Less than 24 hours before landfall, Major Hurricane Willa has its eyes set on Mexico’s west-central coast. This category 4 storm is expected to produce life-threatening storm surge, incredibly strong winds, and dangerous flash flooding. Mexican states Sinaloa and Nayarit can expect devastation, after only having a few days notice to prepare. After landfall, this storm’s remnants will continue to carry large amounts of tropical moisture, ready to dump it on anything in its path. And, in its path, is Texas.
Consensus shows Willa continuing northeastward, heading right for Texas. A shortwave trough will slide in aloft over the Four Corners tonight, and slowly propagate eastward. Counter-clockwise flow around this trough is what will guide Willa’s remnants Wednesday into Thursday. Even as winds die down after landfall, large amounts of tropical moisture remain near the core of this undead cyclone. This will bring the heaviest rains to parts of Texas that have already been drenched this month with uncharacteristically high rainfall for October.
Texas has been experiencing almost nonstop rain since early last week. San Antonio and parts of Austin have seen near record-breaking rainfall. Already about 10″ above average for the year, 2018 could be in the top 20 wettest years for San Antonio. Up to 4 more inches could be seen from this storm, causing already saturated soils to easily flood. Austin will most likely see slightly more rain than San Antonio, but is still only a few inches above average for the year in total. Still, October is looking to be one of Austin’s wettest months, most likely landing somewhere just before 20th place. As the system moves across the TX and LA Gulf Coast, precip will remain high, soaking everything in its path. Closer to 5 inches can be expected closer to the coast, where warm Gulf water is more readily available for this system.
The remnants of Willa are expected to reintensify along the Gulf coast later this week. Following flow aloft, Willa’s intensification and track will be aided by convergence from a low-latitude jet streak. This jet, caused by a strong temperature gradient between cold Arctic air and warm tropical air, will follow the cyclone and, ultimately, bring it to the East coast. Tracking up the East coast, Willa could continue to intensify after reaching the frontal boundary of this Arctic air mass, and possibly become the first Nor’easter of the season. If this scenario does occur, this storm would bring mostly rain to the Northeast. However, depending on the timing and intensity of the incident Arctic air, mixed precip and even snow is possible for New England and upstate NY. We will continue to update on the status of Willa, and its potential impact on the Northeast.