Day 8: Central Florida Snow?

Posted by pmarsh on 8 Jan 2010 | Comments Off

Continuing along with the cold air theme of the past few days, tonight we focus on the Tampa, FL area.  The cold front highlighted in last night’s post has moved through most of the Florida peninsula and the cold air is continuing to filter into the state.  At the same time, a mid-level low has organized in the Gulf of Mexico and is beginning to move across Florida.  This mid-level storm is resulting in modest lift atop the cold air at the surface, and this is lift is just enough to produce light showers in the Tampa area (as is indicated by the brighter colors on the radar image below).

Also on the image are current (05 UTC or midnight) temperatures for the Florida peninsula taken from a computer analysis of site-specific data.  The red line farthest north is the 40F line, indicating that any place north of this line is in the 30s.  The temperature contours (isotherms) are done every 4F, with the farthest south line being 52F.  An interesting observation when looking at the temperature contours is the V shape that the contours have.  This V shape is a result of the fact that the temperatures at a given latitude are cooler over the land than over the Gulf of Mexico.  The reason for this is that water heats and cools slower than the land.  At night, the water tends to be warmer than the land and during the day, the water tends to be cooler than the land.  (This temperature contrast is what leads to sea-breezes during the day [cooler air from over the water rushing inland] and land-breezes at night [ coolder air from over the land rushing out to sea].)  Because the water is warmer than land, areas near the coast will stay warmer than those farther inland.  So, all things being equal, the farther inland you go, the greater the likelihood you will be colder than areas closer to the water.

So why is all of this important?  The last time snow accumulated in Tampa, FL was 19 January 1977 when 0.2 inches of snow was recorded.  Overnight, into the morning hours tomorrow, there is a slight chance of snow falling in the Tampa Bay and the inland areas.  As the cold air continues to filter south, and the mid-level storm continues to induce showers over the area, it is possible for the inland areas to get cold enough to allow the precipitation to mix with, or even change over to, snow/sleet.  Areas along and near the coast will most likely remain too warm for snow/sleet to occur.   Either way, it will be interesting to watch this weather event unfold.