Tropical Storm Bonnie forms and rolls toward Central America

“Heavy rains are likely in parts of Nicaragua and Costa Rica today through Saturday. Areas with life-threatening flash floods and mudslides are expected,” wrote the National Hurricane Center.

Bonnie is one of three tropical system forecasters they have monitored. A fault that formed in the western Gulf of Mexico has already moved across upper Texas coast and southwest Louisiana. Though it hasn’t organized enough to become a named storm, it has discharged torrential rain north of Houston.

A third disturbance hot on Bonnie’s heels has a 10 percent chance of becoming a tropical depression or storm during the weekend. But it’s expected to bring gusty showers Friday through Saturday across the Windward Islands, which bridge the Atlantic and Caribbean.

Bonnie, the second named storm of the Atlantic hurricane season, formed 16 days ahead of the average. The National Oceanic and Atmospheric Administration is forecasting a busier-than-normal season — with 14 to 21 named storms, including six to 10 hurricanes and three to six major (Category 3 or higher) hurricanes. The Atlantic season typically peaks in late August and September.

Tropical Storm Bonnie details

Bonnie is a minimal tropical storm with winds of 40 mph. The Hurricane Center is forecasting a modest strengthening ahead of landfall when peak winds could reach 50 mph.

While such winds could be quite gusty and cause downed trees and power outages, the main danger is heavy rains as the storm crosses Central America.

The Hurricane Center is projecting 4 to 8 inches of rain and localized amounts up to a foot in Nicaragua and Costa Rica.

Bonnie could also create a small ocean surge — or soar in water from 1 to 3 feet over normally dry land near and north of where its center meets land.

After crossing Central America, Bonnie is expected to surface in the Pacific Ocean, where it is expected to gain strength and potentially become a hurricane early next week. However, no land is expected to be threatened.

According to tropical weather researcher Phil Klotzbach, Bonnie is something of a rarity — among one of six named storms that form in the Caribbean in July.

Texas-Louisiana tropical rainstorm

Meanwhile, the disturbance that has formed over the western Gulf is bringing a flood threat from around Galveston, Tex. to Lake Charles, La. on Friday.

Flood monitoring covers this entire zone until the afternoon or evening. As of noon, the heaviest rain had moved north of Houston and Galveston but soaked the Golden Triangle area, which includes Beaumont and Port Arthur, where flash flood warnings are in effect until 3:45 p.m

“Between 4 and 8 inches of rain has fallen,” wrote the National Weather Service. “Additional rainfall amounts of 1 to 3 inches are possible in the warning area. Flash flooding is already occurring with multiple reports of road flooding from Port Arthur and the surrounding area.”

The Weather Service issued a special bulletin warning that precipitation rates could at times exceed three inches per hour.

Radar showed torrential rain between Beaumont and Lake Charles on Friday midday, but forecast models say the downpours will gradually ease into the evening.

While up to 8 inches had fallen in the Golden Triangle region, most of Houston had seen about a tenth of an inch. The rains bypassed much of inland Texas, which is suffering from extreme drought and unrelenting heat.

San Antonio had triple-digit heat for 17 days in June. The norm is two.