Alonso is currently in his fourth season back at McLaren but has had to put up with a severe lack of performance, even since the team ditched Honda engines for Renault power at the end of last season.
The two-time world champion has still not picked up a podium finish since early 2014 and is currently considering his options; his contract with McLaren expires at the end of 2018 but there is an option to extend.
The Spaniard looks set to give fans an update on his future, having written “14-08” alongside a countdown gif on his Twitter profile last week, suggesting today would be the day.
He also said last month that F1’s summer break would be the right time for a decision.
“Probably in August [I’ll decide], when I’m at the beach tanning, it will be time to think a little bit more,” Alonso said.
“I didn’t have time to think in June or July to be honest. I had quite an intense month.”
Alonso has been linked with a switch to a full-time drive in the IndyCar series and they wrote in reply to the F1 driver “we still on for lunch tomorrow?” with a link to a story full of fans excited about his potential move to the US.
The 37-year-old gave up on catching Michael Schumacher’s F1 record of seven world titles some years ago and has instead focused on motor sport’s “Triple Crown”.
He has already won the Monaco Grand Prix (2006) and last year made his Indy 500 debut, although yet another Honda engine let him down on that occasion.
Alonso has also driven every race in the World Endurance Championship (WEC) this year, winning the 24 Hours of Le Mans race to leave him one feat short of the Triple Crown.
He has previously hinted that driving IndyCar full-time would improve his chances at Indy 500 and with Daniel Ricciardo filling the vacancy at Renault, who are understood to have made enquiries about Alonso’s availability, a move away from F1 looks increasingly likely.
As recently as last week, McLaren boss Zak Brown fanned the flames of a potential move to the US.
“He’s very interested [in IndyCar],” Brown said.
“He likes the series but hasn’t decided yet what he wants to do as it relates to Formula One.
“He thinks [IndyCar] is great racing. He loves the Indy 500. So I think he very much enjoyed that experience. He’s a racer. He likes to race.
“I think winning not only the Triple Crown but all three series [Formula One, IndyCar, WEC], he probably finds intriguing.
“And he likes the racing in IndyCar. It’s extremely competitive. And he likes America, so I know it’s something he would consider.”
Were Alonso to stay in F1, his talent would earn him at the very least an interview with any of the top teams.
But Mercedes have already re-signed both drivers while Sebastian Vettel has taken one Ferrari seat and is unlikely to want to deal with the problems the McLaren driver could bring with him.
And while Ricciardo’s move to Renault appears to have opened up a seat at Red Bull, team boss Christian Horner has already ruled that out.
“I’ve got huge respect for Fernando, he’s a great, fantastic driver, but it would be very difficult to see,” Horner said.
“He’s tended to cause a bit of chaos wherever he’s gone. I’m not sure it would be the healthiest thing for the team for Fernando to join.
“Our preference would be to continue to invest in youth than take a driver who is obviously close to the end of his career.”