Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/12/19

Area Forecast Discussion
National Weather Service Bismarck ND
859 PM CDT Sun Aug 11 2019 .UPDATE... Issued at 858 PM CDT Sun Aug 11 2019 Latest radar shows moderate rain over south central ND with isolated thunderstroms confined near/along the southern border. Additional isolated showers were developing in the southwest. Farther upstream, a line of thunderstorms stretching from just west of Glasgow to Billings have been near severe to severe at times. Large scale ascent will become maximized in far eastern Montana and western North Dakota around 06z/1AM CDT, then pivot through overnight into Monday morning. There will be heavy rain, perhaps more focused in the west and north central. The other concern will be the possibility for damaging winds west into central overnight as the aforementioned line arrives into western North Dakota around 06z. Gust front convergence may develop as strong low level easterly flow remain pointed into the mean deep layered winds which are west to southwest aloft. The HRRR and ESRL HRRR are beginning to show signs of a bowing segment developing towards Bismarck between 10z and 12z Monday. Will continue to monitor conditions from Montana into western ND over the next few hours. UPDATE Issued at 602 PM CDT Sun Aug 11 2019 Multiple rounds of showers and thunderstorms with heavy rainfall continues to be the main hazard this evening/tonight. Heaviest rainfall totals this evening occurred in Bowman and near New England with around 2 inches in one hour. Soil moisture has been able to handle this well, but will monitor for future rounds and location. Movement of these heavier showers and thunderstorms have been progressive, which is helping to inhibit flash flooding potential. Uncertainty on exactly where and how many more rounds will actually develop remain high, as the CAMS are all over the place in terms of possible scenarios. && .SHORT TERM...(This evening through Monday) Issued at 259 PM CDT Sun Aug 11 2019 A severe thunderstorm threat exists for far southwest North Dakota this afternoon and evening with large hail, damaging wind gusts, and a nonzero tornado chance possible. Additionally, heavy rainfall and several rounds of thunderstorms in the southwest to south- central may cause a flash flooding concern overnight. This afternoon, the synoptic pattern was characterized by a potent shortwave rounding the Great Basin region with a 500mb speed max pushing into the northern Rockies. Smaller impulses were detected on water vapor imagery pushing over central Montana and northern Wyoming. At the surface, pressure falls were noted in southern Montana and northern Wyoming where cyclogenesis and convergent upslope flow was ongoing. In north-central through southeast North Dakota a surface high axis was in place. Widespread stratus was detected on visible satellite imagery within the western and southern peripheries of the surface high, extending from western North Dakota through the James River Valley. In the southwest through south-central, skies have been clearing with the subsequent development of a cumulus field over the last several hours. A severe thunderstorm threat is expected to develop late this afternoon and evening in southeast North Dakota. Surface dew points in the low 60s beneath midlevel lapse rates of 7-7.5 C/km will develop MLCAPE values in the 1000-2000 J/kg range. Strong midlevel flow marked by 30-40 kts of effective bulk layer shear will combine with this instability to create a potential severe thunderstorm parameter space. With generally unidirectional hodographs depicted in southwest ND forecast soundings, splitting cells with eventual storm mergers will be likely. Thus the severe threat at the moment seems to be contained mostly to our southeast counties where initial cells may produce large hail and locally damaging wind gusts before becoming congealed. Additionally given strong deep layer shear, ML LCL`s around or below 1000m, and potential for discrete supercells...a tornado risk does exist. 