####018008638#### FXUS61 KCLE 031955 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 355 PM EDT Fri May 3 2024 .SYNOPSIS... An active pattern continues as a cold front moves east across the area tonight. Another warm front will lift north on Saturday followed by a cold front on Sunday as the parent low moves northeast into Quebec. High pressure will push in briefly Monday. && .NEAR TERM /THROUGH SATURDAY NIGHT/... An active weather pattern will continue through the near term period as multiple boundaries enhanced by upper level shortwaves move across the area. Setting up the big picture, there is a broad upper level trough across the northern contiguous US with an associated low pressure at the surface centered over the north-central US. A cold front associated with this system will move east across the area tonight, bringing another chance of precipitation. Much of the support for shower development is coming from upper level embedded shortwaves which are advecting vorticity across the area. This support coupled with an area of low level convergence should allow for more widespread showers to become established along and east of I71 this evening into the overnight hours. Overall mesoscale conditions, including instability and shear, remain very minimal this afternoon so getting any thunder may be hard but cannot rule out a few rumbles. Primary concern would be heavy rainfall in the strongest showers which may result in nuisance flooding. By Saturday morning, a nose of high pressure pushes over the area and allows for a very brief, although cloudy, period of no precipitation. By Saturday afternoon, another warm front will move north across the area, allowing the chance of showers and isolated thunderstorms to return. These should gradually begin to taper from west to east early Sunday as another cold front approaches, but maintained slight chance for this period. Highs tomorrow will reach into the 70s across western counties, but will remain in the 60s for far NE OH and NW PA. Overnight lows both nights will be in the upper 50s to low 60s. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... A cold front will likely be approaching Toledo early Sunday and will slowly cross the area from west to east by Sunday evening. A slug of deeper moisture and associated showers may still be impacting far eastern OH into northwestern PA early Sunday, though farther west should start the day fairly dry. Additional showers & thunder are expected to develop along the cold front by late morning or early afternoon is it drifts east out of northwestern Ohio and into north central Ohio and then continue east through the afternoon and early evening. Overall, Sunday will feature more clouds than sun with showers and thunder around at times, though a washout type steady rain is unlikely. Not seeing much of a severe weather threat on Sunday, as forcing and shear will be weak. Thermodynamics may support a few stronger storms east/southeast of a Mount Gilead - Parma - Chardon - Edinboro line during the later afternoon hours, with small to perhaps near-severe hail and locally strong winds the main concern if any storms briefly pulse stronger before collapsing due to the lack of stronger shear. Storm motion won't be all that fast so can't rule out a gully-washer or two, though am not expecting enough organization for much of a flooding threat either. High pressure briefly noses in from the north Sunday night into Monday behind the cold front, which should allow us to dry out. As the front begins returning as a warm front late Monday into Monday night rain chances may begin returning from the southwest. Gut feeling is that Monday and Monday night may end up drier than currently forecasted, though given enough model spread and a need to be collaborated, only made modest reductions to the NBM POPs. Highs on Sunday will hinge on how long we can break into some sunshine behind showers exiting to the east in the morning and activity developing and spreading across the area along the cold front during the midday and afternoon timeframe. For now, generally have most of the area in the 70s. Highs generally range from the mid 60s along the lake to the low to mid 70s well-inland on Monday. Lows Sunday and Monday nights will generally settle into the 50s. && .LONG TERM /TUESDAY THROUGH FRIDAY/... The long term will begin with a trough over the northern Plains and a ridge centered over the Southeast, with broad southwest flow in between. The trough will begin shifting towards the Midwest and Great Lakes by Friday. A warm front is expected to lift through on Tuesday, with a cold front expected to cross Thursday into Friday. There will be relatively higher chances for showers and thunder both with the warm frontal passage Tuesday into Tuesday evening, and again Thursday into Friday as the cold approaches and crosses. While we'll be in the open warm sector on Wednesday, activity may develop upstream and spread in later in the day or at night. Severe weather and flooding potential are uncertain, as we will be on the fringes of a