Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/10/18


Area Forecast Discussion...UPDATED
National Weather Service Amarillo TX
740 PM CDT Sun Sep 9 2018 .UPDATE... TSTM line segment will likely remain in tact crossing the SW 3 COs. Upped POPs to 70 in WRN half of these COs with a fast taper east of there. Kept AMA in slt chc area for now, but did note the HRRR is showing the line extending to meet the ISO storms S of Dumas and it does show these clipping the city. Will watch this closely for additional updates. Storms in west have been near SVR levels with hail and wind being main threat, but no reports thus far. Very heavy rainfall is also occurring and some areas will pick up a quick 1/2 to 1 1/2" rainfall. && .AVIATION... Thunderstorms skated by DHT and expect they will do same at AMA but this will have to be watched closely. For now it is not mentioned in AMA TAF, but could happen between 2 and 4 UTC if the current line of storms extends further east. Outside of the threat for storms, no aviation concerns are advertised in next 24 hours, although there is a slight chance for brief IFR conditions around sunrise, especially where rains occur this evening. && .PREV DISCUSSION... /Issued 332 PM CDT Sun Sep 9 2018/ DISCUSSION... A shortwave will help aid in scattered storms off the NM mountains expected to move into the western Panhandles this evening and early tonight. Storms may be strong to isolated severe today as ML CAPE values around 1000-1500 J/kg and about 30kts effective shear. Don`t anticipate pops much east of the Amarillo, Dumas, Guymon line, and even those areas are under a slight chance. As pops clear out tonight, the story of the next several days will be dry and a warming trend. We will keep an eye on things Monday, as there might be another shortwave, but under northerly flow, it appears that any storms will be limited to the eastern NM area. But high pressure will begin to dominate for the work week, and overall temperatures will be on a rise so that by the end of the week most areas will be in the low 90s. Right now there is little indication that this high pressure will break down later in the week, or possibly into next week. Weber AVIATION... 18z TAF Cycle: VFR conditions have become dominant for KAMA and KDHT with KGUY following closely behind. Included tempo group for KGUY through 19z for MVFR cigs. Otherwise, clouds will continue to become more scattered through the afternoon. It does look like scattered thunderstorms will try to move out of northeast NM this evening, but there is some uncertainty with how far east the convection will make it before dissipating. Went ahead with a VCTS and prob30 group for KDHT, but feeling the VCTS may be a bit overdone. Storms should decrease in coverage considerably after 06z, and not expecting any impacts at KAMA or KGUY. Can`t rule out some areas of MVFR or even IFR cigs Monday morning, but confidence too low to include at this time. Patchy fog is also not out of question. Winds will generally be out of the south east through the evening at 10 to 15 knots, becoming south to southwesterly through Monday morning. Ward && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$ 88/88
Area Forecast Discussion
National Weather Service La Crosse WI
1100 PM CDT Sun Sep 9 2018 .SHORT TERM...(This evening through Monday) Issued at 302 PM CDT Sun Sep 9 2018 At 2 PM, high pressure provided sunny skies across the Upper Mississippi River Valley. Temperatures were around 70 degrees. Unlike the last couple of nights, the soundings are showing that there will be a deep (up to 4.5 km) layer of light winds along and east of the Mississippi River. The combination of these light winds and clear skies will result in the development of fog in the valleys, coulees, and cranberry bogs between 3 AM and 5 AM. Some of this fog will be dense. A Dense Fog Advisory may be needed. This fog will dissipate quickly between 9 AM and 10 AM. On Monday, a shortwave trough will move east across northern Minnesota. With the synoptic forcing remaining northwest of the area and the system moving into a dry air mass, the showers and storms will dissipate before reaching our area. With 925 mb temperatures being around 3C warmer, the high temperatures will top out in the lower to mid 70s. .LONG TERM...(Monday night through Sunday) Issued at 302 PM CDT Sun Sep 9 2018 On Tuesday and Tuesday night, a short wave trough will approach the area from the Northern Plains. However, as it approaches, the upper level ridge will be also retrograding. This will result in this trough remaining northwest and north of the area. As a result, the showers and storms will not make it into the region. From Wednesday through Friday, 925 mb temperatures will warm from 18C to 21C. As this occurs, the high temperatures will gradually warm from around 80 Wednesday to the lower and mid 80s by Friday. From Friday night into the weekend, a Canadian cold front will move southeast across the region. The timing of this system is uncertain due to the potential ridging ahead of Florence. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1100 PM CDT Sun Sep 9 2018 Cigs/WX/vsby: with clear skies and light sfc winds, concerns continue for river valley fog at KLSE. T/Td spread of 6 F at 03z...pretty good for a fog threat. Light east/southeast sfc wind also good to push fog off the Mississippi onto the airport. However, both the RAP and NAM12 bufkit soundings point to winds +10 kts just off the deck (by 300 ft) through the overnight hours, slackening toward 5 am. VAD wind profile for KARX also showing 15 kts of wind at 2 kft. Scenarios such as this usually result in fog within the valley, but more 300 ft stratus at KLSE. Going to start trending toward a higher threat for low stratus. Winds: light southeast tonight then south for Monday. && .HYDROLOGY... Issued at 302 PM CDT Sun Sep 9 2018 River flood warnings remain in effect for the Kickapoo and Trempealeau rivers. Levels are falling along both rivers. For specific information, see the latest flood statements for each of these rivers. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...Boyne LONG TERM...Boyne AVIATION...Rieck HYDROLOGY...Boyne
Area Forecast Discussion
National Weather Service Columbia SC
