####018007899#### FXUS62 KILM 100215 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 1015 PM EDT Thu May 9 2024 .SYNOPSIS... A typical summer time pattern will lead to daily showers and thunderstorms through Friday, sparked by a series of shortwaves moving across the area. A cold front Friday night will bring much cooler and drier air for the weekend and start of next week. Rain chances increase by the middle of next week. && .UPDATE... High clouds are clearing out quickly from west to east, with predominantly clear skies through morning. May see some low clouds during pre dawn hours, with best chance across Pee Dee region. Coastal Flood Advisory for Lower Cape Fear River in effect through 2am. Moderate risk of rip currents in effect for Brunswick county beaches, east of Ocean Isle, for Friday. && .NEAR TERM /THROUGH FRIDAY/... Atmosphere remained mostly stable today, with only a few rumbles of thunder noted earlier this morning with the first wave of convection left over from last night. Outflows dominated the stability today, while the storms that moved through parts of Georgia and South Carolina today pushed more southward than eastward. As a result, the grand majority of the activity has been limited to the CSRA and Lowcountry today. The other big theme was the cloud cover putting quite the limit on temperatures today, with only a few places reaching the lower 80s, while some only hitting the upper 70s. Subsidence it already starting to take over again late this afternoon, which will be the main idea going into tonight. Rain chances will continue to taper off this evening, with a few peeks at the stars likely late tonight. Lows in the upper 60s to near 70 at the coast. The coastal Carolinas remain well within the warm sector Friday ahead of a cold front approaching from the west. Clouds and rain chances are on the rise again. High-resolution guidance suggests potentially two waves of showers and storms: One in the midday to early afternoon, and the other in the late afternoon and evening. This seems to make sense, as the first round is associated with a shortwave that exits offshore of the Coastal Empire and moves northeastward, while the second wave is associated with the cold front itself. SPC paints the area in a "Marginal Risk" (threat level 1/5) across the area. Shear and helicity look roughly about the same as they have today, which is overall decently favorable (more so the shear). Instability may actually be more favorable, if it's realized (SBCAPE could be greater than 2000 J/kg in some spots). But we could be left with the same situation as we have been today: Can the atmosphere bust through the cap? High-resolution guidance suggests the subsidence inversion sticks around Friday, generally in the 850-700mb layer. This would seem to make sense, based on the cloud cover that is expected, which is probably at least partially the reason behind the risk only being marginal. Confidence is shaky here, but it's hard to look at what we saw today and not see a similar situation play out for Friday (i.e., less severe weather). Need to see how much convective debris will blow off of the MCS that is expected to push off Georgia and Florida Friday morning. If severe weather is realized, large hail and damaging winds would be the main threats in play once again. Highs Friday in the low-to-mid 80s. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... Cold front will be near the coast with a 5h trough lagging back to the west Fri night. The trough quickly moves through, pushing any lingering convection offshore and ushering in much drier air. Precipitable water drops under 0.50" by daybreak Sat and will stay under an inch through Sat night. There is a shortwave late Sat into Sat night that drives a secondary cold front across the area. Lack of moisture and subsidence ahead of these features will prevent any rain and even cloud cover will be limited to some flat cu at the top of the mixed layer (more likely to be altocumulus given the 8k ft mixing heights) Sat afternoon and evening. Temperatures will run several degrees below climo. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Dry, secondary cold front will be offshore Sun morning as long wave 5h trough moves east of the area. The week will start off with a very dry air mass in place and temperatures around climo. Center of the high moves overhead Sun night into Mon and then offshore Mon. Return flow develops as the high migrates east, rapidly increasing deep moisture. Precipitable water jumps about an inch in 12 hours Mon night into Tue with a warm front lifting north of the area during Tue. Rain chances increase with the front and then remain elevated Wed as a 5h trough moves across the area. The next system, moving into the region later Thu may bring another round of showers and thunderstorms in the afternoon and evening. Lows above climo Mon night and well above Tue/Wed nights. Clouds and rain will keep highs below climo Tue. A summer-like pattern returns for Wed/Thu with highs running above climo. