ECMWF ensemble means for April 27 indicate a 65% probability of achieving 18°C or higher, driven by warm air advection from continental Europe under a developing ridge. Boundary layer mixing is projected to be robust, pushing observed maxima. Current GFS deterministic runs corroborate this trend, showing peak daytime temperatures hitting 19°C. The synoptic pattern strongly supports a continental airmass overcoming any transient maritime influence. 70% YES — invalid if a sustained low-level stratus deck persists into the afternoon.
ECMWF ensemble means for April 27 indicate a 65% probability of achieving 18°C or higher, driven by warm air advection from continental Europe under a developing ridge. Boundary layer mixing is projected to be robust, pushing observed maxima. Current GFS deterministic runs corroborate this trend, showing peak daytime temperatures hitting 19°C. The synoptic pattern strongly supports a continental airmass overcoming any transient maritime influence. 70% YES — invalid if a sustained low-level stratus deck persists into the afternoon.
