Topic: Darwin Storm events 2008/2009

[Michael Bath]

The NT BoM issued a STW for the storms last night at 8.30pm. It looks like it was cancelled 30 mins later.


SEVERE THUNDERSTORM WARNING
for Damaging Winds
For people in some areas within 60 km of Darwin.
Issued at 8:24 pm on Saturday 18 October 2008

At 08:20 pm, thunderstorms with the potential for damaging winds were observed on radar between Manton Dam and Middle Point moving towards the northwest.

The following areas may experience damaging wind gusts between 08:30 pm and 09:30 pm:

Manton Dam,
Acacia Hills,
Noonamah,
Fogg Dam,
Humpty Doo.

[Mike]

Indeed?    I saw the line of storms in the distance but honestly, I thought it was going to die a quick death once it hit the inner rural areas given the conditions, which it did eventually do.  I was watching the radar before i went to dinner break which showed a strong stumpy line and visually could only see the odd flash.  After an hour I returned to work to check the radar and it had dissipated quite badly.  It was holding a line up even just past Annaboroo.  Guess the SWW okay for the odd rural folk way out there - but it's not that populated !

There were quite heavy falls on the southern and western sides of Darwin in inland areas with those cells.  A very weak shelf appeared but I was out at the wharf taking photos of a visiting oil rig lit up - so that gives some indication of how lightning active/severe it was! 

I only knew of the SWW this morning after my daughter told me about it and then seeing it here.

[Harley Pearman]

Richary

I will add to Mikes comments here on storms. I lived in Darwin 1995 / 1996 and was up there again January 1999. The thunderstorms while impressive are very hard to predict. This time of year it is common to see a cumulus tower rise to great heights then drop a shower of rain and produce a few lightning flashes and the storm cell simply collapses. Then it is gone. I am still unsure as to how you chase these storms due to their short life span.

I simply went to a lookout somewhere and watched them and got many photographs that way.

I saw an entire wet season only because I lived there but Mike is right, there is no particular time when storms are most common.

As a rule of thumb and looking at the storm maps of Australia it is true that Darwin region averages some 80 to 90 thunderstorm days a year which is the highest in the country however there are some buts to this:-

a) There may be a storm in the proximity of Darwin on any day but it might not hit the city. It may remain in rural areas that you cannot get to it.

b) The storm may not move when it forms and so its life span can be very short.

Thus the number of thunderstorm hits on Darwin city is lower than what the thunderstorms maps actually show.

That is what I found when I was there.

December:

November and December seems to be the month of highest thunderstorm activity. Although December seems to show the spike in lightning activity. Peter Jarver in the 1980s found some statistics of lightning activity in Darwin (I assume from BOM) but Mike may be able to correct me if I am wrong here or if anything has changed:-

- 10,000 to 20,000 lightning flashes within an 80 km radius of Darwin during the month of December.
- 40,000 lightning flashes on average in the same area for a typical wet season.
- A thunderstorm can be in the vicinity of Darwin on any day during December.

With the average thunderstorm swelling to encompass 7,000 cubic km of sky.

That is not an enormous area if a storm cell towers 20 km.

December seems to be the best time for lightning just before the onset of the main wet season.

Then again. I was there in January 1999 and there were some terrific thunderstorms because there was a good break between monsoon bursts.

February and March is another good time. Called the build down. Mike could elaborate more on this.

There is a period called the build down. The "Knock em down" storms. Occurs after the main monsoon season has finished. There is an increase in thunderstorm activity again through March and into April. It is a time when storms knock down the "Speer grass". These storms can be gusty ones and the name implies the grass gets knocked down by the rain and wind.

Come April, the seasons revert over to the dry.

Thus Richary the best times would be late November to well into December and February / March but it can vary and surprises can and do occur as I saw in January 1999. Hope this helps.

Harley Pearman

[Richary]

Thanks guys. I doubt the budget will let me do it this season but useful to know for future planning. The frustration is arriving from having just bought the new camera and having no storms predicted to hit Sydney for the next week! Though it wasn't forecast we did just have a cell form and move west-north of my location but despite a few rumbles being heard there was nothing to see.