1022 PM EDT Sun Sep 9 2018 .SYNOPSIS... A weak cold front will stall across North Carolina. Expect a continued chance of mainly afternoon and evening thunderstorms next few days with near normal temperatures. Depending on the final track of Florence, our weather could be impacted during the late portions of the forecast period. && .NEAR TERM /UNTIL 7 AM MONDAY MORNING/... Radar indicating only a few lingering isolated showers near our northern forecast area (FA). Will expect this activity to dissipate in the near term. Other convective activity well to our W and NW associated with a frontal boundary and upper trough, appears will remain outside our FA as the front stalls. Otherwise, fair overnight. && .SHORT TERM /7 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... The area is still expected to remain in the warm sector ahead of a low pressure system Monday and Tuesday. A cold front will approach from the west, but will not cross the area. Southerly low-level flow will keep the air mass moist and unstable during this period, so precipitation chances will increase, with the best thunderstorm chances during the afternoons and evenings. Temperatures will remain above normal through this period with highs in the low to mid 90s and lows around 70. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... The big unknown through the longer term continues to be eventual track of Florence. Please refer to the NHC for the latest track and intensity guidance. Much uncertainty exists due to the unknowns surrounding the final track of the hurricane. Have kept a chance of convection each day per model consensus and latest WPC guidance. Expect temperatures to also be impacted by final track of Florence, all depending on cloud cover and potential rainfall. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... Convection winding down this evening. Some models indicated isolated convection continuing overnight...but coverage too low to include in TAFs. Expect VFR through at least 06Z. Fog threat appears low with possible low level jet and some cloudiness. Lamp and HRRR suggest low threat. Will include fog/stratus 07Z-13Z at AGS and OGB based on persistence. High resolution models indicated showers and thunderstorms developing Monday afternoon. Still expect primarily VFR conditions. Have included VCSH all TAF sites during the afternoon. EXTENDED AVIATION OUTLOOK...Continued low-level moisture will keep the potential for early morning fog/stratus. Restrictions are possible in scattered afternoon/evening showers and thunderstorms. Any potential impacts from Florence will not be in the area until around Thursday. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1011 PM CDT Sun Sep 9 2018 .UPDATE... The main update to the forecast is to reduce PoPs from Austin to San Marcos eastwards to La Grange and Giddings. High resolution models focus the heaviest rainfall tonight across Zavala, Frio, and Dimmit Counties where moderate to heavy rainfall is already ongoing between Batesville and Pearsall. While most of the area will only see a 1/2 to maybe inch of rainfall from some isolated showers and storms through the night there are still indications from the HRRR and other high resolution models that localized totals of around 3 to 4 inches are possible, especially in the southwestern portions of the Rio Grande Plains. The rest of the forecast is on track, but have retrended all of the hourly weather grids. && .PREV DISCUSSION... /ISSUED 707 PM CDT Sun Sep 9 2018/ AVIATION... /00Z TAFS/ Intermittent mostly light showers will remain possible for much of the period for SAT/SSF with AUS expected to see activity mainly in the afternoon and early evening. More stable conditions are expected at DRT through the period. Evening cigs should ease into mvfr levels with some ifr conditions expected after midnight. Steady NE breezes should limit fog development somewhat overnight. A few heavy downpours and thunder will be possible later tonight mainly affecting SAT/SSF as a shortwave disturbance moves across. Coverage may not be enough to warrant mention in the TAFs as the better forcing looks to pass to the south. Convection should become more isolated diurnal Monday. Monday evening should see a return of mvfr cigs around SAT/SSF and possibly AUS. PREV DISCUSSION... /ISSUED 400 PM CDT Sun Sep 9 2018/ SHORT TERM (Tonight through Monday Night)... Overall shower activity has decreased across the area this afternoon. However, another round of moderate to heavy rain is possible this evening into Monday as an upper level disturbance pushes across the area. With the upper level support, the rich tropical moisture in place and a frontal boundary that sits over the Coastal Plains combined are good ingredients for additional one half to one inch with isolated 3 to 5 inches of rainfall especially across the southern part of the Rio Grande. With that said, the Flash Flood Watch has been extended through Monday morning for the southern part of Rio Grande and areas along Interstate 35. The Flash Flood Watch earlier issued for the far southeast county of South Central Texas has been cancelled. Heavy rain is not expected to have a big impact across the far southeast counties of South Central Texas through this evening. As the upper level disturbance moves to the southeast and into the eastern portion of Texas, showers and thunderstorms are likely to concentrate across the Coastal Plains Monday afternoon and evening. LONG TERM (Tuesday through Sunday)... Scattered showers and isolated thunderstorms will persist across the Coastal Plains and areas along and east of Interstate 35 through next weekend as several upper disturbances move across the area and a weak frontal boundary remains across the Coastal Plains. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 79 69 83 70 86 / 80 40 40 30 40 Austin Bergstrom Intl Airport 78 70 80 69 86 / 80 40 50 30 50 New Braunfels Muni Airport 84 70 84 70 87 / 90 50 50 30 60 Burnet Muni Airport 76 67 82 68 83 / 80 20 20 20 30 Del Rio Intl Airport 82 69 88 69 88 / 60 20 10 10 10 Georgetown Muni Airport 76 68 80 68 85 / 80 30 30 30 40 Hondo Muni Airport 79 70 86 70 87 / 80 50 40 20 30 San Marcos Muni Airport 80 70 80 70 86 / 80 50 50 30 50 La Grange - Fayette Regional 81 71 82 71 87 / 80 50 80 50 70 San Antonio Intl Airport 82 70 84 70 86 / 90 60 50 30 40 Stinson Muni Airport 87 72 85 72 87 / 90 60 50 30 50 && .EWX WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch until 9 AM CDT Monday for Atascosa-Bandera- Bastrop-Bexar-Blanco-Caldwell-Comal-Dimmit-Frio-Guadalupe-Hays- Kendall-Kinney-Lee-Maverick-Medina-Real-Travis-Uvalde-Williamson- Wilson-Zavala. && $$ Mesoscale/Aviation...Oaks Synoptic/Grids...Treadway
Area Forecast Discussion...UPDATED
National Weather Service Grand Forks ND
