The match will still be played at Genoa's Luigi Ferraris stadium but kicks off on Friday at 5.15pm local time (1615 GMT).
"The Italian rugby federation announces that the test match between Italy and Argentina, originally scheduled for Saturday at the Luigi Ferraris stadium, has been brought forward to Friday at 17.15pm," a statement from the Fir said.
Earlier, the Saturday fixture was cancelled over fears that predicted heavy rain in Genoa on Saturday would lead to further chaos.
So far this month, five people have been killed in flood-related incidents. Fir officials said the decision was taken following hours of meetings with officials from the city, including those tasked with guaranteeing public safety.
"The decision was made because of the very strong possibility of heavy rain on Saturday. Security officials felt that holding the match then posed just too much of a risk."
The death toll from the latest wave of storms to batter northern Italy rose to five on Thursday as floods and landslides continued to wreak havoc across the region.
Genoa suffered particularly badly during heavy floods last month when millions of euros' worth of damages were caused and people were forced from their homes.
The floods also badly affected the pitch at the Luigi Ferraris stadium, which is usually shared by Serie A sides Genoa and Sampdoria.
The statement added that the choice of hour for Friday's game was "necessary to safeguard the proper arrival and departure of the public".
"All tickets that have been sold will still be valid for the game."
Italy began their November Test series with a morale-boosting 24-13 win over Samoa in Ascoli last week.
But after moving on to Genoa at the start of the week, the Azzurri were forced to train indoors due to poor conditions outside.
The game against Argentina will be the Italians' second in the three-Test November series, ahead of meeting South Africa in Padua next weekend.