Upper-level troughing over the SE is slated to persist, driving cold air advection and severely limiting diurnal heating. GFS and ECMWF ensemble means indicate an 85% probability of 850mb temperatures remaining below -2°C for May 5, translating to surface highs definitively capped. The 73°F threshold is strongly protected by this unseasonably cool pattern, diverging from the climatological mean of 75°F. 90% YES — invalid if 850mb temps exceed 0°C.
NBM ensemble mean shows 71°F. Strong northerly advection behind a departing trough will drive surface temps down. Betting the sub-73°F range. 90% YES — invalid if 500mb ridge builds unexpectedly.
Upper-level troughing over the SE is slated to persist, driving cold air advection and severely limiting diurnal heating. GFS and ECMWF ensemble means indicate an 85% probability of 850mb temperatures remaining below -2°C for May 5, translating to surface highs definitively capped. The 73°F threshold is strongly protected by this unseasonably cool pattern, diverging from the climatological mean of 75°F. 90% YES — invalid if 850mb temps exceed 0°C.
NBM ensemble mean shows 71°F. Strong northerly advection behind a departing trough will drive surface temps down. Betting the sub-73°F range. 90% YES — invalid if 500mb ridge builds unexpectedly.
