Added a bit more logic to the Extremes viewer in my Reanalysis MSLPMSLP Mean sea level pressure is the pressure at sea level, or, when measured at a given elevation on land, the station pressure reduced to sea level assuming an isothermal layer at the station temperature. application to distinguish if the centre of the vortices it found, be it high or low, was on the edge of the chart. Here are the results from all Decembers back to 1948.
