Key MESSAGE 1), High pressure will continue to push offshore bringing steady SW flow and WAA to ENC through the end of the work week. Highs inland are forecast climb into the 70s each day with the warmest day expected on Friday when thicknesses support highs in the upper 70s to near 80. Record highs for Friday are in the lower 80s inland from the coast and the record values for established climate sites can be found in the CLIMATE section below. Across the immediate coast and OBX, below normal water temperatures will keep these areas cooler with highs in the 50s to 60s each day. The one caveat that may result in slightly lower temps than currently forecast will be the extent of clouds and scattered showers as a few weak systems traverse the area late in the week.
Key Message 2), Wave guidance remains well underdone with the swell being produced by a strong low pressure system currently off the Grand Banks. Long period swell continues around 6 to 7 feet with periods of 12 to 13 seconds early this morning and have not seen much of a decrease since yesterday afternoon. The high energy swells are bringing breaking waves up to 8 ft in the surf zone with extended wave run up along the beaches. There remains a low potential for some localized ocean overwash at vulnerable locations with no dunes around high tide, which is around 7:45 this morning. Do expect the long period swells to gradually decrease as the low continues to push eastward across the central Atlantic but given the poor performance of the models, decided to extend the high surf advisory into mid afternoon.
Key Message 3), Positively tilted shortwave will track across the Pacific Northwest and into the Plains late this week with the trough taking on a more negative tilt and deepening slightly as it reaches the east coast late this weekend. At the mid levels southern stream shortwave quickly traverses the CONUS reaching the Southeast by Sun/Mon while a northern stream shortwave dives S'wards at the same time potentially phasing with the southern stream as it pushes off the Mid-Atlantic coast. At the surface, cold front will drop SE'wards across ENC on Sat and stall around the area with a wave of low pressure then riding along this stalled front and deepening after it pushes offshore bringing chances for rain to the region this weekend. Rain then gradually ends from west to east Sun night into Monday as temps fall. There is a chance for a non impactful rain/snow mix towards the end of the event this weekend Sun night into Mon. However, this will likely be the typical cold air chasing the moisture setup so have little confidence in any other ptype besides rain. Will note, while I have used a primarily NBM blend for the weekends PoPs as well, the NBM typically tends to struggle with holding onto moisture for far too long so precip could end much sooner than currently forecast. Biggest challenges with this setup is how deep the incoming trough will be as it moves over the area and will the northern and southern stream shortwaves phase as this will impact the strength of the cold air coming into ENC Sun into Mon as well as how strong the aforementioned surface low could get as it tracks across the region Sun night into Mon.
18z Wednesday through Monday VFR but windy conditions will continue this afternoon with SW wind gusts 25-35 mph. Winds will come down this evening as mixing ceases, and become light and variable overnight. Cloudbases will range from 3500-5000 ft this afternoon through early tonight ahead of a weak front.
By early tomorrow morning, a weak front sinking south into the northern Carolinas will bring decreasing ceiling heights and increasing chances for showers. The front will stall somewhere near the Pamlico River/US 264 corridor and eventually lift northward late tomorrow. The best chances for seeing MVFR ceilings will be along and north of this front, and ceilings should drop to 2000-3000 ft tomorrow morning along and north of US 64 including KPGV. Farther south down to US 70, there are moderate chances of MVFR ceilings developing, but at exactly what time and for how long is uncertain at this time. South of US 70, VFR conditions should hold on through the day tomorrow.
Outlook: Periods of rain and lower CIGs in and out of the forecast late week into the weekend with a cold front approaching ENC and a developing low traveling along the boundary later in the weekend.
Wave guidance remains well underdone with the swell being produced by a strong low pressure system currently off the Grand Banks. Long period swell continues around 6 to 7 feet with periods of 12 to 13 seconds early this morning from Diamond Shoals northward. Do expect the long period swell to slowly subside to day as the low pushes eastward across the central Atlantic, however a system passing to the north will serve to tighten the pressure gradient bringing increasing SW winds bringing an increasing wind chop with combined seas building up to 6-9 ft peaking late this afternoon and evening. Sw winds are forecast to increase to around 10-20 kt across the sounds, rivers and northern coastal waters where below normal water temperature will bring a more stability near the surface, but near the warmer Gulf Stream waters, SW winds are expected to be around 15-25 kt with gusts to around 30 kt. In fact, Diamond Buoy, where water temps are reported as 72deg, has been reporting winds around 20 kt with gusts to near 30s kt early this morning.
Outlook: Conditions improve Thursday and Thursday night but another system passing to the north could bring SCA conditions to portions of the coastal waters again on Friday, most likely near the warmer Gulf Stream waters. A stronger low pressure system is forecast to impact the coastal waters on Sunday.
Nc, high surf advisory until 3 pm EST this afternoon for ncz204- 205. Marine, small craft advisory until 8 am EST Thursday for amz150. Small craft advisory until 11 am EST Thursday for amz152-154- 156-158.
