How’s the humidity in SEQ at the moment? All this rain and moisture, and today the sun came out and turned the place into a sauna. Felt more like January at times than it did May.
We should be having clear, cool nights with mild, sunny days at this time of year. All the rain and humidity just feels wrong. And don’t get me started on the mould appearing everywhere…
Yes, it seems very off down in the ACT too.
It was actually warm overnight last night by our standards. 15° was the minimum, but the average is 1°.
We’ve had a few days in the 20’s the last few days too (excluding today) which is unusual for May.
The average is closer to 3C in May but you’re right nevertheless: minima have been close to record levels. All due to the unseasonal push of tropical maritime air enveloping just about the entire eastern half of the continent. Warrnambool was another place to set a record for overnight min (also 15). Even Perisher Valley was around 8C.
Bungendore has had multiple nights above 10C, peaking at 14C on Sunday morning. A cursory look at the last few years suggests minima above 10C aren’t unheard of- particularly in our new climate- but rarely do you get more than one or two nights in a row above 10C in May.
More typical May weather this week for the ACT: cool to cold nights and crisp sunny days. The mild overnight temps this autumn and the overall dampness have delayed autumn colour and resulted in a mouse plague in Bungendore. I am trapping some most nights.
I presume that is a continuation of the plague reported last year?
I wonder the strange weather we have, could of happened before the industrial revolution, it is more that the air flows we are having are from the Tropics. Or because of the climate change means we will get more air flows from the north and less southernly air flows? What causes weather to decide this year the airflows will come from the north? I heard in parts of the US they were getting a very cool Spring.
Now I am asking deep questions maybe I need to go back to Uni and study for 10 years to find some sort of an answer instead of posting on a forum 
.
Yes it is AGW, but the overall impact in the Northern Hemisphere and Southern Hemisphere is quite different (even though it’s a warming trend everywhere).
There’s more scope for the jetstream to deviate in the Northern Hemisphere due to all the land at high latitudes, so some places get extreme heat (India/Pakistan at the moment) whilst others get unusual cold (midwest USA). The jetstream is disturbed because the polar regions of the NH are warming faster than the midlatitudes, and the presence of land gives rise to extreme temperatures at both ends of the spectrum. The land to the south of the polar regions also means that heat can easily transfer from the midlatitudes to the poles, in a way that’s impossible in the Southern Hemisphere. North America in particular has just the right geography to get the full effect of the wavy jetstream; there’s no east/west mountain range like the Himalayas or Alps to block polar and tropical airmasses, so places like the Midwest US get extreme heat one minute and extreme cold the next. This is also why tornadoes form in this region: extreme instability from the clashing of polar and tropical airmasses.
The Southern Hemisphere is very different: it’s pretty much all ocean at high latitudes where the polar jet resides. There is no mechanism for heat at the midlatitudes (Australia) to transfer efficiently to the high latitudes (Antarctica). The result is that Antarctica is warming more slowly than the midlatitudes, which has the effect of keeping the polar jet closer to Antarctica. This means less cold fronts reaching Australian latitudes and more tropical influence overall for SE Australia.
The only place in the SH where the jetstream can somewhat loop up to the midlatitudes is in South America. Extreme cold waves can occur in South America, even up to the tropical latitudes at times. Buenos Aires had snow to sea level in 2007; they are on the same latitude (35S) as Nowra.
In short: I don’t think Canberra will ever see a significant snowfall again, and skiing may well be impossible toward the end of the century in the Alps. Unless something happens which really disturbs the jetstream of course. A sudden stratospheric warming can do it, and this was part of the reason for the unusual westerlies well into spring and summer in 2019…which had disastrous consequences. But these events are rare.
TL; DR: Northern Hemisphere has greater warming overall, but fluctuations in the jetstream bring more variable weather. Places in the Southern Hemisphere are almost always warmer than average, but less spectacularly so.
Wow, snow at location similar to Nowra . (Maybe it did happen back in the 1800s but not this century).
Thank you you have great knowledge in this area. Appreciate your post, I learnt something.
You know the mice are one reason why I wouldn’t want to live west of the Dividing Range. I heard the horror stories of too many people both in the recent plague and ones in years gone by and it sounds disgusting. The odd rat here in Brisbane is bad enough.
Thanks for the info re AGW impacts too. In my simple mind it feels like a very tropical airmass here which is leaving temps and relative humidity at those levels - the RH was in the 90s %-wise for most of this morning. I know the westerlies have other impacts but what I’d give for a good “Ekka Westerly” to blow this humidity out right now and cool the place down…
The site I was looking at provides daily averages for Canberra Airport. According to it, the average minimum at Canberra Airport on May 15th is 1.0°C 
Significantly colder than the 14.7°C actually recorded on May 15th this year
Note: the “official” minimum for May 15th, according to the BOM’s 9am-9am reporting standard is 14.1°C which was actually recorded at 9:00am on May 14th.
