We can thank ex-tropical cyclone Esther for last week's heavy rainfall. After looping around
northwest WA at the end of February, the system brought extra moisture to southeast Australia.
Parts of central and northern Victoria recorded more than their typical March totals in the first week
of the month. Parts of the northwest have received more than 25 mm, more than 50 mm over parts
of central Victoria, and more than 100 mm in parts of the northeast. The highest totals were at
elevated sites; Mt Buffalo recorded 170 mm in 24 hours.
What does this mean for the autumn break? The autumn break is the first good rainfall after
summer at the beginning of the southern growing season. There are different criteria for the
amounts and timing of the rain you need for an autumn break in different regions of southern
Australia. For parts of Victoria, 25 mm or 30 mm (close to an inch) in the space of a few days to a
week, after 1 March would typically qualify as an autumn break. The autumn break usually arrives
over eastern and southern Victoria during March and April, and the northwest during May.
Using the 25 mm criteria, most of central, all of northeast, and parts of northwest and southeast
Victoria had their 2020 autumn break last week.
Root zone soil moisture is above average across most of the state. Large parts of central, eastern
northern and north-western Victoria have very much above average root zone soil moisture (in the
top 10% of records).
The rainfall outlook for the rest of March shows that parts of northern and eastern Victoria are likely
to be drier than average. There are roughly equal chances for a wetter or drier than average April.
May and June are likely to be wetter than average in the west. Overall, the three-month outlook
from April to June shows increased chances of above average rainfall for parts of the west.
There are roughly equal chances of Maximum temperatures being warmer cooler than average for
most of the State for the second half of March, and April and May.
Minimum temperatures are slightly more likely to be warmer than average in parts of the north and
west for the second half of March, and across most of the State during April and May.