textproduct: Newport/Morehead City

WHAT HAS CHANGED

No significant changes.

KEY MESSAGES

1) Strong cold front to bring breezy and colder conditions this weekend, along with a risk of widespread frost/freeze conditions.

Marine: Gale-force winds to continue across the outer coastal waters through late this evening from Oregon Inlet south through Surf City.

DISCUSSION

KEY MESSAGE 1...A pair of cold fronts will traverse ENC over the next couple of days as an unusually strong upper level trough develops over the Eastern U.S. The first cold front is currently moving through central NC. This front will move across ENC between 4pm-10pm. Recent radar imagery shows scattered, high-based showers developing along the front, and hi-res guidance suggests some of this activity may make it into ENC this evening. While low-level moisture is lacking, modest mid-level moisture, weak instability, and strong forcing along the front appears to support this idea. In light of the potential, the chance of showers was slightly increased over the next several hours. No lightning has been observed yet, but a few strikes cannot be ruled out. Breezy southwest winds will continue for a few more hours ahead of the front, then a thump of winds behind the front is possible. Winds were increased for a few hours just behind the front to account for the enhanced mixing as strong CAA ensues.

The strong CAA will usher in a noticeably colder airmass compared to what we have had the past couple of days. This initial front will knock highs down into the 50s and 60s, with lows in the 40s and 50s. The second front, which will move through late Friday, will reinforce the cold airmass. In the wake of that front, highs will only manage to reach the 50s, while lows tumble into the 20s and 30s inland, and 30s and 40s along the coast. There was some consideration for a Freeze Watch for a part of the area Friday night. However, even the 10th percentile of guidance keeps most of the area above 32 degrees. While a few sheltered areas may fall below freezing, the risk of freezing temperatures looks more marginal Friday night. Additionally, while some areas will fall into the low to mid 30s, there should be enough wind to prevent frost development. Therefore, no frost/freeze headlines are planned for that time period. Looking ahead, there is a much better chance of frost/freeze conditions Saturday night and Sunday night as a strong surface high builds in and winds decrease. Headlines will likely be needed at some point this weekend, and potentially into early next week.

AVIATION /19Z THURSDAY THROUGH TUESDAY/

Forecast confidence is high over the next 24 hours.

A cold front will move through ENC between 21z-03z this evening. Gusty southwest winds ahead of the front will become westerly as the front moves through. A period of gusty northwest winds are then likely to occur for at least a few hours in the wake of the front. SCT to BKN mid-level clouds and isolated SHRA will be possible associated with the front as well. Throughout the 18z TAF cycle, VFR conditions are expected to prevail.

Outlook: Another cold front will move through ENC late Friday with another round of gusty winds, mid-level clouds, and a few SHRA. Lighter winds are then expected by early next week. Mostly VFR conditions are expected over the weekend and into early next week.

MARINE

Southwest winds have quickly increased to 15-25kt ahead of an approaching cold front this afternoon. These winds may build a little further, peaking now through around 12am-2am tonight. Gale- force gusts are ongoing across the outer southern coastal waters, and this risk is still expected to expand northeast across more of the central outer coastal waters. The Gale Warning covers this potential nicely, and no changes were needed with this forecast update. Closer to the coast, there will be a risk of 25kt winds through tonight, and a Small Craft Advisory remains in effect south of Oregon Inlet.

Where gale-force winds are ongoing, seas have already reached 5-8ft. Seas are expected to continue to build, and peak at 6-9ft south of Cape Hatteras. North of Hatteras, seas of 3-5ft are expected through tonight. Seas will begin to lay down to 2-5ft for all coastal waters by Friday afternoon.

A risk of scattered thunderstorms may accompany the cold front as it moves through the central and southern waters this evening. Areas of enhanced wind gusts may accompany any thunderstorm that develops.

Outlook: A brief decrease in winds and seas Friday afternoon will be short-lived as yet another cold front moves through Friday evening and night. This is expected to be accompanied by a northerly surge of winds. Guidance have backed off on the winds some with this surge, but there still appears to be a decent signal for 25kt+ gusts and elevated seas, especially north of Cape Hatteras. Additional, or new, marine headlines may be needed for that front. Winds and seas should lay down by early next week as high pressure builds in.

MHX WATCHES/WARNINGS/ADVISORIES

NC...None. MARINE...Small Craft Advisory until 10 AM EST Friday for AMZ152-154. Small Craft Advisory until 7 AM EST Friday for AMZ156-158. Gale Warning until 1 AM EST Friday for AMZ182-184-186-188.