Key MESSAGE 1, Latest analysis this morning shows a reinforcing surge of cooler and drier air making its way southward across eastern NC with a 1023mb high centered over the Great Lakes ridging in from the north. The light winds and relative clear skies earlier this morning promoted patchy and shallow but dense fog in some spots, but the increasing N winds behind this front and dropping Tds are helping scour this out. Not expecting any visibility issues area-wide for the morning commute.
Tds will drop further today as high pressure builds further into tomorrow, resulting in very pleasant mild and dry days with highs near climo in the 75-80 range (low 70s OBX), but cooler than normal lows well down into the 50s for the mainland, and perhaps a few 40s for the normally cooler sheltered locales. The strongest signal for this is on Wednesday morning when the high crests overhead and environment is most favored for radiational cooling. A few spotty lows in the upper 40s are possible Thurs AM as well with light winds although TDs will be a touch higher in the morning.
KEY MESSAGE 2, Mid-level zonal flow returns Thu into the weekend, and this will bring a modest warming trend back to ENC. Sw flow returns by the weekend as low pressure over the southwestern Gulf meanders and then gradually lifts northeastward towards the MS River Valley. The evolution of this low still has plenty of question marks, especially as it interacts with the stalled frontal boundary, but a general consensus remains that as the low lifts to our west, frontal boundary will also lift northward back across the Carolinas with building WAA and deepening tropical moisture. Coupled with increasingly meridional mid-level flow, increasing rain chances are favored across much of the southeastern CONUS including eastern NC. Above-average PWATs (not a surprise for advection having Gulf origins) point to a risk of heavier rainfall with probabilities of 24-hour precipitation exceeding 1" up to 20-40% per some ensembles.
12z Tuesday through Saturday Fog has largely scoured out this morning across area terminals leaving mainly clear skies and light northeasterly winds at 5 kt or less. Outside of some spotty diurnal cu, mainly clear skies expected today with high pressure in control. Winds will become gusty with increased mixing today as gusts top out near 15-20 kt. Gusts fall off by mid-afternoon as pressure gradient eases.
Clear skies tonight with a less than 10% risk of fog - any that does develop with be very patchy and of minimal impact.
Outlook (Wednesday through Saturday): Mainly VFR conditions expected through the period, both day and night with lowered dewpoints. Overall fog chances appear low each night at around 10% or less.
Ne surge advertised over the past few days has arrived over area waters with regional observations showing winds of 5-15 kt north of Cape Hatteras, and 15-20 kt south especially for offshore waters. Seas have changed little, sitting at 3-5 feet across the region. Main change to headlines was to drop the SCA north of Cape Hatteras with winds under-performing guidance. Conditions still appear marginal with only isolated gusts to 25 kt from Hatteras south into the afternoon, save for Onslow Bay. Seas peak at around 4-6 feet by this morning, then subsiding through the rest of the day.
Outlook (Wednesday through Saturday): Northeasterly flow of 10-15 kt expected mid week as high pres will be anchored to the north, and winds/seas remain below SCA thresholds. Deteriorating conditions likely to begin on Friday and continue into the weekend as frontal boundary begins to lift back northward from the Gulf coast with increasing NE winds particularly over Onslow Bay. Sca conditions likely to re-develop over the weekend.
Nc, none. Marine, small craft advisory until 2 pm EDT this afternoon for amz154- 156. Small craft advisory until 5 pm EDT this afternoon for amz158.
