He described a funnel descending towards the ground with a small cloud (what he described as a mushroom cloud) at the base of it. He said that it appeared to move in a motion whereby the funnel lent towards him then lent away from him.
After watching the funnel cloud retreat back into the cloud, he said that he noticed spiky bits of cloud hanging down from another dark cloud over Feilding that were rotating, but this ended up fizzing out.
I heard his call five minutes later, at which time I went to my building's stairwell (which has a good view out towards Feilding), to see if I could see it. By this time it had disappeared, but I could see a line of shower clouds running from probably north of Feilding, SE towards Shannon/Levin. This line of shower clouds appered to mark the sea-breeze boundary, as behind them towards the coast, the sky was clear.
My wife, who also works in Feilding said that there had been some thunder and lightning just prior to the time the funnel cloud was spotted.
Roll on summer!!
