More than 200 homes in Northland were without power after lightning downed electricity lines and blew transformers.
Northpower linesmen were dispatched to Uretiti, south of Whangarei, after thunder and lightning brought down a power line about 2.15pm yesterday.
Spokesman Steve MacMillan said 78 homes were affected for just over an hour before supplies were restored about 3.25pm.
He said linesmen were also called to work on a transformer at Mt Tiger where 150 people were affected.
Power was back on in an hour and 10 minutes.
In the Far North, five homes were without power after lunch and Top Energy expected supplies to be restored late in the evening.
Isolated thunderstorms over Northland and Auckland yesterday afternoon and evening were expected to produce rainfall of 25 to 35mm per hour.
MetService said rainfall of this intensity could cause flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and that it might also lead to slips and hazardous driving conditions.
Wind gusts of 110km per hour or 60 knots or stronger were predicted.
Showers are predicted for Whangarei, Kerikeri, Kaitaia and Dargaville today, with possible thunderstorms in the afternoon when southerly winds will develop.
Sunday should see showers clearing and the southerlies dying.
Fine weather with light winds were predicted for Monday and Tuesday.
According to rainfall date obtained from the Northland Regional Council, 11.5mm of rain fell at Whangarei Harbour at Marsden Pt from midnight Thursday to 4.03pm yesterday.
Awaroa recorded 19.5mm of rainfall over the same period, Waitangi 14.5mm, Kerikeri 13mm, 12mm Taheke, 9.5mm Mangakahia (Twin Bridges), Kaeo 6.5mm, and Paparoa 5.5mm.