0-1 km SRH is rather low, though the other ingredients is enough to make it a risk worth highlighting. This evening, thunderstorm coverage is expected to increase across our southwest as the midlevel speed max exits the Rockies. Thunderstorms are forecast to develop in central Montana and move into the northwest counties by late this evening as well. By the time of their arrival they will likely be clustered and elevated so the severe risk further north is low. Heavy rain will be a concern with thunderstorms tonight as PWAT values of 1.25" to over 1.5" will continue to advect northward this evening. Widespread rainfall totals of 1 to over 2 inches will be possible. In the southwest where several rounds of convection are likely this evening and tonight, the totals may be greater. HREF guidance indicates areas of 2 to 4 inches will be possible in the southeast to south-central counties given multiple thunderstorm passages. That said, the lack of a reinforcing mechanism to redevelop thunderstorms in one location does tone down the flash flood threat some. Though storm propagation should be fast enough to mitigate flash flooding concerns, this will still need to be closely monitored especially if a couple thunderstorms move over more populated areas. Scattered showers and isolated non-severe thunderstorms will continue through northern and eastern North Dakota early Monday morning before dissipating by mid-day. While the midlevel low is expected to briefly close off early Monday, guidance shows it becoming more progressive through the day and begin to move southeastward from northeast Montana through southeast North Dakota. A relatively thin instability corridor ahead of an advancing surface trough will pose a marginal severe threat Monday afternoon in the central and southeast. This will be highly conditional on daytime clearing and destabilization. Lingering precipitation and cloud cover Monday will also lead to cooler temperatures with highs in the 60s north and east to 70s south and west expected. .LONG TERM...(Monday night through Sunday) Issued at 259 PM CDT Sun Aug 11 2019 The long term forecast period is highlighted by almost daily chances for showers and thunderstorms with the active period continuing through the weekend. Monday evening the previously closed midlevel low rejoins the flow and dives southeastward through the Dakotas, dragging an attendant cold front through the area overnight. Pressure rises behind the front may bring breezy overnight winds however the magnitude is fairly uncertain given this occurring through the diurnal minimum and boundary layer decoupling. Some lingering showers will be possible Tuesday though the trend will be towards clearing with a surface high developing beneath midlevel height rises. NAM/GFS MOS guidance shows widespread high temperatures of mid 60s to around 70s likely Tuesday afternoon though the ECMWF has been a few degrees warmer. NBM blend of upper 60s to around 70 captured this well. Wednesday through Friday, the synoptic pattern is characterized by generally northwest flow aloft with daily chances for showers and thunderstorms. Midlevel flow stays fairly strong through the period so chances for severe weather in the region continue through the week (though uncertain in coverage and location at the moment). This weekend, ensemble and deterministic guidance has been consistent in developing a strong northwest trough and tracking it eastward through the weekend. While run to run details in wave timing, return flow, etc have been inconsistent...ensemble guidance in the CIPS analogs and GEFS plumes have shown some sort of signal for higher chances of thunderstorms and possibly severe weather. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 602 PM CDT Sun Aug 11 2019 Showers and thunderstorms highlight the taf period through 12z Monday, with possibly more precipitation across the northern terminals Monday afternoon. Heavy rainfall will result in MVFR to IFR cigs/vsbys at times. Expect the precipitation to wane from west to east 06z-12 Monday. Should see a break through 18z with MVFR cigs improving to low vfr. More showers/thunderstorms are forecast after 18z Monday, mainly over the northern and south central terminals of KISN/KMOT/KBIS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...AE LONG TERM...AE AVIATION...KS
Area Forecast Discussion
National Weather Service Cheyenne WY
954 PM MDT Sun Aug 11 2019 .UPDATE... Issued at 947 PM MDT Sun Aug 11 2019 All severe weather hazards have ended for the evening and updated zones and hazardous weather outlook have been posted. The convective cloud shield from earlier showers and storms and ongoing activity in central Nebraska to Colorado remain over the western Nebraska Panhandle this hour. Low cloud ceilings continue at KSNY due to all the rainfall an boundary layer moisture present underneath the convective cloud shield. With all the rain that did fall today in the Panhandle - expected areas of low clouds and fog overnight in the Panhandle and perhaps towards Niobrara County as well. Patchy IFR ceilings and visibilities will need to be monitored for and likely incorporated in the 06Z TAF cycle. Much drier conditions expected Monday and Tuesday where a Red Flag Warning and Fire Weather Watch highlights are in place in SE WY. Don;t have high enough confidence on issuing a Red Flag Warning at this time for the High