Storm Australian Severe Weather Forum

Severe Weather Discussion => Tropical Cyclones, Typhoons and Hurricanes Worldwide => Topic started by: Mike on 09 January 2007, 07:55:23 AM

Title: Monsoonal activity 2006/07 season
Post by: Mike on 09 January 2007, 07:55:23 AM
Our monsoon is due to arrive in Darwin and coastal areas on Thursday 11 Jan.  It's been building for the last two weeks and is almost upon us.  We've also got a weak 1006Hp low imbeded in it just to the N of the Tiwi Islands, but it's not expected to form into anything as such within the next three days at least. With the combination of the two it's been storm chase heaven - I just can't sleep!

We've had a superb buildup to the monsoon over the last week  Friday 5th through to Sunday 7 Jan 07 saw many decent HP storms roll through.  Significant rainfalls in most areas.  My home area was hit with two large HP storms within an hour and at a guess with 35-40knot winds accompanying both of them.

There are daily storms around the skyscape and generally coming in during the afternoon without fail to-date.

So looks like the Top End is at last 'going off', I'm particulary pleased as you would all imagine - the only frustrating thing is in which direction to go to get shots - but the city is still favoured!

 If none of the members have seen the skyscape with a monsoon on the horizon i'll get some shots and post them, quite a cool sight with grey-green skies with white immature Cb's in the foreground - worth photographing!

Regards, Mike.
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 10 January 2007, 07:18:30 AM
Jimmy, here;s your answer re monsoonal storms.

There are two regimes during the monsoon. (1) the monsoon trough is near Darwin then thunderstorms tend to be frequent, slow moving and can sometimes lead to flash flooding (warning current now)
(2) the monsoon trough is south of Darwin and Darwin is experiencing fresh to strong Nw winds thunderstorms will become in off the water, often in successive lines and can be associated with strong gusts, sometimes damaging.

The main differences with buildup thunderstorms tend to be: 

- generally (but not always) lower CAPEs often in the 1000s to 2000s rather than 3000 +j/kg.

- timing: often overnight and into the morning, rather than in the afternoon/evening.

- less electrically active, with just one or two claps of thunder rather than the buildup activity (sometimes there is no thunder at all IE deep showers rather than thunderstorms)

- direction of movement - come to Darwin off the water rather than inland.
- height: cloud tops tend to be lower than the buildup specimens.

I think that would cover it all.
Title: RE: Monsoonal activity 2006/07 season
Post by: Jimmy Deguara on 10 January 2007, 07:28:05 AM
Hi Mike,

Now that is interesting information given the specified differences. Personally, I didn't know that although I knew there were night and morning activity coming from the ocean and the storms that come in from the south or southeast. I take it this would result from the position of a surface low or monsoonal trough? Upper level winds woud need to be generally different to create the difference in movement.


Jimmy Deguara
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 10 January 2007, 09:25:13 AM
Indeed, Jimmy. Mid-level winds impact on our monsoon and tropical storms all the time.  Watching the storms today you can see the way they are coming in off the water - with the NW flow around that low to our NW, you can see the waterborne storms moving NE across the islands, but the other storms moving in from the NE.  It's weird to watch but interesting!

There is little or no lightning as i said, perhaps there's just too much moisture and cool air in and around the storms that inhibits it.

I always thought that upper level winds directed our cyclones, but it's the mid-levels that steer them from the East.  Having watched the monsoon troughs bobble up and down and watching the lows steer westward all the time, I've often asked why our cyclones end up in WA all the time.  It's not from a NW flow into the systems, but the steering winds at mid-levels from the east that push them NW

 There's still enough low level stuff to feed them - as with Monica last year was a good example - although her splatial size was mainly over land, she still had enough mass over the warm waters to have her retain her strength - and even now the met people are looking into that very thing.  Maintaining a CAT5 right up until her eye crossed the coast with such a  large percentage of her feeding 'off the land' so to speak.  It just didn't make sense at the time considering the models.

I think it's one of those areas that perhaps i'll look into more as far as monsoonal processes are concerned - 'tis certainly keeping me busy!
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 10 January 2007, 11:06:58 AM
Jimmy further to your questions - sorry i've misunderstood you and confused myself a tad :

Yes, the convection is directed by upper level winds - good indicator is wind at 700hPa/3km.

Also re surface low, yes, a surface low will be positioned within the monsoon trough being the lowest pressure in the linear area of low pressure.

