Cape Fear to Little River Inlet, SC out 20 NM Marine Forecast
|Rest Of Today...W Winds 5 To 10 Kt. Seas 3 To 4 Ft.|
|Tonight...Sw Winds 5 To 10 Kt. Seas 2 To 3 Ft.|
|Thu...W Winds 5 Kt, Becoming S In The Afternoon. Seas 2 Ft.|
|Thu Night...S Winds 5 To 10 Kt. Seas 2 To 3 Ft. A Slight Chance Of Showers.|
|Fri...Se Winds 5 To 10 Kt. Seas 2 To 3 Ft. A Chance Of Showers With A Slight Chance Of Tstms.|
|Fri Night...Se Winds 5 To 10 Kt, Becoming S 10 To 15 Kt After Midnight. Seas 2 To 3 Ft. A Chance Of Showers.|
|Sat...Se Winds 10 To 15 Kt, Becoming S 5 To 10 Kt After Midnight. Seas 3 To 4 Ft. A Chance Of Showers.|
|Sun...S Winds 5 To 10 Kt, Becoming Sw 10 To 15 Kt After Midnight. Seas 2 To 3 Ft. A Chance Of Showers. Winds And Seas Higher In And Near Tstms.|
| Area Forecast Discussion|
National Weather Service Wilmington NC
1009am EDT Wednesday September 23 2020
Temperatures will warm and humidity will increase as high pressure settles offshore through mid to late week. Moisture from the remnants of Beta will increase rain chances late Thursday into the weekend. Ocean conditions will continue to gradually improve, especially as we head into the weekend, as Teddy's swell continues to subside.
Forecast on track. Mid to high clouds will stream across the area today, thick enough at times to filter out the sun, but should see enough sun to keep temps on track, reaching well into the 70s today. Minor coastal flooding should occur along area beaches, from Cape Fear northward and along the Cape Fear River downtown. Rip current threat continues with long period swells from Teddy still reaching into our area waters.
Near Term - Through Thursday
Surface high pressure centered across the southern Appalachians will weaken today and redevelop offshore this evening. Mainly thin cirrus streaming well out ahead of former Tropical Storm Beta will cover the sky but should have only a limited impact on temperatures. With the airmass continuing to slowly modify, expect highs to reach 73-78 today, coolest along the beaches where a weak seabreeze should develop.
Calm winds and a little thicker cirrus cloud cover are expected tonight with lows 55-60. By Thursday the remnant low from Beta will begin to kick out to the northeast across Louisiana and Mississippi. With the high moving out toward Bermuda, increasing southerly flow between these two systems should begin to push dewpoints back toward 60 as a warm front develops across the area. Model forecast soundings show insufficient moisture for any significant low or mid clouds, so I'm keeping showers out of the forecast. Thursday's highs should reach the upper 70s away from the beaches.
Short Term - Thursday Night Through Friday Night
Mid-level ridging off the SE U.S. Coast and extending into the Carolinas Thu night, will flatten out as a mid-level positively tilted trough in the lower to mid Mississippi Valley picks up Beta or the remnants of, and lifts it toward the NE, reaching the Appalachians of the Western Carolinas by late Fri. Difficult to discern Beta Fri night. However, the GFS seems quick with the mid-level trough axis pushing across and off the Carolina Coasts by Sat morning, taking Beta with it. With drier air in the mid and upper levels reaching the FA overnight. The surface ridge axis from the high's center offshore and east of NC, will extend inland north of the FA this period. This orientation will allow increasing moisture under SE-S winds in the lower levels to advect across the FA late Thu night thru Fri night. Will indicate increasing POPs Thu night, peaking during the day on Fri which is the time when PWs peak with much of the atm column saturated. Will back off POPs to just isolated during Fri night. Stayed close to a consensus with temps with an overall milder/warmer trend.
Long Term - Saturday Through Tuesday
Ridging in the mid-levels is expected to Probability of Precipitation back up after the mid-level trough, with what's left of Beta, exits stage right, off to the northeast during Sat. This track keeps it north of the FA. This ridging aloft will temporary hold, affecting the FA well into Sun. At the sfc, ridging from the high's center well offshore from the Carolinas, will extend initially across the FA, then drop southward Sun. The moist surface SE-S flow will veer to the SSW-SW, with some noted drying Sat into Sun. POPs generally 30-40 Sat, mainly earlier in the day,dropping to 20-30 Sat night thru Sun. Late Sunday into early next week, the main belt of westerlies are forecast to begin expanding southward as flow aloft amplifies. At the sfc, a front tries to drop southward Sunday into Mon, but hangs up just north of the FA as it becomes parallel with the flow aloft. However late Tuesday leading into Wed, is when the best amplification of the flow aloft begins to take shape. This will push a much stronger cold front to the doorsteps of the FA by Wednesday daybreak. This far out in time, won't get too hung up on it's location. But the general trend in the models is for the possibility of another round of cool weather after this CFP. Could only indicate 20-30 POPs Monday thru Tuesday night, with the hier Probability of Precipitation range situated ahead of the cold fronts. Generally used a model MOS consensus with max/min temps this period.
Today through Thursday... High pressure centered across the southern Appalachians this morning will shift offshore tonight. Light westerly winds this morning will become more southerly this afternoon with a weak seabreeze circulation. Southerly winds will continue into Thursday as the high moves farther offshore. Although there is still long-period swell coming in from former Hurricane Teddy, the increasingly northeasterly swell direction means Cape Lookout and Cape Fear are blocking more of our coastal waters from the biggest impacts. CORMP and NOAA buoys in our area this morning are all below 5 feet with the exception of the Lejeune offshore buoy (41159) which is still reporting a 7 foot wave height. The Small Craft Advisory will be discontinued this morning. Highest waves north of Cape Fear will be 4-5 feet, with only 2-4 feet south of Cape Fear today, diminishing further tonight and Thursday.
Thursday Night through Sunday... Surface ridge axis from the offshore high's center, will extend westward and onshore north of the FA from Thu night thru Sat afternoon. This will result in a SE-SSE wind thru the period at 10 kt or less Thu night, increasing to 10-15 kt or around 15 kt Fri into early Sat. This due to a slight tightening of the surface pg as what's left of Beta remains north of the waters as it pushes off to the NE. For Sat night thru Sun, the surface ridge axis drops south of the waters, allowing winds to veer toward the SSW-SW at 10-15 kt during Sun.
Seas generally will drop to their lowest in height at the start of this period due to the degradation of Teddy's swell, which will have reduced to 10 to 11 second periods. The onshore SE-SSE winds Fri thru Sat will build seas to 2 to 4 ft thruout at basically 6 to 8 second periods. There is an inverted surface trough riding westward along the periphery of the Atlantic high's circulation, that is poised to reach the well offshore waters off the FL coast Sun. This feature will produce a swath of 7-9 second period easterly swell that will reach the area waters late Sunday or just there-after.
NOAA Wilmington NC Office: Watches - Warnings - Advisories
SC...None. NC...Coastal Flood Advisory until 3pm EDT this afternoon for NCZ106-108-110. High Rip Current Risk until 8pm EDT this evening for NCZ106- 108. Coastal Flood Advisory from 2pm this afternoon to 6pm EDT this evening for NCZ107. MARINE...None.