Tropical Storm Bertha

Tropical Storm Bertha Track 1700 Hours May 27 2020
Tropical Storm Bertha Track 1700 Hours May 27 2020

Tropical Depression Bertha RainfallTropical Depression Bertha NWS National Hurricane Center Miami FL 500 PM EDT Wed May 27, 2020 (see video below)

Surface observations and WSR-88D radar data indicate that the center of Bertha continues to move farther inland across central and northern South Carolina. Based on surface observations, the maximum sustained winds have decreased to near 25 kt, with these winds mainly along the coastal areas to the east of the center. Additional weakening is expected as the system moves farther inland, with Bertha forecast to decay to a remnant low-pressure area on Thursday, followed by dissipation on Thursday night.

The initial motion is 340/13. The cyclone is located between the subtropical ridge to the east and a large deep-layer low pressure area over the lower Mississippi River valley. These features should steer the system and its associated rainfall generally northward during the next day or so, followed by a turn toward the north-northeast before dissipation between 24-36 h. The new forecast track is nudged a little to the west of the previous track-based mainly on the initial location and motion.

This is the last advisory on Bertha issued by the National Hurricane Center.

Key Messages:

1. Bertha may produce life-threatening flash flooding across portions of northeastern South Carolina into west central to far southeast North Carolina and Southwest Virginia. Ongoing river flooding will be aggravated and recessions prolonged in the region.

FORECAST POSITIONS AND MAX WINDS

INIT  27/2100Z 34.4N  80.3W   25 KT  30 MPH - (WSW McBee, SC)
 12H  28/0600Z 37.0N  80.7W   25 KT  30 MPH - (ENE Hiwassee, VA)
 24H  28/1800Z 41.7N  79.7W   20 KT  25 MPH - (ENE Hydetown, PA)

Tropical Storm Bertha National Hurricane Center Miami FL 1100 AM EDT Wed May 27, 2020

The circulation of Bertha remained compact yet well-defined through landfall, which occurred around 930 AM EDT near Mount Pleasant, South Carolina. Buoy data around that time indicated that maximum sustained winds had increased to around 45 kt. Although the center has moved inland, a strong rain band with onshore flow continues to slowly migrate northward along the South Carolina coast. Therefore it is anticipated that tropical-storm-force winds will remain possible in the warning area over the next few hours. Bertha is expected to weaken to a tropical depression later today, then weaken to a remnant low tonight as the center moves farther inland.

Model guidance is in good agreement on taking the weakening cyclone north to north-northwestward through tonight, followed by a turn to the north-northeast along with an increase in forward speed later on Thursday. This official track is only slightly east of the previous one and is near the multi-model consensus.

Key Messages:

1. Bertha may produce life-threatening flash flooding across portions of eastern to central South Carolina into west central to far southeast North Carolina and Southwest Virginia. Ongoing river flooding will be aggravated and recessions prolonged in the region.

2. Bertha is expected to continue to bring tropical storm winds to portions of the South Carolina coast within the warning area over next few hours.

ORECAST POSITIONS AND MAX WINDS

INIT  27/1500Z 33.3N  79.5W   45 KT  50 MPH - Tropical Storm -(WSW Georgetown, SC)
 12H  28/0000Z 35.2N  80.0W   30 KT  35 MPH...INLAND
 24H  28/1200Z 38.8N  79.9W   20 KT  25 MPH...INLAND
 36H  29/0000Z...DISSIPATED

Video: Tropical Storm Bertha makes landfall along coast of South Carolina