Charts of the Past
BAMOS
Mar 2019
with Blair Trewin
4 January 1979
The opening days of 1979 were marked by a contrast sometimes
seen in an Australian summer, between extreme rains in the
north and extreme heat in the south, with the combination of a
tropical cyclone and a blocking high in the Tasman Sea.
Tropical Cyclone Peter formed in the Gulf of Carpentaria on 30
December, and crossed the west coast of Cape York Peninsula
as a category 2 system the next day. After crossing the Cape, it
reformed in the Coral Sea and remained near the coast in the
vicinity of Cooktown, weakening below cyclone intensity by
the 3rd but remaining in an active monsoon trough before its
eventual dissipation.
Peter’s slow movement contributed to extreme and long-lasting
rainfall in the easterly flow on its southern flank. The heaviest
falls were focused on the Cairns region with especially extreme
totals in mountainous areas. The summit of Bellenden Ker
received multi-day rainfall totals unprecedented in Australian
meteorological history, with a two-day total of 1947 mm on 4–5
January, and a total of 3847 mm over the first eight days of the
month. (The former is more than double the official Australian
daily record; no daily observation was made on 4 January, but
as other sites in the region received substantially more rain on
the 5th than on the 4th, it is likely that the total on the 5th was
well over 1000 mm). A site at the base of Bellenden Ker received
756 mm on the 5th, whilst other extreme totals included 535
mm at Kuranda on the 4th and 485 mm at Mount Sophia on the
5th. Kuranda exceeded 250 mm on each of the five days from
2 to 6 January, with a total for the period of 1949 mm, whilst
Cairns itself topped 100 mm on each day (the only instance of
more than three successive three-figure days) with a record
five-day total of 854 mm. Further rains later in the month led
to Bellenden Ker reaching an Australian record monthly total
of 5370 mm.
There was major flooding in several coastal rivers, especially the
Barron, with the Tully, Murray and Herbert rivers also affected.
Two deaths were attributed to the floods, with widespread rural
flooding and transport disruptions but limited urban impacts.
The effects were largely limited to Cape York Peninsula and the
north tropical coast, with no significant falls from Townsville
southwards or in most inland areas.
Further south, extreme heat affected many parts of southern
Australia. Mundrabilla, on the Nullarbor, reached 49.8 °C on the
3rd, at the time a Western Australian record (equalled at Forrest
ten days later, and subsequently broken in 1998). Ahead of a
trough moving east, very high temperatures also occurred in
South Australia on the 4th, and Victoria and southern New
South Wales on the 5th. Kyancutta reached 47.1 °C on the 4th,
whilst next day several northwest Victorian sites exceeded
45 °C, including 46.8 °C at Mildura, the highest temperature in
Victoria between 1939 and 1990. The coast missed the most
extreme heat, but Adelaide still reached 42.0 °C and Melbourne
38.8 °C. A trough cooled conditions on the coast after the 5th,
but extreme heat continued inland, with Mildura having six
successive days above 40 °C and Canberra seven successive
days above 35 °C. Despite the heat there were no major fires,
with fuels still relatively damp after a generally wet and cool
December. January went on to be the hottest on record at the
time for Victoria and South Australia (and still ranks as fourth-
hottest in both States), and the second-hottest for Australia.
Synoptic chart for 0000 UTC, 4 January 1979
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