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It has been long said that, "April showers bring May flowers."  However, for the south and mid-south regions of the Continental United States, things occur a bit earlier these days...  climatologically that is.

As the transition from winter to spring occurs in the Northern Hemisphere, the days grow longer, due to the 23 1/2 degree tilt of our planet's axis.  By the point of the Vernal Equinox, which marks the start of the spring season in the Northern Hemisphere, the polar jet stream has retreated enough northward, where the southeastern quadrant of the United States begins to feel the effects of the sub-tropical jet.  Those particularly affected during this time of year include Southern Kentucky and extreme Northern Tennessee, due to their mid-level latitudes.

As the polar jet retreats northward, a ridge of High Pressure normally builds on the trailing edge of which.  This tends to mark the entrance sector and the leading edge of sub-tropical air, where temperatures in the upper-60s/ lower-70s mainly occur.  Hence, this is why we here in South Central Kentucky tend to have 3-5 days of "fair" weather, before seeing consecutive days of rain.  Temperatures following the precipitation normally remain at or slightly above average during this period as well, again because the core of the colder air remains confined to portions of the Ohio Valley and Great Lakes Region.

This also marks the time of year when the weather can be at its worst.  As many are aware, March marks the start of Severe Weather Awareness Month, because it proceeds the spring season.  Severe weather can occur with little or no advance warning during this time, because of the temperature gradient.

In other words, think of a staircase.  Temperatures at the bottom of the stairs are in the lower-70s.  However, just a few steps up, they fall 40-degrees or so, with readings in the 30s.  Its where this warm, moist airmass does battle with cold, dry air that severe weather occurs.

However, as March 12 shows us, winter does not necessarily give-up without a fight, as 3-inches of snow was recorded in the City of Bowling Green, following a temperature of 80-degrees.

Bottom-line...  if you do not like the weather in South Central Kentucky...  wait a day or two.

JB