Porterfield - managed 20 runs in the gloom.
Just two games saw play as rain wreaked havoc with the day's LV County Championship programme.
Both divisions suffered as five games were abandoned for the day without a ball being bowled.
Just 13 balls were bowled in Kent's match against Surrey with Canterbury yielding 2.1 run-less overs on day two, while play started at 5pm in Middlesex's clash with Gloucestershire at Lord's.
The visiting side took to the crease for 11 overs after Middlesex immediately declared their first innings on 313 for seven in response to Gloucestershire's 218 all out.
William Porterfield made 20 not out in that time, with Kadeer Ali adding the other 10 in a score of 30 for none with a day to play.
Wet conditions on the fourth day ensured draws in the Division Two match between Derbyshire and Glamorgan and Worcestershire's top-of-the-table meeting with Warwickshire at New Road.
Worcestershire match were deducted two points for a slow over-rate - something they had hoped to remedy this morning if play had been possible.
But both sides will nevertheless be confident of winning promotion, with the Pears 16 points ahead of their rivals, 25 short of guaranteeing Division One cricket next season.
The third day of all three remaining top-tier matches - Durham's match against Lancashire, Nottinghamshire versus Somerset and Sussex's clash with Yorkshire at Scarborough - was also washed out without a ball being bowled.
The outcome is particularly frustrating for a Yorkshire side who are running out chances to pull themselves out a relegation battle.
Their chances of a win over Surrey looked promising when they dismissed their opponents for a modest 265 all out, but after slumping to 133 for seven in return they now face the prospect of collecting no batting points in a rain-ruined draw.
With just two matches left, against reigning champions Sussex and title hopefuls Somerset, retiring captain Darren Gough faces a struggle to avoid going out on a whimper.