Severe Tropical Cyclone Hamish

[Somerset Squall]

Invest 98P has become sufficiently organised to be upgraded to a tropical cyclone, named Hamish. Intensity is at 35kts, and Hamish has some good convection persisting over the centre as well as some excellent banding features. Hamish is expected to drift southwards along the western periphery of a subtropical steering ridge to the east, and intensify in a low shear, warm sea, good outflow environment. BOM are predicting it to reach cat 2 on the Aus scale, which equates to minimal cat 1 on the SS scale, in about 48hrs time. Hamish is expected to remain offshore but only a slight deviation from track to the west would cause Hamish to make landfall. Communities from Cairns southwards look at most risk from landfall from Hamish, but most of the east coast of Queensland are at risk of substantial rainfall from this system.

Edited March 5, 2009 by Somerset Squall

[Somerset Squall]

Track from JTWC:

Interesting to note that JTWC predict continued southward motion until a final landfall just east of Townsville, whereas BOM are now forecasting a southeastward turn in about 48hrs time meaning it will miss direct landfall. We'llhave to wait and see who is correct. Hamish has the potential to become a dangerous cyclone over the coming days so it needs to be closely watched.

Edited March 5, 2009 by Somerset Squall

[Somerset Squall]

Hamish is a rapidly intensifying storm. Intensity has increased to 50kts. Banding continues to wrap well into the strong circulation, which has a central dense overcast feature forming. With continued low shear, warm sea temps and good outflow, Hamish should continue to strengthen. BOM predicts a 75kt peak before shear possibly increases on the southward track beyond 48hrs. Hamish has plenty of time to get perhaps a touch stronger than this over the next couple days. We shall see.

[J07]

Few hours old IR image, with forecast track maps from the models and JTWC (which is in white). From CIMSS.

Also attached is the latest BOM track. Still going for good development, but no landfall as yet.

And results of their Dvorak analysis

Dvorak Intensity Code: T3.5/3.5/D1.5/24HRS

REMARKS:

Descending QuikScat pass shows 35 to 40 knot winds in three quadrants. Deep

convection wraps 0.65 on log10 spiral. DT is 3.5 with addition of 0.5 for a

white band. MET supports. System is expected to continue to intensify under weak

shear.

[Somerset Squall]

An eye has appeared in satellite imagery and Hamish is now a 65kt, cat 1 (ss scale) cyclone. Rapid intensification continues, as shear remains low, waters warm and outflow excellent. Tracks have shifted slightly westward, landfall is predicted now to occur, between Bowen and Hayman Island. It's important not to focus on direct landfall as track can change and dangerous winds and rain extend out from the centre. JTWC expect a peak of 90kts prior to landfall. Dangerous storm this one.

[Things]

An eye has appeared in satellite imagery and Hamish is now a 65kt, cat 1 (ss scale) cyclone. Rapid intensification continues, as shear remains low, waters warm and outflow excellent. Tracks have shifted slightly westward, landfall is predicted now to occur, between Bowen and Hayman Island. It's important not to focus on direct landfall as track can change and dangerous winds and rain extend out from the centre. JTWC expect a peak of 90kts prior to landfall. Dangerous storm this one.

Been watchin this since day 1, and only just realized we (Cairns) are now within the strong gale force wind boundary, forecast for around 1pm Saturday. Getting ready for this one now

[Somerset Squall]

Indeed Things, be prepared for a bumpy ride. And of course, you must be prepared for a westward deviation in track, the difference between a gale and a hurricane force wind!

There is no stopping Hamish. The system has been upgraded to a severe tropical cyclone and intensity has bombed to 85kts, and pressure down to 959mb, making Hamish a cat 2 on the SS scale. As I said earlier, I thought the intensity forecasts were perhaps a little conservative, and it's possible the new forecast peak of 100kts by the JTWC may be. Hamish has a solid central dense overcast feature with a well defined eye. The environment will remain favourable for the next 36hrs, and continued rapid intensification is possible, maybe even likely. In around 48hrs, Hamish should begin to weaken due to land interaction and increasing shear. It's pointless trying to pinpoint a landfall location (if there is one, latest JTWC have Hamish missing land, just!), the whole of the east coast of Queensland, south of Cairns are ate risk of flooding and wind damage over the next few days.

