Tropical Cyclone Oma

[Cyclone Tracy]

The BoM cone of uncertainty taking the EC ensemble as its base. Curve going the other direction to the JTWC map

[Blowy]

Thanks for the regular insights CT. By crikey there are a few (all) fruit growers here breathing a huge sigh of relief now, that thing is seriously 'plus size' and not what we need anytime soon. Some gentle 'tailings' will be appreciated however.

[Cyclone Tracy]

Oma is wobbling SW at around 5 knots and took a beating last night with dry air again getting into her structure. She is a asymmetrical cat 2 at 974 hPa, 55 knots. The size of her eye over the last 48 hours has most likely caused the dry air intrusions, as wind shear and the sea surface have been quite favourable. This morning her low level circulation centre has become much smaller given her another chance to rebuild an eyewall if she can cough out the dry air.

[Cyclone Tracy]

Interestingly only the GFS 18z and UK 12z have the current location on Oma correct (1pm NZT). EC 18z, Access R 18Z, New GFS 18Z are 50 to 100km out to the north.

GFS has an incredible scenario on the 18z run which defies all other models beyond 120 hours with Oma doing a U turn in the Coral sea and heading back south down the Qld coast. EC and the UK are going in different directions within 48 hours. I’ve never seen such differences between the main global models and their ensembles on a run to run basis over such a long period of time.

[Cyclone Tracy]

Oma has passed over the 160E line and becomes the BoMs responsibility. BoM's first official advice and have issued a TC watch on SE Queensland and far NE NSW. The cone of uncertainty has a large bulge within the next 24 hours due to ensemble disagreement on the turn. She should bounce off the strengthening ridge but I wonder what unknown trick Oma has up her sleeve next

[Cyclone Tracy]

As suspected and taking into account Oma's S wobble, the BoM's first track map which seems to be based on EC and Access R is out by about 50km to the north. GFS and UK right on the money.

Oma a Cat 2 around 50 knots, 980 hPa looking a little healthier with convection around a weak inner eyewall. Cat Island ob is gusting to 70km/h and has dropped into the 990's pressure range. Quite breezy now between the Gold and Sunshine coast as well.

Many eyes in OZ will be watching the 00Z run closely I would assume

[Cyclone Tracy]

TC Oma is a shadow of her former self with some shredding from westerly shear and now is a Cat 1. She is about to be bounced back towards the Coral sea by the strengthening ridge. BoM has dropped its cyclone warning for SE Queensland.

EC picked the stall and move towards OZ first but it seems that the UKMO has nailed the U turn back towards the Coral. Some other models and ensembles can't wait for Oma to die

[RODALCO]

Oma means grandmother in Dutch. Interesting name for a cyclone.
Let's hope it is not becoming the gransmother of tropical cyclones.

[Nev]

In te reo Māori, 'Oma' means to move quickly on foot, flee or escape…

[Cyclone Tracy]

As TC Oma is about to lose her status and become a drifting tropical low (for now), its always good to see how the 2 best mean track ensembles faired against each other from 100 hours ago.

The UK has dropped EC's pants in the last 100 hours and IMO is still the undisputed champ in the South Pacific.