1046 PM CDT Sun Sep 9 2018 .UPDATE... Issued at 1046 PM CDT Sun Sep 9 2018 Updated aviation discussion for 06z TAF issuance. UPDATE Issued at 932 PM CDT Sun Sep 9 2018 Updated rain chances to reflect latest radar returns. The previously mentioned line of storms in the southern valley has weakened considerably after sunset. Suspect to still see isolated storms amidst shower activity overnight, but severe threat has ceased. The final area of showers along the front has moved into northeast and central ND and will work through the area eastward overnight. UPDATE Issued at 652 PM CDT Sun Sep 9 2018 Increased rain chances for southern valley due to formation of line of storms from Jamestown ND to Mobridge SD, just ahead of the approaching cold front. Areas in the northern valley have not had capping break early this evening due to persistent cloud cover, and with sunlight waning, expect weaker activity to be the trend for areas north of Highway 2 this evening. In southern ND, a broken line of storms with some stronger and perhaps a few severe is poised to move eastward through this evening. && .SHORT TERM...(This afternoon through Monday) Issued at 344 PM CDT Sun Sep 9 2018 Mid level shortwave trough is beginning to build towards southeast Saskatchewan and southwest Manitoba. As the surface a warm front current sits near the Red River Valley, while a cold front has set up over western ND. Clearing skies with steep mid level lapse rates has supported 1000-3000 J/KG of ML CAPE according to current RAP analysis over central ND, while better deep layer shear is offset to the northwest of our CWA closer to surface cold front and surface low. CINh has decreased, so as front begins to push east this afternoon and forcing increases we should see showers/thunderstorms begin to develop first near the Devils Lake area, then over spread eastern ND through the evening, and eventually push across northwest MN through early Monday morning. Better lift will tend to be across our north closer to mid level trough, but frontogensis is still advertised to support activity even into our south (though coverage may not be as great). Regarding severe threat: The instability axis will make it as far east as the Red River Valley and with increasing shear along frontal zone. This should support a few strong or severe storms within larger shower/thunderstorms clusters through the evening weakening further east as instability begins to drop off overnight (towards the south and southwest). Threats should be on lower end of severe criteria (1 inch hail, 60 mph wind) though if higher instability/shear values were to occur larger hail threat may be possible. All shower/thunderstorm activity should exit our CWA to the east around sunrise Monday as surface high pressure brings dry westerly flow behind the cold front. While there may be a slight decrease in temps aloft behind the cold front Monday morning, temps recover by the afternoon under clear skies. Lows may be mild to to cloud cover/precip and only weak CAA, and highs Monday should be similar as today (generally in the 70s/near 80F). .LONG TERM...(Monday night through Sunday) Issued at 344 PM CDT Sun Sep 9 2018 A more SW flow aloft will set up, increasing temperatures and taking storm track farther to the north. The first of several shortwaves looks to move through late Tue, dragging a cold front through while increasing thunderstorm chances Tue afternoon night. The frontal passage will usher in some cooler temps for Wed. The active pattern will continue into the end of the week as a quasi stationary surface boundary interacts with additional shortwaves to instigate sporadic chances for pcpn. Confidence in exact timing and specifics of convection strength is low, but overall a wetter and closer to average temp regime will be setting up for the region. Warmest day will be Tue ahead of the surface front, with highs in the 80s, before falling back into the 70s and then 60s as the week ends. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1046 PM CDT Sun Sep 9 2018 Scattered showers and storms will develop along a cold front moving through from west to east tonight. Ahead of this activity, expect low VFR cigs and gusty south winds. Sites in the vicinity of showers and storms will see MVFR or IFR cigs and vsbys, affecting sites along and east of the Red River Valley overnight and into early Monday morning. MVFR to IFR stratus may linger for the BDE to BJI to PKD and eastward into the early to mid morning Monday. Behind the front, sites will see VFR conditions and winds will shift to the west and northwest, becoming light as high pressure moves in on Monday. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...BP SHORT TERM...DJR LONG TERM...WJB AVIATION...BP
Area Forecast Discussion
National Weather Service Fort Worth TX
917 PM CDT Sun Sep 9 2018 .UPDATE... A stationary front remains along the Texas Coast this evening, with postfrontal stratus remaining over much of North and Central Texas. The GOES-16 10.3-3.9 micron "night fog/stratus" product shows a dense shield of stratus draped across most of our county warning area. Surface observations show that this stratus is holding strong with mostly cloudy to cloudy skies being reported at most sites. Guidance indicates that mostly cloudy to cloudy skies should remain through the night, thus sky cover was bumped up a bit for the overnight grids. Concerning PoPs in our southeastern counties, radar does not show any echoes currently, but the HRRR and NAM both continue to suggest the development of a few showers tonight along and south of a Killeen to Palestine line as some subtle isentropic ascent continues near the 700 mb cold front. PoPs were nudged down ever so slightly, but remain in the chance category. Besides that, morning lows should range from the lower 60s across our northwestern counties to near 70 across our southeastern counties. Winds will be light (5-10 MPH) and from the north to northeast. Godwin && .AVIATION... /Issued 725 PM CDT Sun Sep 9 2018/ /00Z TAFs/ As a cold front stalls along the Upper Texas Coast, the shallow postfrontal layer across North and Central Texas will struggle to deepen. As a result, ceilings will persist between FL020-035. Deeper northerly flow west of the TRACON will encourage clearing, but any scattering along the I-35 corridor will be brief. With minimal low-level dry advection, ceilings will have difficulty staying above FL030 tonight. And as the boundary layer cools overnight (aided by additional cold advection), ceilings should eventually fall. Bases below FL020 would be more likely to occur Waco, but a TEMPO for lower ceilings may be needed at the Metroplex TAF sites with the 06Z package. The frontal inversion will persist on Monday, and veering winds to the northeast will discourage ceilings from lifting or scattering. VFR should still take hold during the afternoon though Waco may have more difficulty accomplishing this. Surface winds will attempt to become southeasterly Monday night into Tuesday morning, but easterly or northeasterly flow should persist on Tuesday. 