Plains of WY given the marginality of the winds and humidity plus the rain that did occur today. Will let overnight shift assess latest trends. UPDATE Issued at 130 PM MDT Sun Aug 11 2019 Severe thunderstorm watch #570 in effect till 8 PM MDT for all Nebraska Panhandle Counties and the following counties in southeastern Wyoming, Converse, Niobrara, Platte, Goshen, and Laramie Counties. UPDATE Issued at 1219 PM MDT Sun Aug 11 2019 Storm Prediction Center with their 16z update have continued the trend for overall slight risk of severe weather this afternoon. Trended PoP and QPF values to reflect a blend of the HRRR, GFS, and NBM to cover the main spatial trends. Thinking the convective initiation of the HRRR is too far eastward considering the last couple hours of KCYS radar reflectivities and beginning of storms now along the Southern Laramie Range. Main threats remain strong thunderstorm winds, hail upwards of 2 inches possible along with an isolated tornado or two. Storms should begin as initial supercells on the WY high plains before consolidating into an eventual bowline structure. Dewpoints at the moment sitting in the 60s from the Laramie Range eastward into the NE Panhandle. Main timing of storms will be from about 1 PM through 8 PM. && .SHORT TERM...(Today through Monday Night) Issued at 200 AM MDT Sun Aug 11 2019 Severe thunderstorms today...followed by fire weather concerns Monday are the forecast challenges this morning. Currently...Complex situation across the area this morning. First off...a hug MCS has developed over northwestern Kansas and southwestern Nebraska this morning and shows no signs of weakening. Most of northern Kansas and southern Nebraska is under this MCS. Water vapor imagery showing a good plume of subtropical moisture in eastern Utah and western Colorado this morning...lifting north into south central Wyoming at this time. Latest GFS PWATS showing close to 1.0 inch in this plume as it moves into our area. Off to the northwest...a Pacific low pressure system is currently tracking across eastern Oregon...moving northeast into western Montana. Finally on surface analysis...we have a surface boundary that looks to be laying along the east slopes of the Laramie Range...northwest into southwestern Montana. East of this front...dewpoints in the 60s being observed in the Panhandle...with 40s in Albany County and northwestern Colorado. Models remain consistent on the solution for todays forecast. A disturbance in the monsoonal flow is forecast to tracks into northeastern Colorado and southern Nebraska Panhandle by this afternoon. This disturbance...along with the northwestern low are expected to begin lifting the stationary surface front to the northeast this afternoon as a warm front. Mesoscale guidance showing developing over the Laramie Range around 18Z...lifting northeast along the warm front as the afternoon progresses. Signatures on simulated radar from HRRR and Hires-NMM initially showing discrete supercells that form into bowing segments in the northern Panhandle as they move northeast. GFS surface based CAPE initially around 1500 J/KG at 18Z...increases to 2500-3000J/KG by 21Z across Niobrara County and northern Panhandle by 21Z. 0-6km shear increasing to 40-45kts should be sufficient for supporting these supercells. Do expect all modes of severe convective weather to develop with these storms today. Warm front looks to clear the northern Panhandle by mid evening...a little slower than what we were seeing 24 hours ago. Held onto high PoPs in the Panhandle through 03Z before decreasing at 06Z. Very dry air behind the front begins to shift into southwest Wyoming after 06Z and into Carbon County by 12Z Monday. GFS showing PWATS down to .2 to .3 inch across Carbon County by that time with 700mb winds increasing to 25-30kts. Still very confident in critical fire weather conditions developing over southwestern and western Carbon County Monday late morning that continues into the early evening. Decided to upgrade the Watch for southwest Carbon County (FWZ 304) to a Red Flag Warning for Monday. Confidence not so high for FWZ left as a watch for the time being. Am not getting the lower humidity at this time...only getting down to the upper teens over western Laramie and Platte Counties Monday afternoon. Will give the day shift another look to see what the 12Z guidance shows. .LONG TERM...