FXUS62 KMHX 230548 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 148 AM EDT Wed Oct 23 2024 .SYNOPSIS... High pressure will persist over the area through mid week. A dry cold front will move through on Thursday followed by another area of high pressure late this week into this weekend. && .NEAR TERM /TONIGHT/... As of 2200 Tuesday...An upper low is residing off the Southeast coast while shortwave energy lifts into the northern Mid- Atlantic states overnight. At the surface, high pressure centered off the Mid-Atlantic coast will continue to ridge into the area while a coastal trough persists offshore near the Gulf Stream. A few showers along the coastal trough have been advecting westward toward the coast earlier this afternoon and evening and have generally been dissipating as they encounter a very dry airmass across ENC, but have seen a few relatively impressive cells move across Hatteras Island and portions of Pamlico Sound. Latest iterations of the quick refresh models are picking up on the coastal trough axis subtly shifting closer toward the coast than previously forecast. Because of this, have upped PoPs along the immediate coast to expand the area of SChc further inland and introduce higher Chc PoPs along the beaches as this pattern will likely continue through most of tonight. Have also introduced SChc thunder to grids but if any lightning does occur in low instability environment (00Z MHX sounding MUCAPE < 0.5kJ/kg) it will most likely occur offshore in cells over or just leaving the vicinity of the GStream. Otherwise expect mainly clear skies outside of occasional remnant STCU advecting inland. Good radiational cooling conditions tonight with calm winds along with higher dewpoints should allow for greater fog coverage tonight. Temps will be milder tonight with lows in the 50s inland to lower 60s along the coast. && .SHORT TERM /WEDNESDAY/... As of 445 PM Tuesday...Shortwave ridging builds across the area Wednesday ahead of a shortwave trough and attendant cold front pushes across the Midwest. Patchy fog expected to dissipate by mid day with mainly sunny to partly cloudy skies through the afternoon. Low level thicknesses increase by several meters with temps warming into the low 80s inland with mid to upper 70s along the coast. && .LONG TERM /TONIGHT THROUGH TUESDAY/... As of 200 AM Tuesday... - Near to slightly above normal temperatures expected this week - Mostly dry conditions likely through at least Friday - Monitoring fire weather conditions this week Mid-level ridging over the Southeast U.S. will get suppressed on Thursday as a shortwave drops southeast out of the Great Lakes. Guidance is in generally good agreement with this wave, although some 00z guidance has trended a bit slower with the wave. This probably doesn't have a noticeable difference on the sensible weather across ENC, though. A cold front associated with the shortwave is forecast to move quickly south across ENC late Wednesday night through early Thursday morning. A notable northerly LLJ behind the front will glance the OBX with a period of gusty winds (25-30 mph). Elsewhere, winds are expected to be a bit breezy, but not as windy as along the OBX. Mid-week temperatures are expected to peak in the pre-frontal airmass on Wednesday, potentially aided by weak downslope warming. In light of this, I went above blended guidance for highs, leaning closer to the 75th percentile of guidance. Temperatures will then trend cooler in the post-frontal airmass on Thursday (coolest along the OBX, aided by increasing onshore flow off the cooler shelf waters). Elsewhere, full sunshine should offset the weak CAA, with temps close to normal for late October. The coolest temps of the week may end up being Thursday night as high pressure builds in, setting up ideal radiational cooling conditions away from the coast. The lower end of guidance suggests some upper 30s possible in the typically colder inland locations. Return flow quickly develops on Friday and continues into Saturday. This should allow temps to rebound back above normal fairly quickly, especially by Saturday. Saturday could be another pre-frontal, downslope warming day, helping boost temps into the low 80s inland (mid-70s beaches). Yet another shortwave, and an associate cold front, are then forecast to move through Saturday night/Sunday. This should knock temps back down closer to normal on Sunday. Once again, a period of gusty northerly winds will be possible as well. Guidance differ on the magnitude of moisture advection ahead of Saturday night's front, but recent 12z/00z guidance are showing a fairly good signal for isolated to scattered showers developing along the front Saturday night into early Sunday. If this trend continues, the chance of precip will need to be increased some in later forecasts. Because of some recent run-to-run inconsistencies with the weekend front, and differences with how much moisture return occurs, we'll keep the forecast dry for now. This front may be our best shot at measurable precip over the next 7+ days. Moving into early next week, a notably strong SFC high is forecast to build into the Mid-Atlantic/New England. On the southern fringe of the high, this weekend's front may stall offshore in the vicinity of the Southeast U.S. coast. This front may eventually try to edge back north as the above-mentioned high moves offshore. If this were to happen, it could bring another chance of showers. However, the surface high forecast to move into the Northeast U.S. looks fairly stout, which may tend to keep the front, and any chance of precip, to our south early next week. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM /through Wednesday/... As of 1:30 AM Wednesday...The amount of cloud cover has exceeded most guidance given the axis of the offshore coastal low drawing closer to the coast. This greater cloud cover has dampened the fog threat, both in spatial extent and severity. Latest hi-res guidance is still showing fog developing tonight, but the timing of development has been delayed and confidence has decreased. Whether or not these mid-level clouds dissipate will determine how the fog plays out tonight. If the clouds dissipate and radiational cooling can take place, fog will be most likely at eastern TAF sites (EWN and OAJ) where moisture is greatest. Any fog that develops will dissipate a couple of hours after sunrise and VFR conditions will persist for the rest of the period with mostly clear skies and light variable winds. LONG TERM /Wednesday night through Sunday/... As of 300 AM Tuesday... - Mostly VFR conditions likely through Saturday - Gusty north winds Thursday A cold front will move through eastern NC Thursday morning, accompanied by a period of gusty north winds (highest along the Outer Banks). High pressure then builds in on Friday with much lighter winds. Modest southwesterly winds then develop on Saturday ahead of a cold front that is forecast to move through the area Saturday night. Recent guidance suggests some SHRA potential with Saturday night's front, which could also lead to a period of lower CIGs. However, at this point, the most likely scenario is predominantly VFR conditions through Saturday. && .MARINE... SHORT TERM /Through Wednesday/... As of 4 PM Tuesday...High pressure gradually weakens across the waters through the period with N to NE winds around 15 kt or less through the short term. Seas will continue around 3-4 ft. LONG TERM /Wednesday night through Friday/... As of 300 AM Tuesday... - Elevated winds and seas likely Thursday A cold front will move through area waters early Thursday morning, with a quick-hitting surge of northerly winds. During this time, winds are forecast to peak in the 15-25kt range, with higher gusts. The strongest winds are expected to be focused across the northern coastal waters and the northern rivers and sounds, where the potential exists for a few gusts of 30kt+. Prior to that front, seas of 3-4 ft will be common. Behind the front, seas are expected to build to 6-8 ft north of Cape Hatteras, with 3-6 ft seas elsewhere. In addition to the northeasterly wind swell, there will be an easterly long-period swell (10-11s) reaching the area from a deepening low pressure well offshore over the central Atlantic. Seas are expected to gradually lay down Friday and Saturday as winds lay down, and as the offshore low pulls further away from the region. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...None. && $$ SYNOPSIS...MHX NEAR TERM...CEB SHORT TERM...SK LONG TERM...RM AVIATION...RM/OJC MARINE...RM/SK