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Will Beta be another Harvey? Not likely. Here’s why.

While Beta poses a serious flood threat to the Texas coast, it is not likely to become a repeat of Harvey.
While Beta poses a serious flood threat to the Texas coast, it is not likely to become a repeat of Harvey.

HOUSTON – Since Hurricane Harvey, Southeast Texans have been hyper-sensitive to potentially catastrophic flooding from another tropical system, and with good reason! When a storm like Beta comes along, then, the first question that comes to mind for many people is, “Will this be another Harvey?”

The simple answer to this question is NO. We do not expect Harvey-level flooding from Beta, and here are the reasons why:

Dry Air

The beautiful fall weather we are experiencing prior to Beta’s arrival comes from the fact that we’ve got a very dry air mass over Texas and the extreme western Gulf of Mexico. This dry air is being drawn into Beta’s circulation, causing the storm to be very off-balance, or lopsided. It is depicted very well on water vapor satellite imagery. The orange coloring to the left (west) shows dry air. Dry air is stable. It lacks moisture to fuel thunderstorms. If it gets drawn into a tropical system’s circulation, it will keep it from intensifying or even cause it to weaken.

Dry air intrusion will keep Beta from strengthening.
Dry air intrusion will keep Beta from strengthening.

The infrared satellite imagery below shows storms to the northeast of the center of Beta with dry, peaceful skies to the west and south. It is a perfect illustration of a less-than-healthy system. A healthy, intensifying storm would look more symmetric, with thunderstorms wrapping all the way around the center of circulation.

Stormy weather is limited to the east side of the storm.  The storm is asymmetrical and unbalanced, therefore unlikely to intensify.
Stormy weather is limited to the east side of the storm. The storm is asymmetrical and unbalanced, therefore unlikely to intensify.

Wind Shear

The upper-level winds over the western Gulf are somewhat strong, and strong upper-level winds inhibit hurricanes. The southwest wind aloft over Beta is working, in concert with the dry atmosphere, to keep the storm from getting stronger. Wind shear will continue to be somewhat of a problem for Beta as it works its way toward the Texas coast.

Strong upper level winds from the southwest are hindering Beta's development.
Strong upper level winds from the southwest are hindering Beta's development.

Forecast Model Predictions

Before Hurricane Harvey hit in 2017, computer forecast models were generating out-of-this-world rainfall predictions, such as 20 to 50 inches of rain. The likes of which we had never seen before. We knew before Harvey hit that it would have catastrophic potential. The current rainfall predictions for Beta are much lower, largely based on the factors outlined above.

While we still expect copious amounts of rain along the coast, our estimates are closer to 8 to 15 inches over three days rather than 40 to 60 inches over five days.

The American and European forecasts for rainfall accumulation are closer to 10 inches near the coast for Beta as opposed to 20, 30, 40 or more inches as with Harvey.
The American and European forecasts for rainfall accumulation are closer to 10 inches near the coast for Beta as opposed to 20, 30, 40 or more inches as with Harvey.
Rainfall will be heaviest offshore and along the immediate coast.  Rainfall totals should taper off quickly inland.
Rainfall will be heaviest offshore and along the immediate coast. Rainfall totals should taper off quickly inland.

Bottom Line:

Beta is not expected to be a repeat of Harvey. Harvey was a Category 4 hurricane when it made landfall and lingered over southeast Texas for five days with almost unlimited atmospheric moisture to draw from. Beta will be weaker, will have less moisture to draw from, and will only be hovering nearby for three days.

That said, we can’t let our guard down with Beta. It will be lingering long enough to present a serious flood threat to the coast, so we need to prepare accordingly:

  • Stay informed with the weather forecast as it changes in the coming days because it will change. Slow-moving storms are notoriously difficult to predict. Tune in to Channel 2 and Click2Houston.com for updates.
  • Be sure to follow any guidance from local officials regarding evacuations and other preparations leading up to Beta’s arrival.
  • Make sure you have your hurricane plan in place and be ready to put it into action if you need to!

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