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... VFR expected through most of the 0Z TAF period. High clouds currently over the area will continue clearing out from west to east over the next few hours. Predominantly clear skies and SW winds 5-8 kts overnight. Expect elevated surface winds to keep any fog development at bay. There is a chance, with low level moisture available and clear skies, for some low stratus to develop during pre-dawn hours. Best chance will be at KFLO - only have SCT015 in the TAFs for now as confidence is fairly low. On Friday, southwest winds around 10 kts will prevail. Expect two rounds of storms tomorrow: first in the afternoon from the WSW, and the second during the evening from the WNW as a cold front approaches. Since it's still far out and the timing needs more refining, VCTS is included in the TAFs beginning 17z. Some storms may produce gusty winds and hail. Winds will begin to turn northwesterly along I-95 in the last couple hours of TAF period as the cold front enters the area. Extended Outlook...A cold front moves through Friday night, which dries out the atmosphere. Widespread VFR should take over Friday night through Monday. Flight restrictions may occur Monday night into Tuesday with the next weather system moving in. && .MARINE... Through Friday...Southwesterly winds maintain a hold through Friday, with speeds decreasing at first tonight, and then potentially gusting up to 20kts at times Friday afternoon. Seas generally 2-4ft, with a southerly swell at 5-6 seconds. Look for a secondary easterly swell of 1ft at 10-11 seconds. Friday Night through Monday...Offshore flow develops Fri night following the passage of a cold front in the evening. Speeds around 20 kt will be possible after the passage of the front, before dropping to 10-15 kt on Sat. Winds gradually back to southerly in the afternoon, ahead of another front that will cross the waters Sun morning. Weak offshore flow redevelops behind the front then gradually becomes onshore Mon as the sea breeze drives the wind field. Seas 3-4 ft Fri night drop to 2-3 ft Sat through Mon. The wind wave will be the dominant wave with a weak easterly swell present into the start of next week. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...Coastal Flood Advisory until 2 AM EDT Friday for NCZ107. SC...None. MARINE...None. && $$ SYNOPSIS...ILM UPDATE...VAO NEAR TERM...IGB SHORT TERM...III LONG TERM...III AVIATION...VAO MARINE...III ####018004175#### FXUS61 KBTV 100215 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 1015 PM EDT Thu May 9 2024 .SYNOPSIS... Unsettled weather is expected to continue through much of the next week with chances for showers nearly every day. It'll be handy to have an umbrella or rain jacket nearby but outdoor plans shouldn't be impacted as no heavy rainfall is expected at this time. && .NEAR TERM /THROUGH SATURDAY/... As of 1015 PM EDT Thursday...Only minor adjustments made to the forecast this evening, mainly to reduce PoPs overnight as trends in guidance have been for drier conditions. Much of the lower clouds across the region earlier have eroded and we're left with broken to overcast mid and high clouds for the remainder of the night. While thick enough to block the setting sun earlier, they haven't stopped temps from cooling as previously forecasted so no changes made to overnight min temps which should mainly fall into the low/mid 40s with some isolated upper 30s in the Adirondacks and Northeast Kingdom. Another round of showers is on tap for Friday although coverage remains uncertain at this time. The upper level flow is expected to split with weak high pressure over much of the North Country which should shunt the bulk of shower activity south of the region. The latest high-res guidance is showing most shower activity will be focused across the southern Greens and Adirondack Mountains with less coverage elsewhere. Nevertheless, we don't expect a washout by any means on Friday but it might be handy to have an umbrella or rain jacket. && .SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/... As of 248 PM EDT Thursday...Scattered showers can be expected this weekend as an upper level trough swings across the region. While neither day this weekend looks to be a complete wash-out, the weather will remain fairly unsettled. The best chances for measurable precipitation will be across northern New York Saturday afternoon into the evening. Temperatures this weekend be on the cool side, with high temperatures several degrees below normal with 925mb temperatures ranging from 2C to 5C. Daytime highs this weekend will top out in the 50s to low 60s, although if the sun is able to break through clouds temperatures could warm even more under the May sun angle. Overnight lows will be more seasonable given cloud cover, with temperatures generally in the 40s. