J07

With a high over the country, there would always be an inversion at the top of the boundary layer.

Yeah, that was a real beauty up there yesterday! There was a severe thunderstorm warning issued for those. There's been some very humid air hanging around, which has made conditions more like February up in Northland. Day after day they've been getting highs of mid to high 20s, with dewpoints of 19C-21C. Despite all that, most places barely got any rain. But those that got it...really got it. Mean 24 hour temperatures in Whangarei since last Sunday: 21C; 22C; 23C; 22C; 21C; 19C. Today will be much fresher. Pretty terrible start to the summer for eastern areas though. Cold, grey and miserable in Wellington for far too many days.

Thing is, the Beaufort Scale is supposed to be referring to mean speeds. You may have had gusts of 130 mph a few years back, but mean speeds of 130 mph are quite something else.

Looking at that chart you would almost think "write off" for the entire month. But I remember a decent dumping of snow in Bristol at the end of Feb 2004. Probably they haven't had one like it until Feb 2009!

Highest temperature this month will turn out to be the 32C in Whakatane (new November record) and Kawerau (not a November record). Today a weakening trough is moving north, followed by a dramatic change to recent weeks with the southerly behind it. Temperatures in the south island more like mid teens rather than mid-high 20s. I am quite happy to get some rain here, but it's rather too cold for the tomatoes....

Two places hit 32C today, and dewpoints were also high in those locations (around 18C). A warm and humid day for pretty much everyone, except east coast of the South Island where temperatures inland were in the low 20s and dewpoints below zero. There also were severe thunderstorms this afternoon, with a very high tropopause (14km apparently).

Eh, a funny old day. Kaikoura reached 29C at 1AM, then plummeted to 16C in a gale force southerly. For proper daytime highs, 32C has been reached in the Bay of Plenty, and with dewpoints of around 18C up there it would feel pretty humid. It's certainly warm for November!

Todays highs were 31C at Alexandra and Dunedin Airport. This is the warmest day since February. The cold front at 9PM was clearly between Timaru and Christchurch. Still 24C at Le Bons Bay (9PM), but that should drop quickly as the front goes through.

What a soul destroying response.

I should have saved the surface chart for this event, but from memory it looks very similar to what has hit the UK in recent days with a strong, warm and very moist flow benefiting from orographic lift. They also happened at pretty much the same time of year (SSTs relatively high).

It was an interesting event, it is not too common in winter for one of those roads (Napier-Taupo Highway, which reaches about 800m) to get such heavy snow. So in October, very unusual. Good to see a typical kiwi in there at the end, digging in the snow whilst wearing very short shorts.

Today, 3 locations reached 30C. Of those, the most interesting was probably Oamaru, which reached 24C at 6AM, rose to 30C early afternoon, then in 30 mins fell to 12C with a southwest change.

Well done Nick. Further Maths is an excellent choice. I was one of 3 people in a sixth form of ~200 who took it. I always thought everyone else was missing out! (And still do!)

The warm water has got quite a long way west hasn't it.... Also it looks terrible for swimming around New Zealand. Looks like a repeat of Christmas 2006 could be on the cards (too cold for swimming)!

A strange Spring here with a lack of "normal weather". After a warm and dry September, and the warmest August ever, we had the coldest October since the 1940s. November has been mostly dry, and now some warmth is heading our way. Today Timaru hit 29C, which makes this the warmest day since September 14th! Tomorrow, somewhere will reach 30C, for the first 30C of the season. (3 weeks later than last year). Gisborne should be glorious the next few days.

Clear, but cold at 8C (9PM). Just got dark. The poor, cold weather of October seems almost to be over, with a few fronts early next week and then subtropical ridging influencing us for next weekend. A bit worried that the high will be too far west though, it seems to be a trend.

How on earth did you end up in Exmouth?! I think they are in the part of WA that does not even get rain in the monsoon (!) and has to rely on tropical cyclones for the only rainfall of the year! Terrible weather in NZ at the moment - it's much colder than August! Our high was a pitiful 11C, and the nationwide high was an unbelievable 17C. It's a cold late October day when no where really gets close to 20C. Tomorrow will be warmer though.

This stuff is not new, it's been there a few years. But it's useful to have this stuff all in one place. The numerical methods is particularly good, summing up all the major schemes like leapfrog and forward time/centred space pretty concisely and methodically! (And without being too dry). The notes do require reasonable exposure to maths and physics though. The meteorology is almost an aside. This stuff is practically just applied mathematics. Their section on the spectral method is especially interesting, because it is the method used at ECMWF and also GFS I think. (UKMO is fixed grid, Canadian model uses finite elements...I believe). That makes the spectral method seem more elegant, though it has limitations and they do list them. Two key advantages: (avoiding aliasing is a good one) A major disadvantage (since limited area models are pretty important...): ---- Note that they've only listed the syllabus of the courses, not the material itself. What you can access now is background reading. Anyway, a good find thanks!

Sydney Opera House was evacuated a few months ago because of a tsunami warning.

Not looking good if they're talking about this already.... Apparently a few fires have been underway down south due to strong, warm dry winds. Not helped by Dunedin hitting 23C at 2AM one morning- so much for "the Scottish City"! http://www.stuff.co.nz/the-press/news/christchurch/2868349/Canterbury-drought-likely-say-forecasters http://www.stuff.co.nz/timaru-herald/news/2872513/Fire-watch-as-green-drought-nears

My mother puts the heating on even in August, if she's cold. Clearly gone soft since living through 62/63!

Phew, what a scorcher. As expected records fell today. New September record maxima on the South Island for Alexandra and Timaru, which hit 29C and 27C respectively. At 6PM it was still 22C in Christchurch. They've had 6 days so far this month over 20C and no rain at all. It's only the first month of Spring. Relative humidities have been very low and there's been plenty of dust about. RHs varying from around 8% to 20% during the foehn, and temperatures above 20C at the same time. Winds have gusted to 50 knots in exposed places. Essentially all this is drying things out very early in the season, and with an El Nino summer on the way eastern areas are quite likely to have some real struggles on their hands. Come December we could well see dessicating nor'westers blowing all the top soil in Canterbury out to sea. Unless something changes, that is. As it stands, the nights are still longer than the days....and there's another blast of warmth heading for SE Australia and then us early next week.

A truly monumental day in New Zealand! First 80F of the season with Timaru hitting 27C. But then Alexandra beats it with a jaw dropping 29C! We haven't even reached the Spring equinox yet! Relative humidities again very low combined with high temperatures. Temperatures over 20C combined with RHs in the single digits are going to dry things out very quickly- and add into that the hot dry winds gusting to 50 knots in places.

Warmest day nationwide since April. Most places hit 20C. 17C here, but sunny all day. Tomorrow some warm air from Aussie makes its way over. 30C was recorded in Melbourne (almost a Sept record). Records may fall in the South Island tomorrow.

For the world, any desert would be the best hope...so parts of Siberia, possible Antarctica, then the multitude of warm deserts around the world. I'd hazard a guess at it being in the range of 40C? Cookie's post suggests I was miles off!