The overnight low was 14.7°C
I use the new Canberra Airport site; the average there is 2.4. Colder than I thought. Braidwood however is 2.7 which is probably closer to reality in Bungendore. I think this is because Bungendore and Braidwood are more prone to milder coastal air in autumn. I don’t think there is a reliable site for daily averages; the BOM doesn’t really track them (unlike the NOAA in the US). But logically, May 15 is smack bang in the middle of the month so the daily average would approximate the monthly average.
Stats from 2008-2022 better reflect the reality these days anyhow…
Canberra Airport (new site):
According to locals, this is the worst mice have been for at least 20-25 years. We don’t usually get them in plague proportions like the grain growing regions to the west. I think they are a problem in Braidwood as well and that’s firmly east of the range. Even suburban Canberra would have mice right now.
Rockhampton is still below average for the year for rainfall so is Yeppoon. Every time a rain event was predicted to come here it went further south. This is the first month this year we have had average /above average rainfall.
Mount Morgan south of Rockhampton the dam is 14.5 percent and the council is still trucking water in to the town.
5.1 deg above
As I may have mentioned here several posts back or not it’s been a terrible season. October started off stormy and just scraping the rainfall average. November was super duper wet and crazy humid felt like March. December, first week and a bit was wet then the taps went off . Didn’t rain much until March and it was just a storm . Didn’t rain again until April but again below average and nothing substantial.
October the humidity really cranked up and it hasn’t really gone down much since. To top it off the days in summer were cloudless , windless (even though my town is right on the beach) and very humid. At times the humidity was more like Singapore than Central Qld. We had dew points around 28 deg for 2 weeks at one point it was that bad.
Mount Morgan south of Rocky the level has been dropping at the dam since 2017… I think 2017 was the last year Rockhampton had average rainfall but there is missing data so can’t confirm.
Wow yes that is bad… I was in Singapore in June 2018 - I knew the temp range would like 26 min - 34 max and that it would be humid, but yes, didn’t know humidity could be like that! It was hot hot hot… I was outside and sweating whilst just sitting down… Now I know!
I hate the humidity in summer, this is the wrong time of the year for it .Had to use my air conditioner
We’re still having to use the air conditioner this late in May. It’s 26 deg today in Yeppoon (feels like temperature is pushing 28/29 deg) 2 deg warmer than average the night was 20.7 (average is 15.7 usually)
I’ve lived here 10 years and never had to use it in May before or start using it as early as October.
Humidity was 100 percent this morning and has only dropped to 83 percent at 11am and now around 89 percent. No rain though just a bit of cloud .
It has to cool down eventually… maybe towards the solstice . Who knows. Where is the dry SW winds or the lower humidity ?
The highs aren’t even going over the continent yet.]
Yeppoon has been battling humidity since early October just hasn’t let up .
This time last year we were cold lol. Wonder how short winter will be this year in Qld . July- September?
Ours was more like 22-24 min max 29 /30 humidity 65 percent but at times 75 percent or more and no rain though . Kept thinking it would rain but it kept going to SE Qld instead of Central Qld. 28 degrees with high humidity and no breeze and a high dew point can feel yuk you just go outside and instantly get a wet tshirt and start sweating.
Be interesting to see our power bill at the end of June given we are still using fans and air conditoning .
Normally Canberra would be top or second top of that list; there have been probably slightly more rain days here in Bungendore due to our greater exposure to easterly rain events. Obviously a huge bias towards easterly derived rain so far this year, leaving the regions exposed to ‘traditional’ W or SW rain events fairly dry. The driest area relative to average has actually been western Tasmania.
The developing negative Indian Ocean Dipole (‘IOD’) may correct this imbalance somewhat through winter and spring, mainly benefiting Melbourne and perhaps Adelaide. Negative IODs generally bring about northwesterly cloudbands and associated rain, particularly as they interact with cold fronts. The cold fronts are the big question this year, though surely some will develop come July/August. I am still tipping a woeful snow season, particularly if the IOD influence is dominant (more ‘warm’ rain events).
That’s such a potentially misleading fact to provide without context / interpretation - e.g. Perth’s average days of rainfall for Jan - May inclusive is 18 days, so 113 days without rain from 1st Jan - 24th June (143 days) is actually well above average.
That can’t be right.
Bear in mind a ‘rain day’ is defined by the BOM as any day above 0.2 mm (since values of 0.2 or lower can constitute dew rather than rain). So you could have a day with a light shower that registers 0.2 mm or less, but it would still count as a dry day.
Still, these are semantics.