Hurricane Joaquin #2

10/01/2015, 3:00 p.m.

Coastal Flooding due to Hurricane Joaquin

...Heavy Rainfall/flooding and Possibly Some Coastal Flooding Biggest Concern...

Major Hurricane Joaquin (CAT 3) continues to move very slowly toward the southwest at 6 mph around the Bahama Island region.  The hurricane is not expected to turn more toward the north until very late tonight and Friday.  Once it turns toward the north, then we will likely have a better idea on the track of the hurricane into this weekend.

Right now, please closely monitor the latest forecasts from the National Hurricane Center, since there is still much uncertainty with the exact track.

Although we are not expecting the hurricane to directly strike our region at this time, we are very concerned about the potential for heavy rainfall and flooding, as well as the possibility for some coastal flooding.


Possible Impacts and Timing:

What: Heavy Rainfall/Flooding

We have a moderate to high confidence that at least 4 to 6 inches of rainfall will occur between now and Saturday night, with much higher amounts possible.

  • Where:  Highest probability for heavy rainfall/flooding will be over our South Carolina counties, but there is still considerable uncertainty to the exact amount and location. 
  • When:  Mainly Friday through Saturday Night, but could occur a little earlier.
  • Impacts: It is very difficult to forecast exact impacts from heavy rainfall, given the rainfall amounts and exact locations are difficult to determine.  Regions that get more than 4 to 6 inches over the few days will have a higher likelihood for fresh water flooding, especially urban areas that have drainage that is affected by the tide levels, such as Charleston. Be on the lookout for flooded roads and potential road closures.

What:  Elevated Tides/Coastal Flooding

  • Where:  Elevated tides are expected along our entire coast, but the highest levels may be over our South Carolina coast, since the latest models show stronger easterly/onshore winds across that region. Tide levels may likely approach or exceed our Coastal Flood Warning levels.
  • When: Tides will be elevated now through early Sunday, with the highest tide levels expected with the major high tide cycles Friday and Saturday. Other possible coastal impacts would include: beach erosion, rip currents, and high surf.