The Northern Australian Monsoon 2020 - 2021.

[greysrigging 2,378]

She's IN ! At home just now ! The squally showers have done the old 180* turn around streaming in from the Timor Sea to the north west and the Arafura Sea to the north. 
The true indication of our Monsoon season. About a week or 10 days earlier than normal onset, although perhaps a bit later than in a general La Nina year. which might be mid December.
So no excuses now for foolish behaviour, tom foolery, poor decision making, excessive alcohol consumption, and being a bit of a goose.... the 'build up' is done and dusted, mango season is finished, so no more 'mango madness', no more telling the Judge, "sorry Your Honour, but fair dinkum mate, this 'build up' had been a real b****ard....", and the Judge nodding with complete understanding..........
Bring On The Rain !

 

[greysrigging 2,378]

A friend sent some pics from on Darwin Harbour.

A north west squall about to come in....

 

[chinandega81 191]

A trend I noticed this rainy season in Florida was that it tends to be a slow build up.....it starts out somewhat paltry and sporadic and as time progresses, the rains become more frequent as the season progresses. Is it the same for you in N. Australia? Or are you lucky enough to have it full blast from start to finish?

[greysrigging 2,378]

15 hours ago, chinandega81 said:

A trend I noticed this rainy season in Florida was that it tends to be a slow build up.....it starts out somewhat paltry and sporadic and as time progresses, the rains become more frequent as the season progresses. Is it the same for you in N. Australia? Or are you lucky enough to have it full blast from start to finish?

No, our rainy season in the deep north is a completely different weather pattern compared to the early 'build up' rains which revolve around a Kimberley region 'heat low' establishing itself ( usually late August ) in the tropical northern inland of Western Australia. The increasing heat and humidity produces convectional type storms over the Top End, including Darwin. These storms up our way are sometimes associated with 'Gulf Lines' coming east to west across the Top End from the Gulf of Carpentaria, other times 'Hector the Convector'( perhaps the only named thunderstorm in the meteorological world ) and another one known locally as the 'Labelle Cell' to our south west gives us some early rain prior to the onset of the North Australian Monsoon ( Asian actually, as the Trough moves south of the Equator and forms over the Top End at 12*S )
Our 'Dry Season' really is dry, with usually 3 ( sometimes 5 ) completely rainless months, May - Sept.
Some years the Monsoon may only form 2 or 3 times in the season, about a month apart..... these 'break' periods, the conditions revert back to 'build up' type weather patterns, with isolated showers and storms from the east and south east. Often monsoonal weather patterns coincide with the Madden-Julian Oscillation (MJO), which is the major fluctuation in tropical weather on weekly to monthly timescales. The MJO can be characterised as an eastward moving 'pulse' of cloud and rainfall near the equator that typically recurs every 30 to 60 days.
Other influence on the timing and severity or otherwise of our monsoon season is the La Nina - El Nino patterns and the IOD ( Indian Ocean Dipole ) and the subsequent SST's ( sea surface temperatures )

 

[greysrigging 2,378]

Some reading material re 'Hector the Convector'
https://blogs.unimelb.edu.au/sciencecommunication/2020/09/19/meet-hector-the-thunderstorm-that-can-tell-time/
https://www.youtube.com/watch?v=UsOpWeLWgjM

[Tyrone 2,093]

22 hours ago, greysrigging said:

She's IN ! At home just now ! The squally showers have done the old 180* turn around streaming in from the Timor Sea to the north west and the Arafura Sea to the north. 
The true indication of our Monsoon season. About a week or 10 days earlier than normal onset, although perhaps a bit later than in a general La Nina year. which might be mid December.
So no excuses now for foolish behaviour, tom foolery, poor decision making, excessive alcohol consumption, and being a bit of a goose.... the 'build up' is done and dusted, mango season is finished, so no more 'mango madness', no more telling the Judge, "sorry Your Honour, but fair dinkum mate, this 'build up' had been a real b****ard....", and the Judge nodding with complete understanding..........
Bring On The Rain !

 

Nooiceee!!!!

[greysrigging 2,378]

Rained all night, there's another inch in the gauge ( still raining  7.00am )
Lovely cool atm 25c.
!50mm ( 6"' ) in the last week of steady soaking rain....the odd squally heavier burst, but generally great garden rain !

