Context: Recently, Tropical Storm Cristobal made landfall in Mexico’s Gulf coast state of Campeche, dumping heavy rain on the already soaked region ahead of an expected eventual turn toward the United States according to the US National Hurricane Center.
Key Points

• Tropical Storm Cristobal formed in the southern Gulf of Mexico on Tuesday, threatening to bring deadly flooding in parts of southern Mexico and Central America.
• Cristobal is the earliest third named storm of an Atlantic hurricane season on record.
• It is too early to say when and where it might strike the United States, but the projected path would send it toward the U.S. Gulf Coast over the weekend.

Forecast U.S. Impacts

• Even if Cristobal doesn't attain hurricane status, that doesn't mean it won't have serious impacts.
• Cristobal is expected to have a rather large wind field for a tropical storm. Furthermore, early-June storms like Cristobal tend to be lopsided, with significant impacts far from the track of the center.
• In this case, with a northward-moving Cristobal in the Gulf of Mexico, this will spread significant impacts well to the east of the center. These impacts may also arrive well ahead of the center making landfall.
• This is yet another case where the forecast path will not tell the whole story of impacts.

About Atlantic Hurricane Season

• Tropical cyclones in the North Atlantic are called hurricanes, tropical storms, or tropical depressions.
• The Atlantic hurricane season is the period in a year when hurricanes usually form in the Atlantic Ocean.
• In the Northern Atlantic Ocean, a distinct hurricane season occurs from June 1 to November 30, sharply peeking from late August through September.
• Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures is large and sea surface temperatures is the greatest.

Favourable Conditions in Gulf Of Mexico

• Sea surface temperature is generally very high in southwestern Gulf of Mexico, which is to allow the system to strengthen.
• Wind shear i.e. the increase in wind speed with height in the atmosphere, or a sharp change in wind direction, is low as the storm emerges over open water and begins its northward
• The low wind shear favors strengthening of the system even if interaction with Mexico first weakens the storm.

About Gulf of Mexico

• It is partially landlocked body of water on the southeastern periphery of the North American continent. 
• It is connected to the Atlantic Ocean by the Straits of Florida, running between the peninsula of Florida and the island of Cuba, and to the Caribbean Sea by the Yucatán Channel, which runs between the Yucatán Peninsula and Cuba. 
• Both of these channels are about 100 miles (160 km) wide. The gulf’s greatest east-west and north-south extents are approximately 1,100 and 800 miles (1,800 and 1,300 km), respectively, and it covers an area of some 600,000 square miles (1,550,000 square km). 
• To the northwest, north, and northeast it is bounded by the southern coast of the United States, while to the west, south, and southeast it is bounded by the east coast of Mexico.