SPRING will be warm and wet, according to the latest data from the CSIRO and the Bureau of Meteorology.

And a La Nina event is now "more likely than not" to occur this year.

The Bureau's climate prediction services manager Andrew Watkins said if recent trends in the Pacific climate patterns continued, a La Nina would be established before the end of winter.

"Computer model forecasts show a significant likelihood of a La Nina in 2010," Dr Watkins said.

At the Victorian Farmers Federation annual general meeting and conference in Bendigo last week, the Department of Primary Industries' Graeme Anderson spoke about Victoria's weather patterns.

"The trend for warmer temperatures nationally looks set to continue," Mr Anderson said.

"Historically, looking at records from the Bureau from 1900 to 2007, we see the trends for temperature continuing which of course have implications for farmers and particularly in southern Australia.

"If there is a one degree increase in temperature, southern Australia will get drier and northern Australia, in the tropics, will get wetter.

"We are not actually having more variability in our weather, we are however seeing consistently warmer weather with higher pressure systems, stronger storm fronts and the seasons are shifting, and we are strongly influenced by spring rain."

However these weather conditions will be ideal for locust hatchings - something farmers are concerned about.

VFF president Andrew Board said the organisation met with the State Government last week to further discuss the strategy to fight locust hatchings in spring.

"The $43.5 million (on June 11) pledged by the State Government to fight the worst locust plague since 1973 will help to (give farmers) a 100 per cent rebate on chemical to (fight the locusts)," Mr Broad said.

"Our effort in this area alone should justify the value of VFF membership. The reality is that you are subsidising your free-loading neighbour if they are not a member."

He said about $20 million was dedicated to funding chemicals to spray public land.