Observed and forecast tracks: southern hemisphere 2010-11

All tropical cyclones in the southern hemisphere season in 2010-11 are listed below including details of their start and end dates and maximum sustained wind (MSW). Qualitative comments are included on the performance of the Met Office global model in predicting the track of each tropical cyclone.

Click on the name of the tropical cyclone to see a chart of the observed track and forecast tracks from the Met Office global model. Verification statistics on each tropical cyclone are available upon request from tropical_cyclones@metoffice.gov.uk. At the end of the season a verification report on the performance of the Met Office global model will be published.

South-West Indian (west of 90°E)
Name & IDStart & end dates1-/10-minute MSWComments on Met Office global model forecasts
01S25-29 October35/30 knots01S briefly reached tropical storm status according to JTWC, but not according to RSMC La Reunion
Abele (03S) *129 November-04 December75/70 knotsTrack errors were above last season's average due to a slow bias.
Bingiza (13S)10-18 February100/90 knotsApart from a couple of early forecasts that predicted a track east of Madagascar, tracks forecasts were good. Errors were below last season's average and skill scores against CLIPER were high. There was a slight slow bias.
Cherono (18S)17-22 March40/40 knotsTrack forecast errors were below last season's average for this storm. Only forecasts to 36-hours ahead were verified.

*1: Moved into the Australian region

South-West Indian tropical cyclone names

South-West Indian observed tracks in 2010-11

Australian (90-160°E)
Name & IDStart & end dates 1-/10-minute MSWComments on Met Office global model forecasts
Anggrek (02S)30 October-04 November55/50 knotsTrack forecast errors were very low for this storm. The gradual turn towards the right was well predicted.
Tasha (04P)24-25 December35/40 knotsTasha only briefly reached tropical storm status as it made landfall and no forecasts were verified.
Vince (06S)12-16 January40/40 knotsVince was a tropical storm for a couple of days and the track errors were below last season's average. The 180 degree turn of the storm was well predicted.
Zelia (07P) *214-17 January90/85 knotsTrack forecast errors were a little high at short lead times, but low at long lead times. Skill scores against CLIPER were high. The acceleration of the storm towards the south-east was well predicted.
Anthony (09P)23-30 January45/55 knotsTrack forecast errors were high at long lead times, but low at short lead times. Skill scores against CLIPER were very high. The 180 degree turn of the storm was well predicted, but the detail of the track after the turn was less well handled.
Bianca (10S)25-29 January115/90 knotsThe track of Bianca was well predicted with low errors and high skill scores. The turn of the weakening system towards Perth was well predicted.
14S11-12 February35/30 knotsThe 10-minute average winds did not reach tropical storm strength and no forecasts were verified for 14S.
Carlos (15S)15-26 February55/60 knotsTrack forecasts errors were extremely low for this storm and skill scores high. Although there was a slight slow bias, the track along the full length of the north-west facing coast of Australia was well predicted.
Dianne (16S)16-22 February85/70 knotsA few early forecasts incorrectly turned Dianne towards the coast of Western Australia. This resulted in large track forecast errors at long lead times. However, subsequent forecasts were good, which is reflected in very low errors at shorter lead times and high skill scores.
20S02-04 April35/30 knotsThe 10-minute average winds did not reach tropical storm strength and no forecasts were verified for 20S.
Errol (21S)15-18 April55/55 knotsTrack forecast errors were low and skill scores for this storm.

*2: Moved into the Fiji region

Australian tropical cyclone names
Indonesian tropical cyclone names
Papua New Guinea tropical cyclone names

Fiji (east of 160°E)
Name & IDStart & end dates 1-/10-minute MSWComments on Met Office global model forecasts
Vania (05P)11-15 January60/65 knotsTrack errors were below last season's average for this storm and skill scores were high.
Wilma (08P)22-28 January115/100 knotsTrack forecast errors were above last season's average at long and short lead times, but near to average at times in between. Several forecasts failed to predict the speed of turn southwards towards New Zealand, which accounts for some of the large track forecast errors.
Yasi (11P) *330 January-03 February135/115 knotsThe Met Office global model was able to predict the formation of Yasi several days before it occurred. These early forecasts also predicted the track across the Coral Sea to landfall over Queensland with remarkable accuracy. Once Yasi had formed track forecast errors were all below last season's average and skill scores very high. A few forecasts predicted landfall a little too far north, but generally forecasts were excellent.
Zaka (12P)06-07 February45/50 knotsZaka was fairly short lived. Forecasts had a slow bias as the storm accelerated towards the south-west.
Atu (17P)18-24 February115/95 knotsThe model predicted the acceleration of Atu towards higher latitudes well, although was a little slow. However, track forecast errors were below last season's average.
Bune (19P)23-28 March75/70 knotsOnly at 96-hours were track forecast errors significantly above last season's average. Otherwise errors were near to or below this average. There was a slow and right-of-track bias in forecasts.

*3: Moved into the Australian region

Fiji tropical cyclone names

Western Australian observed tracks in 2010-11
Eastern Australian and South Pacific observed tracks in 2010-11

South Atlantic
Name & IDStart & end dates 1-/10-minute MSWComments on Met Office global model forecasts
Arani (90Q)10-16 March45/- knotsArani was a rare South Atlantic storm. It only briefly reached tropical storm strength.

Note on estimated wind speeds

1-minute MSW: Maximum sustained wind (knots) averaged over 1 minute (JTWC Hawaii)
10-minute MSW: Maximum sustained wind (knots) averaged over 10 minutes (Southern Hemisphere RSMCs and TCWCs)

Note: Although 1-minute average winds should be stronger than 10-minute average, this may not be the case here since estimates are obtained from different warning centres.

Last updated: 17 December 2013