(Tuesday through Saturday) Issued at 200 AM MDT Sun Aug 11 2019 Tuesday...Northwest flow aloft prevails. With a surface boundary across our eastern counties and adequate low and mid level moisture, we may see isolated afternoon and evening thunderstorms along and east of a Cheyenne to Chadron line. Wednesday...Although the flow aloft remains northwest, warmer temperatures aloft and a drier airmass will likely limit any shower or thunderstorm development. This will also aid in a decent warming trend. Thursday...The low amplitude ridge axis moves off to our east and temperatures will continue to warm with 700 mb temperatures near 16 Celsius. The cap may be just weak enough to allow for isolated thunderstorm development east of a Douglas to Cheyenne line in the evening. Friday...The flow aloft backs to southwest. As a low level boundary develops over our eastern counties, we may see isolated late day showers and thunderstorms east of a Douglas to Cheyenne line. Saturday...Mostly dry due to warm temperatures aloft limiting convective potential under southwest flow aloft. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 554 PM MDT Sun Aug 11 2019 Ongoing convection across the NE Panhandle expected to continue for the next few hours with brief periods of MVFR conditions in heavy thunderstorm rain bands. Some erratic winds may be possible as well. Clearing behind the storms will continue on the WY side and into NE later this evening with ceilings becoming FEW to SKC as drier air is advected in. && .FIRE WEATHER... Issued at 1220 PM MDT Sun Aug 11 2019 Widespread isolated to scattered showers and thunderstorms possible this afternoon ahead of shift in drier atmospheric conditions. Fairly dry conditions expected to persist through the week allowing for additional curing of fuels and increased risk for wildfire spread. Critical fire weather conditions still on track for FWZ 304 for Monday. RH levels and winds for FWZ 310 on Monday still seem borderline to hold the watch for another model cycle seeing as convection this afternoon may wet fuels enough to limit fire growth tomorrow. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Red Flag Warning from 11 AM to 7 PM MDT Monday for WYZ304. Fire Weather Watch from Monday morning through Monday evening for WYZ310. NE...None. && $$ UPDATE...JSA SHORT TERM...GCC LONG TERM...RUBIN AVIATION...WM FIRE WEATHER...WM
Area Forecast Discussion
National Weather Service Dodge City KS
1025 PM CDT Sun Aug 11 2019 ...UPDATE TO SYNOPSIS... .SYNOPSIS... Issued at 1023 PM CDT Sun Aug 11 2019 WV imagery indicates a southwest flow aloft prevailing across the Western High Plains. Meanwhile, an upper level shortwave trough is pushing eastward across the Pacific Northwest. Near the surface, an area of low pressure is anchored in southeast Colorado with an attendant frontal boundary extending eastward through western Kansas. && .SHORT TERM...(This afternoon through Monday) Issued at 1130 AM CDT Sun Aug 11 2019 Last night`s MCS was exiting eastward through Missouri at midday, with sunshine, an increasing south wind, and a few degrees of warming expected this afternoon. Most locations will warm well into the 90s this afternoon, with a few locales near the Oklahoma border reaching 100. Boundary layer moisture is still very high, with surface dewpoints within a few degrees of 70, all the way back to the far western zones. As such, instability will mount quickly again this afternoon, with CAPE increasing to near 3000 J/kg and lifted indices falling to -7C. Triggering mechanisms are again limited this afternoon, but a weak disturbance approaching from the south (producing thunderstorms near Amarillo at midday) may generate some isolated convection focused on the southern/SW zones through 7 pm as the latest HRRR iterations suggest. Around 7 pm this evening, all models are unanimous showing strong thunderstorm development/organization in NE Colorado, as stronger shortwave forcing arrives off the Rockies. 12z NAM and most of the CAMs/HRRR show a strong MCS rolling through WFO Goodland`s CWA this evening/tonight, into SW Nebraska. This MCS will probably have more severe wind associated with it tonight compared to last night`s previous MCS, but am confident the vast majority of thunderstorm activity will bypass SW KS to the north. Kept the scattered/chance category pops across the northern zones tonight as inherited, and as 12z NAM suggests, but these are likely overdone. Despite saturated soils across Trego county and vicinity after last night`s MCS, feel no need to issue another flash flood watch for tonight. A low level jet is expected this evening, with 12z NAM increasing SW 850 mb winds to near 50 kts, feeding the MCS to the north. This will keep south breezes elevated in SW KS this evening and slow the diurnal temperature drop. After midnight, a weak cold front/outflow boundary/wind shift will deliver a light NW wind shift through Monday morning, allowing areas west of US 283 to fall into the 60s. The light NW/N winds behind the boundary will offer several degrees of cooling on Monday, and with MOS guidance trending slightly cooler, trimmed Monday`s max temperatures some back to the lower 90s (very near normal for mid August). Shortwave over NE New Mexico sunrise Monday is expected to spread into SW KS during the peak heating afternoon hours, rotating around the subtropical anticyclone centered over the Arklatex. Scattered thunderstorm development will favor the SE zones Monday afternoon/evening. 