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Tropical cyclone Alberto will move across the Gulf of Mexico and make landfall in the Florida Panhandle later on Monday.

Alberto will impact several states across the Southeast, but affect Florida the hardest with damaging winds and widespread heavy rain. Across the Panhandle a storm surge of up to 2-4 feet is expected around the time of landfall.

Details on Alberto

Alberto will track across the warm waters of the Gulf of Mexico through Monday. Environmental conditions will favor some strengthening as the storm tracks toward the Florida Panhandle.

Landfall is expected between Mobile, Alabama and Apalachicola, Florida Monday afternoon or evening. A storm surge of up to 4 feet is expected near and just to the east of Alberto’s center.

The circulation around Alberto is large which means the wind field around the storm is also quite large. Consequently, tropical storm force winds of 39 mph or greater could extend up to 120 nautical miles from the center of Alberto.

 Alberto will also bring an abundance of tropical moisture northward from the Caribbean and Gulf of Mexico. The tropical moisture associated with Alberto will interact with a frontal boundary over the mid-Atlantic to bring a widespread area of heavy rain through Wednesday.

The heaviest rain is expected near and just east of the track of Alberto where 4-8 inches is expected. A second area of heavy rain is expected across southern Florida.

Across the Carolina’s and the mid-Atlantic, the rainfall expected will be due to tropical moisture moving in from the Atlantic Ocean and not directly from Alberto.

The wind risk from Alberto will diminish Tuesday night and Wednesday, but areas of heavy rain could continue across the Ohio Valley into Thursday.

 

We’re monitoring a tropical disturbance currently hovering over the western Caribbean, just east of the Yucatan Peninsula. It’s part of a train of tropical moisture pumping up into the eastern U.S. Heavier than normal rainfall has been occurring for more than a week and is likely to continue for another week or more. But will there be the added threat of tropical storm development?

 

 

Model guidance is split on how this system will evolve. They agree on the possibility of some tropical development, despite how early we are in the season. In fact the hurricane season doesn’t even start until June 1st. However, a few tropical storms have been known to develop earlier. Some of the models turn the system towards the northwest and the central Gulf; others bring it more northeast towards Florida and the Carolinas.

Regardless of whether or not the system intensifies to tropical depression or storm status, the moisture associated with the system will enhance already heavy rainfall in the southeast. The map below from NOAA’s Weather Prediction Center shows forecast rainfall amounts through the next seven days. You can see the heaviest rainfall amounts of 6-10 inches (150-250 mm) likely to impact coastal zones and the Florida peninsula.

 

 

A muggy, wet summertime pattern has set up across much of the eastern half of the U.S. over the past several weeks. Persistent southerly flow has been pulling moisture up from the Gulf of Mexico and the tropical Atlantic. The result has been two to four times the normal precipitation amounts from Florida up to the Mid-Atlantic since late April (see graphic below courtesy the Climate Prediction Center). Long-term trends and model guidance indicate this pattern will continue through much of the summer.

 

 

One of the prime mechanisms controlling long-term climate forecasting is the ENSO (El Nino Southern Oscillation), variations in sea surface temperatures across the Pacific basin. Currently neutral, the ENSO will be trending more positive and could be designated an actual El Nino later this year. In the shorter term, the Madden-Julian Oscillation (MJO), a globe-circling wave of clouds and rain, will remain active. This pattern is sometimes associated with increased tropical cyclone activity in the Atlantic basin, which would tend to support the idea that rainfall will be above normal. Global models have been tending to generate cyclones in the longer range (two weeks out). Even if cyclones don’t develop (it’s a bit early to reasonably expect them), an open tropical moisture tap can be expected to continue.

 

 

The one- to three-month forecasts above reflect the expectations for continued warm, wet weather. Unfortunately, this enhanced rainfall will continue to miss the extreme drought now stretching from the Four Corners region into the southern High Plains (map below).