A new prime minister. A snap general election. A further referendum on EU withdrawal. Any one of these events is possible during the coming months. It is even conceivable that all three happen and we have a triple whammy of political drama.

You will note my use of the slippery qualifiers “possible” and “conceivable”. Only charlatans and fools will claim to be absolutely confident that they know how the febrile plot of Brexit is going to develop. So we are best off assigning probabilities to potential events.

Theresa May has survived thus far because many of her colleagues are frightened by the thought of a chaotic and vicious Tory leadership contest. And while many lust after her job, few really want it now. These will remain shielding factors, but the fragility of her position and the intensification of Tory infighting will heighten her vulnerability this autumn. The more so if her party conference in October is as calamitous as last year’s coughing-fit, set-collapsing debacle. I put the chances of Mrs May being ejected at 40%.

Labour’s leadership would like an autumn election, but can’t get one simply by wishing for it. The terms of the Fixed-term Parliaments Act mean that an early election can be triggered only if at least some Conservative MPs are willing to vote for one. That seems highly improbable, but the passions aroused by Brexit make it wise to never say never. So it is a 15% chance that there will be an election this autumn.

The likeliest route to another referendum is MPs refusing to approve the Brexit deal that the government comes back with (if it manages to do a deal, a big if). Handing the problem back to the people might be the only way to resolve parliamentary stalemate. The chances of another referendum are edging up and I now put them at 30%.

Finally, we ought to assess the probability that a good Brexit deal that keeps nearly everyone content has been agreed by Christmas. That’s easy. The answer is 0%.