[Mike]

Harley is pretty well spot on with the exception of a couple of things.  Back in the 80's the storms were referred to as 'knock-off' storms as they ALWAYS came at 4:30pm.  Even Peter during the late 1990's noticed a marked decrease in the number of storms daily as he had chased in the early days.  I lived here back in 1985 for two years and the storms were just nuts each day.

Since being here 7 years now, it has changed dramatically with the impact of global warming or climate change or whatever they seem to call it.   Some years have been better than others, much like most places around the world.  Whilst the storms are single pulse types - they can be frequent in several areas and over time I've gotten a handle on which ones to go for simply through experience and observation and many busts!

October is atrociously haphazard for storms and is not renowned for many days, but BoM have confirmed that we have had 6.5 storm days which is over October's average and rainfall is over 40% the norm.  The squall lines that have come through have been the main rain producing systems.  Once they hit Darwin they stall somewhat and just dump everything over a wide area. The sea breeze flows inland at least 40km so it creates a blocking effect.

The annual thunderstorm days are taken over several years' averages - given the proximity and number of storms in any given area it's pretty accurate - Darwin 'city' may not get 90 thunderstorm days - but 'Darwin' as a generic term certainly does if it includes outer Darwin areas and rural.

The build up period we currently have is well documented for severe storms simply due to the sudden rate of instability induced into the region.  The build down - as Harley puts it ! - is in March to April - but we had Cyclone Monica CAT5 in April remember!  Every season is different. 

The best times are as Harley mentioned.  Look for monsoon troughs close to us near the coast but NOT on us - too much monsoonal rain comes with it.  Ocean borne tropical lows and heat lows with associated troughs from the Kimberley area are great storm producers for us.

I have a full list of what type of storms we had last year including dates, locations, severity and storm type which I will post. It's very in depth and will give everyone an overview of what we had, got and when!

[Mike]

Darwin storms Nov 8 update ...

Jeepers, lightning going nuts all over the NT but nothing here in Darwin!

Had a work mate who goes shooting out bush regularly and he was going down the track to Pine Creek, he rang me to ask if there was any chance of storms out there as he did not want to get caught in them...I was thinking, 'Mike don't give him uneducated nowcasts!'  I told him that you'll get storms but not till around 3pm so stay close to the main highway if you need an escape route.

Looking at the radar now it's safe to say my nowcast was pretty right after viewing the obs this morning...big numbers but a strongish cap which would burn off quickly given the extreme temps inland.  Some really lovely big fat towers with anvils over Labelle to the west again, it's the largest storm on the radar apart from Hector.  It's not close enough to get any decent nighttime lightning, but I reckon it will make an outstanding sunset storm photo, so I'm going down the road on the coast to get some nice pics.

 Hector is amazing today...3 big towers.  Started with the latter two dissipating quickly and the third really showing strength and outflow convection ahead produced some nice towers also.  Two big anvils formed on the front edge of the leading towers and were just wonderfully crisp.  I was going to take photos but thought not as I was heading back home in the opposite direction and running quickly out of open areas to get him in full view.

Several cells are popping up in inland areas to the E and SE now, which is textbook for their steering predicted tracks, so the forecast for late gusty storm may prove a safe bet.  It will take them about an hour or so to get here and depending on how the sea breeze interacts then it's a waiting game, but from what I can observe there's no shortage of large, fat storms in the outer inland areas.  Might have to go hunting wa-a-a-abbits....err....updrafts!

Darwin radar loop as at 6:03pm NT time  http://mirror.bom.gov.au/products/IDR632.loop.shtml

Will post something more significant and detailed as the night progresses.



 

[Mike]

Chase overview Sat 8 Nov

Viewing the sounding in the morning and plotting the obs during the day the bureau's predicted gusty storms were def on the cards.  The afternoon came along and there were several large cells developing to the SW of Darwin in Labelle, which is on the outskirts of Litchfield Nat park.  This is prime storm ground but a little too far out unless you're certain storms will head in that area.  I decided that the inland rural areas were the go for my chasing.  I headed down to a close location first up to get some arvo photos of a large cell during sunset.  I managed 3 nice lightning shots but the images had something on the lens so I have no posted them.  Hector over the Tiwi Islands was superb.  Just an immense beast and I have posted a nice sunset lit photo of the large anvil.

