Melbourne's final spring heat record as flooding rain looms
Melbourne has just added another impressive feat to its growing list of spring heat records that have been broken this season.
Wednesday's maximum temperature of 35.5 degrees was impressive on its own, considering it's a whopping 13.5 degrees above average for this time of year and the city's hottest spring day in five years.
Yesterday's scorcher was also Melbourne's 13th day over 30 degrees so far this season, beating the previous spring record of 12 days from 2009. This season's tally of days over 30 is expected to increase to 14 days today, extending the new record and more than tripling the season's long-term average of four days above this mark.
If Melbourne reaches its forecast top of 35 degrees today it will also be the city's first back-to-back 35 degree days during spring for eight years.
The latest record comes less than a week after Melbourne registered nine consecutive days over 28 degrees earlier this month, between Saturday 18th and Sunday 26th. This was also a new spring record for the city, beating the previous record of six days from 2009, 1914 and 1896.
This extended spell of heat also contained six consecutive days above 30 degrees between Monday 20th and Saturday 25th, matching the city's existing spring record from 1896.
After a notably hot end to spring in Melbourne, maximum temperature will be significantly lower during the opening days of summer as heavy rain and thunderstorms inundate the city between Friday and Sunday.
The warm and humid northerly winds that have been devouring spring heat records in Melbourne during recent weeks have primed the atmosphere for a big rain event. A slow-moving low pressure system and associated trough will interact with this abundant atmospheric moisture to produce a prolonged spell of heavy rain and storms during the next three days.
Computer models indicate that 50-150mm of rain could fall in Melbourne between Friday and Sunday, with heavier totals in other parts of the state. If Melbourne receives more than 57mm, this will be the city's wettest three days in four years. Melbourne's monthly average during December is 59mm.
For some areas around Melbourne, this system could produce the heaviest rain in six years. Coldstream could see close to 70mm by the end of Sunday, which would be its wettest three day spell since early 2011.
The impending rainfall will be fuelled by tropical moisture and is likely to produce flash and riverine flooding around Melbourne and in other parts of Victoria. Be sure to keep up to date with the latest warnings during this event, which you can find here: http://www.weatherzone.com.au/warnings.jsp
© Weatherzone 2017