NZ/Aust Weather Comparisons

RWood · Unread post by **RWood** » Thu 25/01/2007 09:38

Another thought about records and observations - it's a great irony that I can't use sensible windrun data for W'gton - apart from new obs. which started only 2 years ago! Trouble is that the Kelburn site (1928-1997) was too close to the ground and severely affected by changes in surrounding vegetation [growth and pruning]. for Wellington of all places, that's truly ironical. There were older records at Thorndon which were probably coherent, but only ran for about 15 years.

On the other hand there is data on maximum daily gust speed - a good proxy for evaluating windiness - for Kelburn dating back to 1967, though only 1972+ is in a database. It's measured on an instrument on a very tall pole so the local obstructions issue doesn't arise. NIWA didn't actually seem to put out reports giving monthly averages of this parameter till I suggested it - just threshold counts of the number days with gusts above 63K and 96K.

RWood · Unread post by **RWood** » Thu 01/02/2007 09:06

janewaystv, can see why you won't be happy with January's results - looks as if drier sunnier conditions have dominated in the east. A contrast to NZ where I expect to see a report of cooler and much cloudier conditions.

Certainly in W'gton we've struggled just to get days at normal temp. levels. To stick my neck out out a bit, I would see this January in NZ as a bit like Jan 1942 - what was that like in Oz? I see a weatherzone forum person reported the driest January ever from somewhere on the mid-NSW coast, surpassing Jan 1942.

janewaystv · Unread post by **janewaystv** » Thu 01/02/2007 12:44

Gday.

Yes, its been a very dry and much sunnier Jan. than usual, rainfall of 45.4mm the lowest since 2003 (13.6mm) and less than half the average.

I suspect that Bondi recorded more rain than than Ob Hill - am yet to get the final total, due to me seeing/hearing some heavy showers at times when Ob Hill recorded none including a fall in the 4th week with 12mm falling in 2 hours.

Sunshine (possibly the sunniest on record at the airport with 290 hours) - final total yet to be confirmed and beating the old record of 288 hrs in 1985).

I would put this month on a par with Jan. 1985.

Following a very dry 1941 (especially during the last 6 months) - contuined into January 1942 (In Sydney's case - the same as Jan. 2003), Melbourne and Brisbane also recorded well below avg. rainfall. Feb. 1942 saw better rainfalls in Brisbane and Melbourne, but not much so in Sydney. March 1942 saw the wettest March ever for Sydney with 521mm falling, giving rise to the expression "It never rains but it definitely pours".

Although 1942 was very dry in Sydney during the 1st 2 months - sunshine hours were quite low with Jan. (201 hrs), Feb. (182 hrs) and March recording only 139 hrs (6th cloudiest on record for a March month).

janewaystv · Unread post by **janewaystv** » Thu 01/02/2007 12:55

Perth has recorded twice its average Jan. rainfall with 19mm, this will seem like a ridiculous notion to you - but bear in mind that the average for Perth is 9mm, so there you are

Hobart (121mm) and Adelaide (40mm) also wetter than average. Brisbane near average with 99mm. Darwin (205mm - avge is 425mm), Canberra (9mm) and Melbourne (32mm) well below average. Sunshine quite plentiful in all areas except the NT and Northern QLD. Coastal Northern QLD recording quite good rains and exceeding the average in some places.

RWood · Unread post by **RWood** » Thu 01/02/2007 15:27

Thanks...Jan 1942 was a month near the end of an El Nino, but the difference from now is that that El Nino had started late in 1939 and stayed at significant levels for almost the entire intervening period.

I don't have a summary report handy for NZ for that month, but the mean NZ temp was about 1.8C below current normals so it was very cool. Not sure about rainfall, except that Central Otago and Fiordland were near normal, In'gill a little wetter, Napier normal and Wellington dryish (54mm). Sunshine was well below normal over a large "middle" swathe of the country, but above average in Northland, Auckland and Bay of Plenty, and near normal in South Canterbury, Otago and Southland.

I don't think Jan 2007 will be a good match for any past one that I can think of...

Perth also a bit cooler than average despite late heatwave, and a bit less sun than its normal (very high) amount for Jan?

janewaystv · Unread post by **janewaystv** » Thu 01/02/2007 18:34

Here is Sydney's Jan. 2007 climate summary.

http://www.bom.gov.au/announcements/med ... 1syd.shtml

janewaystv · Unread post by **janewaystv** » Thu 01/02/2007 18:49

As you can see temps coastal - wise werent that high compared to western suburbs which recorded many hot days with Penrith recording 21 days over 30oC (Im so glad I dont live there

).

Our run of low max/min temps contuined although Jan was above average by a 0.4 degree margin (and being the coolest since 2000 with 24.8oC), min temps didnt fare well either with the difference being only 0.5oC between 2007's total (19.7oC) and the average (19.2oC).

