FXUS62 KCHS 261910 AFDCHS
Area Forecast Discussion National Weather Service Charleston SC 310 PM EDT Sun Apr 26 2026
.WHAT HAS CHANGED...
All sections were updated.
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.KEY MESSAGES...
- 1) A cold front moving through our area this evening will
bring increased rain chances.
- 2) Breezy and dry conditions on Monday.
- 3) Minor coastal flooding is possible along the southeast
South Carolina coast with the Monday evening high tide.
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.DISCUSSION...
KEY MESSAGE 1: A cold front moving through our area this evening will bring increased rain chances.
The mid-levels consist of a shortwave passing just to our north this evening and overnight. At the surface, a cold front is currently moving over our area and will continue to shift towards the coast into this evening, then quickly shift offshore tonight. Meanwhile, High pressure will build in from the north. Radar imagery indicates isolated to scattered showers associated with the cold front over our area. There are hints of a weak sea breeze, but convection along it has not been too intense. Overall, coverage and intensity has been less than what the hi-res CAMS and the synoptic models have been showing. Therefore, we trended the POPs and QPF lower. Expect scattered showers for the next few hours, dissipating from north to south this evening as drier air moves in from the north. There's not much instability, so the risk of thunderstorms is low. The risk of excessive rainfall is also very low, which is good because then there won't be any flooding concerns. But it's bad because the drought will persist.
KEY MESSAGE 2: Breezy and dry conditions on Monday.
High pressure will build into our region on Monday, bringing drier conditions. Dew points should drop into the mid to upper 40s inland during the afternoon, except higher at/near the beaches. High temperatures should also be a few degrees below normal, mainly in the mid to upper 70s, except cooler at the beaches. This will result in minimum RH values generally in the 30-40% range inland. Additionally, northeast winds will be breezy in the morning with gusts around 20-25 mph, easing through the afternoon. Even though the current forecast is much lower than the model guidance, it's still short of critical thresholds for a Fire Danger Statement. Fuels remain unusually dry and the drought persists, which could still support enhanced fire behavior.
KEY MESSAGE 3: Minor coastal flooding is possible along the southeast South Carolina coast with the Monday evening high tide.
The combination of rising astronomical tides associated with the upcoming full moon along with strong and gusty northeast winds will cause tidal anomalies to increase on Monday. The Charleston tide gauge could hit 7 ft MLLW with the Monday evening high tide, so a Coastal Flood Advisory may be needed.
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.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
18Z TAFs: Radar imagery indicates isolated to scattered showers associated with a cold front over our area and all of these features are moving towards the coast. There are hints of a weak sea breeze, but convection along it has not been too intense. Given the radar imagery and the latest hi-res CAMs, we maintained the TEMPO thunderstorm groups at all three TAF sites for the upcoming hours. Though, there are concerns these time periods may be too long. Amendments may be needed based on future radar trends. Regardless, any convection is expected to dissipate this evening as drier air moves in from the north. Then, ceilings will lower to MVFR at all three TAF sites and persist through the night and into Monday morning. We can't rule out IFR, but didn't have enough confidence to add this to the TAFs. Ceilings should improve towards Monday late morning and early afternoon.
Extended Aviation Outlook: A front could bring flight restrictions on Wednesday.
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.MARINE...
A cold front will move through the waters this evening, then quickly shift offshore tonight. Meanwhile, High pressure will build in from the north. The interaction between these two features will cause the pressure gradient to become elevated, leading to increasing northeasterly winds and building short period seas. We maintained the Small Craft Advisories from tonight into Monday. Winds gusts in the Charleston Harbor should stay under 25 kt, so we're not expecting an Advisory. As the High builds further into our area later Monday into Tuesday, the pressure gradient will lessen, causing winds and seas to trend lower. Likewise, Small Craft Advisories will gradually drop off Monday evening/night. Another cold front could move through the area on Wednesday, bringing a brief surge in winds and seas, and maybe Small Craft Advisories for some of our waters Wednesday night.
Rip Currents: Monday: The combination of strong, gusty northeast winds and elevated seas will lead to a Moderate Risk of rip currents at all of our beaches.
Tuesday: The Moderate Risk of rip currents should persist at our GA beaches.
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.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None. SC...None. MARINE...Small Craft Advisory from 9 PM this evening to 8 PM EDT Monday
for AMZ360. Small Craft Advisory from 11 PM this evening to 5 PM EDT Monday for AMZ362. Small Craft Advisory from 2 AM to 5 PM EDT Monday for AMZ364. Small Craft Advisory from 2 AM Monday to 5 AM EDT Tuesday for AMZ384.
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