25 && .SHORT TERM... /Issued 256 PM CDT Sun Sep 9 2018/ /Rest of Today and Tonight/ The stalled boundary south of our region will continue to be the focus for light rain showers and misty conditions for areas south of a Waco to Palestine line through the rest of the afternoon. As the main trough axis moves east of North and Central Texas, the boundary will rebound northward tonight, but likely remain across our Central Texas counties. This boundary, as well as a weak disturbance sliding up the Texas Coast, will likely become the focus for additional scattered showers and isolated storms across our far southern counties overnight. In the meantime, dry air will be working its way from the north, leading to a partial clearing north of Interstate 20 and west of Interstate 35. At this point it appears as if there will not be enough clearing for significant radiational cooling, precluding the formation of fog. The best chance for patchy fog will likely remain north of the Red River. Low temperatures will be the coolest across the northwestern counties, where clouds are likely to scatter earlier in the night. Low 60s can be expected in those areas. For areas that remain mostly cloudy to cloudy, mid 60s to around 70 degrees are expected. Hernandez && .LONG TERM... /Issued 256 PM CDT Sun Sep 9 2018/ /Monday through the Weekend/ The upper level trough responsible for the swath of precipitation across South Central and Southeast Texas will remain nearly stationary for the first half of the week, providing a source for continued rain chances across the southeastern third to half of the region. The highest coverage and best rain chances will remain south of the forecast area through mid week, along with the better chances of locally heavy rain and additional flooding. Weak mid level lapse rates will keep thunderstorms at a minimum and the latest forecasts will only mention isolated thunder through Tuesday. Slight chance POPs will extend as far north as the Interstate 20 corridor tomorrow and Tuesday, and then to the Red River on Wednesday as Gulf moisture gets nudged a little farther north. With the cold front nestled over southeast Texas, temperatures across North and Central Texas will be slightly below normal for the next few days with lows in the 60s and highs in the lower 80s. Surface winds behind the front will remain out of the north through Monday, veer to the east by Tuesday and return to the southeast on Wednesday as an upper low digs across the West Coast. Not only will this expand the rain chances a little farther north, but temperatures will also return to near or slightly above normal values starting Wednesday. Scattered showers and thunderstorms will be possible Thursday and Friday as a weak upper trough moves from east to west from the western Gulf across Texas. A few of these storms may produce brief heavy rain, but neither severe weather nor widespread flooding is expected based on the forecast environment. Moisture will remain in place next weekend, keeping the warm and humid weather going Saturday and next Sunday. Rain chances will dwindle, however, as we move through the weekend, due to subsidence caused by a strengthening mid level ridge over the Plains. The focus will shift back to the tropics as multiple systems work their way west across the Atlantic, and another disturbance develops across th eastern Caribbean. We will keep an eye on activity in the Caribbean, but at this time we do not see any significant threats to the Gulf of Mexico. 30 && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 67 82 68 83 70 / 0 5 10 20 10 Waco 69 81 68 82 68 / 10 20 20 30 20 Paris 67 80 64 82 67 / 5 10 10 20 10 Denton 64 82 66 83 67 / 0 5 5 10 10 McKinney 65 82 65 83 68 / 0 5 10 20 10 Dallas 69 82 68 83 70 / 5 5 10 20 10 Terrell 68 81 67 82 69 / 5 10 20 30 20 Corsicana 70 80 68 81 69 / 10 30 30 30 20 Temple 68 81 68 82 68 / 20 30 20 30 20 Mineral Wells 64 82 66 82 66 / 0 5 5 10 5 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 37/25
Area Forecast Discussion
National Weather Service Wilmington NC
836 PM EDT Sun Sep 9 2018 .SYNOPSIS... High pressure across the northwestern Atlantic will maintain a warm and humid tropical airmass across the Carolinas. This high will also help steer what is expected to become a very strong Hurricane Florence toward the Carolina coastline Thursday into Friday. Depending on what path the hurricane takes, significant impacts from strong winds, heavy rainfall, and storm surge flooding may develop. && .NEAR TERM /THROUGH MONDAY/... As of 700 PM Sunday...Convection lingering across Darlington and Marlboro has prompted a flood advisory, but elsewhere across the area, convection has come to an end for now. The latest HRRR shows convection over the land dying out this evening and nocturnal activity over the waters developing after midnight with some shwrs making it on shore overnight into Mon morning. Southerly flow will continue around high pressure building back in over the area overnight. High pressure will continue on Monday with light winds and only meso- scale forcing. Shower and thunderstorm activity is expected to be in the widely scattered to scattered range along the sea-breeze and inland. With the swell from Florence moving into the area will again go with a high risk of rip currents. A coastal flood advisory remains in effect for downtown Wilmington and points along the Cape Fear River from 9 PM to 11 pm. This will cause minor flooding at the battleship and along downtown && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... As of 3 PM Sunday...Building mid-level ridging offshore from the Mid-Atlantic states will dominate this period as it extends southwest to the Southeast U.S. States. This will prevent a sfc cold front from dropping into the ILM CWA in fact models stall it NW thru N of the ILM CWA by the end of this period. With a tropical airmass in place, expect showers and thunderstorms to occur thruout this period, with the hier POPs slated for Tue midday thru early evening. During the overnight periods of Mon and Tue nights, nocturnal convection from off the Atlantic waters will be possible. Pops have been geared to a hier chance along the immediate coast then inland. The subsidence well ahead of Hurricane Florence may reach the ILM CWA by or after Wed daybreak. Have indicated a subsiding trend to POPs leading up to Wed daybreak. The diurnal range in temperatures will run 20 to 25 degrees except around 15 degrees along the immediate coast. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... As of 3 PM Sunday...Most significant event during the period will occur during the Wed-Fri time range as Hurricane Florence approaches the southeast. Still a lot to resolve with respect to the exact track, but it seems more and more likely that major impacts from the storm will occur in the ILM forecast area. As the storm moves onshore a ridge begins to build over the OH/TN valleys, causing Florence to slow to a crawl. Cloud cover and rain will linger over the Carolinas and Virginia through the weekend. Rainfall amounts will depend largely on where the storm makes landfall. The bulk of the heavy rain and flooding from the rapidly slowing storm will occur north of the center. Temperatures near normal at the start of the period will dip below normal during the day with the storm lingering in the region. Lows will run above climo due to cloud cover and low level moisture. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... As of 00Z...Convection inland should die out by 01Z. Models again show some inland fog after 08Z. Think we will stay just above IFR, but brief IFR conditions are possible, particularly inland. Monday, same as it has been with a light gradient and scattered convection along the resultant by noon. Extended Outlook...Mostly VFR through Wednesday with the exception of isolated showers or t-storms. Patchy early morning MVFR fog is also possible. Hurricane Florence may begin to affect the area Thursday with strengthening winds and deteriorating ceiling/visibility and continuing into Friday. && .MARINE... NEAR TERM /THROUGH MONDAY/... As of 800 PM Sunday...Winds are expected to be south to southeast at 5 to 10 knots through tomorrow. Seas will run 2 to 3 feet with a 1 foot southeast swell. Showers and a few thunderstorms are expected to redevelop over the waters tonight and along the land breeze at sunrise on Monday. Winds and seas may be higher in showers and tstms. SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... As of 3 PM Sunday...Weak ridging will influence the winds during this time period. Along with the weak ridging will be a relaxed sfc pg. Will identify a dominant wind direction for the 2 periods, Mon night and Tue. For Tue night, all waters will become Easterly with speeds around 10 kt. Significant seas will be governed by the 2 to 3 foot forerunner 11 to 13 second period swells from Florence. Seas are fcst to increase to around 4 ft late Tue night. This the result of a 13 to 15 second period swell or wave-train, associated with Florence. LONG TERM /WEDNESDAY THROUGH FRIDAY/... As of 3 PM Sunday...Treacherous marine conditions expected through the duration of the period. Hurricane Florence will be approaching from the southeast as the period begins. Tropical storm force winds could reach the waters as early as Wed evening with seas rapidly approaching 10 ft late in the day. On the current forecast path the worst conditions would be late Thu and Thu night, as the storm crosses the waters and moves onshore. Conditions will remain treacherous on Fri with the storm expected to slow down around the time of landfall and linger in the region into the weekend. Headlines are expected through the duration of the period. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...High Rip Current Risk until 8 PM EDT this evening for SCZ054- 056. NC...High Rip Current Risk until 8 PM EDT this evening for NCZ106- 108-110. Coastal Flood Advisory from 9 PM this evening to midnight EDT tonight for NCZ107. MARINE...None. && $$ NEAR TERM...RGZ/RH SHORT TERM...DCH LONG TERM...III AVIATION...RH
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1026 PM EDT Sun Sep 9 2018 .UPDATE... Issued at 1026 PM EDT SUN SEP 9 2018 Based on current trends in radar and the HRRR model, decided to greatly lower precipitation chances for the rest of tonight. Will be going will 20 to 50 percent chance of showers as thunder has long since ended across the area and it looks like no more will occur. The hazardous weather outlook was also updated to remove thunder for tonight. The forecast update has already been sent out. UPDATE Issued at 820 PM EDT SUN SEP 9 2018 The flash flood watch was allowed to expire at 8pm this evening. Therefore, the hazardous weather outlook and zone forecast text products were both updated to reflect the expiration. Also used the latest obs to freshen up the hourly forecast grids. Will continue to monitor current trends in radar imagery and model data and will update the forecast again if necessary by the end of the shift. && .SHORT TERM...(This evening through Monday night) Issued at 322 PM EDT SUN SEP 9 2018 Upper level low pressure near the southern end of lake Michigan continues to pull slowly NNE. At the surface low pressure centered northeast of Lexington continues to very slowly move northeast. A trailing cold front extends southwest to just west of Bowling Green. With the very slow movement of the upper and surface systems, the cold front will be slow to move across eastern KY. There is good model agreement that the front will be near the VA border at 12Z Monday, and then push on southeast before stalling out along the Appalachians. With ongoing flood and flash flood warnings in the area we will continue the flash flood watch, which is in effect until 8 PM. Heavier rains will shift southeast of the areas that have already been hard hit, and convection will decrease in intensity this evening. The southeast part of the area has not experienced repeated heavy rains like the northwest and flash flood guidance is higher there. So even though showers and storms will continue beyond 8 PM the threat for new flash flooding will end. However some flood warnings may need to be extended in the northwest for ongoing flooding that will continue well after the rain ends. With the front stalling just to the southeast of our area along the Appalachians, we will see much cooler air spread into eastern KY for a couple of days. Highs on Monday will only be in the upper 60s to lower 70s and lows Monday night will be in the upper 50s to lower 60s. Rain will end late tonight into early Monday from northwest to southeast, but a few showers may linger in the southeast into Monday night. .LONG TERM...(Tuesday through Sunday) Issued at 322 PM EDT SUN SEP 9 2018 The cold front which will move southeast of the area on Monday will stall along the Appalachians, but will meander back into the area by mid week. There is excellent model agreement that a sprawling area of upper level high pressure north of Bermuda will build west as the week progresses. With rising heights and the surface front moving back into the area, we`ll see temperatures return to well above normal readings, with above normal temperatures continuing into next weekend. With increasing temperatures and moisture, and the already mentioned front moving back into the area, the threat for afternoon and evening thunderstorms will return by midweek, and continue into the weekend. The main focus for many folks during the coming week will of course be the path of Hurricane Florence. The hurricane will track west or west-northwest on the south side of the upper high, before nearing or moving onshore somewhere over the southeast to mid Atlantic coast. There is tremendous uncertainty of the path of the hurricane, with the ECMWF still having an extreme western solution into western VA and the latest GFS run indicating the hurricane may not even make land fall. For our area it is important to note that even with the western solution of the ECMWF any significant impacts and heavy rain will remain east of eastern KY, mainly on the east side of the Appalachians. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) ISSUED AT 725 PM EDT SUN SEP 9 2018 Numerous showers, and few storms, will continue to move across eastern Kentucky this evening and tonight. Expect restrictions at all TAF sites, mainly in the form of low CIGS between 300 and 800 feet. Locally heavy rainfall will remain a threat for a while tonight, but should steadily diminish as a cold front moves across the area. The rain should finally stop directly affecting the TAF sites between 12 and 15Z on Monday. Conditions will be slow to improve on Monday, as moist air and low level clouds remain in place behind a departing cold front. We can expect IFR to LIFR conditions tonight, and MVFR to IFR conditions on Monday. Winds will shift to the west at around 5 mph during the day on Monday across the area. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AR SHORT TERM...SBH LONG TERM...SBH AVIATION...AR