We had 2 days over 30oC on the coast - however they were short-lived with the 38oC one having strong NE winds in the afternoon and 33oC one was followed by a strong S change around midday dropping temperatures to around 21oC by evening.

It certainly was a very windy month here at my place - like December 2006, I dont think I can remember such strong NE winds prevailing into January, humidity was noticeably less here at Bondi, however some humid days were experienced in the city where I work.

Sunshine was the sunniest on record (for the airport that is with 291.4 hrs), Ob Hill's highest Jan. total was 297.6 hrs in 1985.

No storms were recorded - a very disappointing month rain and storm wise.

RWood · Unread post by **RWood** » Thu 01/02/2007 22:04

Very interesting. Just posting NIWA's Jan summary - some surprises for me!

janewaystv · Unread post by **janewaystv** » Thu 01/02/2007 22:49

I'll say. Southland was the only region which was sunnier than normal, wonder why NIWA didnt put out the hours ?

Auckland - sunny with 220 hours compared with the 4 other main centres - mind you I wasnt really surprised as I view the web - cam of Auckland several times per day and it did show quite a lot of sunny days especially during the last 2 weeks.

Temps quite good for Auckland/Hamilton - I suspect the 0.3oC difference between average/2007 of Auckland's temp was due to lower night - time temps ?

Sorry to hear Wellington didnt fare well in all 3 elements during Jan 2007.

Lets hope Feb can bring an improvement

RWood · Unread post by **RWood** » Thu 01/02/2007 23:34

See my notes on the summary [re Nelson etc!!]!

I've looked through some records, and there is no reasonable match for this January, taking just the sun element on its own.

spwill · Unread post by **spwill** » Fri 02/02/2007 08:28

janewaystv wrote,

I suspect the 0.3oC difference between average/2007 of Auckland's temp was due to lower night - time temps ?

We had a cool start to the year.

No storms over Sydney city in Jan is a surprise.
I lived in Sydney from 1990-95, good years for Thunderstorms.

janewaystv · Unread post by **janewaystv** » Sun 22/04/2007 17:47

April 1927.

A small, intense low moved close to the NSW coast generating some phenomenal rain totals between the 16th and 19th.

On the 16th & 17th - Baludelah on the mid-north coast recorded more than 500mm in 24 hours.

Willoughby, a suburb in Sydney's north shore recieved 355mm in 24 hours (18th) which still stands as a local record today. Ob Hill (Sydney City) recorded 124mm during the same period.

Ob Hill recorded a monthly total of 472mm, Wollongong measured 706mm, Brogers Creek (south coast) had 812mm and 600mm fell at Katoomba.

The Nepean/Hawkesbury River system flooded extensively - something we very well wish would happen nowadays.

RWood · Unread post by **RWood** » Sun 22/04/2007 18:00

Only offhand info. I have for NZ for that month indicates a very cool month with average or below average rainfall.

janewaystv · Unread post by **janewaystv** » Wed 02/05/2007 19:24

Seeing that we are forecast to have somewhat a mini heatwave from tomorrow to Saturday with 27oC for tomorrow and 25oC for Friday/Saturday, its a good opporunity to talk about some May records for Sydney (Ob Hill).

May's highest max of 30.0oC was recorded on the 1st 1919 (This is also the only time in May to record a max of 30.0oC+).

The wettest May on record is 1919 with a total of 585mm falling - 94mm fell on the 5th and 114mm on the 26th. The highest 24 hour rainfall of 212.3mm was recorded on the 28th, 1889.

May 1957 is the driest on record with just 3.7mm falling.

May 1942 had a 3 day heatwave with maximums exceeding 27oC and May 1957 had 4 days exceeding 26oC.

May 1942 saw the highest min temp of 20.8oC recorded on the 3rd (The max on this day was 28.3oC).

RWood · Unread post by **RWood** » Wed 02/05/2007 20:23

janewaystv wrote:Seeing that we are forecast to have somewhat a mini heatwave from tomorrow to Saturday with 27oC for tomorrow and 25oC for Friday/Saturday, its a good opporunity to talk about some May records for Sydney (Ob Hill).

May's highest max of 30.0oC was recorded on the 1st 1919 (This is also the only time in May to record a max of 30.0oC+).

The wettest May on record is 1919 with a total of 585mm falling - 94mm fell on the 5th and 114mm on the 26th. The highest 24 hour rainfall of 212.3mm was recorded on the 28th, 1889.

May 1957 is the driest on record with just 3.7mm falling.

May 1942 had a 3 day heatwave with maximums exceeding 27oC and May 1957 had 4 days exceeding 26oC.

May 1942 saw the highest min temp of 20.8oC recorded on the 3rd (The max on this day was 28.3oC).

