Attachment 3: Summary of Weather Forecast Model Output Operationally Available in the Lead-up to the Race

ATTACHMENT 3
Summary of Weather Forecast Model Output Operationally Available in the Lead-up to the Race

Winds noted in each panel are the strongest mean winds which could reasonably have been forecast from the printed model output, for the area just offshore from Gabo Island at the times the model runs were valid (between 4am and 11pm, local time, on Sunday the 27^th December 1998).

Winds measured in knots (kn). Models are marked "Not available" if the model was not produced or was not received in the forecasting centres.

Run

ECMWF

JMA

GASP

UKMO

US (aviation)

LAPS

MesoLAPS

U/NSW

+120

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

avail Wed at noon

High pressure ridge >

NE’ly20kn

Low(1000) 400km E of Gabo

> SSW’ly 40kn

avail Wed at 6am

High pressure ridge over Bight, Low(995) over S’rn Tasman Sea > SW’ly 20kn

avail Wed morn

Low(1001) over Gabo >

Var winds, SSE’ly developing 25kn

Not Available

Not Available

Not Available

Not Available

+96

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

avail Thur at noon

Low(992) 600km E of Tas >

SW’ly 30kn

High over the Vic highlands >

light/ variable

avail Thur at 6am

High over Gabo >

light/ variable

avail Thur morn

Complex trough over the Tasman sea > SE’ly 25kn

Not Available

Not Available

Not Available

Not Available

+72

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

avail Fri at noon

Low (988) in the S’rn Tasman >

WSW 30kn

Low(998) 400km ESE of Hobart >

SW’ly 35kn

avail Fri at 6am

High west of Bass Strait >

SSW’ly 15kn

avail Fri morn

High near Mt Gambier, Low(1006) 200km E of Sydney > SE’ly 30kn

High over Gabo >

light/variable

Not Available

Not Available

Not Available

+60

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

Not Available

Not Available

avail Fri at 6pm

Low(999) 500km E of Hobart >

SSW 35kn

avail Fri evening

Low(1001) 400km E of Gabo >

S’ly 40kns

Not Available

Not Available

Not Available

Not Available

+48

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

avail Sat at noon

Low(993) 400 km SE of Gabo > SW’ly 45kn

Low(995) 400km E of Hobart >

SW’ly 45kns

avail Sat at 6am

Low(993) 400km E of Flinders >

SW’ly 45kns

avail Sat morn

Complex low(994) E of Tasmania >

SW’ly 40kns

Low(995) 250km E of Hobart >

WSW’ly 45kn

avail Sat 12am

Low(998) over the S’rn Tasman >

SW’ly 25kn

Not Available

Not Available

+ 46

valid Sunday,

27^th at 10UTC

(9pm Sun EDST)

Not Available

Not Available

Not Available

Not Available

Not Available

Not Available

Not Available

avail 8am Sat

spot winds

Bateman’s Bay SSW 28kn

Eden SW 35kn

Run

ECMWF

JMA

GASP

UKMO

US (aviation)

LAPS

MesoLAPS

U/NSW

+36

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

Not Available

Not Available

avail Sat at 6pm

Low(991) 100km E of Flinders > WSW’ly 50kn

avail Sat evening

Low(989) 150km E of Hobart >

WSW’ly 50kn

Low(993) 100km E of Hobart >

WSW’ly 50kn

avail Sat 12pm

Low(989) 150km SE of Gabo >

WSW’ly 50kn

avail Sat 1pm

Low(985) 150km SE of Gabo >

WSW’ly 55kn

Not Available

+ 30

valid Saturday,

26^th at 21UTC

(5am Sunday EDST)

Not Available

Not Available

Not Available

Not Available

Not Available

Not Available

Not Available

avail 8am Sat

spot winds

Bateman’s Bay S 33kn

Eden SW 43kn

+24

valid Sunday, 27^th at 00UTC

(11am Sun EDST)

Not Available

Not Available

avail Sat at 6pm

Low (993)

120 km E of Flinders Is >

WSW’ly 35kn

Not Available

Not Available

avail Sat 12pm Low(993) 300km SE of Gabo > WSW’ly 30kn

avail Sat 1pm

Low(991) 100km E of StHelens >

W’ly 40kn

Not Available

+24

valid Sunday, 27^th at 12UTC

(11pm Sun EDST)

avail Sun noon

Low(989) 500 km E of Hobart >

WSW’ly 45kn.

Low(989) 500km E of Hobart >

SW’ly 45kn

avail Sun at 6am

Low(991) 600 km E of Hobart >

S’ly 45kn

avail Sun morn

Low(987) 600km SE of Gabo >

SW’ly 50kn

Complex Low(992) E of Tasmania >

SW’ly 45kn

avail Sun 12am

Low(992) 400km SE of Gabo >

SW’ly 45kn

avail Sun 1am

Low(990) 400km E of StHelens >

W’ly 45kn

Not Available

Notes :

ECMWF - this is a ‘global’ model created by the European Centre for Medium Range Weather Forecasts.

GASP - Global Assimilation and Spectral Prognosis. This is an Australian produced ‘global’ model.

JMA - ‘global’ model produced by the Japan Meteorological Agency.

LAPS - Local Area Prediction System. This is an Australian produced ‘regional’ (local) area model.

MesoLAPS - as the name suggests, this is a ‘mesoscale’ model and is produced in Australia.

