textproduct: Newport/Morehead City

WHAT HAS CHANGED

The Small Craft Advisory was expanded north to include the coastal waters from Duck to Oregon Inlet through early this evening.

KEY MESSAGES

1) Increased risk of scattered to numerous showers and thunderstorms through Monday, some of which could be strong with gusty winds, a risk of heavy rainfall, and scattered instances of flooding/flash flooding.

2) Brief reprieve from the dangerous heat early next week, then hot and humid conditions return by the end of the week.

DISCUSSION

KEY MESSAGE 1...A wavy frontal boundary stretches west to east across the Southeast U.S. early this morning, with areas of low pressure riding east along it. Weak to moderate instability, anomalous moisture, and areas of enhanced convergence is expected to favor bands of training convection capable of intense to, at times, extreme rainfall rates (potentially as high as 2-4"/hr at times). While not everyone will get these rates, there will be an increased risk of flooding and flash flooding where those occur, especially if they develop over urban areas. Short-term guidance differ on the placement of these bands, but the general gist is that the heaviest rainfall will be focused across northeastern sections of ENC this morning, followed by a shift southwest with time towards the HWY 70 corridor and then eventually on towards the Crystal Coast. Slightly drier air working in from the north should eventually focus the heavy rainfall footprint across far southern sections of ENC by Tuesday, with conditions improving by Tuesday night as the low and frontal zone shift further offshore.

While the main concern appears to be shifting primarily to hydro concerns over the next couple of days, there may be just enough instability and shear to support a few stronger cores capable of 30- 50 mph winds. The risk of severe thunderstorms appears to be decreasing, however.

KEY MESSAGE 2...Low pressure developing off the coast of NC today is expected to keep a "cooler" northeasterly flow going across ENC through Tuesday. This should keep temps below normal for a couple of days, and consequently lower the heat risk. This looks to be short-lived, though, as a warming southwesterly flow regime returns mid to late-week. Guidance continue to show a strong signal for above normal temperatures and an increased heat risk once again.

AVIATION /06Z MONDAY THROUGH FRIDAY/

Areas of moderate to heavy RA are expected to continue to impact parts of ENC over the next 24 hours. Within the area of RA there will be scattered TSRA at times, along with widespread sub-VFR conditions. During the heaviest RA, IFR/LIFR VIS will be possible. Additionally, there will be a longer-duration risk of IFR/MVFR CIGs that is likely to last beyond the next 24 hours.

Outlook (Sunday through Friday): Moisture and lift along a stalled front should continue to support periods of SHRA into Tuesday with periods of low CIGs (IFR/MVFR). A more predominant period of VFR conditions looks to return by the middle of next week.

MARINE

Low pressure is forecast to translate east along a stalled front over the next couple of days. On this track, the low should pass through the southern waters, which suggests the strongest easterly winds, and highest seas, will be focused across the central and northern waters. For those waters, seas of 4-7ft and winds of 15-25kt appear likely. A Small Craft Advisory remains in effect for the central coastal waters where confidence in impacts is the highest. Additionally, based on the latest observations and guidance, the advisory has been expanded north to include the northern coastal waters as well. Seas are already around 5ft early this morning there, and with the continued moderate easterly winds, should continue to build to around 6ft.

Outlook (Tuesday through Friday): Low pressure will slowly weaken and move east on Tuesday with high pressure building in mid to late week bringing improved boating conditions. Building southwesterly flow is expected by the end of the week.

MHX WATCHES/WARNINGS/ADVISORIES

NC...Beach Hazards Statement from 6 AM EDT this morning through this evening for NCZ196-203>205. MARINE...Small Craft Advisory until 8 PM EDT this evening for AMZ150. Small Craft Advisory until midnight EDT tonight for AMZ152-154.