Marine Weather and Tide Forecast for Raleigh, NC

NEAR TERM /THROUGH TONIGHT/
As of 200 PM Thursday...

* Slow-moving afternoon and evening showers/storms may produce heavy downpours and localized flooding.

Regional radar and satellite imagery shows mostly clear skies over most of central NC with an area of rain and lingering low overcast across the western Piedmont of NC. On the eastern edge of the low overcast, surface dew points remain in the upper 50s to low 60s and is contributing to around 500 J/kg of MLCAPE as temperatures rise to around 80 degrees.

The main precipitation chances will be focused around the ongoing area of showers associated with a remnant convectively induced disturbance as it slowly lifts northward. Additional showers/storms will be possible across the southern Piedmont and western Sandhills this afternoon and potentially lingering in this general area into SC as long as midnight. Bottom loaded CAPE and low convective temperatures in the abnormally moist airmass has resulted in convective initiation over these areas. Main concern will be slow moving heavy downpours resulting in isolated flash flooding potential, but likely confined to urban areas. Overnight lows will settle in the low 50s in the northern Coastal Plain to around 60 elsewhere.

SHORT TERM /FRIDAY AND FRIDAY NIGHT/
As of 200 PM Thursday...

* Scattered showers/storms possible across central NC through the afternoon.

* More widespread showers/storms possible late Friday evening into the overnight hours.

Surface high pressure will slide further east into the western N.
Atlantic and promote more uniformly southerly flow across the area.
There is some uncertainty on if showers will continue into early Fri morning from prior convection upstream since it will rely on the organization of the upstream disturbance before washing out across the western NC Piedmont and southwestern VA. Low overcast and perhaps some patchy fog where overcast is lowest, will slowly lift through the morning hours.

Through the afternoon, the airmass will still be unseasonably moist with PWAT values over 1.25" and result in low convective temperatures in the upper 70s to around 80 across all of central NC.
One thing to watch will be how much afternoon mixing out of the dew points can occur as some of the more aggressive mixing models have dew points mixing into the low/mid 50s during the afternoon, which would lower available instability and raise convective temperatures.
12z HRRR supports around 500 J/kg of SBCAPE which is very marginal but certainly enough for isolated/scattered showers and storms given the favorable thermo-profiles. Severe threat still appears very limited as deep layer shear remains less than 20 kts and favor more pulse mode of convection. Afternoon highs should be similar to today (upper 70s to around 80), but dependent on overall clearing of low overcast.

Fri night into early Sat: A low-amplitude convectively enhanced shortwave is forecast to slide through the lower Ohio and TN Valley and likely bring our best chance for widespread rain and some storms, although hampered a bit by loss of diurnal heating. 12z Hi- Res guidance shows varying degrees of ongoing convection upstream that will then shift across the southern Mid-Atlantic late Fri evening through the overnight period, likely in a weakening state.
Severe potential is limited due to unfavorable diurnal timing with its passage. Overnight lows will be mild and only settle in the low/mid 60s.

LONG TERM /SATURDAY THROUGH THURSDAY
As of 330 PM Thursday...

-Showers and storms possible Saturday, then dry through Wednesday.

-Temperatures will be above-normal Saturday with a brief cool down for Sunday then return to above normal again for mid to late week.

A cold front will be moving into the Mid-Atlantic region early Saturday bringing increased rain chances through Saturday evening.
In the morning expect isolated to scattered showers and storms with a few rumbles of thunder. As the upper level trough shifts east across the region in the afternoon, an increased chance of precip is on tap for the afternoon and early evening hours. However latest model trends have been slightly lowering precip chances as the front moves across the region. Once the high-res model data begins to come in later this evening there will be a better idea of timing of the frontal passage. But for now kept PoPs in through the afternoon slowly exiting the region west to east in the evening and clearing the entire region a little after midnight. As the frontal boundary exits the region late Saturday night/early Sunday, dry surface high will slowly move into the region with cooler temperatures and refreshing dew points in the 40s Sun/Mon. The next chance of precip will be late Wednesday and again Thursday ahead of the next low pressure system moving across the MS Valley mid to late week.

Temperatures will be in the low 70s on Sunday and mid/upper 70s Monday. Wednesday is expected to be the warmest day of the 7-day forecast with upper level ridging across the region ahead of the deepening trough out west. Expect temps in the mid to upper 80s with a few warmer spots possibly hitting 90 degrees.

AVIATION /00Z FRIDAY THROUGH TUESDAY/
As of 730 PM Thursday...

Generally VFR conditions will become IFR to LIFR cigs between 06z and 09z, then linger through 13z-14z before lifting out to MVFR and VFR. Isolated showers are possible tonight, but the chance increases later tonight and Friday mainly in the Triad region.

Outlook: Scattered flight restrictions are possible through early Saturday afternoon from scattered showers and storms Friday night and a cold frontal passage Saturday. High pressure should build behind the cold front, leaving VFR conditions Sunday through Tuesday.

RAH WATCHES/WARNINGS/ADVISORIES
None.