April sun in Gisborne

A109 Light Utility Helicopter flight with mayor Gisborne City from the air in November 2023.

Despite recent rain, the area around Gisborne remains in soil moisture deficit and follows one of the driest Aprils in the past 115 years.

Climate records held by the National Institute of Water and Atmospheric Research (Niwa) show it was the sixth driest April since weather data started being recorded here in 1905.

The recent front that passed through delivered the heaviest falls to the top end of the district, with up to 200 millimetres in the Tapuaeroa Valley, below Mount Hikurangi.

But only small amounts were delivered in Gisborne and surrounding hills, with Wharekopae getting the largest fall of just over 30mm.

Over April just 32mm of rain fell — two-thirds of the month's 30-year average of 98mm.

The last dry April was in 1989 — 20mm. April of 1986 received 13mm.

The driest April on record was in 1958, a mere 8.5mm, 1945 got 10mm and 1915 had 21.6mm.

For the year to date, the rainfall total is over 120mm down on the same time last year.

Niwa's daily climate maps show the impact of the low rainfall.

The district is close to joining a large part of the North Island now described as extremely dry.

Gisborne's soil moisture deficit at the end of April was over 102mm, with the driest area the Flats and surrounding hill country.

According to the Niwa website, If the SMD is between 110mm and 130mm, then the soil is “severely dry”. If the SMD is less than 130 mm, then the soil is “extremely dry”.

The Waioeka-Motu-Matawai area is the only place where local rainfall has been anywhere near normal.

Experiencing the Covid 19 shutdown was made easier for Gisborne residents by a month of warmer-than-usual temperatures, an increase in warm north-west winds, clearer skies and more sun.

Daytime temperatures hit an average of just over 20.6 degrees — 0.7 of a degree warmer than the 30-year mean.

Despite some chilly mornings, minimum temperatures were still half a degree warmer than usual at 10.2 degrees.

The first real frost struck on the 15th with a grass minimum of minus-1.3 degrees, and that was followed by the last five days of the month all in the chill zone, with a zero grass minimum on the 30th.

Only three nights had temperatures staying above the 10-degree mark, but a summery 17.8 minimum on the 17th was a surprise.

Clear skies meant April totalled almost 190 hours of sunshine — 25 hours more than the 30-year average.

Niwa says the district has been enjoying 115 percent of normal sun. In terms of a daily dose, that is about an hour a day more — six to seven hours, rather than five to six.

The latest Niwa outlook for the three months to the end of July suggests little change to the current conditions.

For the Gisborne district, this is Niwa's latest set of probabilities —

Temperatures are about equally likely to be near average (a 40 percent chance) or above average (45 percent).

Rainfall totals are about equally likely to be near normal (a 35 percent chance) or below normal (40 percent).

Soil moisture levels and river flows are equally likely to be near normal (a 40 percent chance) or below normal (40 percent).