[greysrigging 2,378]

You know you're in Darwin when some bloke is mowing the grass during a monsoonal downpour!....lol

[tropicbreeze 729]

The monsoon went all quiet yesterday, during the daytime. Only got a couple of mm rain over a 16 hour period. Then over night 8 hours of rain produced 160mm. Some other places nearby got more. This month's rainfall is running at 180% of average. There's a good chance there'll be a lot more rain before the end of December. It'll need about 20mm per day to keep the total at the 180%.

[greysrigging 2,378]

42 minutes ago, tropicbreeze said:

The monsoon went all quiet yesterday, during the daytime. Only got a couple of mm rain over a 16 hour period. Then over night 8 hours of rain produced 160mm. Some other places nearby got more. This month's rainfall is running at 180% of average. There's a good chance there'll be a lot more rain before the end of December. It'll need about 20mm per day to keep the total at the 180%.

You mob did well out there in the Outback Appalachians.....
17.3mm in the Northern 'Burbs.... ( sigh ) 246.8mm for the month so far ( 292.5mm av )

[tropicbreeze 729]

I got 164.2mm for the full 24 hours but it was a "mixed bag" around Darwin.

[greysrigging 2,378]

From the BOM ( Weekly Tropical Climate Note )
Monsoon arrives at Darwin

Friday 18 December saw a monsoon trough form across the northern Top End and an embedded weak tropical low develop in the Timor Sea. Monsoonal flow strengthened and extended south-west to the Kimberley the next day. The resulting two days of north-westerly winds from the surface to the mid-levels at Darwin satisfied the 2020-21 monsoon onset criteria, meaning that 19 December is the official monsoon onset date at Darwin for the 2020-21 northern wet season. This season’s monsoon onset date at Darwin is more than a week earlier than average (29 December), and is a month earlier than last season’s onset date (18 January 2020). The last comparable early onset was in 2016-17An early monsoon is typical of La Nina. This season, the onset was also aided by warmer than average ocean temperatures around Australia and the interaction of the MJO and other tropical waves to the Australian region .A deepening tropical low (03U) crossed the Kimberley coast and tracked through the district’s south and is not expected to develop into a tropical cyclone. A weak tropical low is currently located just outside the North-West Australia tropical cyclone region. There is a low risk for it to impact Cocos Islands for the coming week. However, international tropical cyclone forecast models, indicate there is a significantly increased risk for a tropical cyclone development in the central Indian Ocean to the eastern Madagascar at the end of December into early January 2021.

Madden–Julian Oscillation becomes weak in the Western Pacific. The Madden–Julian Oscillation (MJO) has recently been active in the eastern Maritime Continent, assisting the development of the monsoon trough across the northern Top End and the Kimberley last week. The weak MJO pulse is currently meandering from the eastern Maritime Continent into the Western Pacific region. At this time of the year, an active MJO in the Western Pacific is typically associated with above-average rainfall across far northern Australia and the northern Coral Sea. Climate models agree the MJO will be weak this week, with some predicting it will remain so into early January. However, the Bureau’s model indicates the MJO could strengthen over the western Indian Ocean in early January 2021.

[greysrigging 2,378]

Huge storm over Darwin and the rural areas... over 100mm ( 4" ) in a coupla hours at Batchelor and Noonamah ( the Outback Appalachians )
Even Leanyer Heights where I live is more than 50mm ( 2" ) in the hour since it started to rain !
 

[greysrigging 2,378]

3" in three hours.... yeah, I'll take it !

[greysrigging 2,378]

Nigh on 100mm ( 4" ) since 5.00pm Boxing Day ! 

[tropicbreeze 729]

11 hours ago, greysrigging said:

Nigh on 100mm ( 4" ) since 5.00pm Boxing Day ! 

I got 116mm out of that, so now running at 202% of December average. The monsoon took a couple of days break over Christmas. Maybe didn't want to get Santa's presents wet as his sleigh doesn't have any weather protection. Technically, the monsoon has moved back over Indonesia.

