The ingredients for another flood event appear to be coming together as predicted for our region. The combination of increasing tropical moisture from the south, a stalled frontal boundary, and an approaching upper level disturbance will create an environment favorable for very heavy rainfall starting late Friday and continuing through Saturday.
1. Widespread rainfall amounts of 3 to 5 inches with isolated heavier totals. Isolated maximum totals of 6 to 10 inches are possible.
2. Flooding will occur first in low-lying and urban areas through Saturday with the heavy rain. River flooding will follow starting late Saturday night and continuing into next week.
The tropical disturbance near the Yucatan Peninsula will continue to move to the northwest and into the Southern Gulf of Mexico on Friday. While the potential for development of this system has decreased, a significant amount of tropical moisture is streaming northward across the Eastern Gulf of Mexico.
Whether this system organizes into a tropical depression or storm, the considerable influx of tropical moisture will combine with a stalled frontal boundary across the Southeast and approaching upper level energy to produce a period of heavy rainfall from Friday afternoon through Saturday across much of the region.
There remains some uncertainty with the location of the heaviest rainfall with this event, though several of the latest computer models appear to be indicating the greatest potential for flooding rainfall across Southeastern Alabama and the Florida Panhandle. One of these simulations appear at left. It is important to note that future simulations could shift the area of heavier rainfall elsewhere in the region, or even indicate lower rainfall totals.
Based on the latest model data forecasts, the image below shows average forecast rainfall from Friday through Saturday across the region. Note that as discussed above, isolated higher totals are possible.
Impacts: Rainfall of this amount will likely produce flooding of low lying areas and flood prone areas, particularly in urban areas like Panama City and Tallahassee. Bay and Washington Counties in the Florida Panhandle are especially vulnerable to flooding given the recent heavy rainfall these areas received in July.
River Flooding Concerns: River flooding will become an increasing concern by late Saturday and into next week, especially depending on where the heaviest rainfall ends up occurring. Florida Panhandle: If the latest forecast holds, the Choctawhatchee Basin from Newton through Bruce would easily return to minor flood stage late in the weekend with the potential for moderate flooding from Caryville southward to Bruce early next week. The Chipola has some capacity for heavy rainfall, but if rainfall amounts trend higher than expected, minor flooding would be a possibility at Marianna and Altha early next week.
For the latest river forecasts check out the AHPS page: http://water.weather.gov/ahps2/index.php?wfo=tae Summary:
** The potential is increasing for another heavy rainfall event Friday through Saturday. Rainfall amounts of 3 to 5 inches are possible with isolated heavier totals.
** Flash flooding is possible due to continued saturated soils. River flooding is also anticipated in the days ahead.
** While some slow development of the disturbance in the Caribbean is possible, whether or not this system develops, heavy rainfall is still anticipated across the region.