Official landfall is forecast to be very late Monday or early Tuesday, but Texans should prepare for tropical storm conditions late Sunday through early Monday.
Already, Beta is bringing tropical storm conditions to parts of the southwestern Louisiana coast.
A storm surge warning is also in effect from Port Aransas, Texas, to the Rockefeller Wildlife Refuge in Louisiana, where 2 to 4 feet of storm surge is possible.
"Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions," according to the National Hurricane Center (NHC).
The Texas State Operations Center has been activated to Level II, or Escalated Response Conditions, and the governor is warning residents to heed the advice of local officials.
Texas officials warn that rainfall, flash flooding and isolated tornadoes could occur with little to no warning.
"We will continue to closely monitor the storm and work collaboratively with officials to ensure our fellow Texans are safe," Texas Gov. Greg Abbott said.
A total of 8 to 12 inches of widespread rain is forecast, and isolated rainfall of up to 20 inches is possible from the middle of the Texas coast to southern Louisiana through Thursday.
The hurricane watch previously posted is discontinued, but Beta is chugging along at a dangerously sluggish 5 mph to the west-northwest, having slowed Saturday morning from 12 mph.
It is packing sustained winds of 60 mph, about 140 miles southeast of Galveston, Texas, and the NHC's reconnaissance aircraft has found no change in strength.
But at such a slow pace, the storm is still dangerous.
By comparison, an average human walks around 3 or 4 mph. Hurricane Sally made landfall at 3 mph. Florence made landfall at 6 mph and Harvey at 7, but both storms slowed very quickly after landfall and triggered tremendous flooding.
Beta is battling a good amount of shear and dry air in the Gulf of Mexico which is keeping the intensity of the storm from increasing.
Having a "high shear" environment prevents a storm from intensifying. A "low shear" atmosphere environment is favorable for the tropical system to develop further and intensify.
The shear is also making the storm very asymmetric, and the bulk of the rain and strongest winds are located to the north and northeast of the center.
A historic Atlantic Hurricane season
Beta is named after the second letter in the Greek alphabet.
Alpha was named Friday, and a few hours later, Tropical Storm Beta was named in the Gulf of Mexico.
The NHC ran out of names for the 2020 Atlantic Hurricane season and began drawing from the Greek alphabet for only the second time in recorded history.
The other time was in 2005, when the season produced so many storms it exhausted the season's list of 21 names.
The Atlantic hurricane season officially runs from June 1 through November 30. With two months remaining, 2020 could easily surpass the record set in 2005.
The season has produced almost twice the average number of storms with 23 named so far. The average hurricane season produces 12.
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