textproduct: Newport/Morehead City

WHAT HAS CHANGED

Aviation discussion updated.

KEY MESSAGES

1) A cold front will continue to push through the area this afternoon bringing a chance of showers and thunderstorms.

2) Warm and mostly dry conditions expected for much of the upcoming week.

DISCUSSION

KEY MESSAGE 1...A cold front will continue to sink southward through the area this afternoon and early evening. Showers and storms continue to blossom near the Albemarle and Pamlico Sounds this afternoon. West to northwest low-level flow should tend to limit the strength of convergence along the front. However, as the front encounters the developing seabreeze, there should be a local enhancement to low-level forcing, especially along and south of HWY 70. This is the area where the best chance for sustained, deep convection exists. The risk is conditional on sufficient low- level forcing, but should this occur, a short- lived risk of strong to marginally severe thunderstorms may develop thanks to elevated deep layer shear (~35kt) and moderate instability (MLCAPE up to 1500J/kg). Machine learning guidance isn't all that excited about this potential, and this likely speaks to the conditionality of the threat. This risk will quickly end from north to south as the front shifts off the Crystal Coast by sunset.

KEY MESSAGE 2...Guidance continue to trend stronger with an upper level ridge that will be expanding across the Southern U.S. this week. In fact, ensemble guidance is now forecasting 500mb heights around 600dm with this ridge, the strength of which is very unusual for this time of year. Normally, this would spell anomalous heat for ENC. However, a pocket of "cooler" thicknesses is forecast to be over the Carolinas associated with the post-frontal northeasterly flow regime, especially Tuesday and Wednesday. While it will be mostly dry, those cooler thicknesses may shield ENC from the anomalous heat that other parts of the South will experience. That pocket of lower thicknesses may begin to erode by the end of the week, with temperatures warming by then. However, guidance differ on when/if this will occur.

AVIATION /00Z TUESDAY THROUGH SATURDAY/

VFR conditions forecast through the period. Showers and thunderstorms associated with a southward moving cold front have since pushed offshore and outside of some mid level clouds over the next few hours mo clear skies are forecast tonight across all terminals. Dry air and a light but steady NE wind should preclude any fog threat tonight as well. Steady NE winds will continue through the day on Tue with partly cloudy skies as high pressure begins to build over the area.

Outlook (Tue night through Sat): High pressure builds in through the middle of the week with mostly VFR conditions expected. The high should also limit precip chances through late week.

MARINE

Latest obs show NE-NW winds 5-15 kt with seas 2-4 ft. A cold front will continue to sink southward through the waters this afternoon and early eve. N-NE winds will surge to 15-25 kt behind the front, peaking this evening then gradually diminishing late tonight into Tuesday. SCAs continue for the coastal waters, sounds and the Neuse/Bay Rvrs. Seas will build to around 5-8 ft late tonight with highest seas across the Gulf Stream. Wave guidance is typically underdone in NE flow and manually adjusted seas up 1-2 ft this afternoon into Tuesday, especially across the northern waters.

Outlook (Tue night through Sat): An extended period of northeasterly flow is expected through at least Wednesday or Thursday. Winds are forecast to lay down below 25kt, but elevated seas may linger for much of the week, especially with the contra flow against the Gulf Stream waters. For the near- shore coastal waters, elevated seas will likely linger through mid-week. Lighter winds Fri and Sat with seas mainly 2-3 ft.

MHX WATCHES/WARNINGS/ADVISORIES

NC...None. MARINE...Small Craft Advisory until 2 AM EDT Tuesday for AMZ131-230-231. Small Craft Advisory until 11 AM EDT Tuesday for AMZ135-137. Small Craft Advisory until 2 PM EDT Tuesday for AMZ150. Small Craft Advisory until midnight EDT Wednesday night for AMZ152-154. Small Craft Advisory until 8 PM EDT Tuesday for AMZ156. Small Craft Advisory until 8 PM EDT Tuesday for AMZ158.