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Weather Glossary - J


Jet max

(Speed Max, Jet Streak) A point or area of relative maximum wind speeds within a jetstream.

Jet streak

A local wind speed maximum within a jetstream.


Relatively strong winds concentrated in a narrow stream in the atmosphere, normally referring to horizontal, high-altitude winds. The position and orientation of jetstreams vary from day to day. General weather patterns (hot/cold, wet/dry) are related closely to the position, strength and orientation of the jetstream (or jetstreams). A jetstream at low levels is known as a low level jet.


Joint Typhoon Warning Center. The JTWC issues warnings and forecasts for tropical systems across the Pacific and Indian Oceans.

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Perth blanketed in smoky haze from prescribed burns as alert issued

19:01 EDT

A smoke haze across Perth from prescribed burns has prompted an alert from the Department of Parks and Wildlife.

Myrtleford flood clean-up continues two weeks on

15:50 EDT

It has been more than two weeks since floodwaters inundated parts of Myrtleford in Victoria, but there is still some cleaning up to do.

From wind to rain in the southeast

11:52 EDT

Victoria and Tasmania won't have time to recover from damaging winds this morning, with rain threatening to cause flooding across both states in the next 24 hours.