Tropical Storm Maria Discussion Number 43 | NWS National Hurricane Center Miami FL | 5 PM EDT Tue Sep 26 2017
Tropical Storm Maria Forecast Discussion
Tropical Storm Maria Discussion Number 43
NWS National Hurricane Center Miami FL AL152017 500 PM EDT Tue Sep 26 2017
There has been little change to Maria's cloud pattern since the previous advisory. The center of the large circulation is located near the northwestern edge of the deep convection due to west-northwesterly shear and dry air intrusion. Reconnaissance aircraft have not found any SFMR winds higher than 60 kt for quite some time, so the initial intensity has been reduced to that value.
Cool waters and moderate shear should cause some additional decrease in wind speed over the next day or so, but little change in strength is forecast later in the period as Maria accelerates east-northeastward over the north Atlantic. Maria should complete extra-tropical transition in about 96 hours, and could merge with a large extra-tropical low in about 5 days.
Maria is continuing its slow northward motion around the western side of a subtropical ridge. The mid-latitude westerlies are forecast to dip southward as a large trough moves across eastern North America later this week. This should cause Maria to turn east-northeastward by Thursday, and then accelerate ahead of the trough by late in the week. The track guidance has trended slightly slower and the NHC forecast has been adjusted accordingly.
The new official forecast is near the middle of the tightly clustered guidance.
KEY MESSAGES:
Maria is forecast to continue moving northward, paralleling the U.S. east coast for the next 36 hours, and will likely bring some direct impacts to portions of the North Carolina coast through Wednesday where a tropical storm warning is in effect.
Storm surge flooding, especially along the sound side of the North Carolina Outer Banks, is expected, and a storm surge warning and watch are in effect for portions of eastern North Carolina.
Swells generated by Maria are affecting much of the east coast of the United States. These swells are also affecting Bermuda, the Turks and Caicos Islands, and the Bahamas. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office for more information.