Heaviest Rainfall Threat from PTC1 Shifting Southwest
The heavy rainfall threat for the northeast Houston area from PTC1 (Potential Tropical Cyclone #1) has shifted southwest somewhat today. While the storm takes its time getting organized, high pressure from the eastern US is building into the Houston area. That’s squeezing the heaviest rains toward the coast and the Rio Grande Valley.
Meanwhile, the National Hurricane Center warns of a second storm forming next week exactly where PTC1 is forming now. But it will likely head north, not west.
Heaviest Rainfall from PCT1 Shifting Southwest
Over the weekend, early predictions suggested heavy rains would arrive in the Lake Houston Area on Monday. Monday’s predictions suggested Tuesday. And now Tuesday’s predictions say the Lake Houston Area might get 1-3 inches of rain during the next three days.
The National Weather Service (NWS) now predicts PTC1 will produce rainfall totals of 5 to 10 inches across northeast Mexico into South Texas. Maximum totals could approach 15 inches.
This rainfall will likely produce flash and urban flooding along with new and renewed river flooding.
NWS also predicts the broad circulation of PTC1 could produce extreme rainfall in Central America. Totals could average 10 to 20 inches with maximum amounts of 25 inches. Areas most affected include the Pacific coast of far southern Mexico, southern Guatemala, much of El Salvador, western Honduras, and far western Nicaragua.
Here’s what the storm looked like earlier today from space.
Landfall in Mexico
As of 4PM CDT Tuesday, NWS predicted PTC1 would make landfall in Mexico sometime within the next 24 to 36 hours as a tropical storm. They currently give it an 80% chance of formation.
At present, the storm exhibits wind speeds approaching tropical storm strength (39+ MPH). Tropical storm conditions could begin tonight or Wednesday along portions of the Texas coast south of San Luis Pass.
Tropical storm force winds extend outward 415 miles north of the center.
National Hurricane Center
So focus less on the track and more on the impact.
The National Hurricane Center (NHC) warns, “Regardless of the exact track of the low, this system will have a large area of heavy rains. Expect moderate coastal flooding and tropical-storm-force winds well north of the center.”
Moderate coastal flooding is likely along much of the Texas Coast through midweek.
If PTC1 becomes a tropical storm, its name will be Alberto.
Double Trouble?
NHC’s website showed something unusual today. One possible tropical system could develop within the area vacated by another. Within days of each other!
NHC gives a 20% chance of the second storm developing in the yellow area with the red X.
But instead of moving into Mexico, they predict the second storm could move northward. That could make it a direct threat to Houston.
So check NHC’s weather forecasts daily during hurricane season. As PTC1 proves, weather can change quickly.
Posted by Bob Rehak on 6/18/24
2485 Days since Hurricane Harvey