U/NSW - this model is produced by Professor Lance Leslie of the University of New South Wales and can be ‘run’ using initialising data from larger scale ‘global’, ‘regional’ or ‘local’ models which cover the domain of the model. On this particular occasion, this model was ‘run’ in regional mode.

UKMO - this is a ‘global’ model produced by the "Met Office" in the United Kingdom.

US - this is a ‘global’ model produced by the National Centers for Environmental Prediction of the United States National Weather Service.

Model validity times are in UTC. 12 UTC is 11pm Eastern Summer time. 00UTC is 11am Eastern Summer Time.

Availability times vary from office to office and a affected by network traffic and other delays. The times quoted are approximate only.

Positions of systems are stated for descriptive purposes only. They have been estimated off small scale printed charts and are accurate to about 25% of quoted distance.

Central pressure of systems is in hectoPascals to the nearest unit, taken from printed charts as operationally available.

Implied wind speed is estimated off small scale printed charts using a geostrophic wind scale and corrected by up to 30% for isobar curvature and reduced by 10% for surface friction. These values can be expected to be within about 20% of the actual modelled near surface winds. The exceptions to this procedure are the winds taken from LAPS and Mesolaps which were actual modelled winds read off printed wind vector charts.

The term ‘run’ refers to when the model calculations were begun. ie to ‘run’ a computer program.

Run	ECMWF	JMA	GASP	UKMO	US (aviation)	LAPS	MesoLAPS	U/NSW
+120 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	avail Wed at noon High pressure ridge > NE’ly20kn	Low(1000) 400km E of Gabo > SSW’ly 40kn	avail Wed at 6am High pressure ridge over Bight, Low(995) over S’rn Tasman Sea > SW’ly 20kn	avail Wed morn Low(1001) over Gabo > Var winds, SSE’ly developing 25kn	Not Available	Not Available	Not Available	Not Available
+96 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	avail Thur at noon Low(992) 600km E of Tas > SW’ly 30kn	High over the Vic highlands > light/ variable	avail Thur at 6am High over Gabo > light/ variable	avail Thur morn Complex trough over the Tasman sea > SE’ly 25kn	Not Available	Not Available	Not Available	Not Available
+72 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	avail Fri at noon Low (988) in the S’rn Tasman > WSW 30kn	Low(998) 400km ESE of Hobart > SW’ly 35kn	avail Fri at 6am High west of Bass Strait > SSW’ly 15kn	avail Fri morn High near Mt Gambier, Low(1006) 200km E of Sydney > SE’ly 30kn	High over Gabo > light/variable	Not Available	Not Available	Not Available
+60 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	Not Available	Not Available	avail Fri at 6pm Low(999) 500km E of Hobart > SSW 35kn	avail Fri evening Low(1001) 400km E of Gabo > S’ly 40kns	Not Available	Not Available	Not Available	Not Available
+48 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	avail Sat at noon Low(993) 400 km SE of Gabo > SW’ly 45kn	Low(995) 400km E of Hobart > SW’ly 45kns	avail Sat at 6am Low(993) 400km E of Flinders > SW’ly 45kns	avail Sat morn Complex low(994) E of Tasmania > SW’ly 40kns	Low(995) 250km E of Hobart > WSW’ly 45kn	avail Sat 12am Low(998) over the S’rn Tasman > SW’ly 25kn	Not Available	Not Available
+ 46 valid Sunday, 27^th at 10UTC (9pm Sun EDST)	Not Available	Not Available	Not Available	Not Available	Not Available	Not Available	Not Available	avail 8am Sat spot winds Bateman’s Bay SSW 28kn Eden SW 35kn
Run	ECMWF	JMA	GASP	UKMO	US (aviation)	LAPS	MesoLAPS	U/NSW
+36 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	Not Available	Not Available	avail Sat at 6pm Low(991) 100km E of Flinders > WSW’ly 50kn	avail Sat evening Low(989) 150km E of Hobart > WSW’ly 50kn	Low(993) 100km E of Hobart > WSW’ly 50kn	avail Sat 12pm Low(989) 150km SE of Gabo > WSW’ly 50kn	avail Sat 1pm Low(985) 150km SE of Gabo > WSW’ly 55kn	Not Available
+ 30 valid Saturday, 26^th at 21UTC (5am Sunday EDST)	Not Available	Not Available	Not Available	Not Available	Not Available	Not Available	Not Available	avail 8am Sat spot winds Bateman’s Bay S 33kn Eden SW 43kn
+24 valid Sunday, 27^th at 00UTC (11am Sun EDST)	Not Available	Not Available	avail Sat at 6pm Low (993) 120 km E of Flinders Is > WSW’ly 35kn	Not Available	Not Available	avail Sat 12pm Low(993) 300km SE of Gabo > WSW’ly 30kn	avail Sat 1pm Low(991) 100km E of StHelens > W’ly 40kn	Not Available
+24 valid Sunday, 27^th at 12UTC (11pm Sun EDST)	avail Sun noon Low(989) 500 km E of Hobart > WSW’ly 45kn.	Low(989) 500km E of Hobart > SW’ly 45kn	avail Sun at 6am Low(991) 600 km E of Hobart > S’ly 45kn	avail Sun morn Low(987) 600km SE of Gabo > SW’ly 50kn	Complex Low(992) E of Tasmania > SW’ly 45kn	avail Sun 12am Low(992) 400km SE of Gabo > SW’ly 45kn	avail Sun 1am Low(990) 400km E of StHelens > W’ly 45kn	Not Available