Hurricane Sally: The who, what, where, when, & why’s

WAFF 48 Noon Forecast

As Hurricane Sally nears landfall in the United States a lot of questions are becoming clearer. There was much uncertainty with the expected path and the strength of the storm but during the overnight hours last night both of those seemed to fall in line and we are more confident on where the storm will be moving and what impacts we will see here in the Valley.

The National Hurricane Center’s 1 PM Tuesday update showed the center of Sally located 100 miles directly south of the Mississippi/Alabama state line and moving to the northwest at a snail’s pace of 2 mph. With all of this said, what can we expect here in the Tennessee Valley?

Hurricane Sally's Forecasted Path
Hurricane Sally's Forecasted Path (Source: WAFF 48)
EURO Model - Potential Rainfall
EURO Model - Potential Rainfall (Source: WAFF 48)
EURO Model - Potential Rainfall
EURO Model - Potential Rainfall (Source: WAFF 48)
GFS Model - Potential Rainfall for the Gulf Coast
GFS Model - Potential Rainfall for the Gulf Coast (Source: WAFF 48)

What? What are the impacts from Sally? Depending on where you live in Alabama your impacts will range from minimal to moderate. Areas west of I-65 shouldn’t see much from this system other than some gusty winds of 15 to 25 mph. Farther east of I-65 is where the better threat is for heavier rainfall. Right now the amount of rainfall in the Tennessee Valley will all be determined by the path of the storm. A path that is farther to the north would bring us heavier rain into the Tennessee Valley. This outcome would lead to areas of 2 to 5 inches of rainfall for those east of I-65. If the path is further south, which is the predicted path, that would lead to much less rainfall and impacts here in the Tennessee Valley. In that scenario we would only expect to see less than an inch of rain in most communities and possibly no rainfall for areas close to and west of I-65. Both of these possibilities are pictured here. We will also have periods of stronger wind gusts of 20 to 30 mph over the next few days, but wind speeds should not be much higher than that.

Though our impacts will be more minimal to moderate, our friends in south Alabama won’t be as lucky. While many keep on eye on the category of tropical systems, a lot of the damage is due to the speed it is moving. Sally may be considered a “low end” hurricane only as a CAT 1, but the lack of speed is what will create the most damage in the form of flooding. Rainfall totals along the Gulf Coast could eclipse 20 inches of rain in some spots between Biloxi and Pensacola. There will also be the potential for stronger wind gusts near tropical storm (39+ mph) to hurricane (74 + mph) force. Severe weather potential is also much higher south of Montgomery with a spin up tornado threat as well.

Sally Severe Weather Threat
Sally Severe Weather Threat (Source: WAFF 48)

Where? Where will Sally go? Sally’s looks to make landfall between Biloxi, Mississippi and Pensacola, Florida before moving inland. As the storm progresses farther inland it will continue to turn right, or east, and head towards Montgomery and Macon, GA. If this is the path that pans out, that will limit much of impact here in the Tennessee Valley. We will really only see impacts here in North Alabama if the path of that storm is 50-100 miles farther to the north.

Hurricane Sally Likely Landfall
Hurricane Sally Likely Landfall (Source: WAFF 48)

When? When can we expect Sally to make landfall and when will see start to see effects here? With the speed of Sally being between 1 to 4 mph Sally won’t likely make landfall until mid to late Morning on Wednesday. The more likely timeframe is between 7am and noon. The storm is expected to speed up a bit as it moves to the northeast, moving over Montgomery around 24 hours or so after landfall. That is 150 miles in 24 hours.

Why? Why is this such a slow moving storm? Hurricanes follow the flow of their steering winds which are created by the easterly flow call the “trade winds” in the tropical latitudes. Once the reach the united states they are guided by the upper level flow of the jet stream or they are also guided by strong high and low pressure systems which pull or push these storms away. Right now, our jet stream is far north up towards the U.S./Canada border and there are no significant high or low pressure systems near Sally to help influence the flow of the storm, which is why basically it sits stationary.

You can get the very latest information on Hurricane Sally and all other Tropical activity on our 48 First Alert Weather App!

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