Cape Hatteras to Ocracoke Inlet, NC out 20 NM Marine Forecast
|Rest Of Today...S Winds 20 To 25 Kt, Becoming Sw 15 To 20 Kt Late. Seas Around 9 Ft. Dominant Period 7 Seconds. A Slight Chance Of Tstms. Showers.|
|Tonight...Sw Winds 20 To 25 Kt, Diminishing To 15 To 20 Kt After Midnight. Seas 6 To 9 Ft, Subsiding To 5 To 6 Ft After Midnight. Dominant Period 7 Seconds. Showers Likely With A Slight Chance Of Tstms.|
|Thu...Sw Winds 10 To 15 Kt, Diminishing To 5 To 10 Kt In The Afternoon. Seas 4 To 6 Ft. Dominant Period 7 Seconds. Showers Likely. A Chance Of Tstms In The Morning, Then Tstms Likely In The Afternoon.|
|Thu Night...N Winds 5 To 10 Kt. Seas 4 To 5 Ft. Dominant Period 7 Seconds. Showers And Tstms Likely In The Evening, Then A Chance Of Showers After Midnight.|
|Fri...Ne Winds 5 To 10 Kt, Becoming Se In The Afternoon. Seas 3 To 4 Ft. A Chance Of Showers And Tstms.|
|Fri Night...S Winds 10 To 15 Kt. Seas Around 3 Ft. A Chance Of Tstms. A Chance Of Showers In The Evening, Then Showers Likely After Midnight.|
|Sat...Sw Winds 10 To 15 Kt. Seas Around 3 Ft. A Chance Of Tstms. Showers Likely, Then A Chance Of Showers.|
|Sun...Sw Winds 5 To 10 Kt. Seas Around 3 Ft. A Chance Of Showers And Tstms. Winds And Seas Higher In And Near Tstms.|
| 1032 AM EDT Wed Aug 4 2021 |
Synopsis for Eastern North Carolina coastal waters - AMZ100
A weak frontal system will remain stalled near the coast through Thursday with several waves of low pressure moving along it. Weak high pressure will build into the area for Friday with another front impacting the area Friday night into Saturday. High pressure then builds over the area for early next week.
| Area Forecast Discussion|
National Weather Service Newport/Morehead City NC
915am EDT Wednesday August 4 2021
A frontal system will remain near the coast through Thursday with several waves of low pressure moving along it. Weak high pressure will build into the area for Friday with another front impacting the area Friday night into Saturday. High pressure then builds over the area for early next week.
Near Term - Today
As of 9am Wednesday...Biggest update this morning was to capture higher Quantitative Precipitation Forecast amounts along and east of the stalled boundary, presently stretched from roughly Pine Knoll Shores to Nags Head. Weak surface low pressure is located across Onslow Bay, slowly lifting northeast towards the OBX. Morning rainfall observations from CoCoRaHS and COOP observers range 4 to 8 inches across Eastern NC, with additional 1-3 inches expected.
The Flash Flood Watch continues for counties along and east of HWY 17 this morning, and will continue for these areas into Thursday morning. Low pressure will lift north of the area later this afternoon, but clouds and precipitation will hold high temps in the mid 70s across Eastern NC. Categorical PoPs along and east of HWY 17 this morning will diminish to likely PoPs by the afternoon, with a slight chance of rain for inland Coastal Plain counties.
Short Term - 6pm This Evening Through 6am Thursday
As of 405am Wednesday...Precipitation coverage should be almost nil well inland, but will continue high chance Probability of Precipitation along the coast as 3km NAM and other models and a slight upsurge in PWATs in the early nighttime hours. Amounts will be under one-half inch, so the threat of additional flooding will be reduced. Under cloudy skies with rain-cooler air, lows will range from the mid 60s well inland to low/mid 70s immediate coast.
