Thomas Saunders

Mesovortex is visible within the eye of #CycloneNarelle. Only the strongest storms exhibit this feature. Image from the JMA target satellite. #Queensland #Narelle

#CycloneNarelle could be the first in 21 years to make 3 separate landfalls. #Narelle #Cyclone abc.net.au/news/2026-03-1…

@bowtiedstocks How weather impacts people is significantly influenced by acclimatisation. This is well researched and its why the BOM's heatwave forecasts (even without factoring in humidity) are so complex. Eg Hobart reaches heatwave thresholds at much lower temperatures than Tennant Creek.

@TomSaundersABC Ever been to Brisbane mate? 😂

The humidity the past few weeks has been oppressive in #Sydney. And I have the proof ... but using dew point which is a far more direct and accurate measure of atmospheric moisture than RH%.

ENSO becoming more volatile? I have calculated the running 10 year mean of absolute relative NINO3.4 values (ERSST.v5). Seems to be trend here which concurs with some of the research. #ElNino #ENSO #LaNino

If El Niño develops this year as predicted by modelling (which are least accurate in Jan-Feb) lets see if we can finally avoid the misinformation about a dry summer. abc.net.au/news/2026-02-1…

#Sydney has now recorded its equal highest December maximum. Tied with 42.2C from 1957

@klunkadunka Yeah that's absolutely true - there's no chance of a Black Summer although soil moisture has fallen since September

@TomSaundersABC The years leading up to the 2019/20 event were relatively dry. This time the NSW coast has been very wet since the end of the 2019/20 event.

Graph I showed on ABC news last night. The 3 worst fire seasons since 1985 for NSW in terms of hectares burnt all have a negative Antarctic Oscillation from Sep to Dec (proxy from SAM). Some negative SAM years though, like 2000, aren't bad fire seasons - so there is hope.

There is a global misconception the Gulf Stream is the main reason western Europe has mild winters. I would argue the key is the presence of any major body of water to the west, regardless of currents. Eg Vancouver is only slightly cooler than London at a similar latitude.

@QuentinFry Put your money on a draw. So bet Australia to win series 4-0. lol

Late-July to late-August was revolting and rained every day, but since then maybe (?) the best Sydney spring in living memory. Many great days, today just one. All set for rain in the Sydney Test of course...

@DamienIluvanth I should clarify. When the impact of the weak vortex diminishes in summer, the IOD will no longer be around to bring rain - so the climate drivers will shift to ENSO, monsoon, SSTs, SAM etc

@DamienIluvanth The influence should last through November. By mid December the IOD will have weakened considerably.

The Indian Ocean Dipole index has dropped to another record. The latest weekly measurement of -1.94 is the lowest in the BOM's database extending back to 2008. Earlier monthly calculations suggest its the lowest since at least 1996.

@stillreezy No connection

@TomSaundersABC any connection to the failed Panama upwelling?

October was dry but #Sydney is still winning the rain race this year - about 4 times Melbourne, Adelaide, Canberra and Hobart.

@BowGhosn Normally wetter - but this spring it's up against a weak polar vortex which tends to bring dry weather to the east coast.

@TomSaundersABC Does this mean drier weather for NSW south coast? We need rain badly here

@krazykitkatm @JoshHoltTEN The new site might be an improvement for non weather geeks but I despise it. It's basically an App enlarged to a website - wasted blank space all over and inefficient scrolling and clicking to find what I'm after - which used to be condensed on one page.

@JoshHoltTEN @TomSaundersABC With so many complaints about the new BoM website, I find the difference in the radar images particularly concerning. Do you have any insight? facebook.com/belcoweather/p…

An October daily record of 39C is predicted for #Sydney tomorrow - along with an extreme fire danger, strong winds and a possible severe thunderstorm. The monthly record will also be broken - a mean well above 27C which easily exceeds the current record of 26.2C from 1988.

@MarkRid31548165 August was the wettest since 1998. This October is heading for a record - unless the last week of the month brings a cold snap.

@TomSaundersABC Thanks Tom, I look forward to cooler temperatures. Sydney 2025 must be close to record rainfall in August & record heat in October.

Southerly buster is moving up the #NSW coast. Kiama dropped 14C in 30 minutes with gusts to 76 km/h. Should reach #Sydney from about 5pm. Unlike most busters though - this one is triggering severe #storms.