4 Expert Tools to Track the First Tropical Storm of the Season
National Hurricane Center Director Ken Graham often says there is no “just a” category. He’s referring to the misnomer that if a storm is just a tropical storm, it won’t cause damage or harm.
The same could even be said about an unnamed tropical system, such as the one that moved across South Florida this weekend. The National Weather Service predicted “major” flooding from Naples to West Palm Beach, including greater Miami where 8 to 12 inches of rain was likely over a 48-hour period. Tornadoes were also possible as the circulation from the system moved across the peninsula Friday night and Saturday.
The flooding was significant in downtown Miami early Saturday morning, as streets were turned into ponds and rivers from relentless bands of heavy rain.
A tropical storm may not get the attention a hurricane does, but emergency managers and insurance adjusters know all too well they can cause damage or even be life-threatening if residents and business owners are not prepared properly.
Assess Your Flood Risk 48 Hours in Advance
The most significant hazard from a tropical storm is flash flooding. The disorganized nature of these storms can make it difficult to pinpoint where the heaviest rain may fall. And it’s often not near the center of the storm. A high-resolution forecast model can help.
When a tropical storm is in its formative stage or weak, it often moves much slower than a hurricane. As a result, rainfall totals can sometimes be greater than what a hurricane produces, but usually in a more localized way.
Detect Rotation for Possible Tornadoes
The radar can sometimes be full of greens, yellows, and reds as tropical storms come ashore. Embedded in those rain bands might be areas of rotation that quickly spawn a tornado. Using an advanced data product, such as one that only shows rotating winds, provides a clearer picture of where to watch and respond.
Thankfully, there were no tornado warnings or reports of tornadoes from the tropical system that moved through South Florida at the time of this post.
The comparison above was captured during a severe weather event on March 30, 2022. Notice the difference between a standard radar view and one that offers clarity on solely the rotating part of an outer rainband.
Get Advanced Notice of Imminent Flash Flooding
Flash flooding is one of the top weather-related killers in the world. This freshwater flooding has been responsible for more than half the deaths from tropical storms or hurricanes in the U.S. over the past 30 years.
Baron has a newly derived real-time risk dataset that can provide accurate and advanced notice down to the street level where a life-threatening event is likely to occur. The snapshot below illustrates the detail the product can provide on where flash flooding is most likely within a two-hour window.
The guidance shows the threat of flash flooding over the next two hours with a simple three-tiered risk level: Elevated, high, or very high. The model uses a high-resolution 23-yearlong historical dataset of soil-moisture evolution and runoff, then matches it with recent rainfall rates and short-term modeling to pinpoint where an extreme event is likely to occur. You can read more on this product from our case study on the flash flood event earlier this spring in Birmingham, AL.
Monitor Rainfall Amounts in Realtime
The rainfall can add up quickly during a tropical event. And there can be significant outcomes if it all comes down over a short amount of time versus being more spread out across several hours. Datasets on historical rainfall accumulations at multiple iterations can clear up where the rainfall rates are problematic versus just a nuisance.
Storm total rainfall accumulations from the tropical system exceeded 12 inches in parts of Southwest Florida, but the most problematic flooding occurred in the Miami metro area where more than 8 inches fell in 24 hours.
The data products shared in this story are available to developers in the Baron API or for use by emergency response personnel in the Baron Threat Net web application. Baron experts will also be standing by for decision support all hurricane season long.