moist and unstable with enough flow aloft for organized convection. However, many solutions develop organized clusters of convection well upstream across the Mississippi and Ohio Valleys most days, which would tend to track just to our south and also act to overturn the greater instability before it can advect in. We are not currently "outlooked" for severe weather by the SPC which seems reasonable given the uncertainty and potential limiting factors mentioned above, though experimental machine learning severe weather guidance from Colorado State University does suggest severe potential may bleed into our area (with greater risk just to our southwest) if upstream convection is not too expansive. Temperatures will lean warmer than normal until the cold front crosses. && .AVIATION /18Z Friday THROUGH Wednesday/... Widespread VFR conditions will continue ahead of the approaching cold front through the first part of tonight. There is currently an area of light rain showers moving east across the area, but no thunder has been reported and visibilities have remained near 10SM. There remains a potential of scattered thunderstorms late this afternoon into the evening hours as an upper level shortwave enhancing lift over the area. With low confidence in the placement of these thunderstorms, opted to handle them with a TEMPO beginning at 21Z for KTOL and gradually push east. In the strongest storms, visibilities and ceilings may briefly fall to MVFR conditions, but should quickly rebound. Overnight tonight, the aforementioned pushes east, allow for much of the area to briefly experience dry conditions. Behind this boundary, ceilings will lower to MVFR heights and should persist for most sites through the end of the period. A chance of showers returns Saturday afternoon. Variable winds of 4-6 knots will persist across the area until Saturday morning when they become sustained at 5-10 knots from the southeast. The exception will be KTOL which will have a 5-10 knots wind from the northeast. Isolated gusts are possible near the end of the period for KERI due to downslope enhancement. Outlook...Non-VFR likely with periodic showers and thunderstorms through Tuesday. && .MARINE... No marine headlines are expected for the foreseeable future. Southeast winds may briefly become gusty in the nearshore waters off of Pennsylvania late Saturday night into early Sunday morning, though sustained winds likely remain below Small Craft Advisory criteria. A cold front will cross on Sunday. A warm front lifts across the lake Tuesday into Tuesday night, followed by a cold front next Thursday or Friday. A few thunderstorms are possible over the lake Saturday afternoon through Sunday afternoon ahead of an approaching cold front, though greater potential will likely be inland. Additional thunderstorms are possible at times over the lake Tuesday through Friday next week. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. NY...None. MARINE...None. && $$ SYNOPSIS...Campbell NEAR TERM...Campbell SHORT TERM...Sullivan LONG TERM...Sullivan AVIATION...Campbell MARINE...Sullivan ####018009204#### FXUS61 KOKX 031956 AFDOKX Area Forecast Discussion National Weather Service New York NY 356 PM EDT Fri May 3 2024 .SYNOPSIS... High pressure along the New England coast and into our area will remain nearly stationary into Saturday. A cold front then slowly approaches from the west on Sunday and moves across the area Sunday night into Monday. The boundary likely stalls to our south Monday afternoon through Tuesday before returning as a warm front Wednesday. A series of frontal waves may impact the area to end the week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... A high amplitude upper ridge over the eastern third of the country will be slow to translate east through the first half this weekend. This will keep surface high pressure ridging down along the New England coast and into our area. Expect a light easterly flow to continue with varying amounts of cloud cover. Satellite imagery shows a fair amount of high clouds moving through the upper ridge axis. This could impact temperatures somewhat depending on the opacity. Lows will generally be in the mid to upper 40s, but around 50 for the NYC metro. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/... Not much change during this time as the forecast area will remain under an easterly flow at 10 mph or less. Varying amounts of high clouds will filter through the upper ridge over the area on Saturday, which works to the east Saturday night. Clouds will lower and thicken Saturday night with some fog possible toward daybreak Sunday. Warm advection rain on the backside of the ridge, ahead of an approaching warm front, continues to trend slower. Chances of rain Saturday night remain low and mainly after midnight. Temperatures during this time will at or just below normal. && .LONG TERM /SUNDAY THROUGH FRIDAY/... *Key Points* *An approaching front will bring rain Sunday into Sunday night, which ends early Monday morning. Rainfall amounts average one quarter to one half inch. *The front