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... As of 248 PM EDT Thursday...Unsettled weather continues as we head into next week, with continued chances for showers as several shortwaves pass through the region. There continues to be some uncertainty regarding the timing and location of precipitation given the upper level pattern, with the forecast relying on blended guidance, but continued chances of scattered to numerous rain showers are expected for most of next week. The showers look to be more nuisance-type showers rather than impactful rain or thunderstorms. Temperatures next week look to be seasonable, with daytime highs in the 60s to low 70s and overnight lows in the 40s to low 50s. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... Through 00Z Saturday...VFR conditions will prevail through the period under BKN-OVC mid clouds. Some isolated showers will be possible Friday afternoon, but shouldn't reduce flight categories. Otherwise, variable winds less than 6kts tonight will continue Friday increasing to 5-10kts. Outlook... Friday Night: VFR. Slight chance SHRA. Saturday: VFR. Chance SHRA. Saturday Night: VFR. Chance SHRA. Sunday: VFR. Chance SHRA. Sunday Night: VFR. Slight chance SHRA. Monday: Mainly VFR, with local MVFR possible. Chance SHRA. Monday Night: Mainly MVFR, with local IFR possible. Chance SHRA. Tuesday: MVFR/IFR conditions possible. Chance SHRA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Clay NEAR TERM...Clay/Lahiff SHORT TERM...Kremer LONG TERM...Kremer AVIATION...Lahiff ####018006363#### FXUS62 KCHS 100215 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 1015 PM EDT Thu May 9 2024 .SYNOPSIS... A cold front will approach the area tonight, then move offshore Friday. High pressure will prevail for the weekend into early next week. A storm system could affect the area by the middle of next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Now that the higher level clouds have pulled out from earlier convection, with the wet grounds we are seeing patchy low stratus form. Some guidance indicates that there could be fog developing as well. But we're still anticipating no worse than about 2-3 miles, since geostrophic winds are just too much. So no mention in the actual forecast. Our attention turns to the west, where an MCS in Alabama and Georgia will approach overnight. But it is expected to weaken as it does so, as there are poor lapse rates, limited MUCAPE and 0-1 km bulk shear, and likely too much CINH. We do show some slight chance of showers in our Georgia zones close to daybreak however. An additional MCS in Mississippi and Louisiana, and maybe even a third from Texas would not get here until Friday. Temperatures really won't move much through the night, with actual lows in the mid 60s to lower 70s. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... The forecast for Friday is quite tricky. A quasi-zonal flow will persist aloft, though we will see several potent shortwaves ripple through the area during the day. Given the high theta-e airmass across the Southeast, ample instability should be in place to support convective development with these upper vort maxima. Furthermore, the presence of 50-60 kt of 0-6 km bulk shear will favor organization of the convection once it become established. Most of the guidance continues to indicate the most impressive shortwave will move through southeast SC/GA between 15Z and 18Z. There is surprising agreement between the synoptic models and the CAMs that a large area of showers and thunderstorms will move across the forecast area between 9am and 3pm Friday. It appears that an MCS could be ongoing across south central GA at daybreak that then pushes east through our area. Thus, the greatest coverage of convection would occur over our southeast GA zones. This is also where the strongest convective indices are expected, so our primary focus for severe weather potential is in southeast GA and extreme southern SC. Damaging winds appear to be the primary threat assuming the convection becomes organized into a line. Isolated large hail or tornadoes can never be completely ruled out. Farther to the north in SC, at least scattered showers and thunderstorms will move through, but extensive cloud cover in the morning and less available instability should reduce the overall severe weather potential. Rainfall totals on Friday will range from 1-1.5" in southeast GA and 0.5-1.0" in southeast SC. The brunt of the convection