Marine Weather and Tide Forecast for Salvo, NC

NEAR TERM /UNTIL 6 AM FRIDAY MORNING/
As of 2200 Thursday...Convection has reached far NWern reaches of the FA. Very minor adjustments to grids. Forecast tracking well. Instability on the order of 3kJ/kg will remain in place until the front pushes through. Severe threat sharply diminishes from N to S across the FA as cells get further displaced from the greater upper level support of the trough aloft well to the N. May end up extending the watch for another hour or two.

Previous Disco as of 2000...Issued Severe tstorm watch for the first part of tonight; initial end time of 03Z. Copious amounts of CAPE abound and the the 00Z sounding confirms our suspicions that models are under-doing the energy on tap over the area despite the marine layer in the low levels behind the seabreeze.
00Z sounding shows CAPE in excess of 5000J/kg. Only major adjustment of forecast was to transpose the PoP forecast +1-2hr.
Everything else is remaining well on track.

Previous Disco...

Key Messages:

- Hot and humid with potentially dangerous heat indices across the coastal plain through this afternoon

- Strong to severe thunderstorms possible tonight along a passing cold front

Latest observations show a couple of isolated showers along the seabreeze, but radar is expected to remain relatively quiet until later this evening when a potent cold front will cross into our western counties. The atmosphere is primed to support strong to severe thunderstorms with MLCAPE on the order of 3000-3500 J/kg and deep layer shear between 25-35 kt. The main concern along the line will be damaging wind gusts, but large hail and tornadoes can't be ruled out given modest lapse rates of 6-6.5 C/km and increasing low level SRH. Heavy rain will also be possible given the anomalously moist airmass in place (PWATs around 2").

Given the above, SPC has the northwestern tier of the CWA in a Slight Risk (level 2/5) with the rest of the CWA in a Marginal Risk (level 1/5) for severe weather.

The line will be moving into a less favorable environment as it progresses eastward, but the severe threat will last all the way to the coast, pushing offshore by early tomorrow morning.

SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/
As of 3:40 PM Thursday...Quieter conditions take over tomorrow in the post-frontal air mass. Tonight's cold front will stall near the coast until tomorrow afternoon before dissipating and giving way to weak northerly flow. Highs will reach the upper-80s across the coastal plain and mid-80s along the OBX. With dewpoints a few degrees lower as well, heat indices should max out in the low to mid 90s. A smorgasbord of sea, river, and sound breezes will develop in the afternoon and be a source of convergence for scattered showers and thunderstorms through the evening hours.

LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/
As of 230 PM Thu...

Key Messages

- Dangerous heat and humidity develops early next week. Heat indices likely to reach 105 or more Monday through Thursday, with the potential for heat indices to around 110 degrees

Friday night and Saturday...Weak flow continues Saturday as high pressure strengthens both inland and offshore creating a local weakness in the pressure gradient. Building heights and increasing humidity are expected with light onshore flow developing, and highs will reach the upper 80s to low 90s across Eastern NC. The weak sea breeze may be able to provide enough convergence for an isolated shower or thunderstorm, with the best chances for this from New Bern south.

Sunday through Wednesday...A very strong upper level ridge will build over the Mid-Atlantic Sunday, and won't budge through late next week. This will keep the area mostly dry until Wednesday when the ridge begins to break down. Initially the highest low level heights will be to our north and west, but heights will build further locally by Monday. This will result in dangerous heat and humidity building across the region for a several day stretch. We begin to ramp up Sunday, with highs expected in the low to mid 90s, with heat indices 100-105. Monday through Wednesday temps will climb into the mid to upper 90s, with heat indices soaring to 105-110+.

With strong subsidence due to the upper level ridge of high pressure, no relief from the heat is anticipated from afternoon thunderstorms, and the cumulative mutli-day (and all day)
effects from the heat may be underestimated.

AVIATION /02Z FRIDAY THROUGH TUESDAY/
SHORT TERM /through Friday/...
As of 1940 Thursday...VFR flight cats with SKC where the seabreeze has pushed through with diurnal CU left ahead of it.
Predominantly VFR flight cats are expected but subVFR potential exists when a broken line of storms associated with FROPA passes through the area, inland terminals ~2-3Z. Some of these storms could be strong to severe, and a severe tstorm watch has been issued through 03Z. Gusty winds and heavy rains most likely, although some hail can't be ruled out. Rain clears rapidly from W to E through the overnight and early morning with mid and high clouds lingering just past sunrise. Winds become light and NWerly behind FROPA. VFR expected all day FRI with diurnal cu field ahead of seabreeze and some potential for seabreeze showers/storms in afternoon for coastal terminals.

LONG TERM /Friday night through Monday/...
As of 3 AM Thu...Aside from the threat of temporary restrictions to due scattered thunderstorms Friday, good flying conditions are expected through Monday with VFR prevailing and high pressure building in.

MARINE
SHORT TERM /through Friday/...
As of 3:50 PM Thursday...Marine conditions will continue to deteriorate through tonight as the gradient becomes more pinched ahead of an approaching cold front. Latest obs show southwest winds at 20-25 kt gusting to 25-30 kt. Gusts to around 30 kt will become more widespread across the waters tonight with seas building to 5-6 ft (5-7 ft central waters). By tomorrow morning, will become light and variable and seas will drop to 3-4 ft.

Strong to severe thunderstorms will be possible late tonight/early tomorrow morning with strong wind gusts and torrential rain being the main concern, with hail and waterspouts possible as well.

LONG TERM /Friday night though Tuesday/...
As of 230 PM Thu...An extended period of great boating conditions are expected Friday night through the middle of next week. High pressure weakly builds in Saturday with winds variable in the morning, becoming SE 5-10 kts in the afternoon.
Winds become S at 5-10 kts Sunday, then W/SW 5-15 kts Monday night becoming S/SW at 5-10 kts by Monday afternoon. A weak trough dips into the northern waters early Tuesday bringing variable winds less than 10 kt here, otherwise W winds around 5-10 kts becoming S/SW by the afternoon elsewhere.

Seas will be 3-5 ft Friday morning, and then subside to 2-3 ft for the rest of the period.

MHX WATCHES/WARNINGS/ADVISORIES
NC...None.
MARINE...Small Craft Advisory until 2 AM EDT Friday for AMZ131-230.
Small Craft Advisory until 4 AM EDT Friday for AMZ135.
Small Craft Advisory until 3 AM EDT Friday for AMZ137-150-231.
Small Craft Advisory until 9 AM EDT Friday for AMZ152-154-156- 158.