Edited March 6, 2009 by Somerset Squall

[J07]

Dvorak Intensity Code: T5.0/5.0/D1.5/24HRS

REMARKS:

Eye pattern with LG surrounds and 0 eye adjustment. DT is 5.0. MET is 5.0. DT

used as final T. SSE movement expected to continue with mid level ridge to E and

trough over the Australian continent dominant steering mechanisms.

[Somerset Squall]

I would be quite worried if I lived anywhere Mackay southwards looking at that map!

The eye is clearing out really well on satellite imagery. Soon to be a cat 3 on the SS scale I reckon. What a beast!

[Somerset Squall]

Hamish remains an impressive storm. Intensity is now at 90kts and the eye remains well defined and embedded within the central dense overcast feature. The south-southeastward track continues. This will bring Hamish very close to land after 24hrs, where it will bring damaging winds and torrential rains. At the same time, it will cause some weakening of Hamish, but not before the cyclone pehaps gains cat 3 status on the SS scale later today.

Edited March 7, 2009 by Somerset Squall

[bazookabob]

I think I better stock up on Bundaberg Rum before the factory blows away! Impressive storm this, especially seen as at the start of this week the BOM were calling for not much more than a wet tropical low to bring heavy rain to TNQ. Still not quite up to legendary Larry statud, which almost blew me away!

bb

[Things]

Still not quite up to legendary Larry statud, which almost blew me away!

bb

Wouldn't call that yet, BoM has forecast it to hit category 5 by 7am tommorow (Sunday) :o

This is one heck of a cyclone, now i'm glad it has passed me! :o

[Things]

Wouldn't call that yet, BoM has forecast it to hit category 5 by 7am tommorow (Sunday) :o

This is one heck of a cyclone, now i'm glad it has passed me! :o

Well, it's now officially upgraded to category 5 :o

295km/h gusts near centre!

I'm sure NO ONE wants to be hit directly by this thing! :o

[BarnetBlizzard]

Well, it's now officially upgraded to category 5 :o

295km/h gusts near centre!

I'm sure NO ONE wants to be hit directly by this thing! :o

Good luck Hervey bay.

[bazookabob]

Indeed I was horribly wrong I'm afraid. The one straw of hope to clutch at for the central coast is that if its anything like Larry, the very worst of the winds will be on the right side of the track ie, the east out at sea- of course, its hardly going to be a pleasant tropical day on the coast and I wouldn't want to be sailing the Whitsundays this weekend! Would be good to see some videos of this as there weren't very many good ones of Larry that I could find, and the one I had was on the camera that got stolen!

p.s 295kph gusts? Ouch!

bb

[Things]

Indeed I was horribly wrong I'm afraid. The one straw of hope to clutch at for the central coast is that if its anything like Larry, the very worst of the winds will be on the right side of the track ie, the east out at sea- of course, its hardly going to be a pleasant tropical day on the coast and I wouldn't want to be sailing the Whitsundays this weekend! Would be good to see some videos of this as there weren't very many good ones of Larry that I could find, and the one I had was on the camera that got stolen!

p.s 295kph gusts? Ouch!

bb

Going by the wind map it appears most of the wind is out on the sea side of the cyclone. There is about 10 video's of hamish on youtube right now, and there are 1-2 people updating every few hours on it. I am going to be following along, untill they loose power I guess

These guys for example, just behind Hayman Island

[bazookabob]

Cheers things... just another request of you- I've been trying to find a link where I can listen to a local radio station online from say Mackay or Airlie Beach but have had no joy... I don't suppose you or anyone else on here has been able to find one because I think it does give a new and interesting perspective on the situation! Cheers,

bb

[Things]

Cheers things... just another request of you- I've been trying to find a link where I can listen to a local radio station online from say Mackay or Airlie Beach but have had no joy... I don't suppose you or anyone else on here has been able to find one because I think it does give a new and interesting perspective on the situation! Cheers,

bb

Been searching for a little while, I can't seem to find any internet radio streams. I guess our best bet would be to keep an eye on the youtube updates. Maybe more people will start recording once it gets closer, I'm sure there's alot of people that want to see what this cyclone does, including me!