I headed out around 6:30 to the rural areas as there was considerable lightning and towers being illuminated.  The storms were forming a line which typified their organization through the wetlands zones but were frustratingly slow moving.  I got caught in four separate downpours after retreating from what would have been a 360 degree view of the open landscape, the rain just wrecked it.  Gusts were probably about 40-50kts given the amount of leaf and small branch debris scattered everywhere.

I got home around 10:30pm and did a quick check of the radar.  Unusually the front had weakened, but had looped anticlockwise around the eastern parts of Darwin and the storms reformed along the coast.  The skies had become clear and no wind or rain to be had - it was like a huge dry slot had pushed everything east!  These are the storms I like as there was calm conditions and you could see where they were due to moonlight.

Missed a couple of pulsing bolts, but am sort of satisfied with the pics I have posted.  Taken from around my area and rural, with sunset lit Hector.

...oh...there was a massive severe pulse which looked like an atomic explosion with a smooth hard anvil. I saw it but did not photograph it - I should have, as you don't see too many all alone in the rural area - it was unreal!.


---> Darwin radar loop



photos from last night..

[Michael Bath]

Thanks Mike - great reports of what has been going on. Nice to read as nothing happening over here !
You need to check your radar loop link.

MB

[Peter J]

Mike - these are great lightning pics!
In your opinion, when do you think the first NT cyclone might form this season?

Big Pete

[Mike]

Thanks MB.  Have fixed it - funny looking radar

Pete, I have no idea. When the monsoon trough appears it may give some indication but anytime from now till April.!  BoM were hinting before xmas, but it may be enforcing public awareness in case one comes.  Knowing where they form is just as difficult.  Once a low forms it's sort of easy to track its path to some degree.  But I'm as confident as the next person in reality and don't like forecasting cyclones in advance!

Have another chase report which I'll do today.  I've only just got home from 4 hours chasing widespread clean air storms.  So much to show and tell.  An outstanding night out.  It's now 5am and I really should get some sleep.  The photos were just brilliant - my photos have been disasters of late, but I've gone back to basics, used what I know and it paid off.

More soon.

[Carlos E]

I notice Darwin had some good activity on the radar when I woke up.

Great pictures earlier in the topic as well.

[Mike]

Storm photo op 10 November 2008

Not much had been happening during the day except for the usual larger storms well inland.  There was nothing during the night and I thought it was going to be another 'late storm' scenario.  We had finished work earlier than expected at midnight and checking the radar did not show anything at all.

Taking a work colleague home we were about 10 mins out of Darwin and I noticed a flicker of light from a cloud right next to us.  The moonlight helped the observations for this old bloke and yep, there was a skinny tower - yet tall - and it was firing up.  It must have been forming during my peak at the radar who knows!  It continued flickering which was great as I had about 10 minutes to drop my baggage off and then go after it.  I won't call it chasing simply because this thing was no less than 6km from my home,so to be fair it was a perfect photo opportunity.

I decided not to go into town because it was firing rapidly and did not want to waste time driving unnecessarily.  I located just around the corner to my home which offers excellent open views.  The storm had grown considerably and looking at the radar loop this morning it showed storms moving in from the coast and also toward the coast!

---> Darwin radar loop

I decided to go back to basics with my camera and shooting as I've been in a glut with getting decent shots.  I'm pretty pleased with finding my mojo again as far as that is concerned.

Here's some of the shots taken.  Settings: F9-10, ISO 100-200.  Exposure times all under 25 seconds.  Nabbed about 30 keepers but these are some of the prime ones. 

[vrondes]

Some classic bolts from the blue there Mike, certainly looks like some severe current in those clear air voltages from the anvil, especially the last frame , well done,
Cheers, Con.

[Mike]

Today is looking outstanding.  Text book instability with full CU's building, rumbles and well just everything.  Batteries are charged again!  The presence of that low inland and the trough sitting just below us sure makes for a complete mirror image of build-up storm scenarios.

[cloudfairy]

Great pics, Mike, as always     And I like your report.

I must confess, I'm jealous!!!!  And I hope I will get some good ones too.
Just five days left!