####018005174#### FXUS66 KPDT 082350 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 450 PM PDT Wed May 8 2024 Updated Aviation Discussion .SHORT TERM...Tonight through Friday night...Quiet weather accompanied by a notable warming trend is forecast through the period as an amplified ridge of high pressure influences the region. Synoptically, the region is currently under northeast flow aloft, located between an amplified offshore ridge that is nosing into the PacNW and a broad closed low centered over the Great Plains. Tonight, cloud cover and precipitation chances will diminish across the region as wraparound moisture decreases. Ensemble guidance is in excellent agreement that a closed low will develop northwest of the Four Corners region tomorrow and retrograde over the Desert Southwest through Friday. This will set up a textbook Rex block over the West with the aforementioned amplified upper-level ridge building across the PacNW. The result will be warming accompanied by dry conditions and offshore- oriented pressure gradients. Locally breezy northeast winds are forecast tomorrow, especially along wind-prone ridges. The main tangible consequence of the ridge will be warming temperatures with a 5-10 degree warming each afternoon Thursday and Friday. Confidence is very high (70-99% chance per NBM probabilities) that Friday afternoon highs will exceed 80 degrees in the lower elevations (especially the Columbia Basin, Yakima and Kittitas valleys, and along the lower elevations of the Blue Mountain foothills). Raising the threshold, confidence is medium- high (50-80% chance) that Friday afternoon highs will exceed 85 degrees in the lower Columbia Basin and Yakima Valley. In the populated areas of central Oregon, chances of 80 degrees are lower (15-50%) and are highest for the Redmond area. Plunkett/86 .LONG TERM...Saturday through Wednesday...Models in pretty good agreement through the period. However, they do differ on the timing of a weak shortwave Sunday night into Monday and in the strength of a developing upper level ridge off the coast. The EOFs show the greatest variance (50+%) Tuesday and Wednesday. In fact, by Wednesday, the WPC cluster analysis shows 57% of the members believe in an upper level ridge off the coast while 43% depict a more zonal flow pattern. Depending on the pattern, we could be near normal or 10-15 degrees above normal by the middle of next week. In addition, the ensemble means are leaning towards more zonal flow by Wednesday. NBM is trending more to normal temperatures (slightly above normal at this time) as well which is not surprising given aforementioned discrepancies. The deterministic models are surprisingly in relative alignment with a weak shortwave moving through Sunday evening. The ECMWF shows another shortwave moving through the northwesterly flow Monday afternoon. The disturbances are so weak their only impact on our CWA should be an increase in cloud cover and slightly cooler temperatures. However, the Washington Cascade Crest may see some isolated showers on Wednesday if more westerly flow develops. In summary, the extended period will start off with an upper level ridge weakening but daytime highs still 10-15 degrees above normal Saturday and Sunday. Several shortwaves should continue to flatten the ridge with more zonal flow developing, dropping highs back down to 5 degrees or so above normal. Another amplifying ridge could develop (low to moderate confidence) over the eastern Pacific, but resulting in a "cooler" northwest flow pattern aloft for our CWA. There will be some hydrological concerns over the weekend as an upper level ridge continues to produce above normal temperatures over the area. This will provide ideal conditions for melting some of our winter snowpack. All rivers will see rises, but portions of the Naches River are expected to recede bankfull by Saturday or Sunday. Earle/81 .AVIATION...00Z TAFs...VFR conditions to prevail through the period. Periodic CIGS of few-bkn AOA 20kft AGL will impact sites through the period. Breezy winds between 12-15kts and gusts up to 20kts will continue at site RDM/BDN through 4Z, becoming less than 12kts the remainder of the period. Everywhere else winds will be 12kts or less, with winds mostly from the north tomorrow...except site DLS where winds will be from the east. Lawhorn/82 && .PRELIMINARY POINT TEMPS/POPS... PDT 40 73 46 79 / 0 0 0 0 ALW 42 78 49 83 / 0 0 0 0 PSC 46 81 52 86 / 0 0 0 0 YKM 42 80 48 85 / 0 0 0 0 HRI 42 79 49 85 / 0 0 0 0 ELN 43 78 49 84 / 0 0 0 0 RDM 34 71 40 79 / 0 0 0 0 LGD 37 71 43 77 / 0 0 0 0 GCD 33 72 42 77 / 0 0 0 0 DLS 47 80 52 86 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...86 LONG TERM....81 AVIATION...82 ####018005828#### FXUS63 KARX 082350 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 650 PM CDT Wed May 8 2024 .KEY MESSAGES... - Heaviest rainfall for tonight continues to shift south with the highest rainfall amounts across northeast Iowa where 1 to 2 inches are expected. Probabilities for 0.1" or greater drop dramatically north of I-90. - Scattered showers, a few storms, tracking southeast across the area Fri afternoon/evening, mostly for WI. - Periodic rain chances from the weekend into next week, but mostly "low end" (20-40%) at this time. Temps trending 5 to 10 degrees above the seasonable normals. && .DISCUSSION... Issued at 220 PM CDT Wed May 8 2024 * REST OF TODAY AND TONIGHT: Storms, Heavy Rain Shifting Further South Pleasant conditions are expected for the rest of the afternoon as fairly robust diurnal mixing will allow for some