The Groundhog may have predicted an early spring by seeing his shadow, but warmer weather isn’t the only thing Floridians want. It’s rain that the Sunshine State is in need of. Gainesville has a rainfall deficit of more than three inches so far in 2013. And outside of one significant rainfall event on December 10, rainfall has been largely below normal since the rainy season ended in early October. The Climate Prediction Center’s Drought Monitor Index reveals abnormally dry conditions have developed across all of North-Central Florida and their forecast calls for this to continue worsening through early spring. However, WRUF is forecasting a change in the upper-level winds that may provide some temporary relief to the peninsula by the middle of the month. This pattern transition is expected to unfold by the end of the upcoming work week.
CURRENT DRY PATTERN
Temperatures have been on quite a roller coaster ride lately. We’ve had long stretches of unusual warmth, followed by sharp drops and a frost or freeze. The fronts that have ushered in the colder air have come through mostly dry. This has been largely a product of the position of high pressure systems that follow the fronts. When the clockwise circulation center is to our west or directly overhead, the northerly winds shut down the ability for the Gulf of Mexico to be a player with the next weather system. Significant moisture is shunted south and doesn’t have time to move back northward before the next cool, dry air mass sweeps in. Rainfall along nearly every front since the beginning of the year has only amounted to less than two tenths of an inch.
Upper-level winds are expected to shift slightly this week, sending the high pressure systems on a more easterly trek into the Mid-Atlantic states. The difference in the orientation of the high with respect to Florida is significant. Rather than a northerly wind, the flow will become more aligned out of the east or southeast. A wind such as this off of the Atlantic Ocean is usually not as cold and filled with a little more moisture. Furthermore, as the high slides more off to the east, the flow can veer more out of the south or even southwest. This allows Gulf of Mexico moisture to be pulled further northward and increases the opportunity for precipitation with the next storm system. The longer the Gulf remains available before each front or storm system, the greater the chance for significant rainfall. The strength and trajectory of the upcoming systems will also play a role in how much or how heavy the rain will be.
THE BOTTOM LINE
The specifics on the timing and intensity of future rainfall events is still in question, but our exclusive 10-Day Forecast does show increasing opportunities for some much-needed drinks of water by week’s end. It may take about a week for this pattern shift to pay off. Longer range forecast data does suggest the potential for stronger weather systems to possibly move into the state by mid-month, but as always we must remind you that details on amounts and timing won’t be available until a few days out. We will keep you updated right here, on WRUF-TV, or online @GatorWeather with the very latest as this pattern transition unfolds.