The slip near Waiomu was expected to be cleared by 3pm today.
SH25A was also closed due to a slip between Kopu and Hikuai.
The storm first wreaked havoc in Auckland early morning.
Between 8am and 10am rain was recorded at times of 40mm/hour, Dyason said.
Last night the storm continued east and Whakatāne Airport recorded about 24mm an hour around midnight.
The ranges above Gisborne and Hawke's Bay also received a drenching, before the system moved offshore to the east of the country this morning.
Today a showery, westerly flow was moving across the North Island, bringing a moderate risk of thunderstorms to most of the west coast.
"Showers are on the doorstep of Auckland this morning, and it looks like they could get decent in some places later today."
The coast from Northland to Taranaki was right in line for some thunderstorms through the day, with potential for localised heavy rain and small hail.
While the west was in for a wild day of weather, out east was not looking too bad, Dyason said.
Tomorrow a ridge was forecast to move on to the country, before a trough arrived overnight Tuesday and into early Wednesday, spreading across the country Thursday.
On Friday a strengthening moist northwest flow would move over the South Island bringing rain to the West Coast.
Today's weather
Whangārei
Possible early fog. A few showers, some heavy with chance morning thunderstorms. Westerlies. 17C high, 8C overnight.
Auckland
Early fog. Occasional showers, some heavy and possibly thundery in the morning, mainly in the west. Northerlies turning westerly afternoon. 16C high, 10C overnight.
Hamilton
Early fog, then occasional showers, some possibly heavy, easing evening. Northerlies turning westerly afternoon. 15C high, 6C overnight.
Tauranga
Fine spells but chance shower. Northerlies turning westerly afternoon. 16C high, 8C overnight.
New Plymouth Occasional showers, some heavy with possible thunderstorms and hail. Northerlies changing westerly in the morning. 15C high, 8C overnight.
Napier Rain clearing to fine early morning as strong easterlies turn lighter northwest. 18C high, 6C overnight.
Wellington Rain easing to a few showers early morning, possibly heavy from afternoon then clearing evening. Northeasterlies tending northwesterly. 13C high, 10C overnight.
Nelson Showers, some heavy, clearing to fine spells afternoon and northerlies easing. 14C high, 5C overnight.
Christchurch Morning rain then becoming fine. Northeast tending northerly afternoon. 14C high, 4C overnight.
Dunedin Cloudy periods and a few showers both morning and evening. Brisk northeast easing afternoon.
