An "extreme" geomagnetic storm is affecting Earth at present.

Material fired out from a sun spot, is crashing into the planet's atmosphere this weekend .

Transpower says it has put the electricity grid into a 'more' resilient state to protect equipment.

A spokesperson says today's geomagnetically induced currents are below the levels Transpower has been preparing for in its 'worst case scenario' planning.

The spokesperson says the electricity industry held a meeting at 1.30pm today to discuss the effects of and response to the storm.

Transpower says it is still not anticipating having to cut power in any areas, but teams are continuing to monitor the event.

Earlier in the day it issued a grid emergency notice and said it was removing some transmission lines from service across the South Island as a precaution.

The storm has the potential to disrupt power and satellites, as well as communications and GPS.

The US Space Weather Prediction Centre says G5 (extreme) geomagnetic storms can impact power grids, satellites, and radio communications.

The solar storm is expected to peak tonight, with the US Space Weather Prediction Centre forecasting severe conditions from 6-9pm (NZ time) on Saturday.

NIWA says although most solar events do not cause much impact, this is an "unusually strong event" so it pays to be prepared.

It recommends people ensure they have charged batteries and flashlights in case the power goes out.