Tropical Storm Agatha is quickly gaining strength as it closes in on Mexico’s southern coast. Forecasters expect the storm to grow into a category two hurricane before making landfall early next week. On top of wind damage, the system’s prolific rainfall will lead to flash flooding and landslides. There’s a risk the storm could redevelop in the Gulf of Mexico next week.
AGATHA QUICKLY STRENGTHENS ON APPROACH TO MEXICO
Agatha spun up during the day on Saturday from a tropical disturbance that’s been lingering in the eastern Pacific Ocean for the past couple of days. The storm is gathering strength in a hurry amid warm waters and favourable winds.
Saturday’s 7:00 p.m. CDT advisory from the U.S. National Hurricane Center (NHC) found Agatha’s maximum sustained winds had reached about 100 km/h. Forecasters expect the storm to continue strengthening as it approaches Mexico’s south coast during the day on Sunday and Monday.
The latest forecast calls for Agatha to make landfall along the Oaxaca coast early Monday afternoon, though winds and rain will far precede the centre of the storm officially making landfall.
A hurricane warning is in effect for the Oaxacan coast ahead of Agatha’s anticipated landfall, including the communities of Puerto Escondido and Salina Cruz.
The storm’s robust moisture and rough terrain of southern Mexico will combine to produce prolific rainfall through midweek as the storm makes landfall and slowly pushes inland.
Widespread rainfall totals of 200-300 mm are expected along the path of the storm, with higher totals possible in some areas. Such heavy rain will lead to life-threatening flash flooding and mudslides in the affected areas.
CLOSELY WATCHING THE GULF NEXT WEEK
The system’s effects might not stop in southern Mexico.
Agatha’s remnants will slowly push inland and may reemerge over the far southern Gulf of Mexico by the middle of next week. By then, atmospheric conditions may be favourable for the system to develop into a new system in the Gulf of Mexico.
The NHC gives this region a 20 percent potential for tropical development by the middle of the week. Forecasters will closely monitor this potential development.
If a system forms in the Gulf, it would be the Atlantic basin’s first system of the 2022 hurricane season, which officially begins on June 1st.
LA NIÑA MAY SUPPRESS PACIFIC ACTIVITY AS IT BOOSTS ATLANTIC SEASON
La Niña, an abnormal cooling of sea surface temperatures in parts of the eastern Pacific Ocean, has a significant impact on hurricane activity in both the Pacific and Atlantic Oceans.
This pattern tends to suppress hurricane activity in the central and eastern Pacific Ocean as cooler waters and increased wind shear are unfavourable for tropical development. Accordingly, NOAA’s official forecast calls for decent odds of below-normal tropical cyclone activity in the central Pacific.
While the outlook doesn't cover the eastern Pacific specifically, one can expect to see a similar pattern here because of its close proximity to the region. The hurricane season for the eastern Pacific Ocean began on May 15, and runs until November 30.
On the flip side, forecasters expect warmer-than-normal ocean temperatures and relatively calm wind shear to contribute to another above-average Atlantic hurricane season for the seventh year in a row.
Thumbnail courtesy of NOAA.