clearing in sky cover which should allow temperatures to warm into the 70s for much of the region. As a surface low moves south of the region, a mid- level frontogenesis band will entrain itself across the southern portion of the local area which when combined with some 850mb moisture transport and precipitable water values of just over 1" in northeast Iowa as shown in the recent deterministic model runs (NAM/GFS/RAP). This will allow for fairly efficient rainfall where the frontogenesis forcing is maximized. One recent forecast trend that has created some challenge is the CAMs beginning to shove much of the higher probabilities for heavier rainfall further south. Currently, probabilities in the 08.12z HREF show modest probabilities (40-70% chance) for 1 inch of QPF or greater across southern portions of the local area in northeast Iowa. Additionally, the probabilities in the 08.12z HREF of 0.1" or greater sharply drops off north of I-90 (roughly 40% at La Crosse) where much of the 08.18z CAMs show a tight gradient in the northern edge of the frontogenesis band. As a result, confidence remains low with how far north more substantial precipitation will get but areas where the forcing is best realized across northeast Iowa and points south could see 1 to 2 inches of rainfall with locally higher amounts possible. The strong to severe storm threat with convection appears to be fairly minimal across our region with forecast soundings showing only a few hundred J/kg of MUCAPE, so while some rumbles of thunder are likely, much of the severe threat will be outside the local area. * FRIDAY/FRIDAY NIGHT: another round of showers, isold storms The medium/long range guidance has been in good agreement with dropping a shortwave trough south/southeast out of southern Canada, sliding it across the upper mississippi river valley Friday afternoon/night. Preceding warm air advection is weak with not well defined Fgen along the leading edge of the shortwave. The system brings enough saturation with it to fuel rain chances. Decent shear with longish, straight line hodographs, but only about 250-500 J/kg of MUCAPE. So a smattering of storms with the showers, but not expecting anything too perky. Dry sub layer does suggest some enhanced gustiness possible, depending on timing of any storm (noctural sfc inversion acting as a deterrent). * WEEKEND-EARLY NEXT WEEK: periodic rain chances, seasonable Active, fairly zonal flow sets up for the weekend into the middle part of the new week. EPS and GEFS continue to push various ripples in the upper level flow across/near the region - with some expected differences in timing/location. Nothing too organized at the moment (locally), nor much for a tap into southernly moisture. Plenty of saturation though to fuel occasional rain chances. For now, the model blend will paint low end chances (20-40%), which are reasonable given the time frame/strength of the shortwaves/model variances. Enough instability to spark some storms too, but currently no day is holding much for a severe threat (all subject to change of course). For temps, the flow points to a return to normal to a few degrees above. GEFS and EPS have trended this way, although the GEFS has remained the cooler of the two with 75% of its members generally at or below the early May normals. The grand ensemble of members suggests a 30-40% for 70+ highs for next week, but driven up by a warm Canadian solution. Meanwhile, the NBM tops the suite of model guidance (5 to 10 degrees above normal), riding some of the top 10% of the EPS and GEFS which push temps into the 80s. No anomalous fetch of warm air on the horizon per the NAEFS and EPS. The NBM isn't "out to lunch" if we have mostly sunny days and keep any rain chances outside of the afternoons. For now, will ride with the NBM...but not completely sold on its output yet. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 645 PM CDT Wed May 8 2024 Showers and isolated thunderstorms lift northward and affect areas mainly south of a RST to KDLL line overnight, with isolated showers lingering through the day on Thursday. The highest probability for ceiling/visibility restrictions overnight will be closer to an area south of FXY to PDC. Ceilings areawide gradually lower to MVFR by morning (about a 20 to 30 percent chance of IFR ceilings at RST), improving in the afternoon. Winds will remain at or less than 10 kts through the period, backing from the east to the north by Thursday afternoon. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Rieck AVIATION...Skow ####018004136#### FXUS62 KTBW 082350 AFDTBW Area Forecast Discussion National Weather Service Tampa Bay Ruskin FL 750 PM EDT Wed May 8 2024 ...New UPDATE, AVIATION, MARINE... .UPDATE... Issued at 750 PM EDT Wed May 8 2024 The dry air aloft has helped to limit convective activity once again today with only a few isolated showers early this evening along the sea breeze as it moved inland over southeastern Pasco, northeastern Hillsborough, and western Polk Counties. For the remainder of the night expect mostly clear to partly cloudy skies across the area with lows only dipping to around 70 to the mid 70s. Thursday looks like another warm and rather humid day, but the dry air aloft will persist and winds will turn to southwest and become breezy so not expecting any convection in our area. Current forecast looks on track with no changes needed. && .AVIATION... (00Z TAFS) Issued at 750 PM EDT Wed May 8 2024 VFR conditions are expected through the period, but could see some patches of MVFR ceilings late tonight into early