textproduct: Newport/Morehead City

WHAT HAS CHANGED

Have replaced central water small crafts with additional small crafts across all waters starting tonight.

Tuesday: Carrying a dry forecast for the area

Aviation Discussion has been updated.

KEY MESSAGES

1) Cold front approaches this afternoon and evening with chances for showers and thunderstorms area wide.

2) Cool and trending drier as a coastal low looks to remain off the coast Tue, Wed, and Thurs.

3) Heat returns this weekend

DISCUSSION

KEY MESSAGE 1... A warm start to the morning as mostly cloudy skies, a few showers, and temps in the 60s are noted across ENC. SW'rly flow at the surface will bring a warm and moist airmass to ENC today with temps getting into the upper 70s to low 80s. While at the same time moisture pools across ENC out ahead of an approaching cold front.

Upper level shortwave currently noted across the Ohio River Valley will dive SE'wards into the Carolinas today out ahead of a sharper positively tilted trough noted in the Northeastern CONUS. At the surface, cold front stretching from the Northeast SW'wards into Tennessee this morning is forecast to track SE'wards through the day tracking across ENC tonight. While there are some differences in timing of this front with the HRRR being the most progressive and the NAM being the least progressive, general expectation is for this front to track across ENC tonight quickly moving from north to south. While a few showers will be possible this morning well out ahead of this front with (20-40%) chance for showers, the main show will likely be later this afternoon into tonight where widespread 50-75% chance for showers and thunderstorms will be possible.

Out ahead of this front, SW'rly flow will advect mid to upper 60s dewpoints to ENC. As daytime heating maximizes, instability will build allowing for MLCAPE values between 500-1000 J/kg to develop this afternoon especially south of Hwy 264. At the same time deep layer shear values around 30-40 kts are forecast to overspread the area. This will result in scattered shower and tstm development across our northern zones first with this activity then tracking S though the afternoon and evening before pushing offshore tonight. Typically this would allow for some tstm organization but there are a few caveats to the tstm threat today. The first will be this mornings cloud cover and iso shower activity which may limit instability across ENC, which would then limit how strong storms get. The second is weaker lapse rates across ENC until late tonight. With all this in mind still can't rule out a stronger storm or two primarily after about 2PM until about 10PM with frequent lightning, gusty winds (40-50 mph), and small hail being the primary threats if a storms can take advantage of this marginal at best environment. With the front moving through tonight lows are forecast to be slightly cooler getting into the upper 50s to low 60s.

KEY MESSAGE 2... Previously mentioned positively tilted upper- level trough will swing across the Mid Atlantic on Tuesday, which will help keep a developing coastal low offshore. Guidance continues to get into better agreement that the surface low should remain well enough offshore 100-200+ miles to keep the area mostly dry through midweek. So, while there are technically showers in the forecast for Wed/Thurs, if trends continue, would not be surprised if these chances lowered on future updates given the setup. More notable than the precip will be the breezy northeasterly gradient winds, which could gust to 20-25 mph inland and 25-35 mph along the coast.

KEY MESSAGE 3...As we get into the end of the week, low offshore is forecast to push out to sea with high pressure building overhead Thurs and then becoming anchored off the coast this weekend. This will bring steady SW'rly flow, increasing low level thicknesses, and warming temps with highs forecast to get back into the 90s inland and 80s along the coast and OBX bringing a return to more summer like temps.

AVIATION /12Z MONDAY THROUGH FRIDAY/

Only minor tweaks to the aviation forecast as not much has changed. Have taken out any mention of MVFR ceilings this morning in the TAFs as latest obs show the entire area under VFR conditions and we should remain VFR until the afternoon shower and thunderstorm activity starts up. Otherwise similar thinking for this afternoon and overnight.

A modest increase in the potential for MVFR and potentially IFR vis/cigs is forecast in shower/thunderstorm activity this afternoon and evening. Threat starts from the north and pushes south through tonight. SCT SHRA and TSRA with reduced VIS and gusty/erratic winds are forecast along and just out ahead of the southward moving cold front. Behind the front there will be a northeasterly wind shift with gusts up around 20 kts inland and 25-30 kts along the OBX and immediate coast with these elevated winds persisting into Tue morning. Of note, where TSRA occur, the forecast environment appears supportive of a risk of 30-45kt downburst winds and small hail (<0.5" in diameter).

Outlook: Tuesday looks to remain dry, but it will be quite breezy throughout the day with NE gusts to 15-20 kt inland and 20-30 kt along the coast. Winds will remain out of the NE on Wednesday but gradually ease with a slight chance of showers (highest along the coast). Winds eventually shift to S'rly direction by late Thursday and into Friday and remain light. Predominantly VFR conditions are expected for the remainder of the period.

MARINE

High pressure is currently noted offshore this morning with a cold front noted to the north and west of our waters. Winds remain around 5-15 kts out of the SW, while seas have generally fallen to about 3-5 ft. As a result have ended the central waters SCA's that were out earlier in the evening.

5-15 kt SW'rly winds to continue for much of today out ahead of an approaching cold front while seas remain at about 3-5 ft though 4-7 ft seas will be found across the outer waters (20+ NM out). This however will change later this afternoon and into tonight as the aforementioned cold front approaches and quickly tracks across the area. Increasing shower and thunderstorm chances expected this afternoon and evening. A few of these storms could be strong in nature bringing a threat for locally elevated winds and seas to all waters. Then as the front tracks from N to S tonight, winds will quickly shift to a NE direction at 15-25 kts with gusts up around 30 kts while seas build to 6-10 ft north of Cape Lookout and 4-7 ft south of Cape Lookout. This will once again bring SCA conditions to all our waters starting tonight and persisting into Wed. There is a low end chance at a few gusts up towards 35 kts across our coastal waters south of Cape Hatteras on Tue but the threat was too low to include a gale watch for now.

Outlook: Hazardous marine conditions will continue to persist into midweek as a low develops off the coats and keeps the pressure gradient pinched. This keep NEerly winds gusting to 25-30+ kt Tuesday evening into Wed especially across our coastal/outer waters. Seas will also persist around 6-10 ft. Winds should drop below SCA criteria by Wednesday evening but elevated seas could persist into early Thursday.

MHX WATCHES/WARNINGS/ADVISORIES

NC...None. MARINE...Small Craft Advisory from 2 AM to 11 PM EDT Tuesday for AMZ131- 230-231. Small Craft Advisory from 5 AM Tuesday to 2 AM EDT Wednesday for AMZ135. Small Craft Advisory from 6 AM to 8 PM EDT Tuesday for AMZ136- 137. Small Craft Advisory from 2 AM Tuesday to 5 PM EDT Wednesday for AMZ150. Small Craft Advisory from 2 AM Tuesday to 5 AM EDT Thursday for AMZ152-154. Small Craft Advisory from 6 AM Tuesday to 2 AM EDT Thursday for AMZ156-158.