Jeez sorry about that.   I believe i've amended my mistake!
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 12 January 2007, 05:18:43 AM
The monsoon is a bit lame at the moment i must say!  There have not been the constant squally showers that is normally experienced, but only the odd shower - light and heavy at times.  We had a few storms last night and this morning but there's too much daylight!  The forcast was for monsoonal showers/storms till Saturday, but now it's showers/storms.  The trough is at the base of the NT but will get pushed back up to us as that H in the bight moves east. The bureau says we should see the return of decent storms next week. :(

One consolation is that the newspaper here published three of my photographs with a half page story on the monsoon and subsequent weather.  Famous at last!
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 24 January 2007, 05:37:31 PM
For those who would like to know...our monsoon or lack of it appears to reforming over the coming week, so hopefully by friday next in early Feb we should see some organisation.  We're about 260mm below our average for January to date, thanks to that deep low that stole our weather!  But on the positive side at least WA, Alice and SA got something out of it.

Just general inland storms predicted for the remainder - one can only hope they reach the city!  Soundings average, CAPE good each day but that's expected although our winds have gone from NW to SE and NE, which is good for storm development in the arvos. Everything else not in favour for anything significant.

The monsoon only generated average rainfall around the place, nothing like persistant monsoonal showers as the norm of previous years, but there's plenty of time left for further activity.  The monsoon trough is above us, it just has to develop more and move further south - patience!
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 28 January 2007, 09:08:46 PM
well the rebirth of the monsoon is about to come again with the trough gathering good strength compared to last time around Jan 11 '07.  Flood advices have been posted on BoM and there's another weak low 1008hpa expected to be in the gulf on Tuesday.  The weather today was great - high rates of humidity and skies just ripe for storm formation, you didn't need sounding charts - the sky told it all!

By about 6pm things got well underway atmosphere wise and by 7:30pm there was a fair amount of electrical activity.  Unfortunately constant steady rain hampered any vantage point without getting wet - I ran out of time being at dinner at work (again) when things started to get exciting and missed the opportunity to get some really good CG branching over the harbour by about 8pm. 

Forcast is for showers and storms for the next week, so now that i've got a weeks respite from my night work i'll be able to chase a bit more.  My daugher is quite the avid chaser now with me and enjoys seeing the lightning, but gives me a hard time when i'm setting up the camera and missing the good CGs - always the critic!

This second rebirth of the monsoon looks like it will be a bit more substantial, so I think all up here that chase will be pretty chuffed - that's if we can get some shelter from the rain to get some decent shots!

Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 01 February 2007, 07:04:32 AM
Things cooking up here.  We've got a 1002 low in the gulf and now a 1002 low above us (both heading east) and both are expected to deepen by Friday 2 Feb '07.

Went chasing last night and was not disappointed in the action.  I must admit since chasing seriously in the last year or so and not taking much notice of what types of lightning were about but I saw my first Stattaco bolt on the way into town - awesome!

There were plenty of cells around the Islands and along the north coast and found a perfect spot to capture some great shots.  Spent about 2 hours photographing until it all went further north.

There's still plenty to come and 'hopefully' the lows will develop into cyclones and come back our way - the chasers in Qld and North Sydney should see some of the overflow from these systems as they develop with storm activity - good hunting!

Title: RE: Monsoonal activity 2006/07 season
Post by: tohnanon on 01 February 2007, 06:18:33 PM
My first post - Hello storm watchers.
I am doing time in Gove NT and have enjoyed what nature has offer me in cloud formation and storm activity. Today we have been under Cyclone watch as the low has deepen to 1001hpa, so i may experience my first Cyclone.
I have found this tropical weather quite comforting, like a warm hug, and forever changing, I tend to star into the clouds alot and have seen some quite amazing formation including a water funnel and many nuclear type mushroom formations, one that had a halo on its peak. Here are some amature photos. Thanks for the great info
Title: RE: Monsoonal activity 2006/07 season
Post by: Jimmy Deguara on 02 February 2007, 12:42:21 AM
Welcome tohnanon,

Did the mushroom cloud put out lightning at any point or was it attached to the rain band?


Jimmy Deguara
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 02 February 2007, 04:32:41 AM
Welcome too Tahnanon!  You will find as I have there are many experienced people on this forum and you'll be educated beyond belief - so ask away if you need to know anything!

