Recent dry conditions across southeast England, including London, with minimal rainfall recorded through mid-May, have elevated trader focus on the 10–20 mm total precipitation outcomes. Climatological averages for the month hover near 50 mm, but persistent high-pressure patterns and subdued Atlantic moisture transport have suppressed convective activity and frontal systems so far. Extended-range forecasts from the Met Office and ECMWF indicate below-normal rainfall probabilities for the remaining fortnight, though model spread introduces uncertainty around potential late-month showers. These factors align with the closely matched leading probabilities near 41–42 %, reflecting trader assessment of ongoing subsidence and limited orographic enhancement over the region.