Hurricane Isaac along with concurrent storms Hurricane Helene and tropical storms Gordon and Joyce were all relegated to obscurity by Hurricane Florence.
ORIGINAL STORY: Tropical Storm Kirk continues to move west through the Atlantic, and forecasters continue to predict it may be in the Caribbean by Thursday morning.
NHC forecasters say that an even faster westward motion across the deep tropical Atlantic Ocean is expected through Tuesday. Satellite imagery indicates that a non-tropical low pressure system is forming along a frontal boundary about 900 miles west-southwest of the Azores.
Upper-level winds are expected to increase, limiting chances for additional development while the system moves near the southeastern US coast. National Hurricane Center advisory, Kirk's sustained winds measured 35 mph and extended 70 miles north of the storm's center. The depression is expected to weaken to a remnant low tonight or Sunday and dissipate Sunday night east of the Lesser Antilles.
Some intensification is possible this weekend, but vertical wind shear may increase next week possibly limiting additional strengthening.
"A reduction in speed is likely after 48 hours once Kirk moves south of a large central Atlantic trough, but it should still be moving along at a pretty good clip". This low, called Invest 98 for now, has been fighting a lot of wind shear, so development chances only sit at 30 percent.
The NHC official forecast is still not as high in strength as the statistical-dynamical guidance and more closely follows the HCCA, Florida State Superensemble, and intensity consensus, as well as the trends in the GFS and ECMWF.
Kirk is moving "quickly westward" at 24 miles per hour, according to the NHC at 5 a.m. on Sept 24, and it has 35 miles per hour winds.