textproduct: Newport/Morehead City

SYNOPSIS

A strong low pressure system will move across the Carolina coast tomorrow. High pressure then rebuilds into the area from the north through midweek before another low pressure system impacts the region late next week.

NEAR TERM /UNTIL 6 AM THIS MORNING/

As of 3 PM Mon...

Key Messages...

- Rain chances increasing overnight, with locally heavy rainfall possible

- A few thunderstorms possible overnight with a very low risk of a strong storm or two

Latest analysis this afternoon shows mainly zonal mid-level flow over the southeastern CONUS including the Carolinas, while a positively tilted trough digs into the southern plains. At the surface, wedge of high pressure remains locked in place over much of the mid-Atlantic while a stalled front continues to sit over the northern GoA.

Plume of anomalously deep Gulf moisture is expected to advect across much of the southeast and into the mid-Atlantic overnight as mid-level trough continues to dig into the southern MS River Valley. A PWAT of 1.5 - 1.75" may not seem significant in the summer, but in early December these values are in the 95% percentile of climatology. The progression of the trough will also result in multiple waves of low pressure deepening along the aforementioned frontal boundary, one of which is forecast to lift just inland across our FA Tuesday.

Stratiform rain is expected to begin lifting across the FA after midnight with strengthening WAA, while convection will develop over the warm Gulf Stream and drift towards the coast. The bulk of this activity will remain offshore, but some convection could bleed over and maintain itself over the immediate coastal areas from Onslow County towards Hatteras Island, as indicated by HREF probs of 500 J/kg CAPE confined to this area. Severe threat is marginal as axis of highest instability is largely divorced from axis of highest helicity. Still, with effective shear of 35-40 kt and looping low-level hodographs cannot completely rule out a risk of a damaging wind gust or brief spin-up drifting onshore. Otherwise, main threat from convection will be heavy rainfall. This should be largely beneficial given our recent drought, but urban sites and areas typically vulnerable to quick ponding of water may see some minor flooding.

Lows in the mid 30s will occur around midnight with temps steadily arising ahead of the approaching low.

SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/

As of 300 PM Monday...

Key Messages...

- Ongoing rain in the morning will taper off mid to late afternoon

Rainfall will be ongoing at sunrise tomorrow morning with ongoing WAA and surface low rapidly lifts northwards towards New England. Convective threat window likely to end around midday as effective shear and low level SRH collapses. Rainfall will end from west to east, likely clearing the Outer Banks by sunset Tuesday. Storm total rainfall ranges from 1-1.5" inland to around 2" along the coast, although probability of exceeding 2" is as high as 45-50% for the Outer Banks. Wide spread in temperatures tomorrow, ranging from upper 60s along coastal areas to only low to mid 50s west of Highway 17.

Gradient winds associated with the low will churn up seas, posing a rough surf threat mainly between Cape Hatteras and Cape Lookout and threaten dune structures along Highway 12 - see TIDES/COASTAL FLOODING section for details.

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/

As of 1 PM Monday...

Key Messages

- High pressure brings dry conditions and below normal temperatures Wednesday and Thursday

- Another low pressure system is expected to impact the region late in the week.

PoPs will quickly drop off as the low pulls away from the coast, leaving the area dry Tuesday night as high pressure builds back in and strong CAA develops. Temps will then tank, ranging from the upper 20s across the coastal plain to low 40s along the Outer Banks. High pressure will keep things cool and dry through Thursday with highs rebounding to the mid 50s.

PoPs will increase on Friday as a northern stream shortwave digs into the Plains and a low lifts along the southeast coast. With inland temps near freezing Friday morning, there's potential for a brief window of a rain/snow mix. Latest trends as of early Friday afternoon appear to be leaning towards a slightly slower and weaker late week system. Uncertainty still remains regarding how close to shore the low will track, but trends will continue to be monitored. In particular, PoPs may need to be adjusted downward should current model trends continue.

AVIATION /06Z TUESDAY THROUGH SATURDAY/

As of 100 AM Tuesday...Low pressure will develop off the Southeast coast this morning and track along the coast today. Cigs will continue to lower through the early morning hours with sub- VFR conditions currently lifting into the area. Precip is soon to follow, after 9Z. IFR/LIFR conditions with moderate to heavy rain will then move through after 11z. Strengthening low level jet is also expected after 11z with LLWS concerns through the morning hours. Stratiform rain expected for most terminals, but some convection is possible for OAJ, EWN and other coastal terminals. The low is expected to lift away from the area through the afternoon with precip beginning to taper off from W to E however IFR/LIFR conditions expected to linger through 22Z, after which skies start to break up.

Outlook: High pressure builds back into the area Wednesday and Thursday with pred VFR conditions expected. Another system Friday and Saturday may bring sub-VFR conditions again.

MARINE

As of 300 PM Monday...

Key Messages...

- Gale Warning in effect from Oregon Inlet to Surf City Tuesday morning and afternoon; SCA for Pamlico Sound and northern offshore waters

Current observations depict persistent north to northeasterly winds across area waters at 15-20 kt with gusts of 25-30 kt over the warmer Gulf Stream waters. Seas have refused to lay down today, still at 6-7 feet for all zones.

Forecast calls for further deteriorating conditions early tomorrow morning extending into Wednesday as deepening coastal low lifts northward across eastern NC. Pressure gradient between the low and stubborn wedge of high pressure inland will result in a brief but high confidence period of Gales over the western wall of the Gulf Stream, and a Warning has been hoisted for these zones starting at 13z tomorrow. Elsewhere, rapidly cooling nearshore and soundside waters will greatly hamper gust potential, with SCA most likely across central and eastern portions of Pamlico Sound, as well as the Croatan/Roanoke sounds.

Outside of the Gale warnings, SCA for northern waters is being extended through Wed morning. There will be a brief period of sub-6 foot seas during the overnight before increasing winds push them back up after sunrise. Pamlico Sound will also see a lull overnight before conditions deteriorate in the morning in tandem with the offshore Gale surge. Another brief lull is likely in the afternoon before winds increase again out of the northwest behind the low.

Outlook: SCA likely ongoing for most waters Tues night as winds veer northwesterly behind the departing low before diminishing Wed morning. weekend as another low is forecast to move up the coast.

TIDES/COASTAL FLOODING

As of 1 AM Tuesday...A strong low pressure system moving through North Carolina today will bring elevated winds and seas. This comes as we enter a king tide cycle today (12/2) through Monday (12/9) of next week. Areas with vulnerable dune structures along the Outer Banks have the potential to see minor coastal flooding, heightened during Tuesday evening's and early Wednesday morning's high tides. Current expectations are that cool nearshore waters should help confine strongest winds to several miles offshore limiting more impactful rises. However, developing rough surf could result in some overwash issues in areas with known dune vulnerabilities, especially for Ocracoke Island.

A High Surf Advisory has been issued Tuesday 10AM to 10 PM as breaking waves of 6-9 ft could cause hazardous surf conditions and localized beach erosion between Cape Hatteras and Cape Lookout.

MHX WATCHES/WARNINGS/ADVISORIES

NC...High Surf Advisory from 10 AM this morning to 10 PM EST this evening for NCZ196-204-205. MARINE...Small Craft Advisory from 6 AM this morning to 4 AM EST Wednesday for AMZ135-231. Small Craft Advisory until 10 AM EST Wednesday for AMZ150. Gale Warning from 8 AM this morning to 3 PM EST this afternoon for AMZ152-154-156-158.