Tropical Storm Rafael to become hurricane, threaten US by weekend
Tropical Storm Rafael in the Caribbean will strengthen to a hurricane in the coming days, and will eventually emerge over the Gulf of Mexico before delivering heavy rain to part of the United States.
As of 10 a.m. EST on Tuesday, Rafael had maximum sustained winds of60 mph, was moving toward the northwest at 13 mph and was located 65 miles to the southwest of Montego Bay, Jamaica.
"Steering breezes will guide the tropical storm on a northwesterly track that takes it near Jamaica and the Cayman Islands on Tuesday and then across Cuba at midweek," AccuWeather Chief On-Air Meteorologist Bernie Rayno said, "In this zone, waters are sufficiently warm, and disruptive breezes and wind shear will be low."
As the storm moves northward through the middle of the week and gains wind intensity, heavy, flooding rain and damaging winds are expected across Jamaica and Cuba. There will be the likelihood of flash flooding and mudslides.
"This storm is expected to make landfall Wednesday morning as a Category 1 or possibly a Category 2 hurricane on the Saffir-Simpson Hurricane Wind Scale in western Cuba," AccuWeather Meteorologist Geordan Lewis said. A storm surge of 6-10 feet can occur in parts of the south-facing coastline.
The AccuWeather RealImpact™ Scale for Hurricanes is a 1 for Jamaica and a 2 for Cuba. The RealImpact™ Scale considers the magnitude of rainfall, storm surge, mudslides, flooding and wind, as well as the economic impacts on populated areas.
The Saffir-Simpson Scale only takes into account the storm's wind intensity.
The tropical threat will spend some time as a Category 1 or 2 hurricane before losing some wind intensity while approaching the U.S. central Gulf Coast this weekend due to progressively cooler waters and increasing wind shear. The RealImpact™ for the U.S. is a 1.
The storm will be large enough and strong enough to create rough seas over the Gulf of Mexico, building surf and triggering beach erosion along shores. Some coastal flooding is likely to the north and east of the storm track, where winds will push Gulf waters shoreward.
The highest probability of landfall is along the central Louisiana coast. However, since steering breezes may change a bit late this week and this weekend due to the approach of a non-tropical storm from the south-central U.S., there is a wide window as to where landfall will occur. That landfall potential zone extends from the Florida Panhandle to the Texas coast.
Other scenarios take a much weaker tropical feature much farther to the west toward Mexico versus the U.S. In this case, impacts on the U.S. could be minimal, and Rafael could succumb to wind shear.
A stronger hurricane may also tend to track more to the east rather than north. In this case, impacts would be greater along the Florida Gulf coast, including from storm surge.
In yet another scenario, the feature may lose so much wind intensity that it arrives in the U.S. as a tropical depression or wind and rainstorm. Regardless, this will not be a situation where there is a strengthening major hurricane that makes landfall in the U.S., but rather something less intense in terms of wind intensity. Impacts from rainfall can still be experienced well inland.
Dangerous and damaging effects will extend outward from the storm center, especially on its eastern side. People should not just focus on the eye path but rather on AccuWeather's forecast impact zones, which its team of dozens of meteorologists will heavily scrutinize throughout the storm's life cycle.
Differences and similarities to Helene regarding rainfall, flooding
Together with the non-tropical storm, Rafael will spread a zone of drenching rain and locally severe thunderstorms over parts of the interior South Central and Southeastern states as it moves inland.
Heavy rainfall is forecast to precede any direct rain from Rafael and may prime the dry landscape enough to trigger flooding more easily than if the new tropical storm were to move over the region by itself.
A similar, yet more extreme condition was present during Helene. In the case of pre-Rafael impacts, the heaviest rain is likely to fall on coastal areas of Georgia and South Carolina rather than the southern Appalachians. Heavy rain fell on the southern Appalachians rather than the coast pre-Helene.
In the case of the recent flash flood disaster in the southern Appalachians, intense rain fell in a matter of hours just before Helene's arrival. In the current situation, the widespread dry ground may be able to absorb a significant amount of rain that falls at midweek, where that rain is spread out over a couple of days rather than a few hours. There is also a longer gap in between both rain events, this time when compared to Helene.
Regardless, enough rain could fall on the southern Appalachians and parts of the Southeast states to cause flooding and other issues. Even though the ground has become dry in recent weeks post-Helene, it may not take as much rain to trigger issues in the region, especially where drainage infrastructure and roads have not been fully repaired since Hurricane Helene. A damaged tree canopy post-Helene may also lead to greater and faster runoff in some instances.
Any tropical storm or hurricane that transitions to a tropical rainstorm has the potential for excessive rainfall and flooding.
While the magnitude of flooding that occurred over the southern Appalachians from Helene is unlikely to occur in the same area with Rafael, any location where rain concentrates and falls at a heavy rate for multiple hours could be at risk for significant urban flooding and flooding along small streams.
Aside from the risk of flash flooding, which may be focused on a small area, the storm may bring much-needed rain and wildfire relief over a broad zone later this weekend to next week. In some cases, the storm duo may bring the first soaking rain in months to parts of the Central and Eastern states.
No matter how similar the setup from Rafael may seem to Helene, no two storms and setups are ever the same.
Elsewhere in the tropical Atlantic
AccuWeather meteorologists are watching another area that could churn out a tropical depression or storm as it approaches the Leeward Islands and moves along the northern islands of the Caribbean this week.
Sara is the next name on the list of tropical storms for the 2024 Atlantic Hurricane season after Rafael.
.png)
No comments:
Post a Comment