Residents of southern Texas need to start getting ready now for a major impact from Harvey. The storm fell apart in the western Caribbean last weekend, but wary weather watchers know this time of year not to count out any storm wafting over warm waters.
Harvey re-emerged over Mexico’s Yucatan peninsula Wednesday morning and will likely strengthen and head for Texas, as a bevy of computer models analyzing the system for the past few days have hinted. Very warm water in the southern Gulf of Mexico and weak upper-level winds will help Harvey strengthen rapidly. The current track from the National Hurricane Center keeps it a tropical storm, making landfall near Corpus Christi by Friday morning – less than 48 hours:
Even though the forecast keeps Harvey a tropical storm, hurricane watches are posted from Galveston to Brownsville. Harvey could intensify and batter the coast with those destructive winds. However, like any tropical threat, Harvey’s impact won’t just be along the coast and not just where it makes landfall.
While there may be great uncertainty regarding Harvey’s uncertainty, there’s strong model consensus that this storm will literally park itself in southern Texas and Louisiana well into early next week. So, flood-weary residents of Houston, Lake Charles and possibly even the Big Easy should be preparing for life-threatening flooding that will last for days.
Here’s an early projection of expected rain in the region through Wednesday:
That means 10″-15″ for Houston/Galveston, 8″-12″ for Lake Charles, and possibly 6″-10″ for Baton Rouge/New Orleans. So while these areas will dodge high winds, they won’t be able to do anything about the rising flood waters.
In addition to the falling rain, the rise of water from the Gulf, churned by the storm will bring a storm surge threat along coastal areas along with significant beach erosion, particularly if the storm lingers as forecast.
Finally, the hurricane center provides this useful outlook for the onset of the arrival of tropical storm force winds (greater than 39 mph).
This is a good reminder for people living far from the center of the storm that they will have an impact many hours before landfall.
It’s critical that when it comes to tropical threats, we shift our focus to consider the multi-faceted impact of any storm. If we focus on the “snapshot” of any one image, we miss the “movie” of a storm’s evolution.
If evacuations are ordered, coastal residents would do well to heed them, even if Harvey doesn’t become a giant wind storm. The threat of flooding could leave whole neighborhoods submerged for days. People in the path should realize that, along with power outages, if they plan to ride it out.
Another thing to keep in mind is the threat of isolated tornadoes as the swirling storm bands crash ashore. These often strike suddenly so be sure you have an active WeatherCall subscription so you’ll know if that danger heads your way. If you already have this service, consider modifying your account to give you alerts for severe thunderstorms. Often, these warnings result in tornado damage because there may not be time to upgrade to a tornado warning due to how quickly a storm is developing.
Above all recognize that these projections can and will change, but as I said earlier – this is a movie and right now, we’re getting the coming attractions. Hopefully, what people in South Texas see now incents them to quickly prepare.