stalls to our south early next week with limited chances for showers through Tuesday. *Unsettled conditions are likely Wednesday through next Friday, although not a wash out. Several frontal waves are possible, which may bring periods of showers, but timing is uncertain. *Below normal temperatures Sunday should trend back above normal next week. Timing of the potential precip could impact temperatures late in the week. A shortwave associated with a larger upper low over Central Canada will try to break down the highly amplified ridging over the east coast to start the long term. The guidance has continued to show a slower trend to this process with the associated frontal system not moving through the area until Sunday night or early Monday. Rain associated with the front should start in the morning west of the NYC metro and then slowly spread eastward through the afternoon. This continues to look like mainly an overrunning rainfall with little to no elevated instability. Average amounts range from around one quarter to one half inch. The shortwave axis will push offshore later Monday with the front stalled to our south and west. Another highly amplified ridge builds across the Great Lakes in response to a large upper low over the Northern Plains and Northern Rockies. There are conflicting signals in the guidance for whether or not energy will traverse underneath the ridge towards the area Monday night. This potential energy would interact with the stalled front to bring another chance of rain. However, some of the global guidance weakens the energy with the height field becoming suppressed over New England in response to an upper low over the Maritimes. A weak high pressure should build towards New England which should keep any precip, if it were to develop, mainly near the coast closer to the stalled front. Have used the NBM for PoPs with just a low chance near the coast Monday night. A piece of the ridge builds overhead on Tuesday, so this should end up being a mainly dry day. The next forecast challenge will be for Wednesday through the end of the week. The stationary front to our south and west should begin lifting back north as a warm front on Wednesday. The parent low will be associated with the upper low over the Northern Rockies and Northern Plains, but there may be a few waves along the warm front. One of these may be enough to initiate some convection Wednesday afternoon or evening. The upper low then slowly moves east towards the Great Lakes to end the week. Several frontal waves may move across or just south the area keeping conditions unsettled. Timing of these waves is highly uncertain given a late Day 5 through Day 7 forecast, so have capped PoPs off at high chance for now. Sunday will be cool with rain and temperatures in the middle to upper 50s. Conditions should begin rising back above normal next week with temperatures in the 70s most afternoons away from the immediate coastline. Have followed the NBM deterministic, but it should be noted that there is a fair amount of spread in the guidance, especially later in the week due to the potential precip. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... High pressure remains along the New England coast and into our area through Saturday. VFR to start. Cigs may fall once again into late tonight into Saturday morning with potential stratus development, though confidence is too low to prevail at this time. However, added a TEMPO group for this possibility from 08Z-12Z Saturday. An E/SE flow with speeds around 10 kt or less will shift to the E tonight for the city terminals, and become light and variable for the outlying terminals. An occasional gust to around 20 kt is possible into the early evening hours. SE winds on Saturday with speeds at or below 10 kt. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... There is uncertainty with the development of MVFR or lower clouds tonight. Best timing for this is between 08Z-12Z. OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY... Saturday: Mainly VFR. Low prob of patchy early AM MVFR stratus. Slight chance of showers and MVFR conditions in the afternoon, increasing chances overnight. Sunday...Likely showers, with MVFR or lower conditions. ESE winds G15-20kt. Monday...VFR. Tuesday... Mainly VFR. Chance of MVFR showers. Wednesday...MVFR or lower with a chance of showers. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Sub-SCA conditions are forecast to start the weekend with high pressure along the New England coast maintaining an easterly flow across the waters. Winds will generally be around 10 kt. Winds and seas should remain below SCA criteria Sunday the middle of next week with a weak pressure gradient in place. There may be an increase in winds closer to 20 kt and seas building to around 4 ft, but conditions are expected to remain below SCA levels. && .HYDROLOGY... There are currently no hydrologic concerns through next week. &&Weak high pressure builds in through the day, then retreats to the Canadian Maritimes Saturday. Continued improvement in cigs expected through the afternoon with VFR expected by 19Z for most, if not all terminals. Cigs may fall once again into late tonight into Saturday morning with potential stratus development, though confidence is too low to prevail at this time. However, added a TEMPO group for this possibility from 08Z-12Z Saturday. An E/SE flow with speeds around 10 kt or less much of the day will shift to the E tonight for the city terminals, and become light and variable for the outlying terminals. An occasional gust to around 20 kt is possible this afternoon into the early evening hours. SE on Saturday with speeds at or below 10 kt. