Tropical Storm Harvey could be making a comeback. If it does, it could possibly even become a hurricane.
Harvey initially formed just east of the Windward Islands, in the Caribbean Sea. It reached tropical storm status from August 17-19, but dissipated over the eastern Caribbean after encountering unfavorable environmental conditions.
After moving over the Yucatan Peninsula Tuesday as a tropical wave, the remnants of Harvey are now emerging into the western Gulf of Mexico — and more importantly, into an environment that is favorable for development.
Detailed forecast
Will it become a tropical storm again? Will it become a hurricane? How strong will the winds be? And how significant will the storm surge be?
These are all questions that will be answered over the next few days. As of Tuesday evening, the National Hurricane Center says there is nearly a 100% chance of Harvey redeveloping.
A few days ago, forecast models largely showed the remnants of Harvey moving into Mexico.
However, over the past few days, the majority of our forecast models have trended northward and most are now showing the storm reach Texas.
It’s too early to say where in Texas, but a few days ago the risk of Harvey making it north of Brownsville was fairly low. Now that is no longer the case.
This is significant for many reasons, but most importantly, the farther north the storm travels, the greater distance to landfall. And greater distance equals more time to strengthen over the extremely warm waters of the Gulf of Mexico.
With the expected slow trajectory across the Gulf of Mexico, Harvey shouldn’t reach the coast until Friday or perhaps even early Saturday. This is plenty of time to allow for the possibility of Harvey becoming a hurricane.
Should Harvey become a hurricane and make landfall in Texas, it would be the first hurricane to do so since Ike in 2008. According to Phil Klotzbach, a hurricane research scientist at Colorado State University, the longest streak without a hurricane landfall in the state of Texas is 11 years (1855-1865).
Flood threat
While there are many questions about the strength and impacts, one thing is more certain: flooding is big concern.
Inland flooding is often one of the biggest threats of a landfalling tropical system, but rainfall amounts increase exponentially when the storm moves at a slower speed.
The National Hurricane Center is already saying “the system is likely to slow down once it reaches the coast, increasing the threat of a prolonged period of heavy rain and flooding across portions of Texas, southwest Louisiana, and northeastern Mexico into early next week.”
Again, the specific locations of extreme rainfall and flooding are impossible to project before the storm even develops. However, forecast models, such as the one below, are showing the potential for widespread areas of six inches of rainfall.
10-15″ is likely in a few of the hardest hit areas and extreme amounts of over 20″ are not uncommon with slow-moving tropical systems.
While it has been nine years since Texas last saw a hurricane, the state is no stranger to devastating flooding from tropical systems. In 2001 Tropical Storm Allison was a multibillion dollar disaster for the state, specifically Houston. Allison became nearly stationary for days, dropping more than 30 inches of rain across portions of the city. To this day, Allison is the only non-hurricane to have its name retired.