May 1957 was wet almost everywhere in NZ. May 1942 was Wellington's wettest ever (followed by the driest June on record and a near-record July for rainfall!)

janewaystv · Unread post by **janewaystv** » Wed 02/05/2007 21:21

1942 May - July was totally the reverse for Sydney RWood.

janewaystv · Unread post by **janewaystv** » Thu 03/05/2007 08:07

April 2007 climate summary for Sydney.

http://www.bom.gov.au/climate/current/m ... dney.shtml

It was the wettest April since 2003 (192mm).

Sunshine totalled 207 hours (Last year was sunniest ever Apr with 279 hours). Readings are taken at the airport.

janewaystv · Unread post by **janewaystv** » Thu 03/05/2007 08:10

Climate Summary for Perth April 2007.

http://www.bom.gov.au/climate/current/m ... erth.shtml

Wettest April since 2002 and above average.

RWood · Unread post by **RWood** » Thu 03/05/2007 09:42

Somewhat in contrast with Brisbane, Alice & Darwin...

Manukau heads obs · Thu 03/05/2007 10:15

slow moving weather system/jet streams across australia will mean different area will either be much wetter or much drier than normal
i.e when its raining in one area, it wont be some where else
eventualy the tide will turn and it will be the dry areas turn to get more than normal rain, I would say
note , that the normal, is just the average of the extremes, so in places that get alot of variability, dont expect the normal, expect extremes

RWood · Unread post by **RWood** » Thu 03/05/2007 10:29

Yes, but this sort of thing has gone on too long...

http://www.bom.gov.au/cgi-bin/silo/rain_maps.cgi

janewaystv · Unread post by **janewaystv** » Fri 04/05/2007 18:03

Manukau heads observer wrote:slow moving weather system/jet streams across australia will mean different area will either be much wetter or much drier than normal
i.e when its raining in one area, it wont be some where else
eventualy the tide will turn and it will be the dry areas turn to get more than normal rain, I would say
note , that the normal, is just the average of the extremes, so in places that get alot of variability, dont expect the normal, expect extremes

We do expect extremes but not to the extent of whats been happening since the year 2000 onwards - the length/magnitude of this "drought" has been very severe.

2002 - all state capitals recorded annual rainfall totals in the lowest 10% - 30% of records.

2006 - all bar Darwin recorded annual totals all in the lowest 10% - 20% with Perth and Hobart recording their lowest totals on record.

Rainfall averages have declined significantly over the SE as well as southern WA & SE QLD. A Dam at Brisbane is currently only 19% full and with the onset of the "dry season" it will only get worse unless there is a change in weather patterns to which I dont see happening for this month so far.

There have been some good rainfalls in some parts but they are just not occurring frequently as compared to during the 1980s/1990s.

1895-1902, 1914, 1930s/1940s and 1982/1983 had severe widespread droughts but this one of the 21st century really takes the cake as many records have shown this is by far the severest drought since European settlement around 220 years ago.

Maximum temps have shown rises in successive years especially over SE Australia (NT and SE QLD in some years only, in fact some of the years have been below average), not much of an increase in minimum temps.

Flooding in fact has shown decreases in occurrences as well as severe cyclones.

El Nino is occurring more frequently than La Nina periods (How we very much wish for the La Nina of the 1950s and 1970s/late 80s and early 90s).

So how can all this be normal even allowing for the such variability of our climate ?

janewaystv · Unread post by **janewaystv** » Sun 20/05/2007 16:16

Rwood - in response to your question about rainfall - here is the link to up-to-date rainfall percentages of the monthly mean ending 20th May.

http://www.bom.gov.au/cgi-bin/silo/rain ... ime=latest

Still very poor in all state capitals bar Darwin, getting worse in Queensland, one of the major dams in Brisbane is now at 17%

, with the onset of the "dry" winter season - level 6 water restrictions will come into effect when dams reach the 10% benchmark. I had a mate down here from Brisbane last week, he said it was really bad - everything especially trees are dying in the dozens and in outer suburbs - gardens & parks are resembling that of a mini desert ie all brown and dead, he also said people no longer appreciate the dry & sunny weather nowadays.

We might face possible power rationing/blackouts should rivers contuine to run at low levels. The rain that fell in inland areas were excellent and much needed, however still need much more.

RWood · Unread post by **RWood** » Sun 20/05/2007 17:34

Thanks - yes, it's looking pretty bad for Queensland. One of the retired weather types on the Weatherzone forum claims that good rains will come by mid-June - we'll see.

janewaystv · Unread post by **janewaystv** » Wed 30/05/2007 22:29

RWood - finally here are the stats I promised you.

Data missing in early years - to be expected really & data that was recorded too patchy & not complete.