[greysrigging 2,378]

5 minutes ago, tropicbreeze said:

I got 116mm out of that, so now running at 202% of December average. The monsoon took a couple of days break over Christmas. Maybe didn't want to get Santa's presents wet as his sleigh doesn't have any weather protection. Technically, the monsoon has moved back over Indonesia.

Measured 95.3mm..... yeah, pretty happy with that !

[greysrigging 2,378]

Bit of activity overnight and this morning......

 

[greysrigging 2,378]

Nice drop overnight and this morning.
A view up and down my street.

 

[greysrigging 2,378]

Darwin, Northern Territory of Australia ( 12.46*S )
2020 Rainfall, Max and Min temps.
Jan - 402.0mm, 32.8c, 26.0c
Feb - 216.6mm, 33.4c, 26.8c
Mar - 278.2mm, 33.2c, 25.4c
Apr - 115.6mm, 33.7c, 25.1c
May - 1.4mm, 32.1c, 22.4c
Jun - 1.0mm, 32.4c, 21.1c
Jul - 0.0mm, 32.0c, 19.2c
Aug - 0.0mm, 32.6c, 21.0c
Sep - 87.6mm, 33.9c, 23.7c
Oct - 162.0mm, 33.6c, 25.3c
Nov - 93.0mm, 35.0c, 25.8c
Dec - 382.0mm, 32.6c, 25.0c

2020 Totals and means
Rainfall - 1740.2mm, Max temp - 33.1c, Min temp - 23.7c. Yearly mean of 28.4c
Hottest day 37.0c on Sept 8th and Nov 17th
Coldest day 25.0c on May 22nd
Hottest night 29.7c on Feb 26th|
Coldest night 16.2c on July 30th
Wettest day 113mm on Oct 8th.

[greysrigging 2,378]

Been quiet in the Darwin region for the last week.....as per usual, a Gulf Cyclone ( Imogen ) tracked East into North Queensland and stole our rain. We have had a run of hot dry westerlies ( although I scored my first 2021 rain this morning 4mm ).
Some local photography from the guys and gals on our local weather FB group.

 

[greysrigging 2,378]

Bit of activity around town the last few days.
Hector the Convector has been going off over the Tiwi Islands to our North.

Groote Eylandt in the Gulf picked up 26mm from this cell.

Good lookin' structure over at Gove on the north eastern tip of the Territory.

And a bit happening around Darwin too.....

East Point.

[tropicbreeze 729]

For a monsoon break period my rainfall totals have been fairly high. These are the daily totals for this month so far
5.8
1.2
0.0
0.0
15.0
0.0
83.2
14.4
0.0
1.0
49.0
35.2
31.4
==========
236.2

In the same period Darwin Airport 65.8, and Noonamah AWS (Weddell) 168.8

Pity Coolalinga doesn't have an official rain gauge, they've had a lot more rain than I have.

[greysrigging 2,378]

^^ 103.6mm here at home in Leanyer so far this month. Was out at Hopewell Rd, Berry Springs this morning.... one can easily see there has been way more rain out that way than in Town.
Nice little drop as I type right now  ( 1.25pm ). 12.5mm so far
From Pilkos's 'Chat on Weather', Darwin.
"A very tropical and quite uncomfortable morning here in the Top End so far.30.9 at the Airport and the “feels like” temp is 37.1 so it’s pushing the boundaries of ones sanity at the moment. Darwin and immediate surrounds missed the action yesterday as a bit of NE steer took over and pushed everything just south of the city. Today tho does look a little better with more favourable conditions for Darwin and hopefully that means free showers for all Models still look keen for a monsoon trough to develop to the north of the Top End in the coming days, but it’s still a bit of coin tossing as to its strength and main area of activity. Off the far north WA coast is looking the best bet for the most concentrated activity, watch for potential low development, but realistically nothing is etched in stone just yet. A strengthening ridge thru central and southern Australia in coming days will push most of the activity to the Top End, especially the NW Top End before moisture again spreads south from next week.

The last few days has seen some pretty impressive lightning shooting about, so please take care out there. Some of these bolts are shooting well clear of the storm front and as such you don’t need to be standing in the rain to get hit."

[greysrigging 2,378]

Look at the filthy conditions yesterday afternoon.....about as bad as it gets !

