Milking the Weather - March 2011 Edition
Seasonal update and outlook
Summary as of 2nd March, 2011
La Niña weakens in the Pacific
- The La Niña event reached peak intensity in early January and is now weakening.
- We are following a typical Australian La Niña pattern, with a stronger influence on rainfall and temperature during winter to mid-summer, and then weakening during the following autumn (where we are heading to now). The relative warming of the ocean temperatures in the Pacific Ocean are consistent with the breakdown phase of La Niña events.
- However, the atmospheric indicators of the La Niña, such as cloudiness, SOI and trade winds, have remained strong. The February SOI was the highest on record. As the ocean’s surface warms these atmospheric indicators are expected to weaken over the coming month.
- The Indian Ocean Dipole (IOD) has limited influence on rainfall during the months from December through to April. It is currently in neutral territory which is typical for this time of year and it is predicted to remain here until spring.
Figure 1: The Southern Oscillation Index (SOI) remains strongly positive indicating that the pressure at Darwin is lower than at Tahiti (an indicator of prevailing La Niña conditions).
Seasonal model forecasts for Victoria (from The Fast Break February 2011)
| Current outlook for Autumn (MAM) | |
|---|---|
| Pacific Ocean: | Cool (weak La Niña) |
| Indian Ocean: | Slightly cool |
| Rainfall: | Average / Slightly Wetter |
| Temperature: | No clear signal |
| Current outlook for Winter (JJA) | |
|---|---|
| Pacific Ocean: | Slightly cool /Cool (weak La Niña) |
| Indian Ocean: | Neutral |
| Rainfall: | Average / Slightly Wetter |
| Temperature: | Average |
This forecast is a summary of a number of global climate models surveyed by the Fast Break.
Why is this outlook different to the three month outlook on the BOM website?
Refer back to the September 2010 to find out why.
To subscribe to the Fast Break newsletter email the.break@dpi.vic.gov.au
Victorian cropping state roundup
The harvest was certainly one to remember, not necessarily for all the right reasons. A wet spring and early summer saw many croppers unable to harvest last seasons bumper crops, but sit back and watch them pass their prime. Most farmers eventually got their crops off, but the majority of this years harvest was down graded to feed quality. While plenty of feed grain is available on the market, there is also large quantities stored on farm. This storage is likely to be trickled out on the market to aid croppers cash flow. The rainfall and wet conditions on the ground also affected the seed harvest. Many are concerned with the viability of the seed, as the later it was harvested the more suspect it will be. Farmers are currently assessing seed supply for quality to ensure that it’s good enough to sow.
Summer rainfall was the highest on record in most grain growing regions. Resulting in more than adequate soil moisture throughout the soil profile in all major cropping districts. The main concern is whether it is still too wet to start planting, with most districts wanting to have seed in the ground by April. Traffic issues have led to increased weed populations and control is now a high priority. Croppers are optimistic that if the seed is viable they should get a good strike and start to the season.
