The storm across the midwest that’s in the process of developing is going to become a real monster. The 12z GFS deepens this storm to an incredible 958mb over northern Minnesota by tomorrow afternoon! To put this in perspective during the Hurricane of 1938 the pressure in Hartford dropped to 949mb and a normal pressure is about 1013mb!
The current low pressure record for the state of Minnesota is 962mb set in Albert Lea on November 10, 1998. There are only a handful of non-tropical storms to produce some 960mb pressures in the lower 48.
The Cleveland Superbomb in January, 1978 produced a pressure of 958mb in Cleveland. A vicious nor’easter in March 1914 produced a pressure of 961mb in New York City with lower pressures recorded over Long Island (probably in the 950s).
It’s exceptionally rare to see pressure readings drop to this level across the continental United States from a non-tropical storm. Sub 960mb lows occur once every other decade probably. The last time we had one come close was the November, 1998 bomb in Minnesota. The following winter was exceptionally warm across virtually the entire country. We’ll see if this winter follows suit.