Area Forecast Discussion
National Weather Service Marquette MI
711 PM EDT Sun Sep 9 2018 .SHORT TERM...(This evening through Monday) Issued at 337 PM EDT SUN SEP 9 2018 Another quiet short term period is expected. Water vapor imagery and RAP analysis show a pair of shortwaves tracking ene toward southern Hudson Bay, one over ne Manitoba and a second over southern Saskatchewan/sw Manitoba. Cold front associated with these waves extends from ne Manitoba to the central Dakotas. Mid-level ridge over northern Ontario into the Upper Mississippi Valley is supporting sfc high pres over southern Quebec with ridging extending back across the Upper Great Lakes/Upper Mississippi Valley. Similar to yesterday, nighttime/morning flow off the Great Lakes led to expansion of cu/stratocu downwind of the Lakes after sufficient heating occurred late morning. These clouds have since almost completely dissipated as low-level moisture is mixing out. Tonight, fcst area remains under an axis of min precipitable water around one-third of an inch, similar to last night. With sfc high pres over southern Quebec continuing to ridge back to the Upper Lakes, low-level wind speeds viewed at 950mb will be similar to or lighter than last night over much of the area. As a result, favored the low side of guidance for low temps, utilizing mostly the bias corrected CMC global which is normally a superior performer on radiational cooling nights. Expect some mid 30s at the traditional cold spots in the interior central and eastern fcst area, and will include a mention of patchy frost. Could be some patchy/shallow fog as well over the s central, mainly low areas and around lakes/rivers/swampy areas. To the w, approaching cold front associated with the aforementioned shortwaves will move closer, resulting in a tightening of the pres gradient/stronger low-level winds over far western Upper MI. With sfc winds stirring, low temps should be at least a few degrees higher than last night at most locations over the far w. On Mon, the second of the 2 shortwaves previously mentioned will move across northern Ontario. Weakening low-level jet/moisture transport and low-level convergence suggest shra that will be ongoing early Mon morning across northern MN will likely dissipate as they continue eastward. Some of the shra may survive to reach far western Lake Superior, but that should be it. Otherwise, expect another mostly sunny day. Once again, there may be an expansion of cu/stratocu in the s to se flow off Lake MI during the morning, but warmer air at 850mb compared to this morning suggests coverage will be less than recent mornings. In general, high temps should be a few degrees higher than today at most locations. .LONG TERM...(Monday night through Sunday) Issued at 251 PM EDT SUN SEP 9 2018 Models indicate that mid/upper level ridging will dominate the northern Great Lakes through much of the upcoming work week keeping conditions dry. A trough deepening near the West Coast later by midweek will maintain a downstream ridge across much of the central and eastern CONUS. A strengthening sw flow between these features into the Upper Great Lakes will allow for a warming trend. Frontal boundaries approaching from the west will generally remain north and west of the region which should limit shower/t-storm chances for Upper Michigan through much of the work week. A series of stronger shortwaves emerging from the Northern Rockies/Northern Plains by the weekend will work to flatten the mid-upper level ridge and bring a frontal boundary into the Northern Great Lakes increasing the chance of showers/t-storms over Upper Mi. Mon night-Tue, A weakening shortwave and its associated forcing will slide to the north of Lake Superior Mon, and although model soundings do show some increase in low-level moisture into the western U.P. Mon night/Tue morning, given weak forcing not expecting much in way of pcpn. Weak ridging over the rest of the fcst area will maintain mostly dry conditions into Tue, although increasing dew points into the upper 50s/lower 60s will make it much more humid as Tue high temps climb into the mid to upper 70s. Tue night into Wed, A stronger shortwave moving through northern Ontario will help push a frontal boundary toward the arrowhead of MN as a warm front moves across Upper Mi. The close proximity of this frontal boundary and the hint of some weaker shortwaves moving along the boundary could trigger some showers/t-storms as models indicate MUCAPE values at or above 1000j/kg. Gut feeling is that most of the convection would stay out over western/north central Lake Superior closer to the frontal boundary, but a few showers/isold storms could sneak into far western U.P. Tightening sw gradient and increased mixing from low-level winds will keep min temps up Tue night around 60F across much of the area especially for downsloping locations along Lake Superior. Continued southerly flow and mixing of 850 temps near 18C to sfc should yield high temps in the upper 70s/lower 80s across much of the area. Wed night into Fri, Models advertise amplifying ridge and rising 5H heights across the Upper Great Lakes region in response to trough digging into the Pacific NW Coast. At this same time, Hurricane Florence is expected to slam into the mid-Atlantic Coast sometime Thu and could remain nearly stationary providing a major flooding threat for that region of the CONUS into next weekend. The amplified ridging over our area will result in quiet, dry conditions and continued above normal temps through much of this period. 850 mb temps remaining near 18C should again result in high temps Thu and Fri in the upper 70s and lower 80s for most locations. Min temps Wed night and Thu night will generally be in the upper 50s to lower 60s. Fri night into Sun, Models then show mid-upper flow flattening out again toward next weekend as a series of strong shortwaves emerge out the Northern Rockies and Northern Plains and move east across the northern CONUS. This will allow for a cold frontal boundary to sag into Upper Michigan with increasing chances for showers/t-storms Fri into Saturday. PWATs surging toward 2 inches ahead of the front with dew points into mid 60s would indicate the potential for heavy rain with the storms that develop. Depending on timing of front the pattern could also result in some risk of strong to severe storms with increasing deep layer shear to 40-50 knots and building instability with MLCAPE values to 1000-1500 j/kg. Both the GFS and ECMWF indicate a sfc high pres ridge building into the area behind the front for Sun which would usher in cooler and drier conditions for the end of next weekend. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 707 PM EDT SUN SEP 9 2018 For this TAF issuance, fog/low-level stratus potential continues to look low for the terminals. Other than upper-level clouds cruising overhead through the period, and an afternoon CU field developing tomorrow, look for VFR conditions to prevail. S to SE winds overnight will remain elevated at KIWD and KCMX as the pressure gradient tightens over the region, and become more S-SW on Monday. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 337 PM EDT SUN SEP 9 2018 With a cold front to the nw and a high pres ridge just se of Lake Superior, se to s winds on Lake Superior will gust to around 20kt tonight. Weakening pres gradient on Mon will allow wind gusts to fall back to around 15kt during the day. Winds will then remain under 20kt into Tue. Another approaching cold front will result in stronger winds of 15-25kt Tue night into Wed morning. Winds will then diminish to under 15kt during Wed as the cold front weakens and fails to reach Lake Superior. Expect somewhat stronger winds again for Thu/Fri (gusts to around 20kt) as a pair of low pres waves lift from the Plains to northern Ontario. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...Voss AVIATION...lg MARINE...Rolfson
Area Forecast Discussion
National Weather Service Missoula MT
247 PM MDT Sun Sep 9 2018 .DISCUSSION...It continues to be a very nice early September day across the Northern Rockies with temperatures warming into the 70s to low 80s. Expect temperatures to cool tonight down into the 40s in the valleys and potentially in the upper 30s for portions of the Flathead, Missoula and Bitterroot Valleys. It should be cool night in the high valleys across southwest Montana as temperatures fall into the 30s. Not much change to the forecast for Monday. Still anticipating a cold front to traverse through the region causing gusty winds to develop with a chance for showers over northwest Montana. Area lakes will be breezy, generally between 10 and 20 mph, but not expecting lake wind advisory criteria at this time. For the most part, it will be a nice day for most areas except maybe in the higher elevations of Glacier National Park where strong gusty winds combined with temperatures in the 50s with passing showers could be a little chilly. A trough is still expected to remain over the Pacific Northwest for Wednesday through the rest of the week. This will allow for temperatures to remain at or below normal for this time of the year. Also, forecast models have been trending slightly wetter with the overall pattern, especially for north-central Idaho and northwest Montana. Given the trends in the forecast models, we did increase the chances for precipitation in those locations mentioned above. Elsewhere across the Northern Rockies, precipitation is expected to be more showery, but slight increases for chances in rain were made to the forecast as well. && .AVIATION...Expect typical afternoon winds and favorable flying conditions for the remainder of this Sunday afternoon and evening. The HRRR smoke forecast does show the potential for smoke near fires today, otherwise impact should remain limited. A front will move through Monday and will cause gusty westerly winds between 20 and 30 knots between 10/1800Z and 11/0300z. There could be a few showers or perhaps an isolated thunderstorm near the Canadian Border. Winds could gust near 40 knots near ridge-top over Glacier National Park. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...&& $$
Area Forecast Discussion
National Weather Service Raleigh NC
1045 PM EDT Sun Sep 9 2018 .SYNOPSIS... A cold front will sink southward across central NC, before stalling across south portions of the area early Monday morning. The front is expected to lift back to the north as a warm front on Monday. In the wake of the front, a warm and humid air mass will be in place through mid week with a chance of showers and thunderstorms each day. Based on the official NHC forecast, portions of the Carolinas can expect significant impacts from Tropical Cyclone Florence late this week. && .NEAR TERM /THROUGH TONIGHT/... As of 1045 PM Sunday... A broken band of scattered showers and storms from the SE Piedmont across the Sandhills and just S of the Triangle and Wilson should continue a slow drift to the N over the next several hours, in line with recent HRRR runs. One storm intensified as it approached the stationary CAD front and locally higher low level shear, exhibiting deep but broad rotation and bringing 50+ mph winds near Pinehurst. These storms have formed in a narrow band of ~1500 J/kg MLCAPE and beneath weak upper divergence. Will need to watch this activity carefully over the next few hours as they shift into the zone of enhanced low level vorticity and around 20 kts of effective deep layer shear. Otherwise, weak overrunning atop the stable pool covering much of the Piedmont will bring a threat of a few sprinkles or showers overnight, so after a few hours of an isolated storm threat (with quick spinup potential) in the vicinity of the boundary, will maintain a low chance pop across the NW half of the CWA later tonight. Climatology for such CAD events, along with high res guidance, supports stratus holding firm and even expanding areally overnight through Mon morning, with continued areas of fog becoming more dense in spots as we approach daybreak, primarily over the N and W CWA. Expect lows in the lower 60s NW ranging to the lower 70s SE. -GIH Earlier discussion from 357 PM: Given the shallowness of this CAD layer, daytime heating should be fairly efficient at mixing out the wedge from SE to NW across most, if not all of the forecast area by the mid to late afternoon. The resultant differential heating from the SE to NW erosion of the CAD regime, in concert with weak sfc frontal-convergence will support the re-development of scattered showers and thunderstorms across the area through the afternoon and evening. It does appear slightly drier aloft/lower PWATS advecting into the area from the south will limit overall coverage. Rain chances will gradually fade with loss of heating, with the best chance for showers to linger the longest across the NW Piedmont where moist upglide along the lingering wedge/quasi-stationary front will support the best lift. Fcst soundings suggest stratus will re-develop late this evening and spread south overnight, encompassing all of central NC. Additionally, areas of fog, possibly dense in a few spots is also possible. Overnight lows in the mid/upper 60s NW to lower/mid 70s SE. && SHORT TERM /MONDAY AND MONDAY NIGHT/... As of 357 PM Sunday... Deep southwesterly flow between the mid/upper level ridge off the western Atlantic and an upper level trough shearing out over the Ohio Valley/Great Lakes region will keep moist 1.75-2.0" PWAT air in place. After the