Area Forecast Discussion

WHAT HAS CHANGED

Updated aviation discussion.

KEY MESSAGES

1) Unsettled pattern through much of this week with at least a risk of strong to severe thunderstorms Wednesday until cold front crosses the area Thu. The main concern is the potential for heavy rain and flash flooding early Thursday through Thursday evening. Localized flood threat could continue Friday into the weekend.

2) After the strong front moves through the area Thursday, a brief reprieve from the heat, though showers and tstorms chances remain above climo until next weekend keeping daily localized flooding concerns in place.

DISCUSSION

KEY MESSAGE 1...Convection has waned quickly with loss of heating this evening. Iso shower/storm will be possible overnight, with best chances across the northern tier.

Biggest change today has been the slight delay compared to the 00Z suite of the frontal passage with the front not getting into the area until Thurs which has slightly delayed the heaviest precip until Thursday across ENC.

As we get into Wed night/Thurs and into this weekend, previously mentioned frontal boundary will track across the area Thurs and stall offshore with multiple mid level shortwaves tracking across the Mid-Atlantic into this weekend bringing elevated rain and thunderstorm chances to ENC over the next several days. Moisture increases ahead of this front with low to midlevel flow opening up moisture advection channel from the E side of what is now Tropical Storm Bertha. The National Hurricane Center continues issuing advisories for Bertha, but poses no tropical threat to ENC at this time, as it is forecast to meander slowly W across the Nern Gulf of America. The greatest risk for strong to severe thunderstorms will be Wed associated with a prefrontal trough, with the threat shifting to more of a hydro threat Thurs.

For Wed expect leftover cloudcover in the morning to mix out and lift into the afternoon hours. With a warm and moist environment in place across ENC through the day, this is forecast to allow for MLCAPE values to reach 2000-3000 J/kg in the afternoon hours. With a prefrontal trough likely setting up across ENC out ahead of the incoming front and the seabreeze moving inland this should be the focus for isolated to widely scattered showers and thunderstorms once again with activity near the coast in the morning and moving inland as the afternoon wears on. Once again there would be a low end threat for a wet microburst or strong downdraft wind gust (40-60 mph) within the strongest storms. ENC is once again in a marginal risk for severe thunderstorms tomorrow with a sliver or NW'rn Martin County in a slight risk (levels 1 & 2 of 5). The severe risk decreases greatly on Thurs as ongoing rain and cloudcover likely inhibits instability, but this threat then transitions to a flash flooding risk.

Out ahead of the strong front, moisture is forecast to pool in ENC. This will allow the already high PWATS of around 2" to increase further closer to 2.25-2.75" on Wed and persist across the area through Thurs. As mentioned above, latest guidance has slowed slightly with the frontal passage with this front likely not entering into the area until Thurs morning. All available guidance has showers and thunderstorms developing and training along and just out ahead of the slow moving front Thurs. With PWAT's well over 2", a deep warm cloud layer, long skinny CAPEs, and ample moisture forecast across ENC the environment will be primed for a flash flooding risk. This risk begins Wed and maximizes Thurs. WPC currently has the area under a slight risk for flash flooding (level 2/4) for Wednesday with general rainfall amounts between 0.25-0.75" possible with the highest amounts focused along the northern tier of counties.

However, as we get into Thurs most available deterministic and AI guidance is suggesting 24 hour rainfall totals between 2-4" with locally higher amounts possible across ENC. This is supported by the output from the ECMWF EFI where we are exceeding the 80th/90th percentile and seeing a SOT of 1-2 for 24 hour QPF across the area which is indicative of a potential extreme event across the area for 24 hour rainfall totals on Thurs. Heaviest amounts look to be focused north of Hwy 70 with lower amounts noted along the Crystal Coast. This coincides with Ensemble and NBM probs with a 40-70% chance of seeing greater than 2" of rainfall over 24hrs in these areas. As a result WPC has place portions of ENC north of Hwy 70 under a moderate risk for flash flooding (level 3/4) with areas south of Hwy 70 still in a slight risk (level 2/4). Any shower or thunderstorm that develops will be an efficient rainmaker and rainfall rates of 2-3" an hour will not be out of the question which could overwhelm drainage and urban areas in a short amount of time resulting in a broader flash flooding risk Thurs.

KEY MESSAGE 2...By Thu night front is forecast to make it through the entirety of the land area of ENC, but still stall offshore. This will lead to mostly N-NEerly flow late week into the weekend, cutting down on the heat (low to mid 80s/upper 60s splits into the weekend). Severe threat appears minimal behind the midweek front, but the multi day period of showers in the forecast could lead to hydro issues as precip will compound on itself so the threshold for additional flash flooding will be lower Fri into the weekend. We do look to finally dry out by early next week as ridging builds across the region but the next few days certainly look to be the wettest of 2026 for now.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/

VFR conditions across the terminals early this evening. SW'rly winds will remain elevated through tonight with sustained winds around 10-15 kts and gusts up around 20-25 kts. Expect these winds to help keep the fog threat down. Low level stratus possible, which could bring periods of MVFR between 9-15z. Any lower stratus that develops should lift with mixing by mid morning. Iso to widely scattered showers and storms expected in the afternoon and evening. Will leave out of TAFs for now. Better shower chances after 00z.

Outlook (Wed night through Sunday): A stronger front approaches late Wed and into Thurs, renewing stronger shower and thunderstorm chances WED. This front will stall offshore on Thurs evening where it will linger into the weekend, keeping rain and subVFR flight cat threat up through this weekend.

MARINE

Made some slight tweaks to the forecast over the next 24 hours but in general ongoing SCAs remain across all waters as of this updated with SW'rly winds at 15-20 kts and gusts up to 25 kts ongoing. The pressure gradient tightens this evening as a strong front begins to approach from the N and W allowing winds to increase further to 15-25 kts with gusts up to 30 kts across all waters this afternoon with 5-8 ft seas. Have upgraded the gale watches to warnings across the outer coastal waters north of Ocracoke Inlet as this is where I have the highest confidence in seeing wind gusts in excess of 35 kts. Have placed a strongly worded small craft across the Pamlico Sound as well as while there could be occasional wind gusts to 35 kts expect this to be a bit more infrequent. Elevated winds and seas persist through Wed out ahead of the approaching front. Showers and tstorm chances become confined to the GStream waters overnight tonight.

Outlook (Wednesday night through Sunday): For the outer waters, elevated winds and seas will continue into Thurs. This is in association with the aforementioned front that is forecast to cross regional waters Thurs, keeping elevated winds and seas in place and increased tstorm chances. Front moves through by Thurs afternoon and evening with winds shifting to a NE'rly direction and easing to a 10-15 kts with seas falling to 2-5 ft thus ending the SCA threat by Thurs night. More benign boating conditions outside of a scattered shower and thunderstorm threat is forecast from Fri through the weekend.

MHX WATCHES / WARNINGS / ADVISORIES

NC...Beach Hazards Statement until 8 PM EDT this evening for NCZ195- 196-199-204-205. MARINE...Small Craft Advisory until 11 PM EDT Wednesday for AMZ131-230- 231. Small Craft Advisory until 8 AM EDT Thursday for AMZ135-150- 156-158. Small Craft Advisory until 2 AM EDT Thursday for AMZ136-137. Small Craft Advisory until 11 AM EDT Thursday for AMZ152-154. Gale Warning until 11 AM EDT Wednesday for AMZ180. Gale Warning until 11 AM EDT Wednesday for AMZ182-184.