12:00 PM | **Brutally cold air mass likely to invade the central US next week and then spread to the east coast**
All signs point to the invasion of a brutally cold air mass into the central US next week that will make its way to the east coast around mid-week. This upcoming Arctic air outbreak looks quite similar to the air mass that impacted the central and eastern US during January 1985 which followed a major stratospheric warming event - much like what we have just experienced over the past several weeks. This kind of air mass has the potential of becoming quite a news making event for the Upper Midwest/Great Lakes/Northern Plains and could result in actual air temperatures as severe as 25 degrees below zero in Chicago – awfully close to the all-time low of -27°F set in January 1985.
Today’s unseasonably mild weather in the eastern US will be replaced by another cold air mass following a late day passage of a strong cold frontal system. Indeed, the next couple of days will be colder-than-normal in the Mid-Atlantic region despite some sunshine each day and lows tomorrow night are likely to be in the teens in much of the I-95 corridor. An even colder air mass is in the offing for later next week.
By Monday of next week, low pressure will likely be located over the Upper Midwest and it may spread some accumulating snow across the Great Lakes region while at the same time strong high pressure will be diving southward through Canada. By Tuesday, this low pressure system will shift to a position over the eastern Great Lakes and a strong cold front will trail it on its south side through the eastern US. Brutally cold air will push into the Northern Plains by Tuesday and the winds will be quite strong producing dangerously cold wind chill values. The cold front will slide through the eastern states by mid-week and this will open the gates for the Arctic air mass to reach the east coast. Temperatures on Wednesday and Thursday will be quite amazing on a large-scale basis from the Upper Midwest to the east coast. Chicago, for example, could see temperatures drop to 25 degrees below zero which is within shouting distance of its all-time of -27°F set on January 20, 1985. High temperatures in parts of the Mid-Atlantic region could easily hold in the single digits next Thursday and wind chills will be a factor as well.
The 1984/1985 Stratosphere Warming Event
Some stratospheric warming events in recent history have, in fact, been followed by widespread very cold air outbreaks across the central and eastern US - usually some two to three weeks after the initial upper atmosphere warming. For example, a major SSW event began in December 1984 and continued into early January of 1985 and this was followed by a period of extreme cold in the central and eastern US during the latter half of January 1985. In fact, it turned out to be so cold for Ronald Reagan’s second inauguration on January 20th, 1985 that all outdoor activities for that day were moved inside to protect the public. Interestingly, the month of December in 1984 actually was warmer-than-normal in much of the eastern half of the nation. The Arctic air outbreak in late January of 1985 produced the coldest temperature ever recorded in Chicago of -27°F and that may be threatened next week.
The good news is that it almost has to get warmer following this cold air outbreak since this is likely to be the coldest air mass in North America next week - and, yes, spring training is only about 18 days away.
Meteorologist Paul Dorian