Then a massive storm last night seemingly right over the top of my bedroom....... when you 'hear' and 'smell' the lightning before you see the flashes you know its close.
I haven't checked my gauge yet, but this is about a mile from me...

[greysrigging 2,378]

Just horrendous !

[Tyrone 2,093]

On 1/15/2021 at 3:25 AM, greysrigging said:

Look at the filthy conditions yesterday afternoon.....about as bad as it gets !

Then a massive storm last night seemingly right over the top of my bedroom....... when you 'hear' and 'smell' the lightning before you see the flashes you know its close.
I haven't checked my gauge yet, but this is about a mile from me...

30.7C dewpoints. Wow. The air has that much heat energy stored in it. So hot and steamy mould would just die!

[greysrigging 2,378]

We whinge about it....but then again it all produces this.....late this arvo.

 

[greysrigging 2,378]

This is about as good as it gets temp wise in Darwin during the 'Wet' 
Only 26c at noon and topped out at 27.6c ( atm 6.00pm ).
Drizzly rain, heavy overcast all day, only 5mm of rain.... wonderfully cool and damp !

[greysrigging 2,378]

No complaints at mid / late arvo in Darwin with the first of the impending monsoonal squalls sweeping across the city and suburbs.

 

Edited January 23 by greysrigging

[greysrigging 2,378]

Light rain most of yesterday and overnight....the forecast for the rest of the month is very promising 
www.bom.gov.au/nt/forecasts/darwin.shtml?fbclid=IwAR2ekCecDpMp3SoDk14Yf7jlXWC8dSzicH3jMyg75bEsXbbEOIQL3gK6HGQ
BoM have really ramped our rainfall up for the coming week.
The satellite is showing an impressive monsoon surge developing across the waters to our north and this looks set to pull down over the Top End in coming days.
Showers, storms becoming more frequent across the Top End and these will be accompanied by squally winds at times.
A weak low near Gove looks set to develop slowly whilst remaining slow moving.
Ya gotta love a good monsoon !



A typical monsoonal squall screaming in from the Arafura Sea just now at Gunn Point ( a little to the east of Darwin )|
Pic/images/text by Nikko Gilbert.
"A proper off the ocean Monsoon showers incoming.
Amazing how much of a punch this little shower is giving. Gust in excess of 56.9kph (will be higher, just my weather station doesn't pick up the strongest gust unless it happens to transmit the data at the exact right time) but still amazing...these things are stronger then thunderstorms in some cases".

[greysrigging 2,378]

The black lines are 25mm increments so around 75mm atm here in Leanyer Heights. Real total at 9.00am when I empty it.

[greysrigging 2,378]

Australian Bureau of Meteorology
Tropical Cyclone Warning Centre

Media: The Standard Emergency Warning Signal should NOT be used with this warning.

TOP PRIORITY FOR IMMEDIATE BROADCAST
TROPICAL CYCLONE ADVICE NUMBER 7
Issued at 7:44 am EST on Wednesday 27 January 2021

Headline:
Developing tropical low is slow-moving off the western Cape York Peninsula coast.

Areas Affected:
Warning Zone
Mornington Island, and Karumba to Aurukun, including Kowanyama and Pormpuraaw, and nearby inland areas.

Watch Zone
Aurukun to Weipa.

Cancelled Zone
None.

Details of Tropical Low at 7:00 am AEST [6:30 am ACST]:
Intensity: Tropical Low, sustained winds near the centre of 45 kilometres per hour with wind gusts to 85 kilometres per hour.

Location: within 55 kilometres of 14.8 degrees South 141.6 degrees East, estimated to be 80 kilometres north northwest of Kowanyama and 330 kilometres northeast of Mornington Island.

Movement: east northeast at 8 kilometres per hour.

The tropical low is expected to remain slow-moving off the western Cape York Peninsula coast and may develop into a tropical cyclone on Thursday. The system should remain slow-moving in the southeastern region of the Gulf of Carpentaria for a few days, after which it may cross the western Cape York Peninsula coast.

Hazards:
HEAVY RAINFALL is forecast about western parts of Cape York Peninsula for the next several days with the potential for 150 to 200 millimetres per day for multiple days. The most likely areas to see these rainfall totals will be coastal parts between Weipa and Gilbert River Mouth.