is expected to be off the coast by 3pm. A secondary shortwave will drop into SC early Friday evening, pushing the cold front into the area. A big question mark is what convection, if any, develops out ahead of the front. It will heavily depend on what happens in southern SC with the first batch of convection and whether or not the airmass gets worked-over as a result. If convective coverage is limited during the early afternoon activity, a greater degree of destabilization could occur in southern SC, allowing for a more conducive airmass for convective development late Friday afternoon or early evening. For now we penciled in scattered PoPs across eastern Berkeley/Charleston Counties late afternoon and early evening. Saturday will be dry and noticeably cooler with highs in the upper 70s. Sunday will warm up a bit due to upper ridging, with highs in the mid 80s. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Early next week will briefly start off quiet before a warm front extending across the Deep South lifts north. Conditions look quite unsettled beginning late Monday night into Wednesday due to plentiful upper forcing and deep moisture building in. Several rounds of showers and thunderstorms are expected. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... KCHS/KJZI/KSAV: VFR has returned to all sites. With at least some clearing and due to the wet grounds, some stratus and fog will develop into Friday morning. Flight restrictions are likely for several hours, at least down into the MVFR category, but potential for even IFR. An MCS will move in from the west Friday morning, impacting especially KSAV into the early or mid afternoon. For now we show just -SHRA (also VCTS at KSAV), and additional flight restrictions are possible. If there is an MCS that impacts the terminals, strong winds and heavier rains could occur. Extended Aviation Outlook: VFR conditions will return for the weekend into early next week. Scattered convection expected Monday night and Tuesday. && .MARINE... Tonight: Expect winds to be mainly S-SW 10-20 kt. A few gusts up to 25 kt are possible at times, but not enough to justify a Small Craft Advisory. Seas will be in the 2-4 ft range. Low stratus and maybe some fog will develop overnight. Likely not enough fore an advisory, but possibly a Marine Weather Statement for Charleston Harbor. Friday: A decent SW gradient expected in advance of a cold front, though winds will be quite variable once convection moves offshore midday. Late in the afternoon and early evening, wind gusts could approach 25 kt, so it's not out of the realm of possibility that a short-duration Small Craft Advisory is needed. Due to the low confidence we will hold off on any issuance with this package. Marine conditions will improve Saturday morning as high pressure builds in from the west. Winds/seas expected to increase Monday night into Tuesday ahead of the next storm system. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM... SHORT TERM...JRL LONG TERM...JRL AVIATION... MARINE... ####018006915#### FXUS62 KGSP 100217 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 1017 PM EDT Thu May 9 2024 .SYNOPSIS... A cold front will continue to push east of the area, before another system approaches Friday. Showers and thunderstorms are possible Friday afternoon, before dry high pressure builds in from the north through the weekend. && .NEAR TERM /THROUGH FRIDAY/... As of 1000 PM: The forecast is on track. Temps are falling slightly faster than expected, thanks to clear skies. But clouds will quickly spread back in from the west due to ongoing convection over MS/AL. The clouds should slow the downward temp trends. Latest guidance hasn't really trended up or down much on fog potential. So no significant changes made with the evening update. Otherwise, mostly clear skies this evening should permit good radiational cooling for a time. Some dry advection will begin overnight as weak sfc low passes by to our north, pulling very weak sfc front through the area. This will promote just enough drying to maintain a dewpoint depression of a few degrees in the foothills and upper Piedmont, and furthermore some gradient wind is expected to persist. Thus, the likelihood of radiation fog/stratus looks small in those areas and mins will remain several degrees above normal. Mountain valleys are likely to see some fog, along with the SE CWA border where that weak front doesn't reach and instead may serve to pool moisture. A couple hundred joules of CAPE may persist there thru daybreak. An MCV or other remnant of convection looks to round the base of the main trough in the morning and some guidance depicts a round of showers passing thru the Piedmont at that time. Partly cloudy skies will permit the return of warmer temps, again being a few degrees above normal. 