The science behind winter warm-up spells
Every winter sees ups and downs in temperatures swings across the state of Missouri. Some periods of time will see exceptionally cold weather for weeks on end, but other stretches of time can see highs nearly 20 degrees above average.
The last several days in Mid-Missouri has been exceptionally warmer with highs reaching into the upper 60s Monday and upper-40s Tuesday. Typically, the average high for Mid-January in Missouri reaches into the upper 30s.
One significant factor in seeing these warm-ups is the amount of cloud cover. The past two days across Mid-Missouri has seen mostly sunny sky conditions. This means plenty of sunshine has reached the earth's surface allowing for temperatures to warm during the afternoon hours.
The main factor in determining a warming trend across a region is the wind direction in the lower levels. By looking at the direction of winds in the Lower Jet-Stream, the air mass can be tracked. The current system Mid-Missouri is experiencing begins over the Gulf of Mexico and flows through Texas and Oklahoma before arrival. Temperatures in these regions range from the 80s to the 70s along this route during the afternoon hours.
Winds follow pressure trends in the atmosphere. High pressure flows towards lower pressure at all times in the atmosphere in an attempt to create an equilibrium. Winds will follow a similar order to this. Winds are observed to flow counter-clockwise around low pressure systems and clock-wise around high pressure systems. Currently, winds over Mid-Missouri are flowing towards an approaching low-pressure off to the west.
