NOTICE!

The Weatherzone forum has now closed and is in read-only mode until the 1st of November when it will close permanently. We would like to thank everyone who has contributed over the past 18 years.

If you would like to continue the discussion you can follow us on Facebook and Twitter or participate in discussions at AusWeather or Ski.com.au forums.

Page 8 of 138 < 1 2 ... 6 7 8 9 10 ... 137 138 >
Topic Options
#1485076 - 11/01/2019 14:34 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
Stormy3 Offline
Weatherzone Addict

Registered: 12/06/2013
Posts: 1988
Loc: Ellalong,10kms SW of Cessnock ...
I was bought up in the 60's never seen it this dry around here.


Edited by Stormy3 (11/01/2019 14:35)
_________________________
https://www.facebook.com/supercell1
Click here for Ellalong weathercam,The camera is facing west towards the Wollombi,Putty area,the video live stream will be online longer, if any storms or severe weather.

Top
#1485078 - 11/01/2019 14:46 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
NotsohopefulPete Offline
Weatherzone Addict

Registered: 24/12/2008
Posts: 1405
Loc: Toowoomba
I am older but definitely no wiser. It is so frustrating to have to see this pattern constantly. I occasionally look at rainfall deciles for many months and years to try to figure it out. Although SE NSW seems to be doing well currently.


Edited by NotsohopefulPete (11/01/2019 14:48)

Top
#1485080 - 11/01/2019 14:53 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
LDRcycles Offline
Weather Freak

Registered: 14/03/2017
Posts: 108
Loc: Kin Kin, Qld
I found these forums that day, as anyone looking at the radar could see what was about to happen (though I couldn't have guessed just how awful it turned out to be) yet there were no warnings being issued.

Obviously the two events differed substantially, but given the inflow to Wivenhoe in 2011 was about 800,000 ML more than 1975, the dam clearly achieved a great deal. The only way to improve on it would be dams further up in the catchment.

Top
#1485081 - 11/01/2019 14:55 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: LDRcycles]
Ken Kato Offline
Meteorological Motor Mouth

Registered: 05/03/2012
Posts: 6090
Originally Posted By: LDRcycles
I found these forums that day, as anyone looking at the radar could see what was about to happen (though I couldn't have guessed just how awful it turned out to be) yet there were no warnings being issued.

If I recall correctly, I think there was a warning in place at the time that mentioned the risk of flash flooding, but it didn't reflect the exceptional and historic nature of the flooding that was to evolve.

Top
#1485086 - 11/01/2019 15:58 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Ken Kato]
Flowin Offline
Weather Freak

Registered: 15/10/2017
Posts: 966
Loc: Pinjarra Hills, Qld
Originally Posted By: Ken Kato

If I recall correctly, I think there was a warning in place at the time that mentioned the risk of flash flooding, but it didn't reflect the exceptional and historic nature of the flooding that was to evolve.


And that is exactly the challenge with flash flooding, all that can be forecast is the risk, not the location, time and magnitude. Flash floods happen so quickly it is only possible to forewarn of a general risk in the area, and then reactively warn when levels seen to rise quickly at gauges, intense rain is seen, or reports come in.
_________________________
Models are for estimating and gauges are for knowledge.

Top
#1485096 - 11/01/2019 16:23 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
TWEEDSTORM Offline
Weatherzone Addict

Registered: 08/01/2012
Posts: 1044
Loc: Tweed Heads NSW
Won't have to worry about flash floods in this region for now.Dry as the desert around here.The frustration is seeing storms marching through the Sydney / south and central coast of NSW, day after day after day while we sit here and swelter under a boring partly cloudy sky with no end to it in sight.

Top
#1485097 - 11/01/2019 16:34 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
Ken Kato Offline
Meteorological Motor Mouth

Registered: 05/03/2012
Posts: 6090




Indeed Flowin, it's hard to predict exactly how devastating a flood event will or won't be just by looking at the radar.

For example, there's been numerous times in the past (including in the years after 2011) when similar radar patterns have occurred in similar areas with near-stationary radar returns of similar magnitude that didn't result in the flooding as devastating as 2011.... and I've also personally seen similar big sharp rises in river height plots which also didn't result in flooding (both in QLD and other states) as devastating as Jan 2011. So while persistent precip over an area and big sudden rises in stream heights are two big factors that can't be ignored, only relying on those two things to predict devastating flooding would generate many false alarms every year and cause complacency. As already mentioned by others, one of the things that set 2011 apart from many other years was just how saturated the catchments were compared to the other years.

There's also many other factors involved that govern how easily a stream or river floods, how rapidly and when, including the nature of the stream itself, where the heavy rainfall occurs with respect to the part of the stream and what the rainfall rate is, and how saturated the catchments are.