12z NAM shows enhanced 0-3km EHI along the convergence axis across the SE counties late Monday, and SPC`s 5% wind/hail probability for the SE zones is reasonable. .LONG TERM...(Tuesday through Sunday) Issued at 200 PM CDT Sun Aug 11 2019 Summer upper anticyclone centered over central Texas late Monday will continue retrograding westward to near El Paso by late Tuesday. All zones are forecast to remain dry daylight Tuesday, given subsidence behind the departing shortwave. Light afternoon easterly/upslope wind components will keep the heat at bay Tuesday, with max temperatures only in the upper 80s and lower 90s. Northwest flow aloft, around the El Paso ridge, will direct any daily mountain convection southeastward into the western zones (primarily west of US 283) Tuesday night, and the NBM pops reflect this. Temperatures on Wednesday will remain relatively mild for mid August, as a central plains surface ridge will prevail, forcing surface winds with an easterly component and preventing downslope. Many locations should hold in the upper 80s Wednesday afternoon. Again, daylight Wednesday should be mostly dry. 12z ECMWF suggests another round of convection will impact the western zones late Wednesday, in response to continued NW flow aloft around the Desert SW ridge. NBM pops show this trend, but the slight rain chances currently in the forecast for late Wednesday will likely need to be raised with future forecasts. Appears to be a rather classic NW flow convective pattern. After Wednesday, the subtropical upper high weakens substantially, squashed and compressed into Mexico, in response to a strong upper trough in the Pacific NW Thursday, and passing through the northern Rockies Friday and Saturday. This synoptic evolution will force flow aloft to gradually become SWly, which is a warmer, drier and windier pattern for SW KS. Expect afternoon temperatures to gradually warm, south winds to increase, and rain chances to largely end, Thursday through next weekend. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 505 PM CDT Sun Aug 11 2019 Isolated convective development is possible around the GCK-DDC-LBL areas through this evening, but convective coverage will be limited. As such, confidence on direct impacts on the airports is low, and largely left out of the TAFs. Still expecting a large complex of thunderstorms to pass just north of a Scott City-HYS line during the 00-09z Mon time range. Some scattered convection will likely occur near HYS tonight, with enough confidence for a convective TEMPO group in the HYS TAF, but still feel strongest impacts to aviation will pass north of HYS. A low level jet is expected to increase to near 50 kts at 850 mb tonight, and included LLWS in all TAFs around 06-09z Mon. A light NW wind shift is expected behind a weak cold front through Monday morning. VFR and scattered to broken mid clouds are expected daylight Monday, with N/NE winds of 10-20 kts. Thunderstorm redevelopment is expected along and south of a LBL-DDC line after 21z Mon. && .PRELIMINARY POINT TEMPS/POPS... DDC 72 92 66 91 / 20 30 30 10 GCK 66 92 62 90 / 20 20 20 0 EHA 67 93 63 91 / 20 20 20 10 LBL 70 94 65 92 / 20 20 20 10 HYS 69 91 66 88 / 50 10 20 0 P28 76 99 69 91 / 10 30 30 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JJohnson SHORT TERM...Turner LONG TERM...Turner AVIATION...Turner
Area Forecast Discussion
National Weather Service Duluth MN
1054 PM CDT Sun Aug 11 2019 .SHORT TERM...(This evening through Monday night) Issued at 404 PM CDT Sun Aug 11 2019 A shallow cold front was located over our southern forecast area this afternoon. A region of 925 and 850 mb convergence and frontogenesis stretched from near Brainerd to just south of the Twin Ports and east-northeast over western Lake Superior. This region of forcing for ascent has supported isolated to scattered showers during the past few hours. The latest runs of the HRRR and HRRR Experimental seem to have a handle on the general flavor and location of the showers. Convergence and FGEN decreases this evening and think showers will diminish within an hour either side of 7 PM. Lingering clouds and moisture over the Northland should buoy temperatures with lows in the low 50s north to the upper 50s and low 60s south. A shortwave trough over Montana and Wyoming this afternoon will ride northeastward across the Northern Plains tonight and into western Minnesota by 12Z Monday morning. Light rain and possibly a few rumbles of thunder are expected ahead of the trough and should move into our western zones by late Monday morning. The initial surge of precipitation may dissipate over northern Minnesota by late afternoon while another surge of precipitation moves into northwest Wisconsin. Rain shower and thunderstorm chances increase overnight as a deeper trough moves into the eastern Dakotas and western Minnesota. Highs Monday will trend a little cooler with upper 60s and low 70s north and upper 70s south. Lows Monday night will be in the low 50s north to the upper 50s south. .LONG TERM...