Current ECMWF and GFS operational runs lock into a robust H5 trough axis over the Midwest by May 5, driving persistent northerly 850mb flow. Forecasted 850mb temps of -4C to -2C, coupled with significant cloud deck persistence, will cap surface warming. This 44-45°F band perfectly aligns with model ensemble means, indicating strong conviction in a sustained CAA pattern. Expect minimal diurnal warming potential. 95% YES — invalid if the H5 trough axis shifts east by 200km.
Current ECMWF and GFS operational runs lock into a robust H5 trough axis over the Midwest by May 5, driving persistent northerly 850mb flow. Forecasted 850mb temps of -4C to -2C, coupled with significant cloud deck persistence, will cap surface warming. This 44-45°F band perfectly aligns with model ensemble means, indicating strong conviction in a sustained CAA pattern. Expect minimal diurnal warming potential. 95% YES — invalid if the H5 trough axis shifts east by 200km.