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... There is uncertainty with the development of MVFR or lower clouds tonight. Best timing for this is between 08Z-12Z. OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY... Saturday: Mainly VFR. Low prob of patchy early AM MVFR stratus. Slight chance of showers and MVFR conditions in the afternoon, increasing chances overnight. Sunday...Likely showers, with MVFR or lower conditions. ESE winds G15-20kt. Monday...VFR. Tuesday... Mainly VFR. Chance of MVFR showers. Wednesday...MVFR or lower with a chance of showers. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...DS/DW NEAR TERM...DW SHORT TERM...DW LONG TERM...DS AVIATION...JP MARINE...DS/DW HYDROLOGY...DS/DW ####018004669#### FXUS64 KOUN 031958 AFDOUN Area Forecast Discussion National Weather Service Norman OK 258 PM CDT Fri May 3 2024 ...New SHORT TERM, LONG TERM... .SHORT TERM... (This evening through Sunday) Issued at 258 PM CDT Fri May 3 2024 Scattered strong to severe thunderstorms are expected to develop across the Texas South Plains later this afternoon. The remnants of this activity--especially any left splits--may affect western north Texas this evening before dissipating. However, with the trend of initiation farther to the southwest, it appears the chance of severe weather will be spatiotemporally limited. Large hail and damaging wind gusts will be the primary hazard. Additional thunderstorms are expected to develop across Kansas and consolidate into a complex with the remnants moving into northern Oklahoma late tonight into Saturday morning. These thunderstorms will have a threat for damaging wind gusts and heavy rainfall, which should weaken with southward extent. By Saturday afternoon, additional thunderstorms may develop during the afternoon hours along the boundary from the morning thunderstorms across Oklahoma. In addition, a complex of thunderstorms will likely develop across the Texas panhandle and western north Texas that will move eastward across at least the southern half of the area during the overnight hours. Large hail, damaging wind gusts, and flooding will be the potential hazards with the primary hazard becoming flooding. Given the recent heavy rainfall, we issued a Flood Watch from 7 PM tonight through 1 PM Sunday for all locations except northwest into west central Oklahoma (where rainfall amounts have been lighter the last week). Additional heavy rainfall will result in a risk of flooding through Sunday morning. Mahale && .LONG TERM... (Sunday through next Thursday) Issued at 258 PM CDT Fri May 3 2024 Monday: There is the potential for a significant severe weather event Monday afternoon and evening. A negatively tilted trough will eject into the Plains on Monday with a moist, highly sheared, and unstable air mass ahead of a dryline. The synoptic-scale pattern is a classic severe weather outbreak across the Plains with a threat for large hail, damaging wind gusts, and tornadoes. While there is some variation on the mesoscale details among deterministic models and ensemble members (e.g., character of the mid/upper level trough, location of the dryline, and the magnitude of capping) that will affect the location and magnitude the severe weather risk, it is important to stay weather aware on Monday as the worst case scenario (i.e., How bad could it be?) for the event is quite high with the potential for significant supercells. Tuesday: As the mid-level trough lifts to the northeast, the trailing dryline may stall across east central into southeast Oklahoma. While the dryline will be somewhat diffuse, there is a low chance thunderstorms may develop during the afternoon with a modest mid-level flow persisting across the Southern Plains. Wednesday: Additional severe thunderstorms will be possible Wednesday afternoon, especially across southeast Oklahoma with the dryline still in place. Thursday: There may finally be a lull in the risk for severe weather with a cold front moving through the area with a drier air mass advecting southward into the area. Mahale && .AVIATION... (18Z TAFS) Issued at 1223 PM CDT Fri May 3 2024 Low stratus will continue to affect most TAF sites through the afternoon, and will affect all TAF sites later in the period. There is a low chance that storms move into portions of western Oklahoma and northern Oklahoma overnight. Southeasterly winds will shift towards the north as a cold front moves in early Saturday morning. