Why Weather Forecasting Is Harder in the Southern Hemisphere

The Data Gap

Weather forecasts in the Southern Hemisphere face unique challenges compared to the Northern Hemisphere because the south has much less land mass, fewer people, fewer major cities, and less funding for observations. Atmospheric scientists like Dr Kimberley Reid from the University of Melbourne note that the south lacks enough surface observations and weather balloons. In the 1980s, a three-day forecast was about 90 per cent accurate in the north, but just over 80 per cent in the south. Michael Logan from the Bureau of Meteorology, or BOM, states that the south lagged behind into the 2000s.

Satellites Help

In recent years, the Southern Hemisphere has narrowed this accuracy gap to almost match the north. This improvement comes from international satellites rather than extra local weather stations or balloons. Australia uses data from 40 satellites owned by other countries, including the US and Japan. These international satellites provide more than 90 per cent of the data used for Australian weather forecasts. The BOM receives between 13.5 and 14 million observations daily from these satellites.

Future Worries

Weather is naturally chaotic, meaning tiny variables cause large flow-on effects over a couple of days, and this problem compounds when data collection points are scarce. While satellites provide massive amounts of data, they cannot forecast everything, and scientists warn that many current satellites are nearing the end of their working lives. Dr Martin Jucker from the University of New South Wales points out that some replacement satellites have been cancelled, meaning future replacements will arrive late.

Context

Modern meteorology relies heavily on numerical computing models that ingest millions of global data points every day to simulate atmospheric conditions. Because the Southern Hemisphere is covered largely by oceans where traditional weather stations cannot be placed, global satellite networks remain essential for filling blind spots. As global climate patterns shift and extreme weather becomes more frequent, maintaining continuous satellite coverage is vital for timely public warnings.