow in from Tuesday onwards, bringing heavy snow to the Sea of Japan coast through Thursday.

In the 24 hours through Tuesday evening, 20 to 40 centimeters of snowfall is expected in areas along the mountains in Niigata Prefecture and the Hokuriku region, 10 to 20 centimeters in low-lying areas of Niigata, and 5 to 10 centimeters in the plains of Ishikawa and other prefectures in Hokuriku.

Snowfall in the 24 hours through Wednesday evening is expected to reach 70 to 100 centimeters in the mountainous areas of Niigata, 30 to 50 centimeters in the low-lying areas of Niigata and Toyama prefectures, and 20 to 40 centimeters in the plains of Ishikawa and Fukui prefectures.

The Japan Meteorological Agency is calling for caution against possible traffic disruptions caused by accumulated snow and icy roads. Officials are also advising residents to be on the alert for avalanches and a phenomenon called snow accretion.

Structures damaged by the quake could topple under the weight of accumulated snow.

Many people have reportedly fallen ill as a result of prolonged stays at emergency shelters. Some have died of possible disaster-related causes.

Evacuees are advised to keep an eye on family members and neighbors who may feel unwell.

The number of jolts in the affected areas has been decreasing, but seismic activity remains at high levels.

As of 4 p.m. on Sunday, 1,484 tremors with an intensity of 1 or higher on the Japanese seismic scale of zero to 7 had been observed since the magnitude 7.6 quake struck on New Year's Day.

Weather officials are urging people to remain alert for upper-5 or stronger quakes for the next two or three weeks.