303 FXUS62 KMHX 121954 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 254 PM EST Fri Jan 12 2024 .SYNOPSIS... Another strong low pressure system will then affect the region today into Saturday. Settled weather returns later in the weekend into next week, with a coastal low potentially bringing some local impacts next Tuesday into Wednesday. && .NEAR TERM /THROUGH TONIGHT/... As of 215 PM Friday... * Mesoanalysis Update * A deepening 989mb surface low is currently centered over western Kentucky, with a cold front arcing south through the TN Valley. A warm front stretches southeast to the GA coast, then northeast up the coast of the Carolinas. As of this writing, it appears the warm front is just now beginning to cross the ENC coastline, with dewpoints in the 50s, and more of a southeasterly winds, noted from the Crystal Coast to Hatteras. Meanwhile, further offshore resides an effective warm front that separates 50s dewpoints from 60s dewpoints. This boundary was analyzed to be just off the SC coastline. North of the synoptic warm front, widespread showers and scattered thunderstorms are ongoing from the Ohio Valley south through the Gulf Coast States. Closer to home here in ENC, clouds are increasing thanks to increasing southerly moisture advection. Through tonight, the overall spirit of the forecast hasn't changed significantly. However, below are a few thoughts on what has been observed upstream, and what impact this may have locally. The strongest large-scale forcing for ascent is still forecast to be removed from ENC, with lift focused along mesoscale boundaries and a broad area of WAA. The thinking, then, is that the above-mentioned synoptic warm front will lift north through the Carolinas this evening with an increased risk of WAA-driven showers. Through the night, very strong moisture transport on the nose of a 50-70kt southerly LLJ will lead to rapid moistening aloft. This will occur beneath modest mid-level lapse rates, supporting a layer of elevated instability developing above a more stable boundary layer. As instability builds, the risk of isolated to scattered thunderstorms will gradually increase as well. Despite increasing low-level moisture advection, the general expectation is that we will struggle to realize sufficient SFC-based instability. Based on all of this, I expect any convection tonight to tend to be elevated in nature, with a lower risk of SFC-based convection. Because of the strong flow aloft, shear in the effective inflow layer is forecast to be 40- 50kt, which will be more than sufficient for organized convection. However, the lack of stronger lift will tend to keep the risk of deep convection low, and probably focused offshore. All of this should keep the risk of severe weather on the marginal side. SPC recently adjusted the DY1 outlook to MRGL for the Carolinas, and given recent trends in obs and model guidance, this seems very reasonable. For updated hazard potential through tonight, please see the breakout below. Impacts from this system expected across eastern NC: Gale Force winds across the waters from late today into Sat. (Please see the Marine discussion below for further details). Strong gradient winds, especially along the coast where a Wind Advisory is in effect tonight for gusts of 45-50 mph. The potential for strong to marginally severe thunderstorms this evening with strong wind gusts and possibly some hail. Only minor coastal flooding is anticipated with this system as the duration and magnitude of the strongest winds will be less than the front that affected the area Tue/Tue night. (Please see the Coastal Flood Discussion below). && .SHORT TERM /SATURDAY/... As of 245 PM Friday... A drying, post-frontal airmass will settle in on Saturday. CAA will support deepening mixing, tapping into residually strong winds aloft, leading to gusty WSW winds continuing, especially in the morning. Temperatures on Saturday will be cooler than today, but not drastically so. