Tuesday may be one of the busier weather days we’ve had so far in 2019 as low pressure is expected to brush the coast with strong, gusty winds and a bout of heavy (yet much-needed) rainfall. This may have impacts on the morning commute.

Heavy rainfall, flooding potential for the morning rush

The key concern for Tuesday morning will be the potential for heavy rainfall coinciding with the 7:03am high tide. As low pressure spins up off the coast and interacts with a potent dose of mid-level energy, substantial rain is expected to break out — we could see an inch or more of rain fall in a short period of time. While the ground is very dry, urban flooding can still become a factor quickly with any heavy rain at high tide.

Stiff onshore winds will be another factor. Winds will blow 20-30 MPH from the northeast during the morning, with gusts 40-45 MPH possible as the low passes just offshore. This will make for treacherous bridge driving, especially for high-profile vehicles. A Wind Advisory will be in effect from 5am-1pm Tuesday as a result.

These winds may also have the effect of driving tides up near coastal flooding thresholds. Probabilistic surge guidance is in good agreement that tides will approach 6.7-6.9′ in the harbor tomorrow morning; coastal flooding tends to start around 7′. Even if the water level falls short of 7′, these tide levels will have significant impediments on drainage. Be ready for the potential for heavy traffic and road closures.

Chilly temperatures to continue

Breezy northeast winds and will continue to bring cold air into the area for Tuesday; cloud cover and rainfall will reinforce this chilly airmass. Don’t expect temperatures to get out of the 50s. The one possible exception could come if the low trends a bit onshore. This could bring a warm front along for the ride, briefly sending temperatures into the 60s along the coast for a period of time. Don’t count on this, though.

Improvement by evening

As the low pressure system departs quickly to the northeast, conditions will steadily improve, with even some clearing developing around and after sunset. Winds will go around to the north and then northwest, tapering off as the low departs.

Bottom line

• Heavy rainfall may have impacts on the morning commute Tuesday. Flooding and road closures are possible in downtown Charleston. Turn around, don’t drown!
• Winds will be quite strong in the morning, making driving on bridges potentially hazardous, especially for high-profile vehicles. This will improve during the afternoon.
• Temperatures will remain much cooler than normal for early April.
• Wednesday looks a lot better — much more sun with highs approaching 70.

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