NH Fall / SH Spring 2022 Discussion Thread

La Nina Has Returned
( source: Weatherzone )


The Bureau of Meteorology has today declared the return of La Niña for a third consecutive season, solidifying the prospect of above-average rain and flooding in parts of Australia during the next few months.
Back in June this year, the Bureau declared the end of the 2021/22 La Niña event that had underpinned widespread rain and flooding over eastern Australia earlier in the year.

Since then, the Pacific Ocean has remained in a La Niña-like state according to the Bureau of Meteorology. However, some other international climate monitoring organisations, including the U.S. Climate Prediction Centre (CPC) and Japan’s JMA, continued to classify the Pacific as being in La Niña through the middle of this year.
Today’s declaration of La Niña brings the Bureau of Meteorology into line with the rest of the world in recognising that La Niña is officially underway in the Pacific Ocean.

Three-in-a-row

La Niña was in place during the last two Southern Hemisphere summers. The first event occurred between late-September 2020 and March 2021, followed by a second La Niña from November 2021 to June 2022.
It is not uncommon to see La Niña occurring over two consecutive seasons. This happened as recently as 2020-22 and 2010-12.
However, it is rare to see three consecutive La Niña events. Prior to 2020, the U.S. CPC only recognise two triple-dip events in records dating back to 1950 (1973-1976 and 1998-2001). However, the Bureau of Meteorology also classify 1954 to 1957 as a triple-dip La Niña, making it three triple La Niña events between 1950 and 2019.


What does this mean for Australia’s weather?

The official return of La Niña this week increases the likelihood of above average rain and flooding over eastern and northern Australia during the rest of spring and early summer. It also reduces the chance of extremely hot days and will likely lessen the intensity of heatwaves, while at the same time suppressing the risk of bushfires in eastern Australia.


Based on current forecasts, this La Niña episode is expected to peak during spring (most likely around November) and then weaken in early-to-mid summer. Most forecast models suggest the Pacific will return to a neutral state early next year, meaning neither La Niña nor El Niño are occurring.

This outlook suggests that the strongest effects of this current La Niña will be in spring and early summer, before its influence on Australia’s weather starts to wane early in 2023.


It is worth pointing out that no two La Niña events are the same and places that experienced flooding during last season’s La Niña are not guaranteed to see more flooding in the coming months.
However, with La Niña in place and a negative Indian Ocean Dipole (IOD) and positive Southern Annular Mode (SAM) also

might aswell kill maself

FIZZER FAIL OF THE GRAND CENTURY TODAY was forecast to be 22C but was 15C and rain all day

worthless braindamaged mongos
dont quit your day jobs BOM BUMMERS

Big Snowstorm Coming This Weekend
( source: Weatherzone )



Just when you thought it was all over, the snow gods still have a gift in store.
A reasonably heavy spring snowfall will coat the mountains of NSW and Victoria over the weekend, with snowfalls in the range of 25 to 50 cm likely over the next three-to-four days. Tasmania will miss out on most of the snow from this system as the coldest air tracks north of Bass Strait.
The snow should start around the middle of Friday, as a cold front crosses southeastern Australia. The position of the front can be seen on the Friday night synoptic chart below.


In the wake of that front, snow should fall down to about 1200 metres on Saturday and 1400 metres on Sunday, before the level drops back down to around 1200 metres again on Monday after a second front moves through later on Sunday.
This will be a very handy top-up for snow-lovers who are planning a quick ski or snowboard trip before the end of the season on the October long weekend (Oct 1 to 3).
Last week in our regular Weatherzone snow season weekly update, we told you the spring melt was well and truly on, with patches appearing across the slopes. Those patches have widened significantly in the past week, aided by rain at times.
The official snow depth measured by Snowy Hydro at Spencers Creek in NSW – roughly halfway between the ski resorts of Perisher and Thredbo – was measured on Sep 13 at 170.2 cm after a reading of 183.6 cm last week.
That's still a very handy base in higher parts of the mountains for this time of year, and while this weekend's snow will probably cover the grass patches for just a couple of days (snow bonds to an existing snowpack better than to grass when the ground warms in spring), it will still help preserve the existing cover.
The fresh snowfalls should make for some fun turns in wettish powder for those who brave the coming weekend's wild and windy weather.

Image: The melt is on but those grass patches should fill for a couple of days after this weekend's snowfalls. Source: Author's pic.

Let's move on to our weekly update of conditions at the ski resorts.

Victoria
Mt Hotham is down to six of 12 lifts still open, although as long as the Heavenly Valley quad chair is open (which it is), you're still looking at some of Australia's best in-bounds ski and snowboard terrain.
Falls Creek still has most of their lifts open, while Mt Buller is down to 12 of 20 lits, with the best runs on the mountain's south side and in snowmaking areas. Check the highlighted links for updated info.
Australia's lowest mainland resort Mt Baw Baw is now down to just one lift, but it might squeeze another week of operations with the chance of another lift or two next week if this weekend's snow falls low enough.

Image: See what we said about great conditions still available up high? The Hotham back country looking sweet this week.

NSW
Thredbo still has most of its lifts spinning with great conditions up high, while Charlotte Pass has now officially become the first and last Australian resort this year to have all lifts running (it has five).
Over at Perisher, lifts at Smiggin Holes have closed for the season, but the other three areas kick on, with 34 lifts in Perisher, Blue Cow and Guthega expected to run over the weekend. Again, please check the highlighted links for updates.

Tasmania
It's been a bleak old Tassie season with more rain than snow, and as mentioned, this weekend's snowfalls will largely bypass our southernmost state. It could be game over for Mt Mawson and Ben Lomond for season 2022.

Dews reached 67 in the Aleutians

First half of September is averaging 86.1/52.5 f, the high is only a degree cooler than the average July. And that’s including a 55 f high.

8/15 days have hit 90 so far, that’s already tied for the most ever in September. 

Some rain forecast early next week. Having substantial rain is rare this time of year.

Another epic troll for Paris region (lightning map from Sep 14):

First ground frost of the season in the outer suburbs. Here's Fontainebleau's curve from today:

Getting close. Perhaps the next storm will be a direct hit.