Wet Start to Week, Very Active in the Tropics
OUR WEATHER SETUP: A ridge has been in place the past few days allowing for hot and humid conditions with only isolated storms. Temperatures have been in the lower 90s, which is a few degrees above average for this time of year. For today, and the next several days, the ridge will weaken over Alabama and allow a frontal boundary to stall across the state meaning an increase in our rain chances.
THE WEEK AHEAD: Look for rather unsettled weather for the first half of the week, with scattered to numerous showers and thunderstorms Monday through Wednesday as the surface front stalls out near the Tennessee border. Highs will be in the low to mid 80s with only a limited amount of sun. Showers should thin out Thursday and Friday.
VERY ACTIVE IN THE TROPICS: Which is should be as this week is the statistical peak of the season…Five areas of concern…
FLORENCE: At 500 AM AST (0900 UTC), the center of Hurricane Florence was located near latitude 24.9 North, longitude 58.9 West. Florence is moving toward the west-northwest near 9 mph (15 km/h). A west-northwestward motion with an increase in forward speed is expected during the next couple of days. A turn toward the northwest is forecast to occur Wednesday night or Thursday. On the forecast track, the center of Florence will move over the southwestern Atlantic Ocean between Bermuda and the Bahamas Tuesday and Wednesday, and approach the southeastern coast of the United States on Thursday. Satellite imagery indicates that the maximum sustained winds have increased to near 105 mph (165 km/h) with higher gusts. Rapid strengthening is forecast, and Florence is forecast to become a major hurricane this morning, and is expected to remain an extremely dangerous major hurricane through Thursday. Hurricane-force winds extend outward up to 25 miles (35 km) from the center and tropical-storm-force winds extend outward up to 125 miles (205 km). The estimated minimum central pressure is 969 mb (28.62 inches).
There is an increasing risk of life-threatening impacts from Florence: storm surge at the coast, freshwater flooding from a prolonged and exceptionally heavy rainfall event inland, and damaging hurricane-force winds. While it is too soon to determine the exact timing, location, and magnitude of these impacts, interests at the coast and inland from South Carolina into the mid-Atlantic region should closely monitor the progress of Florence, ensure they have their hurricane plan in place, and follow any advice given by local officials.
HELENE: At 500 AM AST (0900 UTC), the center of Hurricane Helene was located near latitude 14.3 North, longitude 28.9 West. Helene is moving toward the west-northwest near 17 mph (28 km/h) and this motion is expected to continue for another couple of days. A turn to the northwest is forecast to occur on Wednesday. Maximum sustained winds are near 85 mph (140 km/h) with higher gusts. Helene’s expected to resume strengthening today. Afterward, weakening is forecast to commence Wednesday morning. Hurricane-force winds extend outward up to 25 miles (35 km) from the center and tropical-storm-force winds extend outward up to 90 miles (150 km). The estimated minimum central pressure is 984 mb (29.06 inches).
ISAAC: At 500 AM AST (0900 UTC), the center of Hurricane Isaac was located near latitude 14.7 North, longitude 42.7 West. Isaac is moving toward the west near 13 mph (20 km/h). A westward motion with a slight increase in forward speed is forecast through the end of the week. On the forecast track, Isaac is forecast to move across the Lesser Antilles and into the eastern Caribbean Sea on Thursday. Maximum sustained winds remain near 75 mph (120 km/h) with higher gusts. Additional strengthening is expected over the next day or two. Weakening is forecast to begin by the middle of the week as Isaac approaches the Lesser Antilles. Isaac is a small hurricane. Hurricane-force winds extend outward up to 10 miles (20 km) from the center and tropical-storm-force winds extend outward up to 45 miles (75 km). The estimated minimum central pressure is 993 mb (29.33 inches).
ELSEWHERE: Disorganized showers and thunderstorms over the northwestern Caribbean Sea are associated with a tropical wave and an upper-level trough. The disturbance is forecast to move slowly west-northwestward to northwestward across the northwestern Caribbean Sea and the Yucatan peninsula during the next couple of days with little or no development expected during that time. However, upper-level winds are forecast to become a little more conducive for development when the system moves across the western Gulf of Mexico Wednesday through Friday. Formation chance through 5 days…low…30 percent.
A non-tropical area of low pressure is forecast to form in the northeastern Atlantic Ocean several hundred miles west-southwest of the Azores in two or three days. Some slow tropical or subtropical development is possible by the end of the week while the low moves southwestward. Formation chance through 5 days…medium…40 percent.
Next names up for use Joyce and Kirk.
WEEKEND SNEAK PEEK: Ridge builds back in it looks like with more sun than clouds, only isolated afternoon storms, and highs in the 90s, which is once again above average for this time of year.
Have a great day!
Ryan
