Tropical Storm Philippe Map as Path Set To Change

Tropical Storm Philippe is due to suddenly veer towards the north after it sideswipes the northeastern Caribbean, having been moving westward for several days.

The storm's path is projected by the National Hurricane Center to approach the Leeward Islands, including Antigua and Barbuda, on Monday night, before moving northwards throughout the rest of the week.

"Philippe is moving toward the west-northwest near 7 mph, and a northwestward motion is expected to resume later today through early Tuesday," a National Hurricane Center (NHC) public advisory stated on Monday morning. "A turn toward the north-northwest is forecast to occur by late Tuesday, followed by a northward motion on Wednesday. On the forecast track, the center of Philippe is expected to pass near or just northeast of the northern Leeward Islands later today and tonight."

The reason for the storm's sudden change in direction is due to the direction of winds that the storm is moving into.

"The movement of tropical storms and hurricanes is strongly influenced by the larger-scale weather patterns they encounter," Mathew Barlow, a professor of environmental earth and atmospheric sciences at the University of Massachusetts-Lowell, told Newsweek. "These larger-scale wind fields push or 'steer' the storm in the same direction as the winds. Tropical Storm Phillippe is going to be influenced by the southwestern side of a high-pressure system, which will steer it to the north."

"This high-pressure system is strongest in the middle of the troposphere, around the 500 hPa pressure level (about 3.4 miles above the surface), so it is referred to as a 'mid-level' high or ridge," Barlow said.

As of 8 a.m. AST, the storm was about 95 miles east-southeast of Barbuda.

The paths of storms and hurricanes are predicted using a variety of observations and weather prediction models.

"Observations for storms far from land, such as Tropical Storm Phillippe, are frequently derived from satellites and aircraft measurements from the NOAA and Air Force Hurricane Hunters," Nicholas S. Grondin, an assistant professor of meteorology and physical geography at the University of Tampa, previously told Newsweek. "Closer to land, ground-based observations from surface stations and radar are useful tools for forecasters to use. Numerical weather prediction or computer models are used during all stages of forecasting storm tracks and intensity."

"One common tool is to use ensemble forecasts, which are multiple runs of the same computer model with slightly different initial conditions," Grondin said. "In general, National Hurricane Center forecasts are very good and continue to improve with time, especially track forecasts. For example, the National Hurricane Center 72-hour track forecast error has improved from over 200 nautical miles in 2000 to about 75 nautical miles in 2022."

A Tropical Storm Watch is in effect for both Antigua and Barbuda, with 4 to 6 inches of rain being forecast through Tuesday, which may lead to scattered flash flooding. The other Leeward Islands are to expect 2 to 4 inches, according to the NHC.

Philippe may even strengthen into a hurricane in the coming days.

"Maximum sustained winds remain near 50 mph with higher gusts. Little change in strength is forecast during the next day or so, but Philippe could begin to intensify more significantly around the middle of the week," an advisory said.

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