Anyway the above maps show the longer term trends in the number of annual wet days (1mm/day or greater) and number of dry days in a row (max run of days with less than 1mm).
I'm not 100% sure if the "days/100yrs" part refers to some period used for a running average or not though but there is a noticeable trend nevertheless (tending to be more pronounced in the last few decades similar to various other changes).

The link is here for anyone interested:
http://www.bom.gov.au/climate/change/index.shtml#tabs=Tracker&tracker=trend-maps

Top
#1485098 - 11/01/2019 16:42 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
CirrusFibratus Offline
Weather Freak

Registered: 17/09/2015
Posts: 477
Loc: Strathpine, QLD
Does anyone have a link to a thread following the 2011 events? Would be fascinating to read about the events as they unfolded.
_________________________
Wunderground station ID: IQUEENSL296

Top
#1485116 - 11/01/2019 18:02 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: CirrusFibratus]
Foehn Correspondent Offline
Weather Freak

Registered: 01/11/2001
Posts: 675
Loc: Bardon 4065
Originally Posted By: CirrusFibratus
Does anyone have a link to a thread following the 2011 events? Would be fascinating to read about the events as they unfolded.


It started here and then on the last page (p300 and something it was split - links are there on the last page.)

http://forum.weatherzone.com.au/ubbthreads.php/topics/924648/1
_________________________
My Flickr Page

Top
#1485119 - 11/01/2019 18:17 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Foehn Correspondent]
CirrusFibratus Offline
Weather Freak

Registered: 17/09/2015
Posts: 477
Loc: Strathpine, QLD
Originally Posted By: Foehn Correspondent
Originally Posted By: CirrusFibratus
Does anyone have a link to a thread following the 2011 events? Would be fascinating to read about the events as they unfolded.


It started here and then on the last page (p300 and something it was split - links are there on the last page.)

http://forum.weatherzone.com.au/ubbthreads.php/topics/924648/1

Thank you Foehn.
_________________________
Wunderground station ID: IQUEENSL296

Top
#1485122 - 11/01/2019 18:21 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
Mega Offline
Meteorological Motor Mouth

Registered: 03/02/2003
Posts: 7899
Loc: Maryborough, Wide Bay, QLD
Watch the trajectory of the next high and the associated big swab of dry air it brings up from the south:


Top
#1485131 - 11/01/2019 18:44 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
TWEEDSTORM Offline
Weatherzone Addict

Registered: 08/01/2012
Posts: 1044
Loc: Tweed Heads NSW
Wow! Good time lapse Mega.Ive lived up here for 12 years now, originally from Sydney.This is the worst for me. To put it politely since living here I've really come to detest highs particularly the Squidge.Seen one really wet summer but can't remember what year that was.Noticed the weather up here is notorious for getting into ruts.W eeks of sunny weather, weeks of windy weather, weeks of showery weather but never weeks of stormy weather.Thats it in a nutshell but have seen some real good storms as well.You just don't hold your breath waiting for em

Top
#1485160 - 11/01/2019 20:56 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: TWEEDSTORM]
Nature's Fury Offline
Weatherzone Addict

Registered: 29/11/2009
Posts: 2545
Loc: Brisbane Western Suburbs
Some great posts guys. Very interesting data and stories.

To elaborate on my earlier point I think that the changing climate patterns in SEQ makes a major flood of the Brisbane River increasingly less likely.

It's clear that we're getting ever drier and hotter. We've had 9 of the 10 hottest recorded years in the last 10 years. We've also had 3 extremely warm winters in SEQ and nationally, yet these have all occurred in completely different climatic set-ups (e.g. ENSO, IOD, SAM). SEQ habitually gets repetitive long stretches of dry weather like we're seeing at the moment, with data suggesting increased high pressure/ridging. There's also a significant decrease in ECLs affecting SEQ since the 70s, less tropical cyclones overall and despite warming sea temperatures they aren't making it down to SEQ from the ocean.

So what does that all mean? We're getting hotter and drier. When we do get rain events they are much wetter and more powerful, whether they be frontal, storm or tropical, because the air and sea are warmer and so there's more energy and evaporation. Ken has discussed this before in more detail.

But that doesn't equal big river flooding events. It just means that we now need an exceptional exceptional event in exactly the right place over the Brisbane River catchment (to negate the dams) because catchments have to be primed and flooded in the same event.

Even without Wivenhoe I don't think Brisbane would have seen a major river flood event in the period between 1974 and 2011 because there just simply now are too few set-ups and systems to deliver it. I think the data and incredible flood events of the 1800s and 1900s up to the 70s are very much a product of the past and with the evolving climate (along with the presence of the dams) the chances are just so much less now.