700-500mb lapse rates will increase as main shortwave swings in, and isolated convective development is not out of the question over the mountains. For the aforementioned Piedmont areas, guidance members differ as to how soon low-level airmass change begins; GFS for example maintains poor low level lapse rates above the PBL and develops only small diurnal instability. The NAM depicts favorable lapse rates thru a deep layer and develops 1000 J/kg or more of CAPE in the afternoon. All models depict strong deep layer shear, perhaps 60+ kt, so if timing of the shortwave trends slightly slower or the low level lapse rates improve, we could see an isolated severe threat develop mainly southeast of I-85 or east of I-77. The setup warrants only a chance PoP in our south and east; FV3 and HRRR show short updraft helicity streaks from a lone cell. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... As of 1245 PM Thursday...An upper shortwave axis continues to swing east of the area Fri night as a cP air mass mixes into the lower levels. This airmass will slowly modify warmer over the weekend as a small scale ridge gives way to another diving Canadian h5 trof Sat afternoon. This trof looks to bring it/s own moisture and will probably produce some rain showers across the NC mtns Sat afternoon into the evening. No good chance of thunder during that time as sfc td/s drop into the 40s and potential instability remains nil or quite low. Drier conds with warming temps across the FA Sun as a broad sfc high builds over the area from the west. Generally, both days will be rather pleasant with highs a couple degrees below normal Sat, then back to normal levels on Sun. Mins will likely fall a couple degrees below normal each night. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... As of 120 PM Thursday...A more springtime pattern returns during the ext range. The latest guidance contines to show a subs zone becoming displaced by waves of srn stream energy while a mlvl trof/low travseres the MS to OH valleys. The surface response indicates an opening GOM flow, which will supply a good amt of moisture to a broad frontal system each day. Onset precip timing Mon is suspect with the majority of models indicating a later timeframe than the moister insitu wedge pattern progged by the latest GFS. In any case, thunder probabilty remains low with non-conducive llvl thermal profiles. By Tue, expect a better chance of afternoon thunderstorms as a wavy cold approaches from the west and sfc dewps rise into the u50s to l60s. The pattern remains uncertain, yet possibly active into Wed as another round of srn stream energy may be pushing east across the GOM coastline by then. High Temps remain near normal Mon, then drop abt 5 degrees below normal Tue with the best chance of widespread precip and cloud cover. Highs rebound to normal values Wed. Lows begin the period near climo, then warm abv normal Tue/Wed nights. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... At KCLT and elsewhere: Mainly just a few high clouds this evening, with lingering light winds out of the SW (except for NW at KAVL). Overnight, thicker mid and high clouds are expected to stream in from the SW due to convection over the central Gulf states, which combined with just enough mixing, could limit fog potential. With that said, very moist soils and low levels may combine to produce patchy fog or LIFR stratus across portions of the lower Piedmont as well as the mountain valleys sheltered from NWLY flow. Guidance is still not hitting cigs or vsby restrictions all that hard, and with the mixed signals of clouds/wind/moisture, will continue to just show few LIFR clouds and/or 6sm BR for the early morning hours Friday. If trends in the clouds and wind trend lower, potential for the stratus and fog will go up. Whatever does develop, should dissipate early Friday morning. Spotty light rain may cross the southern Upstate, but should stay mostly south of the area and looks too low for any TAF mention. In the aftn, a cold front will slip across the mountains and into the Piedmont, which may trigger a few showers and isolated TS before pushing east of the area. While better coverage of showers will be near the TN/NC border. The NC TAF sites will feature PROB30 for the SHRA potential. Given less confidence on TS, will not mention for now. The Upstate sites look largely dry Friday aftn. Winds should toggle from SW to WNW behind the front with gusts generally in the 18-22 kt range. Outlook: Drier and likely VFR conditions can be expected this weekend. Moisture returns late Monday with active weather possible by Tuesday. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...SBK NEAR TERM...ARK/Wimberley SHORT TERM...SBK LONG TERM...SBK AVIATION...ARK