MEMPHIS, TN (WMC) - The Vernal Equinox or Spring as most people call it began at 11:15 Tuesday morning and it started on a cloudy, rainy, and very chilly note.
The average high temperature for March 20 is 65 degrees. The high this Tuesday was 56 but that occurred just after midnight and temperature steadily fell into the mid-40s for the rest of the day.
At 3 p.m. Tuesday the temperature was 44 degrees. That's more than 20 degrees below the average high for the date and for the first night of spring there were frost advisories and freeze warnings in place.
If cold weather is not your thing then you may like the news coming from the Climate Prediction Center where above average spring temperatures are being forecasted. Although, the majority of people wait for the Vernal Equinox to signal the start of spring, for meteorologists Spring began March 1 and goes through May 31.
Meteorologists and climatologists break each season down to three month periods. The March, April, and May forecast for a warmer than average spring is based on a couple of key factors.
One factor is based on the weakening of La Nina in the coming weeks. La Nina is the below average cooling of Pacific waters along the equator and we have had just that this past winter.
New sea surface temperature data shows a warming trend taking place reversing La Nina to neutral or average conditions. During this neutral phase, average precipitation and temperatures can be anticipated for the southeastern U.S.
However, during the recent La Nina, a drier than average pattern was in place in the southwest and that drier than average pattern would likely continue in a neutral pattern, which is also the second factor of this equation.
A dry ground warms much faster than a wet ground and with air patterns generally moving west to east that would carry that warmer air being radiated into the atmosphere from the dry surface across the southern tier of the U.S.
Because of the very dry conditions that are in place and likely to persist through spring, this would allow for extreme heat to build in the southwest and be carried east.
So, a weakening La Nina and a developing dry pattern could create a much warmer pattern here in the Mid-South and for much of the nation now through the end of May. We'll be tracking it and keep you posted on what could be a warm spring season.