A massively large positive 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. anomaly over Greenland (+24 hPahPa A Hectopascal is the SI unit of pressure and identical to the Millibar) in December, combined with lower than average pressure to the west of Corunna in the Atlantic (-10 hPa), produced and odd looking trough of low pressure aligned SW-NENE North East to the west of the UKUK The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland. in the mean pressure chart for the month. It’s one of those months, split into two diametrically opposed weather types NE-CNECNE Cyclonic Northeasterly-CSW-CW, that tend to cancel each out over the month, to produce a rather misleading mean MSLP chart.
