Severe weather has caused a tree to fall across rail lines in Wellington at 4.40pm.

The Hutt Valley line is currently blocked north of Waterloo station and the tree has also damaged the overhead power and signalling.

KiwiRail crews are working on the blockage and damage, although currently there is no exact time when repairs will be complete and train services between Wellington and Upper Hutt and Masterton can resume.

The blockage only affects trains running through the Hutt valley, services to Paraparaumu and Johnsonville are unaffected by the blockage. Ross Hayward, Rail Passenger Manager at KiwiRail says that bus replacements are not available at short notice during peak time travel.

"We apologise for the disruption this afternoon's weather has caused - while staff are working as quickly as possible to restore services, we cannot get sufficient buses to provide replacements for some time. We hope to restore train services this evening, but ask travellers to be patient in this terrible weather."