morning stratus and lingering damming airmass in place across the NW Piedmont mixes out through the morning and early afternoon hours, daytime heating and resultant moderate destablization within the moist airmass will support the development of scattered convection across central NC. Greatest coverage will mostly likely be driven by mesoscale boundaries/forcing; 1)in proximity to the NW Piedmont where the later erosion of the wedge will most likely set-up a zone of differential heating; 2)Across the coastal plain, where the interaction of sea-breeze will be most influential. Expect convection to die off after sunset. Highs ranging from lower/mid 80s NW to lower 90s SE. Overnight lows 70 to 75. && .LONG TERM /TUESDAY THROUGH SUNDAY/... As of 358 PM Sunday... Tuesday through Wednesday Night: A sfc cold front is progged to be just on our western periphery on Tuesday, with a series of weak disturbances expected to push from southwest to northeast through the Carolinas through the middle of the week. This will allow, at minimum, diurnal enhancement of shower/storm activity each afternoon and evening, especially with an airmass characterized by high PWs and moderate instability remaining in place. Afternoon high temperatures will remain slightly above normal, topping out in the mid to upper-80s (north) with low 90s across the South. Low temps during this time are expected to generally be in the lower 70s. Wednesday night through Saturday: The forecast becomes murky mid/late week with the approach of what is now Hurricane Florence. The mid/upper level ridge strength and position will play a key role in determining the actual track of the storm, with the trend in the guidance to a more left/westward track (vs re-curving). Such a trend is a cause for concern for us here in central North Carolina, which remains in the direct path of the NHC forecast track, with a landfall expected by pre-dawn on Friday near the NC/SC state line. If this trend in the forecast continues and holds true, potentially life threatening impacts in the form of damaging winds, flooding rains, and potentially even some weak and short-lived tornadoes will be possible. It remains a bit too early to start nailing down specifics, however, as even the slightest shifts in the ultimate track, intensity, and size of the storm could cause wild fluctuations in said impacts. Even so, residents of central NC are strongly encouraged to closely monitor the latest forecasts and to ensure everyone has emergency kits and a hurricane plan in place. Don`t forget about making plans for your pets too! It is never too early to prepare! For more tropical information, visit our new Tropical website at www.weather.gov/rah/tropical. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... As of 840 PM Sunday... 24 hour TAF period: IFR to LIFR cigs are expected to develop behind a southward sinking cold front this evening into the overnight, with the front becoming stationary around KFAY (where more in the way of MVFR/IFR conditions are expected late tonight into Monday morning. Cigs should lift from south/southeast to northwest on Monday from around 15Z to 21Z, with the potential for afternoon/evening showers and storms. Looking ahead: Mainly afternoon thunderstorms with early morning sub- VFR stratus will then be possible through the remainder of the extended. Based on the latest official NHC forecast, adverse aviation impacts could occur as early as Wednesday night and continue through Friday. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...BSD/CBL/Haines/Hartfield NEAR TERM...Hartfield/CBL SHORT TERM...CBL LONG TERM...JJM AVIATION...BSD/CBL
Area Forecast Discussion
National Weather Service San Angelo TX
700 PM CDT Sun Sep 9 2018 .AVIATION... /00Z TAFS/ Currently seeing VFR conditions across the terminals early this evening but low stratus is expected to develop mainly after midnight, with MVFR ceilings affecting the terminals late tonight into Monday morning. Could see some IFR ceilings and some fog develop over the southern terminals for a few hours Monday morning but confidence remains too low at this time to go introduce IFR ceilings and lower visibilities at this time. Will re-evaluate this potential for the 06Z TAF cycle. Stratus will lift/scatter out to VFR after 18Z Monday. && .PREV DISCUSSION... /issued 227 PM CDT Sun Sep 9 2018/ SHORT TERM... (Tonight and tomorrow) Drier and cooler... Abundant cloud cover over the region has kept temperatures on the cool side. Some of the MOS guidance have overnight lows dropping into the upper 50s. Drier air from the north will filter into the area tonight, but with high soil moisture content and moist boundary layer, temperatures this evening will have a hard time cooling off after sunset. Look for overnight lows in the low to mid 60s. The RAP13 and HRRR Hi-Res models depict a few isolated pockets of fog across the Interstate 10 corridor occurring in the early morning hours. Fog development will depend on how much dissipation of the mid level clouds occur during the overnight hours. Commuters along Interstate 10 along the sheltered areas could see patchy fog. Across the rest of the region, morning low clouds will slowly lift and we will get some peaks of sunshine by the afternoon. Temperatures will be modified again by the moist boundary layer due to the days of heavy rainfall saturating the ground. Highs tomorrow will be in the mid 80s. 40 LONG TERM... (Monday Night through next Weekend) The forecast thinking for the long term has not changed much in the last 12 to 24 hours. Models in the long term are generally drier for western central Texas than the last week, with a warming trend. Temperatures by the middle of the week should be back up to near normal (high in the upper 80s). Lows will be a little warmer than normal with Gulf moisture remaining in the area, slowing overnight cooling. A shortwave is still expected to move through on Tuesday, keeping a chance for showers and thunderstorms in the forecast for areas mainly east of an Abilene to Sonora line that afternoon/evening. Following that, we will see generally drier weather for the area, aside from a slight chance for isolated/scattered afternoon showers and thunderstorms for areas south of a San Saba to Brady to Sonora line each afternoon through the end of the week. Models continue to show a broad easterly wave moving into the area at the end of the week, giving the area a better chance for better coverage of showers and thunderstorms Friday into the weekend. However, while this appears to be the next best chance for rain, we are not expecting a widespread heavy rain event like we had the last several days. 20 && .PRELIMINARY POINT TEMPS/POPS... Abilene 62 82 64 83 / 0 5 5 10 San Angelo 64 85 65 85 / 5 5 5 10 Junction 66 85 67 84 / 10 10 10 20 Brownwood 64 82 67 82 / 5 5 10 20 Sweetwater 62 82 64 83 / 0 5 0 5 Ozona 63 83 64 84 / 5 5 5 10 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ 99/99/24