Long Term - Thursday Through Tuesday
As of 250am Wed...The threat of widespread, heavy rains and flash flooding should end by Thu morning as the mid level trough fills and lifts and the surface boundary drifts offshore pushing the deep moisture off of the coast by afternoon. Upper level ridging briefly builds over the region Fri into Sat resulting in scattered coverage of and more diurnally driven convective activity Thu afternoon and Fri. A shortwave trough will move through Sat and Sat night leading to an uptick in showers and storms late Fri night and Sat. More substantial upper ridging is forecast to build over the region early next week leading to warm temps and isolated to scattered mainly afternoon and evening showers and storms beginning Sunday.
Thursday...Improving conditions are expected Thu from late morning on as the widespread and heaviest precipitation gets shunted offshore. Will see some isolated to scattered diurnal showers and storms in the afternoon but coverage should be low.
Friday...Expecting more typical scattered afternoon/evening showers and thunderstorms with heating. Greatest coverage expected south of Highway 70 as moisture begins to stream north ahead of advancing mid level shortwave trough.
Saturday...scattered to numerous showers and tstms expected as the aforementioned shortwave moves into the area. This activity is likely to develop souther areas Fri night then continue area wide into Sat evening.
Sunday through Early Next Week
More typical summer weather expected through the period with isolated to scattered mainly afternoon/evening showers and thunderstorms and warm temperatures.
SHORT TERM /Today and Tonight/... As of 905am Wednesday...Latest surface and buoy data indicate the weak boundary oriented from roughly Beaufort Inlet north- northeast to Oregon Inlet this morning, with southerly winds on the east side of the front and NNW winds on the west side. Winds continue to gust above SCA (Small Craft Advisory) levels for the coastal waters and Pamlico Sound, with seas ranging 5-8 feet. A weak surface low over Onslow bay will lift northeast towards the central OBX today and offshore by the afternoon. As the low strengthens, winds should range 15-25 knots today with some higher gusts. Seas are expected to peak at 6-9 feet, before dropping off to 4-6 feet tonight as SW winds drop to 15 knots or less toward morning on Thursday.
Long Term - Thursday Through Sunday
As of 250am Wed...The front is forecast to move offshore Thu with the flow becoming N/NE 10-15 kt behind it. Winds veer around to SE/S 10-15 kt Fri afternoon, then S/SW 5-15 kt Sat and Sunday. 4-6 ft seas over the outer central waters early Thu morning will subside to 3-5 ft Thu afternoon and 2-4 ft Thu night and Fri. Seas are forecast to be 2-3 ft Sat and Sunday.
As of 330am Wed...Given current radar trends, have dropped the far western portion of the Flash Flood Watch. Model guidance and Quantitative Precipitation Forecast from WPC continue to show 6" to 10" of rain possible along the coast and this will remain our highest area of concern for flash flooding. Farther inland Quantitative Precipitation Forecast amounts drop off slightly, with 3" to 6" expected. However, flash flooding is still possible over all of Eastern NC given the very efficient rain processes and the very slow storm motion. Isolated higher amounts are possible given such a primed atmosphere. We will see a substantial break Wednesday afternoon and Wednesday evening. A new round of potentially heavy rains will approach coastal areas Wednesday night into early Thu with the flood threat then ending by Thu afternoon as the deeper moisture gets pushed offshore. Future adjustments to the watch may be needed after we get through our heavy rain tonight into Wednesday.
NOAA Newport/Morehead City NC Office - Watches - Warnings - Advisories
NC...Beach Hazards Statement until 8pm EDT this evening for NCZ195- 196-199-203>205. Flash Flood Watch through Thursday morning for NCZ045>047-080- 081-092-094-193>196-198-199-203>205.
Small Craft Advisory until 11pm EDT this evening for AMZ135(Pamlico Sound). Small Craft Advisory until 6pm EDT this evening for AMZ231. Small Craft Advisory until 6am EDT Thursday for AMZ150-152- 158. Small Craft Advisory until 11am EDT Thursday for AMZ154. Small Craft Advisory until 10am EDT Thursday for AMZ156.