Yes, Gove and Nhulunbuy see a lot of cyclone activity as the majority of the NTs systems form from the Gulf area.  The system is expected to be Cat2 by Friday/Sat and models track it heading SW - but as unpredictable as they are, anything can happen.  Far North Queensland looks like getting widespread rain from that system and the other low over Cape York.

For myself personally and others interested perhaps you could keep posting some information on the weather over the next day or so and describe what is happening with the cyclone in the area?

Great shot of the thunderstorm also - beautiful colouring and shape!

Title: RE: Monsoonal activity 2006/07 season
Post by: tohnanon on 02 February 2007, 06:11:18 PM
Well here it is a calm night in the sky, light rain occasional lightning in the distance and a balmy light breeze. But preperations on the ground is very busy, I am an active member on the radio station and we are putting out warnings and getting a 24 program ready in case things esculate. The community radio is a life line for communications to the public and we advise everyone to keep a radio and batteries on hand for updates and warning in case all else fails. So i was invovled in getting the generator prepared and at work we had to pack up all valueable equipment and cover other belongings in plastic. People here arent really in panic mode and alot say this is a safe area as we have had alot of close calls with Cyclone Monica and others. Ya never know and prevention is better than disaster. We have had a fair bit of rain but not as much as i would expect, coming in heavy but short downpours, with a uniform grey sky and not much wind. The mushroom cloud above was a morning storm from early last year and the lightning wasnt very visable but the distant thunder rumbled often. I do have 1 question regarding the cyclone - at what stage does a tropical low become catagorised as a cyclone?
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 03 February 2007, 04:44:39 AM
Hi John.

 Now there's something I didn't know re Cat1 hurricanes - are they classified differently in the US?  Are our Cat5 systems equal to their Cat1 hurricanes?  I thought the systems were the same just differentiated by location and description (title)?  So if they had they had hurricanes with winds of 35k or 55k what category would it be then?  What you say re this would mean theyr'e not classified except as depressions!

Title: RE: Monsoonal activity 2006/07 season
Post by: Michael Bath on 03 February 2007, 05:25:31 AM
Hi Mike and all - you can find some TC scale comparisons here:

regards, Michael

Title: RE: Monsoonal activity 2006/07 season
Post by: tohnanon on 03 February 2007, 06:34:08 AM
Ahh that makes sense Thanks for the reports.We have had max gust of 47klm and av. about 25klms here and its seems to be picking up today, even though the Low has gone past or atleast around. The BOM reports are saying at the center the wind is 65klms so this would explain why it is not a cyclone yet. The baro here is bouncing 995 and 997 humidity is 100%, air and water temp are fairly equal not too much rain although last night i thought the roof was going to collapse from heavy showers. These readings i get from a direct reading from a detailed weather station that has upto 1 minute data logging. Reading
Data From yesterday
Date 01/02/2007 this is 24hrs upto 09:00:00 AM
Maximum Air Temperature 31.38 DegC
Average Air Temperature 27.89 DegC
Minimum Air Temperature 25.53 DegC
Maximum T10m 30.4 DegC
Average T10m 27.85 DegC
Minimum T10m 25.46 DegC
Maximum Relative Humidity 83 %
Average Relative Humidity 73 %
Minimum Relative Humidity 60 %
Total Solar 17.194 MJ/m
Maximum Wind Speed 22.6 Kph
Average Wind Speed 9.5 Kph
Average Wind Direction 90 Deg

from today so far at upto 9am
Maximum Air Temperature 25.01 DegC
Average Air Temperature 24.79 DegC
Minimum Air Temperature 24.53 DegC
Maximum T10m 25.28 DegC
Average T10m 25.05 DegC
Minimum T10m 24.8 DegC
Maximum Relative Humidity 100 %
Average Relative Humidity 100 %
Minimum Relative Humidity 100 %
Total Solar 0.212 MJ/m
Maximum Wind Speed 32.7 Kph
Average Wind Speed 24.2 Kph
Average Wind Direction 256 Deg

Well here a little data from GOVE

Lets see what this storm does from here

Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 03 February 2007, 07:10:09 AM
You gotta love the humidity levels at 100%! Total saturation! The info handy, looks like landfall Saturday perhaps but is going away from you and heading to Port McCarthur and Borroloola - perhaps the courthouse will get trashed (void of people of course), it will save me some typing!

Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 06 February 2007, 04:53:47 AM
Well the monsoon rains finally got their act together over the last few days (Feb4 and 5 '07) The tropical low in the Gulf has knicked a lot of our weather - still getting the odd storm but rain wise, not much.  But over the last two days the winds have changed and the monsoon is lying across the Top End.  (The wind kite surfers were out in force during the weekend surfing - unusual but they take every opportunity they can when the winds pick up!)

The low had moved east towards  Boroloola but shifted a big U-turn and went east to Mornington Island, but is now turning W/NW.  She/he has been lingering in the southern coastal edge of the Gulf coast for a few days and is very erratic in movement.  Central pressure still largely unchanged at 998 - but the fold at the bureau are really just seeing what it will do in open water thus far.

We've had pretty much 'flogging' down type rain overnight with some big storms at around 10:30-11pm last night (4th)  I was at work (again) and saw this thing sillouhetted in the night sky against the moonlight - damn there were some fine CGs - by had no time to grab the camera for any length of time. Hate that!

Should be good for storms again tonight - depending on how many breaks there are between the monsoonal showers of course!

Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 21 February 2007, 02:05:36 PM
Monsoon update Feb 19 2007: Decided to leave this topic in the January spot since it's all relative to the monsoon...if that's okay JD :)

Significant storm activity to our north has resulted in the resurgence of the monsoon trough to our north.  The increased storm activity around darwin of late is also been triggered by it also - much to my glee.  Outstanding storms last night 19Feb with 4 big storms all going wild around Darwin City, rural and out to sea.  Much the same tonight as I speak as plenty of big storms coming through from the SE. 

Our CAPE yesterday was over 3400, LI's in the -6's, SWEAT over 400 and TT's at 45.  A little lower today by the sounding but the broad trough that is covering the NT and WA is helping bring a low pressure system closer to Darwin.

 If only the sounding for yesterday had wind shear it would have made for a truly memorable night and day - last wet season we had one day with these figures and with wind shear producing a water spout in the harbour (which i missed!) All of our winds today were from the NE in all levels - guess one can't have all the right conditions!

On the radar now there's two major  lines coming through, so time to go get some photos again!  Thunder pretty regular now!

Mike :)
Title: RE: Monsoonal activity 2006/07 season
Post by: Mike on 27 February 2007, 09:46:58 AM
here's some storm action from the weekend Friday 23Feb and Satdy 24th Feb.
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 01 March 2007, 02:01:42 PM
Well my last two attempts to post an update with photos didn't make it again - any ideas MB, can you see them?  Bet this one made it......>:(
Title: Re: Monsoonal activity 2006/07 season
Post by: Jimmy Deguara on 01 March 2007, 04:10:51 PM
Hi Mike,

Some mean looking storms in those pictures - particularly the one on the ocean! Nice pileus cap as well! (By the way I have seen several pictures on there so that you know).

Australia has been quite active over the past few weeks!


Jimmy Deguara
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 01 March 2007, 05:15:34 PM
Thanks Jimmy. Seems our little island continent has been busy weather wise! Lots of places getting some really good action.  My meteorologist mate in Oklahoma has got tornadoes forcast for Norman where he lives - he's staying home - NOT!

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 02 March 2007, 12:17:14 PM
* Tropical low in the Coral Sea with probability as rated HIGH for cyclone development for Friday, Sat and Sun 2- 4 March 2007.  Bureau reported that this system is on par to become a significant system rated as Cat3 or higher.  One to watch!  Tourists Islands may well be in its path once it develops!

* Second tropical low off NT eastern coast moving very, very slow - current hpa at 996 - expected to track east slowly before turning west back over its previous course toward Darwin and into the Timor Sea to our west by Monday perhaps.  Another one to watch!

Satpics look really cool from the Brissy website.

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 03 March 2007, 09:55:01 AM
Tropical low over NT....Well the weather in darwin this afternoon Frid 2 March certainly taken a turn for the worse!  The low at 9am was located 100km SE of Jabiru (270km to our south) and moving at 12kmh to the west with a central pressure of 998.  Since 12noon the low has made it's presence felt with increasingly strong winds, showers, rain, lightning flashes.

The lower level clouds are just racing through from the NE and rain bands are taking shape on observation as the low creaps past us overhead.  Skies are blue/grey with areas of medium rain, flashes of CC lightning, CGs - (there goes another one) and definately deteriorating as the afternoon progresses.....heaven!