Thursday morning. Southwest winds this evening will shift to southerly at 5 to 10 knots overnight and then increase to 10 to 15 knots late Thursday morning before shifting to southwest during the afternoon. && .MARINE... Issued at 750 PM EDT Wed May 8 2024 Winds generally remain 15 knots or less and out of the south to southwest for the rest of the work week. A front will start to work its way through late Friday which will bring a chance for a few showers and thunderstorms. Behind the front winds will shift to northwest Saturday and then northeast on Sunday as high pressure moves across the southeast states. && .DISCUSSION... Issued at 250 PM EDT Wed May 8 2024 The big story for the rest of the work week will be the heat away from the coastal areas. Ridging over the area is causing some drier air and keeping showers away while also turning the heat up. Inland areas of the CWA can expected highs in the mid to upper 90's today through Friday. As we go through the day on Friday a weakening cold front will be pushing into the area. The best chance to see some significant showers and storms will be over the Nature Coast in the morning and early afternoon hours. Once it works through the rest of Florida in the evening and overnight hours much of the shower activity will be gone, but an isolated storm can not be ruled. This front will only drop our high temperatures a few degrees for the weekend, so we can still expect highs in the upper 80's to mid 90's. The big change will be Sunday morning where most of us will wake up comfortably in the 60's. However, temperatures will warm up quickly so if you sleep in you will miss it. Our next frontal system looks to try to push through during the middle of next week. However, ahead of the front we will see added moisture which will aid in some showers and storms with the better chances Tuesday and Wednesday. && .FIRE WEATHER... Issued at 250 PM EDT Wed May 8 2024 Our main concern over the next few days will be critical RHs. We will have isolated spots of critical RHs throughout the work week. However, the more widespread critical RHs will be after the frontal passage late on Friday. Saturday the lowest RHs should remain in the interior, but Sunday we should see critical RHs through all of our CWA as winds turn northeasterly. Winds will be light so no need for Red Flag and moisture will return early next week. && .PRELIMINARY POINT TEMPS/POPS... TPA 76 89 77 88 / 0 0 0 20 FMY 74 93 75 90 / 0 0 0 0 GIF 74 95 74 93 / 10 0 0 20 SRQ 75 87 76 89 / 0 0 0 10 BKV 70 92 71 90 / 0 0 0 40 SPG 77 87 79 86 / 0 0 0 20 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/AVIATION/MARINE...Close DISCUSSION/FIRE WEATHER...Shiveley DECISION SUPPORT/UPPER AIR/CLIMATE...Delerme ####018004299#### FXUS63 KGID 082353 AFDGID Area Forecast Discussion National Weather Service Hastings NE 653 PM CDT Wed May 8 2024 .KEY MESSAGES... - Showers and thunderstorms will be possible (up to a 25% chance) this afternoon into Thursday night across parts of the area. No severe weather is expected. - Showers and thunderstorms will also be possible (up to a 60% chance Sunday afternoon) Saturday night through Tuesday night. Severe weather is not expected at this time. - High temperatures will range from the mid 60s to low 80s and low temperatures will range from the upper 30s to mid 50s. && .DISCUSSION... Issued at 249 PM CDT Wed May 8 2024 Today and tonight... A big upper trough extends from the West Coast to the Upper Midwest. An upper low is centered over South Dakota with mostly northwest winds across south central and central Nebraska and north central Kansas. Temperatures across the area are in the 60s and 70s. Showers with maybe an isolated thunderstorm or two are possible (up to a 20% chance) this afternoon and evening across mainly areas north of the Nebraska Tri-Cities area. No severe weather is expected. Low temperatures tonight will be mostly in the 40s with northerly winds. Thursday through Saturday... Northerly winds will continue across the area on Thursday with highs similar or slightly cooler than today. Rain and storms will be possible (up to a 25% chance) Thursday afternoon and evening. Low temperatures in the 40s are again expected Thursday night with light northwest winds and mostly clear skies. The portion of the upper trough over the western part of the country will get cut off from the trough over the Upper Midwest. Nebraska and Kansas will be in between these two features on Friday. Northwest winds are expected to continue across south central and central Nebraska and north central Kansas on Friday with high temperatures mostly in the 70s. Low temperatures will continue to be in the 40s Friday night. A slight warm up is expected for Saturday with high temperatures mainly in the mid to upper 70s. Winds will generally be out of the northwest to southwest with mostly sunny skies on Saturday. Saturday night through Tuesday night... Low temperatures Saturday night will range from the mid 40s to mid 50s with south to southwest winds. Rain and thunderstorm chances will increase (up to near 50%) across the area beginning Saturday night. Rain and storm chances (up to around 60%) continue during the day on Sunday as an upper trough moves over the southern and central Plains. High temperatures will be similar or slightly cooler on Sunday than the previous day. Low temperatures Sunday night will be in the 40s and 50s. Rain and storm chances (up to around 55%) will continue through Sunday night as the upper trough remains over the southern and central Plains. Rain and storm chances remain (up to around 50%) on Monday with highs similar or slightly higher than the previous day. Temperatures are expected to increase slightly next Tuesday ahead of an approaching cold front. Rain and storm chances will continue (up to around 40%) into Tuesday and Tuesday night. