General May Weather

[ricky]

Impressive pressure spike over Auckland earlier today, not sure I've seen anything like this before:

12.55pm - 999.8 hPa
1.00pm - 996.8 hPa
1.05pm - 999.0 hPa

That's a 3 hPa dip over 5 minutes, with no associated rain or wind activity at the time

I had a 1.7 mb hPa dip at 12:34 - 12:39pm, the only thing I can see was the wind swung from NW to W

Had the same thing here in Grey Lynn but did show a brief coincident wind direction change to Northerly

[Cyclone Tracy]

May 2019 stats –

Mean daily temp = 15.4c, 1.4c above normal
Rainfall = 46.0mm (80mm below local average)
Prevailing wind SW
1 thunder day. 31 May
YTD daily mean temp = 19.08c (Around 1.5c above normal)
YTD rainfall = 199.8mm (458mm normal accum to end of May)
Driest start to the year ever recorded (Local records since 2001)

[tornado]

May 2019 stats –

Mean daily temp = 15.4c, 1.4c above normal
Rainfall = 46.0mm (80mm below local average)
Prevailing wind SW
1 thunder day. 31 May
YTD daily mean temp = 19.08c (Around 1.5c above normal)
YTD rainfall = 199.8mm (458mm normal accum to end of May)
Driest start to the year ever recorded (Local records since 2001)

is it odd having thunderstorm in auckland last day of autum?

[NZstorm]

is it odd having thunderstorm in auckland last day of autum?

Its prime time for thunder over the upper North Island. Polar jets are now coming north and there is still some warmth and moisture around.

That thunderstorm last night reached severe limits looking at reported hail size from west Auckland.

https://www.weatherwatch.co.nz/sites/al ... 156104.png

[tornado]

i read that weather watch article as i go on the site often. beautiful lightning show. though. draught for auckland thunderstorm is over.

[David]

Howick stats for May 2019

Mean temp = 14.4C
Mean daily high = 18.7C
Mean daily low = 10.4C
Highest temp = 20.8C (12th)
Lowest temp = 4.6C (1st)
Total rainfall = 85mm
YTD rainfall = 304mm

The mean daily low was 0.1C above April, and overall the month was only 0.6C cooler than April.

[Nev]

MetService May 2019 Summary - An unusually dry month

Highs featured on the weather maps over New Zealand in May, keeping the rain makers away. It was an unusually dry May in the north and east of both Islands, even with the rain right at the end of the month. Many northern and eastern areas of the North Island recorded less than half of normal May rainfall. Abnormally low soil moisture continued across the North Island, especially north of Taupo. This reflects five months of higher than normal pressure over New Zealand, and five relatively dry months in a row.

Whangarei, Pukekohe, Hamilton, Taupo and Napier have all recorded less than 220mm of rain so far in 2019, based on data until the 30th. This is less than 40% of what is normal for Whangarei and about 50% of normal in the other areas.

May started out very cold across the North Island, but temperatures quickly rebounded to run extremely warm across the country for the remainder of the month.

May 2019 Climate Anomaly Maps ℅ NIWA.gif

Some preliminary May 2019 figures for the main centres:

Code: Select all

May 2019 Average Temps, Rainfall, Sunshine and departures from 1981-2010 normals ℅ NIWA

Site                     T-max °C      T-min °C      T-mean °C     Rain mm      Sun hrs

Auckland, Mangere       19.1  +1.6    10.9  +0.5    15.0  +1.0     56   52%    156  109%
Auckland Aero           18.8  +1.4    11.2  +0.6    15.0  +1.0     63   58%
Tauranga Aero           18.7  +1.4     9.7  +0.4    14.2  +0.9     47   43%    n/a  n/a
Hamilton Aero           17.8  +1.0     6.9  +0.5    12.4  +0.8     62   58%
Hamilton, Ruakura       18.1  +1.2     7.8  +0.9    13.0  +1.1     61   63%    129   90%
Wellington, Kelburn     16.3  +2.0    11.2  +2.2    13.7  +2.0     82   74%    169  127%
Christchurch Aero       16.4  +2.1     4.1  +0.4    10.3  +1.3     73  127%    148  106%
Dunedin, Musselburgh    15.6  +2.9     8.0  +2.1    11.8  +2.5     62   95%    109  100%

Edit: Updated MS rainfall data and Chch sunshine.

[RWood]

May 2019 Climate Anomaly Maps ℅ NIWA.gif


Some preliminary May 2019 figures for the main centres:

Code: Select all

May 2019 Average Temps, Rainfall, Sunshine and departures from 1981-2010 normals ℅ NIWA

Site                     T-max °C      T-min °C      T-mean °C     Rain mm      Sun hrs

Auckland, Mangere       19.1  +1.6    10.9  +0.5    15.0  +1.0     56   52%    156  109%
Auckland Aero           18.9  +1.5    11.2  +0.6    15.0  +1.0     47   43%
Tauranga Aero           18.8  +1.5     9.7  +0.4    14.3  +1.0     36   32%    n/a   n/a
Hamilton Aero           17.9  +1.1     6.9  +0.5    12.4  +0.8     55   52%
Hamilton, Ruakura       18.1  +1.2     7.8  +0.9    13.0  +1.1     61   63%    129   90%
Wellington, Kelburn     16.3  +2.0    11.2  +2.2    13.8  +2.1     89   80%    169  127%
Christchurch Aero       16.4  +2.1     4.1  +0.4    10.3  +1.3     59  103%    143* 106%
Dunedin, Musselburgh    15.6  +2.9     8.0  +2.1    11.8  +2.5     62   95%    109  100%
(* missing 1 day's sunshine data)

Do you have the Kelburn sun value for the 31st? Not visible on CliFlo yet. I have 164.4 hours to the 30th (includes a late entry for the 4th). If the monthly total is 169 that is the highest since 171.3 in 1938, and the only other higher value was 172.5 in 1930 (record high).

Edit: 13.8C Tmean for May at Kelburn is a record high, or first equal.

Edit: can see 31st readings now. A quirk of the "daily range" search on CliFlo is in some cases having to choose an end-date beyond the range you want, to make all the data visible.

[Nev]

Edit: 13.8C Tmean for May at Kelburn is a record high, or first equal.

Kelburn's T-mean adjusted to 13.7C, so 2nd-equal May highest (with 2011) after 13.8C in 2016. Its T-min of 11.2C was also 2nd highest after 11.4C in 2016. However, its T-max of 16.3C this May was a record.

Similarly, Musselburgh's T-mean of 11.8C was its 2nd May highest after 11.9C in 1999. Its T-max of 15.6C was also 2nd-equal highest (with 2007) after 16.3C in 1999. However, its T-min of 0.8C 8.0C this May was a record.

Edit: Typo

[RWood]

Edit: 13.8C Tmean for May at Kelburn is a record high, or first equal.

Kelburn's T-mean adjusted to 13.7C, so 2nd-equal May highest (with 2011) after 13.8C in 2016. Its T-min of 11.2C was also 2nd highest after 11.4C in 2016. However, its T-max of 16.3C this May was a record.

Similarly, Musselburgh's T-mean of 11.8C was its 2nd May highest after 11.9C in 1999. Its T-max of 15.6C was also 2nd-equal highest (with 2007) after 16.3C in 1999. However, its T-min of 0.8C this May was a record.

A close thing though for Kelburn's Tmean - averaging the daily numbers gives a value just a whisker below 13.75C, while 2016's value is about 13.76C.