If anyone living here who has not experienced a tropical low come cyclone wanted to know what it's like to experience an impending cyclone then this is it - albeit on a 'maturing and progressive scale'.

Just fascinates me to stand outside work and watch the rainbands and cloud bands race by towards what will become a significant system in the latter days to come.  It's like watching something unreal - definately will become wetter as the bands reach us more over the weekend.  Certainly get's my blood racing!!!! Sounding for today - beaut low level and mid level winds !!

* Another update as of 4pm NT time - we've been hammered by massive amounts of storms hidden within the dense cloud cover.  I've counted multiple CG strikes - both singular and combinations of 3 and 4 side-by-side every 3-4 seconds and no longer than 30 seconds between 'hits'.  My office has a harbour view and i'm witnessing just superb lightning strikes - just pulsing up to four times over the ocean within 100 metres of our office.  Warnings are out for locally destructive winds of 90-120kmh in the Darwin-Daly area as the low continues to cross our path and will be a cyclone by Satdy.

I have never witnessed so much lightning activity in one system - no wonder cyclones are so powerful - there's just SO much energy in these things.  If this continues - as i think it will - into the night, it will truly make for some awesome lightning photographs.

Will keep you all posted on developments of this deepening system.

I'm simply numb.

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 03 March 2007, 02:53:30 PM
Another update for you's all 7:30pm Darwin time 2 March.  we have a cyclone watch extending to tip of WA coast.  The low is centred just west of oenpelli and still moving slowly at 12kmh westward.  Jabiru had 311mm rain in 24 hours - an 80 year record.  Oenpeli had 200mm today - they're flooded in.  Substantial rain this evening with no let-up.  Drove around the coastal suburbs and everything is flooded -street wise - river systems are way up and the golf driving range, well that's now a lake!

We've still got severe weather warnings out with 90kmh winds on the coast.  Hopefully will get some pics for you all to view.

If anyone has got any questions re the low, feel free to ask!

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 04 March 2007, 09:39:13 AM
Captains log 3 March 2007 - tropical low still moving to our west and intensifying.  By the time it reaches the Timor Sea this arvo 'it' will be named and a Cat1-2 by Monday.  NT is still on a watch as the low progresses westward.  Oenpelli Community is now an ocean and they've had 800mm of rain in four days!  We've experienced ongoing hard rain for the last 24 hours with a brief lull until about 2pm NT time where it's flogging down again. Darwin and suburbs received over 1000 CG strikes per hour for a duration of 3 hours Friday 2 March.

No wonder I was most upset as I had left the camera at home  - never again!

Pics below are of just one of the rain bands within the low dumping vast amounts of rain and a couple of pics of  the palms bending with the 90kmh gusts that associated the low.

Mike (soggy but happy)

Title: Re: Monsoonal activity 2006/07 season
Post by: orage on 04 March 2007, 04:55:35 PM
It must be amazing to witness a TC live, Mike. I have not experienced one before being a New South Welshman (although I understand we can get them this far sout). I always get exited when a TC forms, but I am particularly exited about this one because it is within radar coverage. The Wyndham radar looks very nice. You can see the rain rotating around a central point just to the west of Peppimenari, off the coast. There is also a rainband that extends to the south wast (almost following the coast). I;m sorry I wasn't able to post any radar images, as I had technical difficulties. Does anyone else have these images? I will continue to watch eagerly.
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 05 March 2007, 06:35:55 AM
The low is now TC George and is off the NT coast still heading west.  Cat2 by this afternoon.  Yep, tis quite cool watching the bands flow through, most of them were fromt the NE inflow tail and quite bizzare to see lots of low level clouds streaking through with the more structured storms easing through - you can definitely see the difference in wind speeds at lower and middle levels.

 The photos don't really do the system justice as it's always raining!  The photos above were taken at Nightcliff beach and the tide was WAY out - would have been better if the tide was in - huge swells.  Our heavy rain periods will ease a tad by tomorrow (Monday) and we should see the return of storm activity associated with the remnants as we'll finally get some sunshine to heat up the place - have not seen the sun in over a week.

 I'm still in mourning for forgetting my camera on Friday previous when the low was at its most active as it strengthened over us - everyone is telling me how they got supurb shots of the CGs - (2000 strikes for the 3 hours) you think i'm not upset!!!!

Thanks to Michael Bath for posting the pics, much appreciated.