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 63 76 60 72 / 30 70 80 80 Hobart OK 59 74 57 74 / 40 70 90 60 Wichita Falls TX 63 79 62 76 / 30 50 90 60 Gage OK 52 69 51 75 / 80 50 60 40 Ponca City OK 61 73 56 71 / 60 70 60 70 Durant OK 64 79 64 77 / 20 40 70 80 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...Flood Watch from 7 PM CDT this evening through Sunday afternoon for OKZ006>008-011>013-018>020-023>048-050>052. TX...Flood Watch from 7 PM CDT this evening through Sunday afternoon for TXZ083>090. && $$ SHORT TERM...10 LONG TERM....10 AVIATION...13 ####018007841#### FXUS64 KFWD 031958 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 258 PM CDT Fri May 3 2024 ...New Long Term... .SHORT TERM... /Issued 214 PM CDT Fri May 3 2024/ /Through Tomorrow Afternoon/ A Flood Watch is now in effect for eastern Central Texas and the Brazos Valley. This watch will continue through Sunday morning as multiple rounds of heavy rainfall are expected. The weather across North and Central Texas will remain fairly active as a warm and humid airmass remains established atop our region. As you step outdoors, the humid airmass remains evident with dew point temperatures in the upper 60s to lower 70s. Early morning convection across southern Oklahoma sent an outflow boundary southward, meanwhile, ongoing storms across Central Texas continue to push northwestward. These outflow boundaries will likely be the focus for isolated convection across North Texas this afternoon. Given a lack of strong flow, any convection is likely to remain highly disorganized and fairly short-lived. Nonetheless, lighting and gusty winds will remain possible with any of the storms this afternoon. Across eastern Central Texas, another remnant boundary continues to be the focus for occasional bouts of heavy rain through the rest of this afternoon. Considering the antecedent conditions, a quick 1-2 inches of rain can lead to flash flooding. Storm chances should dissipate around or shortly after sunset as daytime heating comes to an end. This is when we'll turn our attention to the dryline across West Texas, where storms are once again expected. Although the dryline will likely be about 100 miles west of our region, storm motion this evening will be to the east with a few storms arriving to our western-most counties by 9-10pm. Given the storms will become increasingly displaced from the source of lift, expect storms to gradually dissipate trough the night. There is a low (~20%) chance of showers or storms approaching the I-35 corridor closer to midnight. Storms would be decaying, thus, the threat for severe storms would remain low. Tonight, expect cloudy and above normal temperatures will lows remaining in the mid to upper 60s areawide. Our next rain chances will arrive tomorrow as a cold front moves southward across our region. A shortwave trough will be migrating eastward, likely firing off thunderstorms along the leading edge of the front. At this time, the greatest rain chances will likely be beyond sunset tomorrow, however, a few isolated showers and storms cannot be ruled out between noon and sunset. Any storms that do develop in the afternoon could contain small hail and gusty winds. High temperatures tomorrow will be in the upper 70s to lower 80s with southerly winds continuing. Hernandez && .LONG TERM... /NEW/ /Saturday Night Onward/ An active weather pattern will continue Saturday night as a shortwave embedded in the subtropical jet lifts northeast across North and Central Texas. Thunderstorms will likely be ongoing at the start of the period across the Big Country, and will spread east across the region overnight into Sunday morning. A wind and hail threat may accompany these storms across the western half of the region Saturday evening, but convection will be weakening Saturday night while moving into a less favorable environment. Despite the severity or lack thereof, the presence of a quasi- stationary surface boundary will maintain a threat for more heavy rain and flooding. This threat will be highest over Central Texas where heavy rains have already occurred, and where the front will most likely be located (and is currently exacerbating the ongoing flooding across the Brazos Valley and Southeast Texas). A Flood Watch has hence been issued through around midday Sunday for those Central Texas Counties who have experienced multiple rounds of heavy rain over the past several days. Convection will move out during the morning hours Sunday, making for an overall decent day with highs mainly in the 70s. There may be a few rogue showers that pop up in the afternoon but those should be few and far between. Attention will then turn to a larger scale upstream trough, which will cross the Rockies Sunday night, then lift northeast through the Plains on Monday. Most of the ascent associated with this system will remain to our north, but we will still likely have isolated dryline-induced convection Monday afternoon and evening. Coverage may be low due to the presence of a capping inversion, but we will otherwise have a warm and unstable