Bertha remained a weak, disorganized and lopsided tropical storm Wednesday morning, with its largely innocuous center swirl – absent any organized thunderstorms – sliding westward toward southeastern Louisiana.
The local National Weather Service office in New Orleans may have summed up Bertha best early Wednesday, as one of its meteorologists wrote in its area forecast discussion:
“Abnormal tropical storm conditions is putting it lightly. I for one have never seen a tropical storm warning and a heat advisory/warning for the same time frame in the same area. But here we are.”
Despite a track that takes the center through parts of south Louisiana today, a sunny start to the day with mostly dry conditions and breaks in the clouds – even as the center of Bertha passes through – will allow temperatures to soar, with feels-like temperatures climbing to nearly 115 degrees for much of southern Louisiana and parts of coastal Mississippi. As a result, extreme heat warnings are in effect alongside tropical storm warnings today.
It’s an unusual paradox but for a very unusual storm. While tropical storm warnings indicate the likelihood of winds exceeding 38 mph, in this case that’ll be mostly in gusts, and areas in South Louisiana under a tropical storm warning will mostly see a breezy day without any consequential rain.
The exception could be areas farther south and along the immediate coast – such as in the long finger of Plaquemines Parish that juts into the Gulf – where minor, localized flooding is possible, especially with higher than usual tides. The overall impact from Bertha will be minimal at best today and Thursday as it scrapes along the northern Gulf Coast, with its remnants moving inland over eastern Texas later tomorrow.
Copious rainfall…over water
Bertha has been a prolific rainmaker, but over water. As we’ve discussed all week (and last), relentless wind shear has blown off all of Bertha’s organized storminess to the south of its center and over the Gulf.
Radar estimates indicate rain totals topping nearly two feet over parts of the northern Gulf, and a marine station atop an oil platform located about 140 miles south of Grand Isle, Louisiana, has reported almost 11 inches of rain since yesterday morning.
Over land, however, and near and to the north of Bertha’s center, rainfall totals have been unremarkable and manageable, with only a few inches at most reported so far.
This will continue to be the case today and tomorrow, perhaps even more so as wind shear ramps up further and pushes thunderstorms farther offshore. The National Weather Service forecasts only a low (aka marginal) risk of flash flooding in isolated spots (flash flood threat level 1 of 4) through Thursday for southern Louisiana and areas east, with only spotty bands of showers expected around Bertha’s center.
What are the chances Bertha reforms farther south and strengthens en route to Texas?
Slim to none. While there’s an outside chance Bertha’s exposed center unravels and reforms farther south, where it might be less affected by the firehose of shear, even in that case it’s unlikely to have the room it’d need to re-strengthen much before moving inland over Texas on Thursday.
The odds of it surviving and making a run as a hurricane is less than 1%, according to Google DeepMind’s 1,000-member ensemble system. In other words, don’t bet the farm on it.
Far and away the most likely scenario is a gradual weakening as Bertha’s center gradually disassembles today and tomorrow.
Mum’s the word elsewhere through July
Elsewhere, we’re seeing nothing on the horizon across the Atlantic basin through July and into the first week of August.
Seems like another dry-eye storm - I guess it'll pass on to/by Houston - there seem to be a lot of power outages around here that match up to where the ai data centers are - we've got extreme heat today (like everyone) & I guess this tropical storm won't really help cool down a super-strained grid - what a weird trade off - lopsided dry pseudo-storms vs extreme heat 😶
Ty Mr. Lowry 🌺