TAMPA, Fla. — I get this question a lot, especially this time of year... why is the temperature at my house different than the one you are showing on Spectrum Bay News 9?
The answer is it's because we have micro-climates in our region where temperatures can vary largely over a very short distance. Many regions around the country experience 'micro-climates', but we tend to have even more variation in temperatures due to our unique position between the Atlantic Ocean and the Gulf of Mexico.
When cooler, drier air moves in from the north in the winter it can feel more like Georgia instead of southern Florida around here.
Have you ever noticed how our morning lows are where the biggest differences are? It can be near freezing in some spots while its in the 50s in others...all in the same morning! The reason for that is because the colder air can get 'trapped' in low areas away from coast. So at night after the warmth of the sun radiates away from the ground the cold air is left behind resulting in cold morning lows.
This is referred to as 'radiational cooling'. This cold air tends to always settle in the same spots due to the unique orographic layout of our area. For example, there are hills combined with low lying valleys that stretch from Citrus, Hernando, and Pasco County all the way down into eastern Hillsborough and western Polk County. This tends to act like a funnel for the cold air to settle into those areas. It just happens to be close to the I-75 corridor.
You've probably seen us talk numerous times about these 'colder' areas. Some of the coldest locations tend to be near Inverness in Citrus County, Brooksville in Hernando County, Zephyrhills in Pasco County, and Brandon-Valrico in Hillsborough County.
If you draw a line on the map between those locations you will get an idea of that colder funnel area that I'm referring to. This is very noticeable in the attached images on this page.
Locations near the coast tend to be milder due to the influence of the warmer Gulf waters. Locations right around the Bay are milder for the same reason. However, the interesting part is temperatures can drop off quickly a few miles away from the water. We've seen locations in northern Pinellas County between Clearwater and East Lake sometimes get 15 degrees colder than Clearwater Beach.
It's obviously warmer near the water in places like downtown St. Pete and Bradenton, but the temperatures can be drastically cooler farther inland. Locations just east of I-75 between Sun City Center, Parrish, and Lakewood Ranch are known for being much cooler on winter nights.
In Polk County the temperatures can be heavily influenced by the numerous lakes. One of the most famous examples is the Winter Haven gauge that is on the west side of the regional airport. It's surrounded by 5 lakes! Due to this very interesting location, the gauge tends to be much warmer than other locations in the county as the lakes tend to act like a warming blanket that surrounds the airport.
However, other locations like Polk City, Lake Wales, Mulberry, Kathleen, and the west side of Lakeland are all cooler. Something also very interesting is the Mid-Florida Ridge (also referred to as the Lake Wales Ridge) that runs through eastern Polk County. This ridge will sometimes act as an orographic border for cold air to stay west of it, providing for wide temperature variations across Polk County.
We talk about these differences a lot in the winter time. If you watch our weather forecast at :19 minutes past the hour, you'll notice we always provide a county-by-county forecast. This is where we show you more detailed forecasts and those differences on the local level.
If you just quickly tune in to our station and see a temperature on the corner of the screen and wonder why your gauge is different from that number, now you know why.
This is also a good time to remind everyone that if you notice different temperatures on your phone app, this shows the limitations of automated phone apps versus a real human forecast. As a meteorologist, it's my job to understand these variations for our region, explain them, and forecast them.
With the advent of phone apps unfortunately there's a lot of incorrect weather information floating around out there. A weather app is meant to give a general idea and can be a good starting point for basic information, but isn't intended to be the complete source of accurate information.
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