environment in place, and any storms which develop could become severe. The passing of the shortwave will send a cold front south into the area Tuesday night. After a quiet Tuesday, the front will again provide a focus for convection starting Wednesday, as a longwave trough produces cyclonic flow overhead for the mid to late week period. Scattered showers and storms should develop in the afternoon and evening hours Wednesday and Thursday. Not all will receive rain, but just about any of the area could see a shower or storm. By Friday, the front will have sagged well south of the I-20 corridor, unfortunately focusing convection across the saturated Central and Southeast Texas. The front and trough will both shift southeast of the region on Saturday, providing dry weather and overall nice conditions in time for Mother's Day weekend. 30 && .AVIATION... /Issued 108 PM CDT Fri May 3 2024/ /18Z TAFs/ Concerns...Low storm potential this afternoon. MVFR/IFR expected once again tonight through tomorrow. With the unsettled weather pattern continuing atop North and Central Texas, there will be a renewed chance of isolated storms within the D10 airspace this afternoon. Coverage will remain minimal, but some impacts to aviation traffic will be possible. Any storms that do develop will dissipate after sunset as south winds persist. The dryline, which will be across West Texas and the Texas Panhandle, will once again fire off thunderstorms this afternoon. Storms are expected to remain west of the D10 airspace, however, any westward traffic may see impacts due to the afternoon and evening convection. Ceilings will be deteriorating overnight, with MVFR around midnight, then IFR closer to 08Z. This trend is fairly similar across Waco where a similar airmass will be in place. The sub-VFR ceilings are expected to linger through tomorrow morning before improvements begin in the afternoon. Storm potential tomorrow afternoon remains too uncertain to mention in the TAF. There is higher confidence in tomorrow night's convection, however, that is beyond this forecast cycle. Hernandez && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 68 80 66 78 68 / 20 20 90 50 20 Waco 68 80 67 78 67 / 20 40 80 40 20 Paris 64 79 65 75 65 / 20 40 80 60 20 Denton 66 79 64 77 66 / 20 20 80 50 20 McKinney 66 79 65 77 67 / 20 20 90 50 20 Dallas 68 80 67 79 68 / 20 20 90 50 20 Terrell 66 80 65 76 67 / 20 30 90 50 20 Corsicana 68 82 67 77 69 / 20 40 80 50 20 Temple 68 81 66 79 68 / 20 40 80 40 20 Mineral Wells 66 80 63 76 67 / 30 30 80 30 20 && .FWD WATCHES/WARNINGS/ADVISORIES... Flood Watch through Sunday afternoon for TXZ135-146>148-160>162- 174-175. && $$ ####018003713#### FXUS61 KCAR 031958 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 358 PM EDT Fri May 3 2024 .SYNOPSIS... High pressure will cross the region tonight through Saturday, then exit across the Maritimes Sunday. An occluded front will cross the region Sunday night into Monday. High pressure will cross the region Tuesday. Low pressure will approach Wednesday. && .NEAR TERM /THROUGH SATURDAY/... High pressure, surface/aloft, will remain ridged across the region tonight through Saturday. Moisture beneath the subsidence inversion, along with clouds wrapping back across the region from the Maritimes, will keep partly/mostly cloudy skies across the forecast area tonight. Diurnal cloud development and clouds wrapping back from the Maritimes will keep partly sunny/mostly cloudy skies across the region Saturday. Low temperatures tonight will range from the upper 30s to around 40 across the forecast area. High temperatures Saturday will range from the upper 50s to around 60 across much of the forecast area. However, mid to upper 50s will occur along the Downeast coast where onshore winds will develop. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/... Surface high pressure should remain centered over NB Saturday night. Upper air model soundings indicate a moisture low layer throughout the night, thus cloudy skies are expected. Temps should be fairly mild with S flow and light winds. By Sunday, a weakening occluded frontal boundary starts to approach from the west. Clouds and S winds should increase into the afternoon with the tightening pressure gradients. By the evening, the chance for rain showers should spread to the eastern border. By Sunday night, rain showers will continue with decreasing S winds. QPF models show the majority of rain staying to the south as the low intensifies. By Monday, the system will pick up speed and pull the rest of the rain showers out of the region. The 925mb model temps show a warm airmass behind the system, which should bring temps above normal for the day. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... High pressure returns to the region Monday night and remains in the area through Tuesday night. By Wednesday, the extended models are picking up on some shortwave energy moving across the waters. However, the 12z model runs showing the rain staying far to the south. The NBM had to much precip in the forecast for the end of the week due to these shortwave systems, so decreased precip to chance or slight chance. The models lose consistency by the weekend. Temps should be near normal. