Key MESSAGE 1, Hot and humid conditions will continue through the weekend, peaking this afternoon. Heat Adv continues for the area with heat index values 105-110 deg through early evening. Heat Advisories will also need to be considered daily SUN into the middle of next week, though we may see a dip in heat MON with greater coverage of rain helping bump MaxTs into the upper 80s and low 90s.
KEY MESSAGE 2, There are several factors expected to support an increasingly active pattern into next week.
Upper level troughing will continue to strengthen over the Eastern U.S. With ridging shifting away from the area. Persistent S-SWerly flow E of the trough, potentially with a subtropical connection, should act to enhance low-mid level moisture across the area. Meanwhile, heating of a moistening boundary layer should lead to sufficient instability and reduced inhibition in support of periods of convection.
At the surface, the front that sunk into the Albemarle Sound yesterday has lifted back Nward into VA, acting to "warm- sector" the entire FA for the weekend. Lee- side troughing and, eventually, a frontal boundary that will reach the FA by MON should provide areas of enhanced low- level forcing this weekend with gradually improving mid and upper level flow becoming more conducive to organized storm modes as trough aloft sharpens. Bulk of guidance shows a mostly dry daytime forecast with a dry at 850 remaining overhead until tonight. Though, some more excitable HiRes solutions show pockets of increased moisture shunted into the area from the high pressure offshore leading to SChc PoPs. Isolated showers and storms developing to the south and west early this afternoon, and may blossom a bit with the seabreeze in the next few hours. Main concern will be this evening, towards sunset with storms that develop W and N of the FA closer to the approaching front and with greater mid and upper level support. These storms are forecast to be weakening while they cross the Nern half of the FA from W to E. Should more organized cells persist, they will carry a threat of damaging wind gusts. As such, SPC has inland portions of the FA outlined in a Marginal Risk (lvl 1/5) of severe thunderstorms.
Sunday, the SFC front will enter and stall over the Nern half of the FA. Spc's day 2 outlook for SUN features a Slight Risk (lvl 2/5) for the bulk of the area. Moisture pooling and low level convergence will be maximized SUN afternoon into SUN night as the cold front approaches. Pwats peak on the order of 2 and 3/4in with increasing afternoon and evening instability through the weekend. Main concerns will be the potential for damaging wind gusts, heavy rain and freq lightning late afternoon into Sun night. Wpc has upgraded most of the region into Slight Risk for flood potential Sun.
Additionally, while guidance remains mixed, there is a modest signal for low pressure development across the northeastern Gulf. The National Hurricane Center has increased probability of development a bit to 30 40% over the next 2 days. Though no explicitly tropical impacts are expected from this system locally, this low could act to enhance rainfall along the SE coast by further increase Gulf moisture transport from its Eern half through early next week while SUN's front lingers across the region.
Tropics aside, deterministic and machine learning guidance continue to show a good signal for some strong to marginally severe thunderstorm potential during this period of active weather. Right now the signal is the strongest on Sunday. Though this could be dependent on convection tonight and how much destabilization is possible Sun. Given increased forcing from the approaching front and the potential tap of subtropical moisture, heavy rain and some hydro impacts may eventually be realized.
A stronger front is forecast to approach and cross the area WED into THU, posing the next threat for severe weather later in the forecast period. Spc and WPC currently have the area outlooked for potential stronger storms and heavy rain.
18z Saturday through Thursday VFR conditions across the terminals this afternoon with breezy SSW flow. Isolated showers and storms beginning to develop, which could temporarily impact the sites through this evening. Better convective chances will be later this evening, between 00-04z, with best chances at PGV. Low fog threat overnight with light SW breeze, though could see patchy lower stratus. Stratus probs look low (less than 10%), so will not include at this time. Better convective coverage expected Sunday afternoon and evening, which could lead to periods of sub-VFR. A few stronger storms are also possible, with potential for damaging wind gusts, heavy rain and frequent lightning.
Outlook (Sunday night through Thursday): The risk of TSRA increases Sunday night when a front enters and stalls over the area through early next week. Sub-VFR conditions can be expected along with the TSRA impacts.
Latest surface and buoy obs indicate S-SW winds 10-20 kt with seas 2-3 ft. Moderate SSW winds will increase to 20-30 kt this evening, peaking tonight around midnight. Scas continue for the Neuse/Bay Rvrs, Pamlico Sound and nearshore coastal waters. Over the outer coastal waters, a few gale-force gusts will be possible tonight into Sunday morning, but probs look low. Seas will quickly respond to the winds, building to 4-7 ft tonight. Moderate to strong SW winds will continue Sunday, stronger south of Hatteras with seas 3-6 ft.
Outlook (Sunday night through Thursday): SUN's front stalls over the area lingering through early next week. Keeping elevated winds, seas, and tstorm chances in the forecast. For the outer waters, elevated winds and seas may last for much of the week. A stronger front is forecast to approach and cross regional waters mid to late week, bringing another round of strengthening SW winds and tstorm chances, mainly later Tue and Wed.
Nc, heat advisory until 8 pm EDT this evening for ncz029-044>047- 079>081-090>092-094-193>196-198-199-203>205. Marine, small craft advisory until noon EDT Sunday for amz135. Small craft advisory from 8 pm this evening to 6 am EDT Sunday for amz137. Small craft advisory until 8 am EDT Sunday for amz150. Small craft advisory until 2 am EDT Monday for amz152-154. Small craft advisory until 6 am EDT Monday for amz156-158.