ABNORMALLY HIGH TIDES are expected between the Torres Strait Islands and Pormpuraaw during the next several days. Large waves may produce minor flooding along the foreshore. People living in areas likely to be affected by this flooding should take measures to protect their property as much as possible and be prepared to help their neighbours.

GALES with gusts to 110 kilometres per hour may develop about Mornington Island, and communities between Aurukun to Karumba, and nearby inland areas, on Thursday morning.

DESTRUCTIVE winds with gusts to 150 kilometres per hour may develop from Thursday night if the system continues to intensify.

GALES may extend north to areas between Aurukun and Weipa later on Thursday or on Friday if the system follows a more northward track.

[greysrigging 2,378]

483mm  ( 19" ) so far this month. A few days to go in the month and may well get to the old 2'  ( 600mm ) mark by then. 
I'm at about 1130mm ( 45" ) since the start of the season on Oct 1st.

[greysrigging 2,378]

Ok then....approaching ( but not quite there yet as the memories of the two previous failed wets are strong ) the, "ok rain, that's enough...." scenario.
From a mate in Palmerston...
"Good morning troops. Holy moly what a night of torrential showers, a rumble of thunder and a chorus of flaming tree frogs to keep the neighbourhood awake!
Absolutely belted down in Gray and it’s not 9am yet for my “official” reading but we have cracked 100mm since 9 yesterday.
So another 103.6mm on the last 24 hours.
331.4mm in last 72 hours.
Yesterday the frogs had gum boots on.
Today they have gum boots on AND an umbrella...
Radar is looking like a very wet couple of hours as a few lines of monsoonal squalls roll in.
REAL monsoonal weather at last !"

And when I went out to check my gauge this morning,,,,,no idea who it is....lol !

[greysrigging 2,378]

With one full day of recording for the month of January remaining, it seems certain I will crack the 700mm mark for the month. Up until 9.00m this morning ( just now ) I'm at 687.3mm. Still full overcast and raining lightly as I type.
Since this monsoonal rain started 8 days ago....
23rd - 12.2mm
24th - 42.0mm
25th - 78.2mm
26th - 56.4mm
27th - 33.3mm
28th - 63.4mm
29th - 86.4mm
30th - 53.4mm
That's 425.3mm of consistent soaking type rain..... palms are loving it !

[greysrigging 2,378]

Bloody hell !! If this scenario comes off..... that's 1000mm ( 40" ) in the next 8 days ! !

[greysrigging 2,378]

I ended up with 691.5mm  ( 27.2" )for January... a definite pass mark... monthly mean rainfall is 447.8mm

[tropicbreeze 729]

My total for January was 551mm, 147.9% of average. Last year January totalled 446.8mm.  

Darwin's water storage is up to 59%, up from 54.4% this time last year.

[greysrigging 2,378]

Big storm impacting the Darwin region overnight and this morning....
"Northern Territory Police, Fire and Emergency Services
Heavy Rain overnight – impacting roads and traffic conditions in the Greater Darwin area
We have had some heavy rain overnight and the forecast indicates further rain today. NT Police are taking the opportunity to remind people to be aware of the the possibility of localised flooding occurring, the need to drive to the road conditions, slow down, maintain a safe distance from other road users and to turn on headlights when visibility is impaired.
Impacted areas at this time in the Greater Darwin area include:
1. Stuart Highway Pinelands south of McMillan’s Road Intersection [Inbound lane to Darwin] A number of cars have become stranded after being affected by water, with multiple reports of water over the road
2. McMillan’s Road & Charles Eaton Drive, Rapid Creek [water over the road] With Minor Flood Level of 2.829 metres having been met at 4:50am and the possibility of variations as the weather continues.
Water levels and rainfall can impact conditions quickly and road users are reminded to use the Road Report website to check local conditions road.report.nt.gov.au & secure.nt.gov.au
Department of Infrastructure, Planning and Logistics, NTES & NT Police have and are continuing to respond. Please take notice of all traffic controls."

Here at home got smashed by a beauty early this morning. Currently 101.4mm and still raining. Very windy at one stage. I noticed a gust of 100km in the Harbour, so a wild night up town that's for sure !