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 06 March 2007, 04:58:41 AM
Here's a radar image of the line of severe storms that dumped 2000 CGs over Darwin and surrounds on Friday 2March 07. The system travelled from the NE then NW.

Am finding out from the Met office some technical details re the system, as to why it was so 'charged', what atmospheric conditions resulted in the storm being so violent etc - will keep you posted.

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 07 March 2007, 04:35:26 AM
Some pics of the Jabiru floods the other day.  They copped over 300mm and the rivers were up, up, up!  Check out the feral pig on the bridge! (shotgun anyone?).

Edit: Source of pictures unknown.
Title: Re: Monsoonal activity 2006/07 season
Post by: Jimmy Deguara on 07 March 2007, 11:01:04 AM
Hi Mike,

Gee it is good to see northern Australia back to normal - late season though! We are finally getting the moisture.

Did you take those pics yourself?

Not even a flood could destroy a pest animal!


Jimmy Deguara
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 07 March 2007, 11:30:16 AM
Ha!  Right on the money re the pig! They look nice and cute when young but they still get run over and shot at. (not by me!) Nope, can't claim honours for the pics - i'd still be stranded you see....lots of people claiming it was 'my brother' who took the pics, so no, i do not know who took them.

 The rivers have subsided a tad since then, they had crocs and all sorts of things stuck on bridges (true!).  We're back in the 'dry' stage between monsoon troughs, so now i get to have the storms out again in the arvo's.

Our rainfall total is up to par now , we started off really 'dry' but all this rain has topped things up.  That TC George off WA looks to go to CAT5, certainly a decent system after all.
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 08 March 2007, 07:26:08 AM
Here's some more photos of the South Alligator, West Alligator and Adelaide River flooding due to that Low - now TC George.  As you can see this area is very low lying and when you get an average of 1000mm in a catchment area, the water has to go somewhere!  The road damage is equally impressive - all that just from water flowing constantly over the bridge.


Edit: Source of pictures unknown.
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 13 March 2007, 04:44:30 AM
Some storm action that we've had of late.  Some nice big storms have come through, These two shots taken Satdy arvo before work as it moved W to E.  We've had some really nice severe storms with huge amounts of lightning with them - strong winds, just flash flooding type rains.

My daughter caught a line of storms coming in from the South on the radar last night, but the closer they got to us the more they peterred out.  We chased for about an hour doing one large loop around the storms, but as would have it, rain eventually overtook us no matter which way we headed.  So we ended up home watching some storm chase DVDs from a fellow forum member - she was rapted with that!

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 14 March 2007, 07:47:11 AM
Here's some info for those that want to know how our weather works during the monsoon and when the 'active' period returns.  i posed the question re tropical lows and the 'dry' period between monsoon troughs and what time period lapsed between monsoon events here:

(Thanks to severe weather meteorologist Michael Foley for this info.)

'If there are no lows/cyclones in the monsoon trough, weather activity tends to be distributed along the length of the trough; when a low or cyclone develops, the activity tends to "clump" around these focal points, with less weather activity in between; therefore if it is a situation where there has been a depression/TC which has moved away from the NT, we will then be in the less active part of the trough.  The trough may become more active again when the system has moved far enough away or dissipated.  Another thing which will renew activity in the trough is a renewed surge of the monsoon northwesterlies to the north of the trough; this is often correlated with the arrival of a new active phase of the Madden-Julian Oscillation which circles the globe every 30 to 60 days.

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 15 March 2007, 07:00:37 AM
Here's some past photos I thought I'd post since I have nothing better to do....I especially like my bubbling towers with the rain and lightning above them!

Title: Re: Monsoonal activity 2006/07 season
Post by: Jimmy Deguara on 15 March 2007, 12:15:39 PM

Nice anvil crawler activity - were those of a complex of thunderstorms passing over during the night?


Jimmy Deguara
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 15 March 2007, 12:28:31 PM
Absolutely, Jimmy! 

The pic with a lot of contrast and depth of trees, rain, lightning and the towers bubbling away was a very long line of storms that hung around for about 2 hours.  That night I obtained about 125 photos and dare i say it - got bored!  I thought they were multicells as there were anvils aloft not attached to those bubbling towers below as in the pic and those lower storms were feeding the larger cells.

There was no lightning activity from these smaller towers and most of the crawlers were aloft higher up.   There was so much electrical activity that night, it was just superb to just watch it. 