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 650 PM CDT Wed May 8 2024 Tonight: Ongoing CU and brzy NW winds should both decr within the next 1-2 hrs. Rest of the overnight should be fairly quiet with mostly clr skies and N wind 6-9kt. Confidence: High. Thursday: Main aviation concern will be the potential for a low level cloud deck - MVFR to perhaps even briefly IFR based on LCL heights 12-14Z - to move in from the N. Latest NBM probs for at least MVFR CIGs are only 15-20%, so not enough confidence to go beyond SCT at this time. Plan view plots show best potential for stratus or stratocu to hold off until closer to 15Z, which by that point LCLs would be on the rise. Winds will bec brzy out of the N after sunrise, sustained 13-16kt, gusts 20-25kt. Confidence: Wind - high, CIGs - low. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ DISCUSSION...Schuldt AVIATION...Thies ####018007154#### FXUS62 KFFC 082354 AFDFFC Area Forecast Discussion National Weather Service Peachtree City GA 754 PM EDT Wed May 8 2024 ...New 00Z Aviation Discussion... .UPDATE... Issued at 528 PM EDT Wed May 8 2024 A Tornado Watch is in effect for portions of far north Georgia until 12 AM EDT tonight. Low-level shear of 20-25 kts is present across portions of middle Tennessee, near modified outflow from storms earlier today. This low-level shear along with deep-layer bulk shear of 35-40 kts and SBCAPE values of 2000-2500 J/kg has been sufficient for the development of discrete supercells at the time of this writing. As outflow propagates south and east into similarly unstable air in far north Georgia, it will promote the development of scattered thunderstorms. It is worth noting that 0-1 km SRH values in this area will range from 100-150 m2/s2. Thunderstorms that occur this evening will have the potential to become strong to severe, capable of producing damaging wind gusts, hail, and isolated tornadoes. King && .SHORT TERM... (This afternoon through Thursday) Issued at 242 PM EDT Wed May 8 2024 A nearly stationary frontal boundary currently extends from S New England SW to near Kansas City. Scattered to numerous thunderstorms extend across NC and TN to MO in a very moist and unstable warm sector. A few discrete strong to severe storms have also fired across extreme NE GA and NW SC. Mid-level flow is fairly zonal, with stronger short waves and/or lows well to the N. However, disturbances farther S continue to force convection in the juicy environment. Models continue to indicate a shortwave dropping SE across N GA late tonight. Many high resolution models bring thunderstorms S later tonight into an environment with MUCAPES of 2000 J/kg or higher and effective shear values of 30-40 knots. This should continue to support strong to severe thunderstorms, with wind and hail the main threats. There will also be a risk of isolated tornadoes, mainly across the extreme N. Heavy rainfall will also be a threat, as storm motion will likely nearly parallel the orientation of the axis of storms. As these storms continue to progress S, some guidance weakens them late tonight and early Thu. However, this solution is highly uncertain given the continuing instability and shear across the area. Even if these storms do weaken, there will likely be a lingering boundary formed by the cool pool leftover from the storms that will act as an additional focusing mechanism for storm redevelopment later in the day on Thu. Instability and shear near and S of the old outflow boundary will be high. The greatest uncertainty with this feature will revolve around how stable the air is N of the old outflow boundary and how that limits convection initiation farther to the N. A potent shortwave will move across the S portion of the area late Thu night and into Fri, supporting more strong to severe thunderstorms across the S portion of the area. The S boundary of the cool pool will likely help focus these storms. Due to the slow advancement of a cold front to the S and the E storm motion along a W- E aligned line of storms, locally heavy rainfall is definitely possible. SEC && .LONG TERM... (Friday morning through next Tuesday) Issued at 242 PM EDT Wed May 8 2024 Highlights: -Shower and thunderstorm activity continues on Friday mainly for the southern two-thirds of the forecast area. -Drier weather briefly returns this weekend before rain makes another appearance early next week. Latest hi-res guidance is coming into better agreement with bringing an MCS originating in East TX across the Southeast states Thursday night through early Friday morning. With decent instability, another surge of moisture (PWs surging between 1-2" range) and plenty of shear another early morning wind threat Friday morning (start of the long term period) will be possible for areas I-20 southward. As stated in previous forecast discussions, guidance tends to struggle with exact placement and evolution of MCS features thus there are a few uncertainties with regards to the exact path of this overnight/early morning MCS. Additionally, what occurs Friday morning will impact what occurs for the remainder of the day -- i.e. redevelopment across the southeast in the vicinity of the southward moving cold front or lack of development due to a 'worked over' environment. In addition to the severe threat localized flooding will also be a concern given multiple rounds of active weather in the short term and the start of the long term period. Will continue to monitor in later forecast updates. Otherwise, a cold front that will be situated across North GA will continue migrating southward as a shortwave to our north swings eastward. This will act to gradually bring any shower or thunderstorm activity to an end by Friday evening. A brief period of dry and slightly cooler weather is expected this weekend as we return to northwest flow aloft. Rain chances look to return to the region next week as another low pressure system developing in the Southern Plains moves eastward. 