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... NEAR TERM: VFR early tonight. VFR/MVFR ceilings then expected later tonight through early Saturday. Otherwise, expect VFR conditions Saturday. Light and variable winds tonight. Variable winds 5 to 10 knots Saturday. SHORT TERM: Sun night...all TAF sites low MVFR of IFR clgs with ocnl shwrs. Lgt Winds. Mon...all TAF sites VFR clgs. Brief MVFR vsbys possible in Aftn shwrs msly Nrn TAF sites. Lgt to mdt SW winds becmg NW late in the day. Mon night-Wed...all TAF sites VFR - low VFR clgs. Lgt to mdt NW winds. && .MARINE... NEAR TERM: Winds/seas below small craft advisory levels tonight through Saturday. SHORT TERM: Winds and seas should remain below SCA conditions through this period. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ Near Term...Norcross Short Term...LaFlash Long Term...LaFlash Aviation...Norcross/LaFlash Marine...Norcross/LaFlash ####018009685#### FXUS62 KRAH 031959 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 359 PM EDT Fri May 3 2024 .SYNOPSIS... Sub-tropical high pressure will extend across the South Atlantic states today, while a backdoor cold front will move through eastern VA and northeastern NC. The front will settle southwestward and into north-central NC tonight, where it will stall through Saturday night, then weaken and move northward into VA on Sunday. && .NEAR TERM /THROUGH TONIGHT/... As of 355 PM Friday... Convection has indeed developed along the differential heating zone described below, while a few isolated cells have otherwise developed in areas of towering cumulus within a lee surface trough over the Piedmont (in and around the Triad and more recently over swrn Wake Co.). Some merging of outflows and additional, pulse/multi-cell development will remain possible with the upstream/differential heating-forced convection into the srn and wrn NC Piedmont through this evening. TCLT has measured 30-40 kt velocity from downdrafts with these cells around SVH and AKH in the past hour. Similarly strong gusts will be possible with these and other more-isolated ones over the Piedmont, where SPC Meso-Analysis data indicates 1000- 1200 J/kg of DCAPE has developed this afternoon. .PREV DISCUSSION... /ISSUED 1145 AM EDT Fri May 03 2024/ A mid/upr-level ridge centered near the srn Middle Atlantic coast will remain so through tonight, while a mid-level trough and embedded, weak MCVs now over the ern OH and TN Valleys will be directed around the ridge and into the cntl Appalachians. At the surface, a 1019-1020 mb sub-tropical high will remain situated off the coast of the Carolinas. Meanwhile, a backdoor cold front, now stretching from the mouth of the Chesapeake Bay nwwd to a 1014 mb frontal low over OH, will merge with a developing bay breeze and move swwd to the vicinity of the Roanoke River between 22Z-00Z. A separate, srn stream front extending from cntl TX enewd and across the lwr MS and TN Valleys, to a 1013 mb frontal low over Middle/wrn TN, then ewd across nrn GA and the Piedmont of the Carolinas, will move little through the period. With no airmass change from Thu and continued influence of ridging aloft, today will be persistently, unseasonably warm, with temperatures continuing at 10-15F above average - mid 80s to around 90. Showers and isolated storm will focus today along both fronts noted above, including into the NC nrn Coastal Plain and far ne Piedmont early this evening and also with diurnal heating along a differential heating zone evident in late morning visible satellite and surface observational data along the srn stream front from AGS to HKY. The latter activity, should it indeed develop, would then be steered in weak wswly steering flow and into the srn and wrn NC Piedmont late this afternoon-evening. Areas of persistence fog and low stratus will likely redevelop into the srn-cntl Coastal Plain and ern Sandhills tonight, while a separate area of post-frontal, very low stratus will develop behind the backdoor front across the ne Piedmont and nrn Coastal Plain. Temperatures tonight will remain unseasonably mild and mostly persistent in the upr 50s to mid 60s. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... As of 230 PM Friday... Aloft, the sub-tropical ridge will stall along the eastern seaboard through Sat night. A southern stream disturbance will move into the Southeast US on Sat, then lift newd through the area as a sheared out northern stream s/w moves through the OH Valley/Great Lakes Sat night. The sub-tropical ridge will shift offshore and breakdown Sun/Sun night as the disturbances move through the mid-Atlantic and Northeast US. Another southern stream s/w will develop over the southern Plains on Sun, then move eastward into the lower/mid-MS Valley Sun night. At the surface, as high pressure sits over the New England coast, the backdoor cold front is expected to stall over nrn/nern NC through Sat and into Sat night then lift