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... As of 345 AM Fri... Saturday through Sunday...Upper low aloft over the Great Lakes will lift over eastern Canada over the weekend, with the cold front pushing any lingering showers offshore first thing Sat AM, and CAA prevailing Saturday ahead of mild high pressure that moves overhead Sunday. Mainly dry conditions with temps near normal. Monday through Friday...Broad troughing prevails over the central and eastern US through much of next week with a strong shortwave moving over the area later Tuesday into Wednesday being the feature of note. At the surface, high pressure ridging just north of the area keeps settled weather in place on Monday, before low pressure developing along the Southeast coast potentially impacts the area Tuesday into Wednesday. Significant variability in timing and location of this low make the forecast uncertain, but a general track off the coast, with likely PoPs for OBX and chance POPs elsewhere, greatest near the coast, continues to be the best forecast. Some guidance is showing the potential for some wintry mix to develop as the rainfall is pulling away from the area and CAA is beginning early Wednesday morning, but guidance tends to overdue the longevity of the precip for these type of events, and it is unlikely based on the latest guidance that any precip will linger long enough to get any change over to flurries. Behind the coastal low we will have very cold, dry air moving in, with dewpoints approaching the single digits and low temps approaching 20 inland Tuesday night. This CAA could result in fire weather concerns and apparent temperatures in the single digits. High pressure builds back in late in the week with dry weather and mild temps expected Thursday and Friday. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... SHORT TERM /Through 18z Saturday/... As of 1230 PM Friday... KEY MESSAGES 1) Deteriorating aviation conditions this evening/tonight FORECAST DETAILS High pressure continues to shift away from the area this afternoon, as yet another strong weather system approaches from the west. That system will send a cold front east through Eastern NC tonight, and will be accompanied by an increased risk of sub-MVFR conditions, SHRA, TSRA, and gusty winds. Winds near and just ahead of the front will reach as high as 30-40kt out of the S or SE. Behind the front, a wind shift will lead to gusty WSW winds of 25-30kt. Where TSRA occur, there will be a risk of hail and enhanced wind gusts. CIGs should gradually improve back to VFR during the day on Saturday. LONG TERM /Saturday night through Wednesday/... As of 330 AM Fri...VFR returns for the remainder of the weekend into Monday. A coast low will bring the next chance for widespread flight restrictions and gusty conditions Tuesday into Wednesday. && .MARINE... SHORT TERM /Through Saturday/... As of 245 PM Friday... **Hazardous marine conditions late tonight into Saturday** East/southeast winds are finally beginning to increase across area waters, but it has been a slower increase than originally forecast. Despite the slower onset, the peak magnitude of winds later this evening through tonight still looks good, so no significant changes were made regarding winds. A period of gales is still expected for all waters prior to the passage of a cold front later tonight. With the cold front will come an increased risk of showers and thunderstorms, some of which could produce hail, enhanced wind gusts, and waterspouts. Behind the front, gusty WSW winds will linger into Saturday. Seas will build to 8-12ft ahead of the front tonight, then gradually fall to 5-8 ft by Saturday afternoon. && LONG TERM /Saturday night through Wednesday/... As of 330 AM Fri...High pressure builds in behind this departing low, with conditions gradually improving and likely falling below SCA criteria by Sunday. Tuesday into Wednesday models are depicting a coastal low trekking up the coast, bringing at least SCA conditions for coastal waters, with a bit more uncertainty for the inland sounds/rivers. .HYDROLOGY... As of 250 PM Friday...Rivers will eventually respond to the widespread rain from Tue/Tue night with river forecast center guidance suggesting these rises into minor flood stages will hold off until Saturday or Sunday as water upstream slowly works towards the coast. At this time, widespread river flooding is not anticipated. && .TIDES/COASTAL FLOODING... As of 345 AM Fri...Gusty southwest winds develop Friday evening but will be brief. Given the flow regime and only marginal gales, coastal flooding should be very minor, with inundation values across the northern shores of the Pamlico Sound mainly around one foot or less. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...Wind Advisory from 7 PM this evening to 5 AM EST Saturday for NCZ047-081-195-196-203>205. MARINE...Gale Warning from 7 PM this evening to 3 AM EST Saturday for AMZ131-135>137-150-152-230-231. Gale Warning until noon EST Saturday for AMZ154-156-158. && $$ SYNOPSIS...MHX NEAR TERM...RM/JME SHORT TERM...RM LONG TERM...CB/RJ AVIATION...RM/RJ MARINE...RM/RJ HYDROLOGY...MHX TIDES/COASTAL FLOODING...MHX