Have included some more just for the hell of it...

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 27 March 2007, 06:12:05 AM
At last some storms!  Nice cell across the harbour so during the tea break at my second job i whipped out the camera.  Cell lasted for over an hour so presuming it had decent updraft to assist it.  Was the only storm in the area and I've been starved of storms for two weeks!  Here's some happy snaps - made my week!  Would have posted more but files too big.  They don't show major CGs as they were on the other side of the harbour which my view was being obscured - but you get what you get and got some nice panoramic shots with crawlers up the top.

Title: Re: Monsoonal activity 2006/07 season/March-April
Post by: Mike on 31 March 2007, 04:34:08 PM
Well news is if the monsoon does not return by mid-April that's it for another storm season here in Darwin :(

Next week we'll have the dreaded easterlies dominating and that only means one thing - no weather!  Sunday and Monday may be it for storms.  Had some nice storms around tonight and got a great stattaco about 2km from me.  was just about to put the camera away and had second thoughts and one more go - a voila! 

Hope you guys enjoyed the updates from up here....certainly enjoyed posting them for you.

Title: Re: Monsoonal activity 2006/07 season
Post by: Michael Bath on 01 April 2007, 08:38:38 AM
What a nice way to end the season with that CG !   Hopefully there will still be some weather around for a little longer.

regards, Michael
Title: Re: Monsoonal activity 2006/07 season
Post by: Jimmy Deguara on 01 April 2007, 09:03:31 AM

Somehow in the initial check, I had not ovbserved that lightning bolt. Quite a tall staccato!


Jimmy Deguara
Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 01 April 2007, 10:56:51 AM
Thanks Mike B for posting the pic - blasted computers!

 The storm was producing a fair bit of sheet rubbish and I just gave up in the end and as i said I felt the change of wind and thought...mmmm maybe one more go.  As soon as i set the camera up and opened the shutter this thing blasted in front of me - I was so inwardly overjoyed i think i pee'd myself! 

I keep looking at it and noticing that it went from the cloud right to the ground this time! Oh man, i just love it when you get a reward like this!

Bit of storm activity around this arvo - definitely humid and hot - but will go out anyway and try my luck later when it's dark.  I'm taking every opportunity to get something before the wet goes dry - Aaaargh!

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 04 April 2007, 03:36:16 AM
Re March 1 thunderstorm/supercell event for pre TC George.

Finally got some info from contact at the Met office here re the deepening low that passed us by this day.  I'll copy type it word for word.  Some interesting comments to say the least!  Thanks to Greg Browning at the Severe Weather Section, Darwin Met Office.

"Ive also had a quick revisit of the !st March event and the later sounding shows no appreciable difference to the morning trace, if anything there is a bit more warming at 11Z.

The morning's sounding though gave an indication for all the ingredients needed to generate the kind of storms that could produce that amount of lighting you witnessed (and I enjoyed!).  Analysis yielded CAPE over 4000j/kg, LI of -6.9C, mid/low Level shear (1000 to 10,000ft) of 147/67, steering wind of 40+ knots etc.  As one Paul Keating would have said...those are beautiful numbers!

On top of this the main line of storms came through that night was associated with the outer convective rainbands of pre TC George and so extra vorticity and convergence also added to the mix, recall this was the environment that produced the high F2 tornado in Kakadu NP.

The sounding also showed some low level dry are due to sub-FZL evaporation of the considerablerain falling at thetime - which likely contributed to some explosive updrafts after the LL environment was eventually modified to the requisite degree.

So you had major instability contributing to the explosive updrafts along a favoured convergence line, shear and steering winds conductive to extensive and continued propagation along a wide swath and for a significant period of time. There were numerous strong cells embedded in the main rainband and their conmined effect was the almost continuous lightning that you saw.

I also commented to him that thankfully I have been studying the last 6 months and knew what he was talking about, phew!

Title: Re: Monsoonal activity 2006/07 season
Post by: Mike on 05 April 2007, 04:37:27 AM
Still some storms around late at night and early morning.  Got these shots on the way home from my night job at 1:30am and mozzies taking a liking to me - but not to be deterred!!!

We've been getting one large cell each night come through from way out SE so it's quite nice to have a full moon and stars with a single large storm being active. 

This storm was quite active and produced some great CGs.  It was away from me and quite frankly I think access to it might have been difficult where it was!