As the dry days have continued through autumn, we have now well and truly passed the mystical 'ANZAC Day break.' But how likely is it that we have ANZAC Day breaks anyway? And in what percentage of years do we get a breaking rain before mid-May?
To answer the latter question, we've used the CliMate app to check the percentage of years we see the breaking rain arrive before May 15. This data is sourced from the Bureau of Meteorology (via the CliMate app) from 1900 onwards.
We've defined a 'breaking rain' as at least 20mm of rain over a three-day period. We'll acknowledge that this isn't perfect—in some scenarios, a break consists of a few small rains over a longer period. There are also soil type differences, with heavier soil types often requiring more than 20mm to really wet up and lighter soils not needing nearly as much. But it still forms a good guide overall.
The table below shows the percentage (%) of years since 1900 in which the break has arrived prior to May 15 for various cropping locations around South Australia, Victoria, and Tasmania.
| Town | Percentage % |
| Crystal Brook | 47% |
| Booleroo Centre | 44% |
| Balaklava | 40% |
| Saddleworth | 50% |
| Maitland | 56% |
| Bute | 45% |
| Minnipa | 26% |
| Cleve | 37% |
| Cummins | 45% |
| Pinnaroo | 32% |
| Loxton | 26% |
| Wolseley | 50% |
| Coomandook | 42% |
| Horsham | 48% |
| Swan Hill | 42% |
| Hamilton | 66% |
| Cressy | 67% |
| Longford | 69% |
| Tunbridge | 53% |
| Deloraine | 86% |
This shows that the 'average' breaking rains occurring on Anzac Day isn't an accurate or realistic guide. For most South Australian locations, we historically don't see a 'proper' break occurring before May 15 in more than half a year.
It is important to remember that the timing of the break is outside of our control. But we do have significant control over our management and preparation for when we are faced with a 'dry start'.