Bureau introduces northern rainfall onset outlook

25/06/2015

The Bureau of Meteorology has today enhanced its Climate Outlooks service to include the probability of the northern rainfall onset occurring earlier than normal.

Mr Joel Lisonbee, Senior Climate Liaison Officer, said the Bureau’s northern rainfall onset outlook information will be issued monthly in late June, July and August each year.

The northern rainfall onset occurs when enough rain has fallen to stimulate plant growth after the dry season. This is defined as the date after 1 September when a location has received a total rainfall accumulation of at least 50mm.

“The northern rainfall onset outlook will provide an important and useful service for many industries across northern Australia that need to look ahead for their planning, particularly the agricultural sector,” said Mr Lisonbee.

“Generally, coastal Queensland and the western Top End regions receive the first useful rainfall from the northern rainfall onset in October, and this spreads further south and inland over coming weeks.

“The southern inland regions of the Northern Territory and northwestern parts of Western Australia usually have the latest rainfall onset, around mid-January.”

Mr Lisonbee said the northern rainfall onset refers to the first useful rains for agriculture, and is quite different from the date of the monsoon onset. The monsoon onset occurs when significant, widespread rainfall and changes in the mean wind direction are observed.

“The northern rainfall onset outlook complements the Bureau’s broader Climate Outlooks service, which indicate likely temperature and rainfall variations over the next three months, driven by large-scale shifts in the climate such as El Niño or La Niña events.

“The introduction of the northern rainfall onset outlook is part of the Bureau’s ongoing commitment to the continual improvement of its Climate Outlooks service to meet the needs of a range of stakeholders.”

The northern rainfall onset outlook was developed with support from Managing Climate Variability (MCV), a consortium of primary industry research and development corporations.

To view the outlook visit: www.bom.gov.au/climate/rainfall-onset/

The Bureau is now using Twitter to distribute information for the community. For more on the northern rainfall onset outlook, follow:

• @BOM_NT
• @BOM_WA
• @BOM_Qld