[Cookie]

stay Safe

Storm Alert issued at 7 Mar, 2009 0:00 GMT

Tropical Cyclone HAMISH is forecast to strike land to the following likelihood(s) at the given lead time(s):

Red Alert Country(s) or Province(s)

Australia

probability for CAT 1 or above is 35% in about 24 hours

probability for TS is 75% in about 24 hours

Red Alert City(s) and Town(s)

Rockhampton (23.4 S, 150.5 E)

probability for CAT 1 or above is 35% in about 48 hours

probability for TS is 55% in about 48 hours

Yellow Alert City(s) and Town(s)

Bowen (20.0 S, 148.2 E)

probability for TS is 60% in about 24 hours

Mackay (21.3 S, 149.1 E)

probability for CAT 1 or above is 25% in about 36 hours

probability for TS is 60% in about 36 hours

St. Lawrence (22.3 S, 149.5 E)

probability for CAT 1 or above is 25% in about 48 hours

probability for TS is 55% in about 36 hours

Gladstone (23.9 S, 151.2 E)

probability for CAT 1 or above is 30% in about 48 hours

probability for TS is 55% in about 48 hours

Green Alert City(s) and Town(s)

Bundaberg (24.9 S, 152.3 E)

probability for TS is 35% in about 48 hours

Note that

Red Alert (Severe) is CAT 1 or above to between 31% and 100% probability.

Yellow Alert (Elevated) is CAT 1 or above to between 10% and 30% probability, or TS to above 50% probability.

Green Alert (Low) is TS to between 31% and 50% probability.

CAT 1 means Tropical Cyclone strength winds of at least 74 mph, 119 km/h or 64 knots 1-min sustained.

TS means Tropical Storm strength winds of at least 39 mph, 63 km/h or 34 knots 1-min sustained.

[kold weather]

Still looks mighty powerful at the moment, small eye with a really condense inner core it seems, certainly does look a beast thats for sure, estimated pressure at 927mbs but I strongly suspect pressure could be easily another 10-15mbs lower then that at the moment.

Latest estimate:

07/1430 UTC 18.9S 149.5E T7.0/7.0 HAMISH

So certainly is a very powerful cyclone!

I expect its going to be a wait and see thing with regards to how long Hamish holds onto this strength but for the time being got to be around the 135kts mark judging from the estimates.

[Somerset Squall]

Well, wasn't expecting Hamish to be quite this strong when I checked in this evening. JTWC report sustained winds of 130kts, high end cat 4 on the SS scale, the system has quite literally bombed! Small shot at cat 5 on the SS scale before land interaction may hinder further development. As I'm sure you all know, it cannot be stressed enough how dangerous this storm is. Best of luck to everyone out there, stay safe.

Latest satellite imagery shows that Hamish has developed a pinhole eye, a sure sign of a very intense system:

[J07]

If it gets to T7.0 then that would be a Cat 5 on the SS scale I think....

(Last I saw they were calling it a 6.5)

[J07]

The latest BOM bureau gives it a dvorak t number of 6.0, and a category 4 on the Australian system.

