textproduct: Newport/Morehead City

WHAT HAS CHANGED

No significant changes with this forecast package.

KEY MESSAGES

1) Dangerous heat and humidity persists across ENC into this weekend.

2) There is a chance for some strong thunderstorms later this weekend into early next week as instability builds across ENC.

DISCUSSION

KEY MESSAGE 1...Hot and humid conditions across the region today with temperatures in the mid to upper 90s inland from the coast and lower 90s along the immediate coast. Heat index values have reached around 100-110 this afternoon, highest along the coast where dew point temps are in the mid to upper 70s. Deeper mixing inland and brought dew point temps into the upper 60s to lower 70s keeping heat index values in the lower range. Will continue the Heat Advisory for much of ENC through the early evening hours.

Low level thickness will be similar across the are on Friday and expect similar high temps in the 90s once again. Low level flow continues out of the W to WSW Friday with deeper mixing allow for dew point temps to drop around 2-3 degrees from today's values, and while the Heat Risk continues in the major category, heat index values are expected to peak a few degrees lower, generally around 100-105. Will hold off on issuing a Heat Advisory for Friday at this time with only a small are expected to climb above 105 degrees and let following shifts evaluate further.

Low level thicknesses decrease several meters on Saturday with temps a few degrees less hot while dew point temps begin to creep back up resulting in another day with heat index values around 100-105 with the heat risk in the moderate to major range.

KEY MESSAGE 2...An upper level trough/mid level shortwave and surface front approaching from the north and west this weekend will increase shower and thunderstorm chances Saturday and Sunday across ENC. Latest trends is for the front to approach our northern zones Saturday evening and push through the area Sun morning. This would act to bring best precip chances to ENC Sat afternoon and overnight with chances then waning through the day Sun from north to south. While instability has trended down, generally ranging from 1000-2000 J/kg of ML CAPE Sat and 750-1500 J/kg of ML CAPE Sun, with greater upper level support and deep layer shear values closer to 25-30 kts this weekend across ENC, could see a few stronger storms this weekend.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

Low pressure over northern Virginia will continue to push off to the east tonight, leaving behind an area of weakening low- level convergence into central/eastern NC. That convergence area may support a few SHRA or weak TSRA over the next few hours (ie. through around 06z). However, confidence in this activity actually developing is low, therefore we'll continue to keep out any mention in the TAFs. On Friday, a couple of upper level waves plus gradually increasing moisture may support a slightly higher chance of SHRA and TSRA, especially during the late afternoon and evening hours. Confidence in this activity is moderate, as there still appears to be some limiting factors for TSRA development. In light of this, we'll also continue to hold off on any TSRA mention in the TAFs for Friday.

A tightened gradient south of the Virginia low is helping support gusty winds at most TAF sites this evening. These conditions should continue for another 1-2 hours before decreasing as the low pulls away allowing the gradient to relax some.

Outlook (Saturday through Tuesday): As we get into the weekend as an upper level trough and associated surface front approaches increasing chances for showers and storms as well as sub-VFR conditions will be noted. Could see improving conditions on Monday.

MARINE

Currently seeing SW winds around 10-20 kt with seas around 3-5 ft. Winds will continue to increase this afternoon and evening as a low pressure area passes north of the area and a strengthening thermal trough inland with SW winds around 15-25 kt with gusts up to 30 kt and seas building to 4-7 ft. Winds will be strongest across the Pamlico Sound and coastal waters and have kept SCA's for these areas. Winds relax briefly Friday morning, but then tighten again Friday afternoon as a front approaches from the NW with SCA conditions expected to redevelop over the coastal waters south of Oregon Inlet.

Outlook (Saturday through Monday): Once again not much change in the forecast as conditions gradually improve Saturday, then will see a backdoor cold front drop through the waters late Saturday night and Sunday with winds becoming NE around 10-20 kt with seas building to 3-5 ft. A weak area of low pressure may form along the stalled front to the south Monday keeping E-NEly flow across the waters.

MHX WATCHES/WARNINGS/ADVISORIES

NC...Heat Advisory until 8 PM EDT this evening for NCZ045>047-080- 081-090-092-094-193>196-198-199-203>205. Beach Hazards Statement until 8 PM EDT this evening for NCZ195- 196-199-203>205. MARINE...Small Craft Advisory until 4 AM EDT Friday for AMZ135-150. Small Craft Advisory until 8 AM EDT Saturday for AMZ152-154- 156-158.