07 && .AVIATION... (00Z TAFS) Issued at 745 PM EDT Wed May 8 2024 Conditions are VFR at all TAF sites as the evening begins, with a cu field between 040-060 expected to persist for the next couple of hours. MVFR ceilings are expected to develop in the early morning, between 08-10Z. SHRA/TSRA will begin to spread into far north Georgia late tonight, advancing towards the metro ATL area during the early morning hours. A PROB30 for TSRA is being carried from 10-15Z at ATL. Some storms within this line could be strong to severe, capable of producing gusty winds and hail. Have maintained higher the wind speeds/gusts in PROB30 along with reducing visibilities and ceiling heights. Showers will linger behind the initial push of thunderstorms, with ceilings slow to improve. Winds will be primarily SW at 5-9 kts through the evening, increasing to 8-12 kts in the early morning on Thursday and through the remainder of the day. //ATL Confidence...00Z Update... Medium confidence on all elements. King && .PRELIMINARY POINT TEMPS/POPS... Athens 68 84 64 80 / 40 80 30 40 Atlanta 69 84 65 79 / 40 80 40 40 Blairsville 62 78 57 70 / 80 90 30 30 Cartersville 65 84 61 77 / 60 80 40 30 Columbus 72 88 68 84 / 20 70 50 60 Gainesville 68 82 65 78 / 60 80 30 30 Macon 70 86 67 82 / 10 70 40 60 Rome 67 85 62 77 / 70 80 40 20 Peachtree City 68 84 63 80 / 30 80 50 40 Vidalia 70 91 71 85 / 0 60 50 80 && .FFC WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...SEC LONG TERM....07 AVIATION...King ####018009703#### FXUS61 KOKX 082354 AFDOKX Area Forecast Discussion National Weather Service New York NY 754 PM EDT Wed May 8 2024 .SYNOPSIS... A cold front stalls south of the area tonight before a low pressure approaches the area from the west on Thursday. The low lingers over the area through Friday night. A series of lows move through the vicinity of the region this weekend. High pressure builds offshore for early next week before another low potentially moves in for the middle of next week. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... Forecast mainly on track with most remarkable changes made to the POPs for showers and thunderstorms as well as cloud coverage. Surface based CAPE analysis indicated around 500 to 1000 J/kg across mainly the Southern CT portion of the forecast region. Also, boundary layer is quite dry across western sections of the region but relatively more moisture for eastern parts of the region from New Haven through New London CT as well as Eastern Long Island. For these locations going into early evening, there are slight chance to chance POPs for showers and thunderstorms. The instability is expected to decrease going into early this evening which limit how strong these thunderstorms could get. A strong thunderstorm however cannot be ruled out with small hail and gusty winds with some shear to work with. Any storms come to an end by late this evening with a cold front moving through. The cold front will dry out the airmass, though eastern areas may remain moist enough to result in some patchy fog later tonight with otherwise decreasing cloud coverage. Lows tonight will be generally in the 50s, with the warmest spots in the west. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... Mid-level energy upstream will force a surface low pressure system to move across the Ohio Valley and approach the area into Thursday. Showers may approach the area during the morning but will become gradually more likely into the afternoon. The latest model guidance has trended much of the shower activity with this system to the south, which may hold off much of the shower activity off until the late afternoon or evening, especially for areas north and east. Highs Thursday will be fairly seasonable with temperatures in the middle 60s to low 70s. As the center of the low pressure moves into the area Thursday night, shower activity will increase substantially so that much of Thursday night through Friday morning will have widespread showers, some of which may be locally heavy with some embedded convective elements possible, though thunder is not likely. Though there is some uncertainty as to the exact placement of the low on Friday, it looks to meander in the general area as an upper level trough moves overhead, the surface low will spin over the area on Friday resulting in additional shower activity during much of the day. As such, temperatures will be below average with highs only in the middle 50s. The shower activity should begin to wind down from west to east overnight Friday and into early morning Saturday. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... From analysis of large scale deterministic weather prediction models of the GFS, ECMWF, and the Canadian models, the following features were noted from the lower to upper levels. The upper level jet is shown to remain south of the region this weekend and then with more ridging next week, parts of the upper level jet traverse the local area. Mid level trough south of region Saturday morning, then shifts east during the day with brief ridging as the local area will be in between shortwaves. Next shortwave moves in Saturday night with another moving south of the region Sunday. The larger trough encompassing these shortwaves and periodic positive vort maxima will be lingering across the region through Sunday. This trough then moves east of the region Sunday night. Overall the larger scales convey a mid level ridging trend taking place for early into middle of next week for the local area. For Monday night into early Tuesday next week, a subtle small shortwave embedded within the ridge is forecast to move across. By Wednesday, especially late day into Wednesday night, next trough could be potentially moving in from the west. At the surface, low pressure moves south and eventually southeast of the region Saturday. Weak pressure gradient follows across the local region. This weak high pressure will be brief as low pressure approaches Saturday night and moves near to south of the area early Sunday. Low pressure passes southeast of the region Sunday into Sunday night. Offshore high pressure briefly builds in late Sunday night into early Monday and then moves farther offshore as another wave of low pressure approaches Monday afternoon into Monday night. This low pressure will be weak and will traverse the local area late Monday night into early Tuesday. Another low may approach the area next Wednesday. Chances of rain showers are forecast much of this weekend and for Sunday when relatively the coldest air aloft moves across, put in a slight chance of thunderstorms for the mid afternoon into early evening hours. Mainly dry conditions are forecast Sunday night through early Tuesday. Then, next chance of rain showers is forecast Tuesday afternoon into the midweek timeframe. Temperatures for the weekend exhibit less of a diurnal trend, and generally expected to be below normal for daytime hours and then near to above normal for next week. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... A cold front moving through the terminals at 23Z will push to the south tonight before stalling through the mid Atlantic region. A wave of low pressure tracks along the stalled boundary late Thursday afternoon into Thursday night. Mainly VFR, with the exception of KGON where a thunderstorm and MVFR is possible through 01Z, and then there is a chance of IFR stratus after 01Z to 04Z/05Z. Then late in the forecast there is a chance of showers, however conditions remain VFR until later Thursday evening. Winds ahead of the cold front remain from the SW to W 10-15kt with occasional higher gusts. Behind the front winds shift to the NW and then N late this evening and into early Thursday morning. Winds become light Thursday afternoon, and have low confidence in directions. A sea breeze is possible. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Low confidence wind forecast for Thursday afternoon as winds may be anywhere from NE to E/SE to S, under 10kt. A sea breeze is possible at KJFK. OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY... Thursday Night: MVFR or lower developing with a chance of showers. Friday: MVFR or lower with showers likely. Saturday and Sunday: Chance of MVFR or lower in showers. Monday: Mainly VFR. Isolated showers possible at KSWF. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Winds and seas are expected to remain below SCA conditions through Thursday. Seas and winds may approach SCA criteria with winds near 20 kt and seas approaching 5 feet. Any marginal SCA conditions diminish once again into Friday and stay below SCA through at least Friday night. For the long term period of Saturday through Monday night, SCA conditions are probable on the ocean, due to mainly seas, for much of the timeframe. Wind gusts stay mainly below SCA thresholds. Sub- SCA conditions are forecast for non-ocean zones. && .HYDROLOGY... Upwards of 0.5" to 1" of rainfall is possible for western portions of the area Thursday night through Friday but are not expected to result in any hydrologic impacts. No hydrologic impacts are expected during the long- term forecast period. && .TIDES/COASTAL FLOODING... Astronomical tides run high the next few days with the new moon from last night. Minor flood benchmarks are likely to be exceeded during the evening high tide cycles tonight through Friday night for southern Nassau, southern Queens, and Fairfield and Westchester counties with inundation up to a foot. Coastal flood statements will be in place for tonight's high tide for Newark Bay in Hudson county and southern Queens with water levels perhaps just touching minor benchmarks. Localized moderate flooding is possible during Fri evening's high tides in the most vulnerable spots of southern Nassau, with advisories and statements likely in similar locations tonight, and perhaps including SW Suffolk and portions of the north shore of Long Island in subsequent evening high tide cycles through Friday. Statements may also be needed for Thursday and Friday evening for portions of coastal NE NJ and Staten Island. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Coastal Flood Advisory from 11 PM this evening to 2 AM EDT Thursday for CTZ009. NY...Coastal Flood Advisory from 11 PM this evening to 2 AM EDT Thursday for NYZ071. Coastal Flood Advisory until 11 PM EDT this evening for NYZ179. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/MW NEAR TERM...JM/MW SHORT TERM...MW LONG TERM...JM AVIATION...MET MARINE...JM/MW HYDROLOGY...JM/MW TIDES/COASTAL FLOODING... ####018003706#### FXUS63 KBIS 082355 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 655 PM CDT Wed May 8 2024 .KEY MESSAGES... - Isolated to scattered rain showers continue this evening, especially in northwestern North Dakota. - A transition to warmer and drier weather is expected Thursday through the weekend. - Confidence is increasing that more widespread precipitation chances will return to the region during the first half of next week. && .UPDATE... Issued at 639 PM CDT Wed May 8 2024 A few showers continue to rotate around the low over far southern North Dakota, and over far north central into northwest North Dakota. Previous forecast reflected this quite well, so only change was to adjust precipitation chances a little bit based on current trends. && .DISCUSSION... Issued at 206 PM CDT Wed May 8 2024 Low pressure that was vertically stacked over southwestern ND/northwestern SD has become elongated as it quickly shifts southeast through the remainder of today into tonight. During this time, the area will remain in cyclonic flow resulting in continued isolated to scattered showers this afternoon and evening, especially in the northwest. There remains a low chance that a thunderstorm or two could creep up into the southern James River Valley of ND later today. However, the best thunderstorm potential looks to remain south of the forecast area. For Thursday, a quick-moving ridge on a west to east axis passes through the area bringing warmer temperatures to the region. A weak trailing shortwave will flatten the ridge and bring a 20 percent chance of showers primarily to western ND Thursday afternoon. A few showers could then continue in southwestern to central ND during the evening. Beyond that, conditions look mostly dry through the weekend as flow aloft becomes northwesterly. During the weekend, models are in fair agreement that somewhat weak upper low pressure will develop over the Four Corners region and progress eastward, while more organized low pressure passes through south central Canada towards the southern Hudson Bay. A trailing trough off the Hudson Bay low brings the best chances of precipitation towards the middle of the week. Regardless, the main thing is that starting Sunday night, multiple waves of energy may bring precipitation to the forecast area. A lack of agreement means exact details on timing, precipitation totals, and thunderstorm potential are not yet known. Temperatures will continue a gradual warming trend into this weekend. Highs Thursday and Friday will be mostly in the mid to upper 60s. By the weekend, however, most locations should see low to mid 70 degree readings. A cooling trend is then favored to start the next workweek as aforementioned troughing may bring cooler air to the region. That said, NBM 25th/75th percentile spreads remain semi-large (around 10 degrees) for high temperatures next week, so some uncertainty certainly does exist. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 639 PM CDT Wed May 8 2024 Localized MVFR ceilings are possible over far southwest and south central North Dakota, along with over far north central into northwest North Dakota this evening as a few isolated showers continue to move through. Isolated showers are again possible over western North Dakota Thursday afternoon. Otherwise, VFR conditions are expected. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...JJS DISCUSSION...Telken AVIATION...JJS ####018008274#### FXUS61 KPHI 082355 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 755 PM EDT Wed May 8 2024 .SYNOPSIS... A front will move south of the area this evening and stall near southern Delaware and southern Maryland through Thursday, before an area of low pressure moves along it later Thursday. The front then remains to our south through Friday, before another low pressure system moves near the area later Friday into Friday night. Yet another weak low pressure system may move near the area Sunday, before high pressure builds south of the Mid-Atlantic region Sunday night into Monday. More unsettled weather could impact our area Tuesday into Wednesday as a storm system approaches the area. && .NEAR TERM /THROUGH THURSDAY/... 4PM discussion... Breezy the rest of the afternoon with southwest to west winds gusting 20-25 mph. Broad upper level pattern is more zonal overhead and with an airmass in place is quite dry through the column, kept afternoon POPs below 15 percent. That said, can't fully rule out a rogue gusty shower before sunset. As we head into tonight, initial area of low pressure continues moving east off the coast of New England and out to sea. This will push a weak cold front offshore through the evening. Meanwhile by the overnight period the next wave of low pressure will be approaching as it moves eastward through the midwestern states and this will start to push the front back to the north as a warm front. Clouds will once again be on the increase by the late overnight and it's possible we could see some showers start to enter the region towards dawn, however the trend has been slower with these arriving later. Expect lows ranging from the 50s north to the low 60s south. Forecast guidance continues to step back from the severe weather potential for Thursday, though the situation remains in a bit of a flux. A few things are working in favor for a diminished severe potential: 1) Guidance continues to trend further south with the track of our system, lending to a cooler, cloudier day 2) Convective-allowing