Dvorak Intensity Code: T6.0/6.0/0.0/24HRS

Pressure of outermost isobar: 1002 hPa

Radius of outermost closed isobar: 100 nm [185 km]

Storm Depth: Deep

FORECAST DATA

Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure

[uTC] : degrees : nm [km]: knots[km/h]: hPa

+12: 08/1800: 21.8S 151.7E: 045 [085]: 090 [165]: 950

+24: 09/0600: 22.5S 152.7E: 075 [140]: 090 [165]: 950

+36: 09/1800: 23.4S 153.6E: 110 [200]: 085 [155]: 952

+48: 10/0600: 24.0S 153.5E: 140 [260]: 085 [155]: 951

+60: 10/1800: 24.2S 153.0E: 190 [345]: 080 [150]: 955

+72: 11/0600: 24.5S 152.6E: 235 [435]: 075 [140]: 965

REMARKS:

Final T based on DT with Black surround and Off White eye based on EIR.

Southeast movement expected to continue for next 48 hours.

[Cookie]

an old image but I think its a good one!

latest track

new update

Very Intense TC HAMISH is forecast to strike land to the following likelihood(s) at the given lead time(s):

Red Alert Country(s) or Province(s)

Australia

probability for CAT 1 or above is 70% in about 24 hours

probability for TS is 95% currently

Red Alert City(s) and Town(s)

Bundaberg (24.9 S, 152.3 E)

probability for CAT 1 or above is 55% in about 36 hours

probability for TS is 65% in about 24 hours

Gladstone (23.9 S, 151.2 E)

probability for CAT 1 or above is 35% in about 24 hours

probability for TS is 80% in about 24 hours

Yellow Alert City(s) and Town(s)

Mackay (21.3 S, 149.1 E)

probability for TS is 85% within 12 hours

Rockhampton (23.4 S, 150.5 E)

probability for CAT 1 or above is 15% in about 24 hours

probability for TS is 80% in about 24 hours

St. Lawrence (22.3 S, 149.5 E)

probability for TS is 75% within 12 hours

Maryborough (25.5 S, 152.5 E)

probability for TS is 60% in about 36 hours

Bowen (20.0 S, 148.2 E)

probability for TS is 55% currently

Coory (26.7 S, 153.0 E)

probability for CAT 1 or above is 15% in about 48 hours

probability for TS is 45% in about 48 hours

Green Alert City(s) and Town(s)

Brisbane (27.5 S, 153.0 E)

probability for TS is 35% in about 48 hours

Note that

Red Alert (Severe) is CAT 1 or above to between 31% and 100% probability.

Yellow Alert (Elevated) is CAT 1 or above to between 10% and 30% probability, or TS to above 50% probability.

Green Alert (Low) is TS to between 31% and 50% probability.

CAT 1 means Tropical Cyclone strength winds of at least 74 mph, 119 km/h or 64 knots 1-min sustained.

TS means Tropical Storm strength winds of at least 39 mph, 63 km/h or 34 knots 1-min sustained.

Edited March 8, 2009 by cookie

[Somerset Squall]

Nice image Cookie. This certainly has been a beauty to look at on satellite imagery.

Hamish has weakened slightly this morning, and 1 minute sustained winds have dropped to 125kts. Of course, Hamish is still a very powerful system with a very strong core and a small, well defined eye. JTWC and BOM are now in disagreement about what will ahppen next with Hamish. JTWC forecast Hamish to continue to weaken but to remain a CAT 3 on the SS scale for the next 48hrs as they are no longer forecasting landfall- instead they are calling Hamish to bend southeastwards and miss land- which is why they are forecasting the cyclone to remain intense. BOM however, are predicting a southwestwards turn back towards Hervey Bay in 48hrs, which will cause Hamish to make landfall just beyond that which is also why they forecast Hamish to be weaker in this timeframe to account for land interaction. Both JTWC and BOM forecast Hamish to at least get very near to Hervey Bay, so either way it's not a great forecast for the area, but it'll be interesting to see who's right later down the line. Even if Hamish misses a landfall, he will still weaken as shear is expected to increase and there would still be some land interaction which may also hinder the storm. The amount of weakening largely depends on whether Hamish goes southeastwards, or indeed dives southwestwards. One to watch.

News link: http://news.ninemsn.com.au/national/768302...d-to-category-3

Edited March 8, 2009 by Somerset Squall