FXUS62 KILM 151412 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 1012 AM EDT Tue Oct 15 2024 .SYNOPSIS... Weak high pressure to prevail today. The next cold frontal passage expected late tonight into early Wed that may harbor a few stray showers along and after its passage. Reinforcing cold air advection in its wake will maintain below normal temps through the end of the work week. A warming trend is expected this weekend. && .UPDATE... Northerly winds and dry air advection forced a morning update to dew points. Mixing this afternoon could allow for minimum RH to drop into the mid 30% range. Otherwise, morning forecast changes were minimal. && .NEAR TERM /THROUGH TONIGHT/... Looking at mainly sunny skies today with temps having a difficult time eclipsing the 70 degree mark for highs. Normal highs are in the low to mid 70s for this time of year. Currently the area resides within an amplified mid-upper level trof attm. A rather potent mid-level s/w trof will pivot thru this upper trof, further amplifying the upper into the Gulf of Mexico. The mid-level positively tilted trof axis will lie just west of the FA late tonight, ie. at the end of this period. At the sfc, a relaxed sfc pg will reside across the FA today, with light N-NW winds expected. Tonight, that will change, a sfc trof or one could call it a secondary cold front, will push across the FA from west to east during the pre-dawn Wed hrs. After its passage, the sfc pg tightens and additional CAA will commence across the FA. The magical 1000mb-500mb 540 thickness line will be on the doorsteps of the northwestern FA by daybreak Wed. In other words, breezy NW-N winds and widespread 40+ degree temps. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... Definitely some cool season-looking charts during the short term. Moderately strong mid level trough swinging through, and it's only the southern piece of energy of the parent low just northeast of the New England States. 1000-500mb thicknesses 538-546 dam from N to S good for highs struggling to hit 60 (our lowest, mid winter highs average close to 57). Strong 40 s-1 vort swinging through to provide some healthy ascent but basically trying to squeeze blood from a stone given the very dry air below. At best this feature brings a few lingering clouds early in the day followed by a west to east transition to just about zero cloud cover. Wednesday night very chilly with widespread 30s now seemingly likely for all but the beaches. Areas with the pocosin soils in Pender and Bladen Counties could radiate just enough that future forecasts may have to debate introducing patchy frost. && .LONG TERM /FRIDAY THROUGH MONDAY/... Thursday looking pretty similar to Wednesday with respect to temperatures and less in the way of clouds with the impressive vort max moving offshore. The center of the large surface high remains to our north so we keep a light northerly wind. Friday also has a northerly component to the wind as the high noses a ridge axis into the area. As such it doesn't look like quite the temperature recovery as prev forecast. So while warmer than Thursday with highs of almost 70, temps still about a cat below climo. It is now Saturday when the bounce back to climo or above occurs even though flow stays to the NE. This is likely due to the combo of solar modification and building heights aloft. As both continue a warming trend will as well albeit only to the tune of a couple of degrees per day. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... VFR to dominate through the 12Z TAF issuance period. Dry thru the atm column this morning followed by an increase in moisture in the mid levels after 18Z, within the 10k to 15k foot level. Models a bit different with the moisture profile with the approaching mid-level trof tonight. Could observe ceilings in the 4k to 7k ft level after 06Z with a threat of isolated light showers after the passage of a sfc trof/cold front. The best threat for light pcpn, albeit low percentage, will be across LBT/FLO and possibly ILM. Winds generally N-NW around 4 to 7 kt thru this evening, then after the cfp/sfc trof passage NNW winds increase to around 10 kt few gusts to 15 kt possible as CAA settles in. Extended Outlook...Wed morning may see VFR low clouds and isolated showers but should clear out after the upper trof passage by Wed aftn. Otherwise, for the remainder of the workweek, sfc Canadian high pressure builds in. && .MARINE... Through Tonight...Winds and seas will be on a temporary diminishing/subsiding trend today. This the result of the sfc pg relaxing ahead of the next cold front/sfc trof. The current CAA will become neutral by later this morning eliminating the gustiness in the wind field. Generally looking at NW-N winds 10-15 g20 early, diminishing to 10 kt or less by this aftn and continuing into the evening. The next cold front or sfc trof is poised to reach the local waters during the pre-dawn Wed hrs from the west and should reach the offshore waters prior to daybreak Wed. The sfc pg will tighten and combined with decent CAA, SCA thresholds may be eclipsed late tonight and especially beyond this period, ie. during daylight Wed. Seas generally subsiding back to 1 to 2 ft by this aftn and evening, then building 2 to 4 ft by daybreak Wed. Given the NW-N trajectory and the coastline config, some waters directly near the beach may be flat as a pancake. Short period wind waves will dominate the seas spectrum. Wednesday through Saturday...With the recent cold frontal passage and a very large, slow moving high to our north it'll be quite some time before the area sees a wind direction other than northerly. Early on these winds will offer a few 25 kt gusts but forecast soundings show that winds don't increase with height much so am still holding off on any potential SCA. 925mb winds never seemingly get above 22kt even on the 12km WRF, which usually runs a bit hot. The offshore wind direction will keep the largest waves out to sea but the short period will make for a very bumpy ride for small craft. The late period increase in wave size will be from a building NE swell. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...None. SC...None. MARINE...None. && $$ SYNOPSIS...ILM UPDATE...21 NEAR TERM...DCH SHORT TERM...MBB LONG TERM...MBB AVIATION...DCH MARINE...DCH/MBB