Top
#1485170 - 11/01/2019 22:17 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
ashestoashes Offline
Weather Freak

Registered: 22/10/2017
Posts: 739
Loc: Voyager Point (South West Sydn...
I think these pressure charts below show the state of the weather for you guys. Usually in December you would have dipping low pressure, but you guys had a ridge extending Inland. Sort of being surrounded by low pressure anomalies one to the South that was unusual.



Edited by ashestoashes (11/01/2019 22:18)

Top
#1485175 - 11/01/2019 23:08 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: ashestoashes]
Nature's Fury Offline
Weatherzone Addict

Registered: 29/11/2009
Posts: 2545
Loc: Brisbane Western Suburbs
Ashes can you provide a link for that? I'd like to check it out in the future.

Meanwhile in NSW they've had yet another day of severe storms:

Mt Gray (near Goulburn) recorded 38mm in 30 minutes from 1:25pm to 1:15pm.

Hail up to 4.5cm diameter was reported at Mt Victoria (Blue Mountains) about 1:50pm.

A gust of 107 km/h was recorded at Cobar Airport at 1:57pm.

A gust of 108 km/h was recorded at Cowra Airport at 4:14pm.

Hail of 4 cm diameter was reported at Yass in the early afternoon.

Hail up to golf ball size was reported at Holder and Duffy (in Canberra) around 3pm.

25mm of rain fell in 20 minutes at Weston Creek (Canberra) around 3pm.

Top
#1485179 - 12/01/2019 00:09 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
ashestoashes Offline
Weather Freak

Registered: 22/10/2017
Posts: 739
Loc: Voyager Point (South West Sydn...
NF below are the links. Anyways amazing turnaround for drought stricken NSW, storms hopefully others will see this kind of turnaround.
anomaly archive of pressure
Average MSLP according to annual and specific months.

Top
#1485183 - 12/01/2019 07:18 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
michaelmac50 Offline
Cloud Gazer

Registered: 11/10/2018
Posts: 13
Loc: Kilcoy, SEQ, QLD
Kilcoy...
Yesterday...18 degrees @ 5am
Today...17 degrees @ 5am
Loving these cool starts...
Shame it will probably warm up again...soon.

Top
#1485189 - 12/01/2019 08:47 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
retired weather man Offline
Meteorological Motor Mouth

Registered: 01/07/2007
Posts: 5161
Loc: Wynnum
Mega,

In regard to your question about dry periods. I grew up in Brisbane in the 50's and 60's. 1957-1962 and 1964-5 were very dry too in SEQ. Prayers were said in State Parliament in 1962 and 1964 to help break the drought.

There were a couple of short wet periods during those years, just like we see today, but overall very dry.

Top
#1485191 - 12/01/2019 09:13 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
crikey Offline
Weatherzone Addict

Registered: 01/02/2011
Posts: 3184
Loc: Tweed Heads
The tweed river flooded about 12 months ago and equalled the second highest flood event from 1974. The big floods here seem to be ex tropical cyclone remnants coupled with King tides.

The average mslp maps all show ridging in summer as a standard synoptic pattern.
select Dec, Jan ,Feb
http://www.bom.gov.au/jsp/ncc/climate_averages/mean-sealevel-pressure/index.jsp?period=jun

Maybe the unusual thing is the lack of breaks from low pressure fronts with a very zonal mid latitude.
-----
Great time lapse MEGA. Great find!! Love to see more of those. A picture says a thousand words
-------
Not everyone is getting dry weather from this stalled synoptic pattern.
The trough and stall line from the NW to the SE has just been incredible. Storms day after day


Edited by crikey (12/01/2019 09:15)
_________________________
http://weathercycles.wordpress.com/

Top
#1485192 - 12/01/2019 09:17 Re: SEQLD / NENSW Day to Day Weather - January to July 2019 [Re: Seabreeze]
retired weather man Offline
Meteorological Motor Mouth

Registered: 01/07/2007
Posts: 5161
Loc: Wynnum
As can be seen from this BoM data, Brisbane River floods were quite common from the time of settlement in the late 1830's till the end of the Century when the Federation Drought kicked in. After that period, Brisbane River floods have become less frequent.

This graph shows river heights at the City gauge near Petrie Bight and is only reliable up to the construction of the Wivenhoe Dam in the mid 70's after the 1974 flood. But even so the trend has been downwards since 1900.



Top
Page 8 of 138 < 1 2 ... 6 7 8 9 10 ... 137 138 >


Who's Online
1 registered (1 invisible), 35 Guests and 3 Spiders online.
Key: Admin, Global Mod, Mod
Today's Birthdays
No Birthdays
Forum Stats
29947 Members
32 Forums
24194 Topics
1529243 Posts

Max Online: 2985 @ 26/01/2019 12:05
Satellite Image