Weather has already washed out three games at the Melbourne stadium during this tournament and the decider could become the fourth.
Up to 20mm of rain and a possible storm is expected for Melbourne on Sunday, with the Bureau of Meteorology forecasting a 100 per cent chance of showers.
A rematch of the famous 1992 ODI World Cup decider at the same venue, Pakistan and England are trying to put the dire weather predictions to one side.
England's only loss of the World Cup so far came in a rain-shortened contest against underdogs Ireland at the MCG on October 26.
"The Ireland match was a big disappointment for us as a team but it certainly feels a long time ago now," England captain Jos Buttler told reporters at the MCG on Saturday.
"Being able to sit in this position on the eve of the World Cup final, we have learnt quite a few lessons throughout that game.
"The weather around Melbourne was dominating the whole tournament at that stage and was definitely a distraction at times.
"We've seen a reaction to that game in the rest of the cricket we've played."
To constitute a match, a minimum of 10 overs is required per team in the final, unlike the group stage when only five overs per-side was needed to complete a game.
If the final is washed out, governing body the International Cricket Council has left Monday as a reserve day with play beginning at 3pm.
But Melbourne's weather is looking just as ominous then, with a 95 per cent chance of showers and up to 10mm of rain forecast for Monday.
If play starts on Sunday and is stopped the game will resume on Monday.
In the event rain washes out any prospect of play the competing teams will share the trophy.
England are attempting to add a T20 World Cup to the 50-over trophy they claimed at home in dramatic circumstances in 2019.
Their only victory in a 20-over World Cup final came in 2010 when they defeated Australia by seven wickets in the West Indies.
After their shock loss to Ireland, England have found form and are coming off a blistering 10-wicket thumping of India in the semi-finals.
"I've certainly had a few dreams about that and it really links back to what you were like as a kid, in the garden with your brother and sister, pretending to lift a trophy," Buttler said.
"To be able to have the opportunity ... to live that kind of thing out is incredibly special."
Fast bowler Mark Wood and batter Dawid Malan missed the resounding triumph over India in Adelaide on Thursday and remain in significant doubt to return for the final.
Pakistan will likely take an unchanged team into the decider after overcoming New Zealand by seven wickets in their semi-final.
Babar Azam's side has hit form at the right end of the tournament, becoming the first team in T20 World Cup history to qualify for the final despite losing their opening two games.
"The way our team (has) come back ... they perform very well," Azam said on Saturday.
"We are playing good cricket in the last four matches so will try to continue that momentum."
TWENTY20 WORLD CUP FINALS
2007: India defeated Pakistan by five runs
2009: Pakistan defeated Sri Lanka by eight wickets
2010: England defeated Australia by seven wickets
2012: West Indies defeated Sri Lanka by 36 runs
2014: Sri Lanka defeated India by six wickets
2016: West Indies defeated England by four wickets
2021: Australia defeated New Zealand by eight wickets.
