Debris avalanches and debris flows warning yellow level for store deler av Østlandet

2

Yellow level

Published: Valid: from 03.10.2021 07:00 to 04.10.2021 06:59
Next forecast before:
  • Danger increase: Sunday, October 3, 2021, kl. 7:00 AM
  • Danger decrease: Monday, October 4, 2021, kl. 6:00 AM
  • Height: 0 - 2500 moh

Consequence

Some landslides are expected. A few large slides may occur. Exposed railways and roads may be closed. Debris avalanches/shallow slides are soil slides and rapid movement of saturated soil in steep terrain. Debris flows are a "flood" of water, soil and rocks in steep creeks. Surface runoff in steep terrain can cause streams to change regular flow patterns. Along the watercourses in the flood areas high discharge can lead to erosion of masses at the foot of slopes. Rapid decline of water levels after flood can also cause local landslides. Debris flows may reach the valley bottom even if they are triggered high in the terrain.

Advice

Keep yourself updated about the development of the weather, the landslide and flood situation, and follow the weather radar. Keep away from steep slopes, as well as streams and rivers with high discharge. Keep water paths and culverts free of snow, ice, gravel, waste, twigs and leaves. Clogged waterways with dammed water may cause landslides. River erosion may trigger minor soil slips, which again may reduce the soil stability along the river. Be aware of such soil slips in areas mapped with quick clay, and areas with marine deposits. If such observations are made, do not hesitate to alert responsible municipal emergency staff at the local kommune.

Description

Some landslides are expected. A few large slides may occur. Exposed railways and roads may be closed. Steep slopes, as well as streams and rivers with high discharge, are particularly exposed. Heavy rain is expected.