Trader consensus on Polymarket heavily favors under 20mm total April precipitation in London at 67.3% implied probability, driven by exceptionally dry conditions through mid-month, with official Met Office data from Heathrow recording less than 5mm accumulated by April 16—far below the 42mm climatological average for the month. High-pressure systems dominating southeast England have suppressed Atlantic moisture inflow, yielding mostly sunny spells and minimal showers following a sodden winter. Recent forecast model ensembles from the Met Office indicate continued settled weather with low precipitation risk through month-end, though inherent forecast uncertainty persists as steering patterns could shift. Key resolution hinges on final tallies from verified gauges like Heathrow, with traders pricing in slim odds for wetter bins amid this prolonged dry spell.