textproduct: Newport/Morehead City

WHAT HAS CHANGED

Gale Warnings issued for waters between Cape Lookout and Cape Hatteras. Small Craft Advisory reissued for waters north of Oregon Inlet.

KEY MESSAGES

1) Increasing clouds with rain ongoing and extending into tonight.

2) Growing signal for a fast moving low traversing the eastern CONUS early next week bringing a risk of brief rainfall.

Aviation...Widespread IFR/LIFR conditions are expected tonight through Friday.

Marine...SCA conditions expected today into tomorrow with Gales likely between the Capes over Gulf Stream waters. Next period of SCA conditions possible next Monday into Tuesday.

DISCUSSION

KEY MESSAGE 1...ENC remains in steady southwesterly flow this morning with persistent high pressure offshore and cold front associated with Arctic Canadian low pressure extending into the Great Lakes and Midwest. Band of light rainfall is transiting our northern tier of counties aided by lift from an embedded shortwave in zonal flow aloft.

Cold front associated with the Canadian low will approach from the west today into Friday. Main slug of precipitation is more likely later this morning and Thur night as main trough axis and surface frontal boundary make their approach. Some limited thunder potential will be confined to near the Gulf Stream, but there is a low risk some convection could graze the Crystal Coast overnight into Friday morning. Heavier precipitation is favored closer the VA border, but odds of at least a quarter inch of rain sit between 80-90% and 50-60% for half an inch.

KEY MESSAGE 2...Once the Friday front clears through a few dry days are expected for the weekend as high pressure extends in from the north. The next potential system will come through the area early next week as a quick moving low zips across the central plains and mid-Atlantic. Precipitation amounts look to be a bit lower for this system compared to today's. Enough spread remains in model guidance on timing that chance PoPs were maintained this morning.

AVIATION /12Z THURSDAY THROUGH MONDAY/

A warm front is slowly lifting north through ENC this morning, and is forecast to be just north of the area later today. Along and north of the front, there will continue to be periods of RA and MVFR VIS (3-5SM). CIGs should continue to steadily lower as well, although this has been a bit slower to occur than previously forecast. CIGs will probably hover around 2-5k ft for much of the day. Later this evening, a cold front will push south through the area, and this is expected to be accompanied by widespread IFR/LIFR CIGs along with reduced VIS in RA and BR. Confidence in the timing of LIFR is highest at KISO and KPGV, and I've added that to the TAFs there. Further south, LIFR is likely, but confidence is lower regarding the timing, and the TAFs will only reflect IFR conditions for now. There will be a low-end TSRA risk this evening (10-20%), but the risk is too low for a mention at any TAF site.

In the wake of the above-mentioned warm front, southwesterly winds will increase, eventually becoming gusty later this morning and continuing into this afternoon. The KMHX Vad Wind Profile shows WSW low-level jet winds of 40-45kt, which is higher than all available guidance. Because of this, LLWS guidance is likely under doing the potential, and I added in LLWS for all TAF sites for a few hours this morning.

Outlook: Guidance differ on the evolution of this evening's cold front, with differences focused on whether or not low pressure develops along the front. If a low develops, this could prolong IFR/LIFR conditions into Saturday. Conversely, if a low doesn't develop, IFR/LIFR conditions would end sooner. Either way, periods of RA will continue into at least Friday, but could last into Saturday if a low develops.

MARINE

Latest obs show SW winds 10-15 kt over the cooler nearshore waters and 15 kt gusting around 25 kt over the outer waters near the Gulf Stream, with seas 2-4 ft north of Oregon Inlet and 4-6 ft south. Gradient will tighten again today ahead of the cold front with another round of SCA conditions likely across the Pamlico Sound and northern coastal waters. The probability of Gales has increased quite a bit this morning with several members of hi-res guidance advertising potential gusts of up to 35-40 kt. Some members have a history of overdoing mixing especially over coastal waters, but this does seem more plausible over the Gulf Stream especially given a potent LLJ expected to develop later today. Thus, opted to put up a Gale Warning for the waters in Raleigh Bay. SCA remains in effect for all other offshore waters.

Wave guidance has been under-performing observations during the past few Gales, so manually adjusted forecasts upward a couple feet to show up to 10 feet for the outer central waters. If stronger winds closer to 40 kt are realized this could still be conservative by a couple of feet.

Outlook: Poor boating conditions likely to persist for offshore waters into Friday before the front crosses the region. The front moves through Friday, with winds becoming NE 10-20 kt late Fri into the weekend. Next period of SCA likely Mon and Tuesday in increasing northeasterly flow.

MHX WATCHES/WARNINGS/ADVISORIES

NC...None. MARINE...Small Craft Advisory from 11 AM this morning to 10 PM EST this evening for AMZ135. Small Craft Advisory from 3 PM this afternoon to 10 PM EST this evening for AMZ150. Small Craft Advisory until 10 AM EST Friday for AMZ152-158. Gale Warning from 11 AM this morning to 10 PM EST this evening for AMZ154-156.