Cristobal weakened to a tropical depression Thursday while it slowly drifts east southeast and brings flooding rains over Mexico. It is expected to turn toward the north, moving back over the Gulf of Mexico, strengthening and moving toward the US Gulf Coast by the weekend.
Thursday morning, the former tropical storm, with sustained 35 mph winds and gusts to 45 mph, was moving at 3 mph, almost the pace most people walk.
This slow movement is allowingCristobal to unleash dcopious amounts of rain across Central America. Some areas could see rainfall amounts measured in feet, leading to life-threatening flooding and mudslides.
Storm rainfall totals with this system could leave isolated amounts of almost 3 feet of rain — 35 inches — in some areas across Guatemala and El Salvador.
In Mexico, isolated storm total rainfall amounts of 2 feet of rain have and will fall in the Mexican states of Campeche, Quintana Roo, Tabasco, and Yucatan.
“One of the most impactful effects of climate change on tropical systems is increasing the rainfall they can dump, which can lead to flash flooding,” CNN meteorologist Brandon Miller says.
We are seeing this with Cristobal.
“As ocean and air temperatures warm, it allows more moisture to be held in the atmosphere, which can increase the rate at which rain falls,” Miller says.
Cristobal forecast to strengthen as it moves toward the US
“A turn toward the east and northeast is expected later today,” the National Hurricane Center (NHC) forecast Thursday morning. The center of the storm will move over eastern Mexico during the day Thursday and overnight.
The center of Cristobal should re-emerge over the Gulf of Mexico on Friday as it begins to track north and strengthen.
“A subsequent northward motion should occur through Saturday,” the NHC said.
“Most of the computer model guidance shows Louisiana as the likely target of landfall either late Sunday or into Monday,” CNN meteorologist Dave Hennen says.
Sea surface temperatures across the Gulf of Mexico are warm enough to support the strengthening of the storm. But this is just one ingredient a tropicaldepression needs to become a hurricane.
Wind shear — the change with winds speed and direction with height — needs to be low. There also needs to be ample moist air throughout the environment.
“A combination of wind shear and dry air being injected into the storm will likely limit Cristobal’s intensity,” says Hennen.
There is still a 50/50 chance the system could form into a hurricane. Either way, heavy rainfall will affect the Gulf Coast states.
“It’s still too early to tell which areas along the Gulf Coast will be most severely impacted,” Hennen says. “But flooding will likely be the biggest threat.”
Flood watches have already been issued for portions of Louisiana and Florida, as tropical moisture begins to stream in.
“Impacts from the storm will likely be felt far away from where the center eventually makes landfall,” says Hennen.
This means everyone along the coast should pay attention to the storm and the conditions where they are.