FXUS62 KMHX 141116 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 716 AM EDT Mon Oct 14 2024 .SYNOPSIS... A cold front will cross the Carolinas this morning, ushering in much cooler weather to start the week. High pressure builds back over the Eastern seaboard midweek. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 710 AM Mon...Upper air pattern becoming increasingly meridional this AM with pronounced and anomalously deep troughing (already over a standard deviation below average over the Great Lakes) taking shape over the eastern CONUS. Embedded shortwave digging into New England is aiding in deepening and progressive low pressure over the mid-Atlantic this morning. Cold front continues to progress across the state, now along a line roughly from Winston-Salem to Charlotte. The front is forecast to cross ENC late this morning. Column ahead of the boundary will be starved of moisture outside of the mid-levels, and expect only a modest increase in cloud cover as it pushes across. Winds will be more pronounced, with gusty southwesterly flow to start the morning and continued elevated low-level thicknesses supporting a quick rise in temperatures to near 80 by midday. Once the front comes through, winds veer northwesterly but remain gusty, especially across the coastal plain. Dew points crater late today, dropping from the upper 50s this AM to the low to mid 40s by sunset. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... As of 340 AM Mon...Strong CAA behind the cold front will push temperatures sharply lower tonight under mainly clear skies as the little moisture aloft shifts offshore. There is roughly a 5 degree spread between deterministic and statistical guidance for overnight lows, and with clear skies and lighter winds nudged the forecast closer to the low end of the guidance envelope. This results in an explicit forecast of lows in the mid to upper 40s inland but 50s along the coast. Some of the more well sheltered areas are likely to decouple, and here local temperature readings could make a run into the upper 30s. && .LONG TERM /TUESDAY THROUGH SUNDAY/... As of 3 AM Mon...Strong upper level trough sweeps across the Eastern Seaboard Tue and Wed. At the same time, strong high pressure ridging gradually builds in from the west. Ridging eventually becomes centered over the Eastern Seaboard late in the week continuing to bring fair weather and dry conditions to eastern North Carolina through this weekend. Tuesday and Wednesday... Upper troughing sharpens significantly over the Eastern Seaboard on Tue and Wed as a potent shortwave rounds the base of this trough and tracks across the region before pushing offshore on Thursday. As this occurs, mid-level WSW'rly flow should bring at least some moisture over the Carolinas Tue night into Wed. Latest global, Hi-Res, and ensemble guidance has latched on to the idea that a few scattered showers or sprinkles could make their way across ENC from west to east late Tue night into Wed afternoon. Given the continued signal in forecast guidance, strength of the incoming shortwave and increased mid level moisture have elected to add in SChc PoP's into ENC between 2AM Wed and 8PM Wed with any precip chances moving across ENC from west to east. Will note precip chances may be highly dependent on if the lower atmosphere can moisten as NW'rly low level flow regimes tend to keep the area moisture starved, but given the continued signal felt confident enough to add at least a 15-20% chance of precip into the forecast. Either way even if precip doesn't develop widespread mid and low level cloud cover is forecast Tue night into Wed as the shortwave moves across the region. Much cooler temps on Tue and Wed with highs only getting into the upper 50s to mid 60s and lows getting into upper 30s/40s inland and 50s along the OBX each night. Given the forecasted temps in the 30s Wed night into Thurs this would also bring the chance at maybe seeing some patchy frost along the far western Coastal Plain. Though this will also be dependent on if winds can decouple Wed night so will need to continue to monitor the latest trends to see if the addition of patchy frost might be needed in the coming days. Thursday through the weekend...Upper troughing pushes offshore Thurs and Fri as an upper level ridge builds in from the west. At the surface high pressure becomes centered over the Eastern Seaboard by Fri keeping things dry across ENC through this weekend. Temps will gradually moderate through the weekend as well even under NE'rly flow as low level thicknesses creep up. Expect the coolest day to be Thursday with temps still in the 60s across the area but highs will quickly warm into the 70s by the weekend. && .AVIATION /11Z MONDAY THROUGH FRIDAY/... SHORT TERM /Through 06Z Tuesday/... As of 715 AM Mon...High confidence in VFR conditions through the period. VFR conditions prevail across area terminals this morning. LLWS concerns have decreased this morning as stronger axis of winds has shifted offshore, and dropped all mention from TAFs this AM. Frontal boundary itself is forecast to cross late this morning, bringing with it a surge of northeasterly winds with gusts up to 20 kt, especially across the coastal plain. Winds ease overnight and may decouple in more sheltered spots, but the new airmass will be much too dry to support any fog risk. LONG TERM /Tuesday through Friday/... As of 3 AM Mon...Primarily VFR conditions will continue through the period. Light NW'rly winds then persist through Wednesday, then shift to N'rly Thursday and Friday. && .MARINE... SHORT TERM /Through Tonight/... As of 345 AM Mon...Local observations showing marginal boating conditions over area waters this morning as southwesterly winds remain elevated ahead of an approaching cold front, currently in the lee of the Appalachians this AM. Winds are around 15-20 kt with a few gusts up to 25 kt, but this will increase into the morning as the front nears area waters. Seas range 3-6 feet, although a few 7 footers have been reported over the Gulf Stream. Southwest winds persist this AM, then veer northwesterly through the afternoon as the frontal boundary pushes across the waters. There will be a relative lull in winds during the period as the stronger surge will lag behind until sunset, when winds of 15-20 kt with higher gusts return briefly. By Tues AM, high pressure building in behind the front will help ease winds to around 10 kt out of the north, and seas will fall to around 2-4 feet. SCA headlines remain unchanged this cycle. The advisories run through late tonight, but there will be roughly a 6 hour window (around 15-21z) where winds will be more subdued at 10-15 kt. LONG TERM /Tuesday through Friday/... As of 315 AM Mon... NW'rly flow at 5-10 kts and gusts up to 15-20 kts will be possible to start the period on Tue. As we get into Tue night and Wed a sharp upper trough will track across the region and bring a surge of N'rly winds with it. This will increase winds across all the waters to 15-20 kts with gusts up to 25 kts at times Tue night into Wed. As a result this will bring our next best threat for SCA's to our waters mainly across the Pamlico Sound and coastal waters. While the winds will be increasing given the offshore flow seas will generally remain around 2-5 ft through Wed. High pressure then builds in from the west on Thurs and Fri gradually veering winds to a NE'rly direction while winds also weaken as the pressure gradient relaxes with the approach of the ridge. Seas will continue to remain around 2-5 ft though a few 6 footers may be possible along the far outer coastal waters near the Gulf Stream. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...Small Craft Advisory until 11 PM EDT this evening for AMZ131- 135-150-152-154-156-158-230-231. && $$ SYNOPSIS...MHX NEAR TERM...MS SHORT TERM...MS LONG TERM...RCF AVIATION...MS/RCF MARINE...MS/RCF