northward late Sat night/Sun. The high should move eastward over the Atlantic as a low moves through the Great Lakes and into the Northeast Sun/Sun night. Precipitation/Convection: Still fairly high confidence/chances for showers and possible storms Sat and Sun. Best threat for storms will be across the Piedmont, mainly along and south of the surface boundary, where surface-based CAPE will be maximized. Bulk shear still appears weak, and PWATs are expected to range from 1.4 to 1.8 inches. Do not expect the entire day to be a wash-out by any means, and Sat could start dry for most, but there will be a chance for showers across all of central NC, with greatest coverage from Sat eve through Sun aft. Highest chances NW, lowest SE. Given the high PWATs and scattered, somewhat disorganized mode of convection, isolated locations could receive locally heavy rainfall, with any potential for minor flooding issues largely limited to urban areas. Temperatures: A bit tricky on Sat, as there is some bust potential north of the front. Widespread overcast skies should somewhat limit heating as well. For now expect highs to range from the mid 70s along the NC/VA border to mid 80s SE. Sat night temps should be continued mild, mainly in the low to mid 60s. On Sun, with the retreat of the front northward, areas across the north may be a few degrees higher than Sat, but given the expected showers/storms through the day, temps may otherwise be limited. Highs in the upper 70s north to low 80s south. && .LONG TERM /MONDAY THROUGH THURSDAY... As of 329 PM Friday... The extended forecast upper pattern will largely include mid-level ridging over the eastern US. A stronger short-wave will move over the area Monday into Tuesday increasing rain chances. After relatively zonal flow Tuesday, mid-level ridging will then re- amplify over central NC through the end of the extended. Another potentially stronger trough may approach late in the period. Monday/Tuesday: A potent mid-level short-wave and associated vorticity max is forecast to move across the southern Appalachians Monday afternoon. Mid-level height falls will maximize over us later Monday afternoon/early evening coinciding with peak heating/instability. At the sfc, a piedmont trough will develop Monday afternoon which, in combination with forcing aloft, should help to focus showers and storms across our area. Bulk layer shear will be much too weak to support severe storms, but given the presence of anomalous PWAT (150 to 200 % of normal) any storm that develops could produce brief heavy downpours and gusty winds. POPs should decrease late Monday night/early Tuesday morning as flow aloft turns a bit more nwly and the atmosphere stabilizes. In absence of upper forcing aloft, rain chances Tuesday afternoon will largely rely on diurnal shower/storm development which should remain mostly scattered. Temperatures Monday will peak in the mid to upper 80s, increasing into the upper 80s by Tuesday afternoon. Wednesday/Thursday: The mid-level ridge will re-establish itself Wednesday and Thursday as temperatures soar into the lower to mid 90s. The NBM is particularly stoked about 90 temps for highs these days with >80% of it's members reaching this threshold for much of this area. The LREF (GEFS, GEPS, EPS) is a little less enthused on Wednesday, but does suggest decently high probabilities on Thursday (generally 40 to 60 % across the area). Otherwise, anomalous moisture will remain in place Wednesday/Thursday which should promote a continuation of low-chance POPs each afternoon. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... As of 235 PM Friday... Isolated to widely scattered showers and storms will focus this afternoon-evening along a differential heating zone and surface trough over the Foothills and wrn Piedmont of NC (including at INT/GSO) and also along a backdoor cold front that will reach the Roanoke River vicinity (including near and just north of RWI) around sunset. Areas of very low overcast and fog will likely redevelop through sern NC, including to around FAY between 10-12Z, in a persistence regime of humid, sly flow there. Meanwhile, a separate area of post-frontal, low stratus in enely flow, will develop behind the backdoor front and reach RWI and all Piedmont sites around the same time (between 10-12Z). Ceilings in both regimes should then lift through MVFR through midday Sat, during which time showers/ storms are apt to redevelop with diurnal heating. The greatest concentration of that convection should be along the front, which will likely become quasi-stationary between I-85 and US-64 on Sat. Outlook: IFR-MVFR ceilings are likely to redevelop each night- morning through Monday, as are scattered to locally numerous showers/storms each afternoon-evening. && .CLIMATE... Record High Temperatures: May 3: KGSO: 92/1959 KRDU: 93/1959 KFAY: 95/1913 Record High Minimum Temperatures: May 4: KGSO: 65/2022 KRDU: 68/1938 KFAY: 68/1942 && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...MWS NEAR TERM...MWS SHORT TERM...KC LONG TERM...Luchetti AVIATION...MWS