The Bureau of Meteorology has issued a flood watch for the Hawkesbury Nepean River System with probable flooding 28th February to 1st March 2013 period. With Warragamba Dam at capacity water has been released but any further rain in the catchment can increase the likelihood of further flows and flooding in the Hawkesbury Nepean River Region.
Gympie is experiencing a flood peak near 19metres emailing it the fourth flood in 12 months. This is devastating given it is still recovering from the same floods spawndebt the ex-tropical cyclone one month ago.
A number of tornadoes have been confirmed by the BoM:
http://www.bordermail.com.au/story/1329032/video-gallery-experts-confirm-family-of-tornadoes/?cs=2452
Tropical Cyclone Rusty is apparently set to intensify to a Category 4 cyclone as it heads for the Port Headland. Just another disaster in the making if it hits head on!
A red alert is already in effect for the region to be impacted.
Below is a beautiful LP non-severe storm slightly earlier that approached Castle Hill
I thought this particular storm for me personally exhibited clear rotation visually and is backed up on the video! Simply beautiful and I guess I got lucky for a change! The framing and direction could not be much more perfect than this!
This storm developed south of Appin before the storm developed near Blacktown. Finding a position was near impossible and some of the features I missed including inflow bands and the base is a pity. Nevertheless, the storm intensified and eventually put out a few bolts.
You can see in the second image that the base was rather interesting and seemed to be on a triple point. The base was lower than the typical bases surrounding the storm. Once the storm collapsed after probably an hour, I aimed for the storms now back-building to just north of Camden. I decided against this and chased the other boundaries and associated storms back-building south of Picton. It was not long that all storms collapsed and I called it a day.
There were some nice cells around Sydney today and this afternoon saw a pair of thunderstorms cross the Western Suburbs from North to South. The first cell produced some spectacular clear air lightning bolts which struck many kilometers ahead of the storm. It also produced an amazing high contrast hail/rain shaft, the best I have ever seen.
Another storm developed north of Richmond near Colo and followed the first storm into the Sydney basin, this time further west. I set up at Orchard Hills and got some time-lapse of this cell which also produced some spectacular lightning.
Flood watches have been issued for the NSW coastline with flooding warning evacuations on the north coastal regions.
As you can see from the radar tonight, lightning and widespread heavy rainfall is approaching the regions of the lower Hunter Valley and Sydney regions. Rainfall totals exceeding 100mm can be expected based on the Bureau models nearer the Blue Mountains but even perhaps Western Sydney may receive higher totals.
The north coast, particularly the region adn around Grafton and Coffs Harbour bracing themselves for flooding and strong winds early this weekend with falls of up to 300mm. As the low nears the coastline, strong winds will cause concerns.
20th February 2005 Giant hail smashed my windscreen perhaps upt to 4 inch in diameter! %%%Negative tilt trough%%% with destabilisation at the time of the event – this was the second of two major supercells although I suspect this one was more potent! I measured 8.3cm hail and I did not look for too long as I was getting too wet. The most interesting thing apart from the hail was whilst being hammered by base ball sized hail, I passed under the overhand for about 30 or so seconds, no hail fell and then bang! The giant stuff!
The Bureau this morning issues warnings for strong winds as the threat for waterspouts occurred off the Sydney and northern beaches coastline. Some large cumulonimbus with showers were spawning these waterspouts likely as a result of cold air aloft and warm seas surface temperatures.
After a resfreshed warning for a continued threat of strong winds, the warning has been cancelled by midday.
A severe thunderstorm hit Penrith this afternoon bringing copious amounts of hail to at least 2cm.
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The GFS model is showing a significant east coast low affecting Surfers to Sydney in the next few days. I’d say with the presence of a strong cold pool aloft this event is probably inevitable. The only question is how strong and where will be affected the worse.
Test Post from Storms - Extreme Storm Discussion http://www.extremestorms.com.au