models are suggesting an overnight MCS across the southern Mid Atlantic will lift northward along a warm front and arrive around or shortly after daybreak Thursday, largely robbing our region of instability for much of the day. Because so much of the aforementioned elements depend on the evolution of severe weather occuring across the Tennessee River Valley today, there remains a higher than usual level of uncertainty within our forecast. At any rate, the warm front and how far north it is able to travel will be the limiting reagent for our weather tomorrow. North of the front will remain cloudy, showery, and overall dreary with temperatures stuck in the mid to upper 60s with an easterly flow. South of the front, warmer temperatures in the 70s with diurnal heating will lend to more instability developing through the day, resulting in a higher severe weather risk. At this point in the forecast, the frontal boundary is expected to stall out just south of the Delmarva Peninsula, keeping much of the severe weather potential in our forecast area suppressed. A few elevated storms cannot be ruled out, especially across the Delmarva and southern NJ, but the severe weather threat, if this forecast holds, is expected to be lower than previously forecast. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/... Unsettled weather will continue for the Thursday night through Friday night time period as our area will be north of a frontal boundary located to our south, with a trough extending northward to our west. An area of low pressure is forecast to develop along this trough and move along the frontal boundary to our south through Friday night. There will be plenty of moisture and lift across the area, so showers and isolated thunderstorms will be possible. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Unsettled weather continues still into the weekend with showers possible later Saturday into Sunday. For the first half of Saturday, our area will be in between one area of low pressure located offshore, and a second moving our of the Great Lakes region. As the low moves out of the Great Lakes region and approaches the Mid Atlantic later Saturday into Sunday, the potential for showers will increase across the area. A brief period of dry weather is expected later Sunday and Sunday night, and continuing into Monday as high pressure briefly builds to the south of the Mid Atlantic region. This dry weather will only be brief as chances will begin to increase Tuesday into Wednesday as a storm system approaches from the southwest. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas... Tonight...Mainly VFR with winds becoming light and variable. Thursday...Showers likely along with lowering cigs and visbys down at least MVFR at times. Winds generally east around 10 knots. Outlook... Thursday night-Saturday night...Sub-VFR conditions possible through the period with showers possible at times. Sunday...Sub-VFR conditions with showers, improving to VFR later in the day. Sunday night-Monday...VFR conditions expected. && .MARINE... Conditions will remain below Small Craft Advisory through Thursday. It will be quiet on the waters tonight but then expect more rounds of showers with some storms as well during the day Thursday as the next low approaches. East winds increase through the day to around 10-15 gusting to 20 knots by late day. Seas should generally be 2-4 feet. Outlook... Thursday night-Monday...Sub-Small Craft Advisory conditions are expected through the period, although winds may gust around 20 knots at times through the period, and seas may approach 4- 5 feet for a period on Friday. && .TIDES/COASTAL FLOODING... The new moon occurred Tuesday, May 7th, and this is resulting in high astronomical tides. An offshore wind today is lowering the surge some and some places may fall just short of advisory criteria for minor flooding tonight. Opted to keep the advisory as is given that several sites are forecast to reach minor flooding tonight and early Thursday morning. As a front settles to our south tonight, an onshore flow will develop and strengthen some through the end of the week. While the astronomical tides will be gradually lowering as we get farther away from the new moon, the onshore flow should boost the surge at least some. There is some guidance that shows moderate flooding at some coastal sites, however opted to keep it as minor given the uncertainty. The Coastal SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE... TIDES/COASTAL FLOODING... Flood Advisory for minor tidal flooding remains in effect for the Atlantic coastal zones, the Delaware Bay, and the tidal Delaware River with the high tide cycle tonight and early Thursday morning. Additional minor coastal flooding is forecast with the evening/overnight high tides through the end of the week. Flooding is not expected at this time for our Maryland zones along the Chesapeake. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...Coastal Flood Advisory from 1 AM to 6 AM EDT Thursday for PAZ070-071-106. NJ...Coastal Flood Advisory until 2 AM EDT Thursday for NJZ016. Coastal Flood Advisory until 2 AM EDT Thursday for NJZ012>014- 020>027. Coastal Flood Advisory from 1 AM to 6 AM EDT Thursday for NJZ017>019. DE...Coastal Flood Advisory until 2 AM EDT Thursday for DEZ001. Coastal Flood Advisory until 2 AM EDT Thursday for DEZ002>004. MD...None. MARINE...None. && $$ SYNOPSIS...Robertson NEAR TERM...MJL SHORT TERM...Robertson LONG TERM...Robertson AVIATION...MJL/Robertson/RCM MARINE...MJL/Robertson TIDES/COASTAL FLOODING...AKL/Gorse