(Tuesday through Sunday) Issued at 404 PM CDT Sun Aug 11 2019 A potent upper level shortwave will move across the area on Tuesday and Tuesday evening, and have brought some likely pops to parts of the area Tuesday morning, when confidence in the precipitation is highest. With the surface low to our south, I have limited the thunder to no more than chance, as we may not be able to bring enough instability in for more widespread thunder. Temperatures will be on the cool side, with highs in the upper 60s to no more than mid 70s. Precipitation moves out by Tuesday evening. The retreating clouds and drier airmass moving into the area should allow temperatures to drop off to the mid 40s to low 50s, another cool night. Wednesday should be a quiet with a weak ridge axis sliding across the area. Some weak shortwaves may move across the area in the Thursday-Friday time range with northwest flow aloft and a weak baroclinic zone setting up over the area aloft. There is little model agreement in the timing of such shortwaves though, and have kept pops in the slight to low end chance pop range. Model agreement only gets worse by Saturday, as some models shove a fairly decent ridge axis and warm air into the area, but others have a potent upper level shortwave moving across the area. Have poor confidence in the forecast at this point, and have kept pops low still, but I did allow temperatures to get warmer with highs by Saturday back in the 70s and low 80s. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 704 PM CDT Sun Aug 11 2019 What minimal shower activity there is will decrease this evening affecting only KHYR for the first hour or so of the TAF period. A system approaches Monday evening and will bring widespread shower activity to the area. Fog shouldn`t be a problem tonight due to drier air that has moved into the area from the north. There may be a little patchy fog near KBRD and KHYR as the front stopped near there allowing the moisture content of the air to be relatively higher there. && .MARINE... Issued at 1028 PM CDT Sun Aug 11 2019 Not a whole lot happening on the marine side of the house, but there will be an increase in northeasterly winds as a system approaches which will increase winds near the head of the lakes and wave heights as well. && .PRELIMINARY POINT TEMPS/POPS... DLH 57 72 57 69 / 10 10 50 60 INL 51 71 53 74 / 0 50 50 30 BRD 59 74 57 70 / 20 30 50 40 HYR 57 77 57 72 / 30 20 50 50 ASX 55 71 57 72 / 0 10 40 50 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ SHORT TERM...Huyck LONG TERM...LE AVIATION...Wolfe MARINE...Wolfe
Area Forecast Discussion
National Weather Service Quad Cities IA IL
620 PM CDT Sun Aug 11 2019 ...AVIATION UPDATE... .SYNOPSIS... Issued at 308 PM CDT Sun Aug 11 2019 Afternoon surface analysis shows a surface low in northern Iowa in the vicinity of KMCW with a warm front stretching southeastward towards KSQI and then southward to KPIA. The remains of a morning MCS continued to dissipate as it moves eastward across southern Iowa this afternoon. A cold front trailed the surface low to the southeastward to KDSM to southeastern Nebraska. As of 3 PM temperatures ranged from 76 degrees at KFEP to 84 degrees at KBRL, KIIB, and KMPZ. Dewpoints were generally in the lower to mid 70s across the area. && .SHORT TERM...(This Evening through Tonight) ISSUED AT 308 PM CDT Sun Aug 11 2019 Short term period is this afternoon and tonight. The main model differences are between the Synoptic Models and CAMs. The main forecast concerns are chances of precipitation. The synoptic models are depicting the upper level support that brought todays showers and thunderstorms lingering across the area through 00 UTC Monday before shifting eastward along with the better moisture. This would give us a dry forecast through 12 UTC Monday. The Convective Allowing Models simulated radar reflectivity continue to keep convection festering across the area south of Interstate 80 into the evening hours. The current forecast is a compromise between these two ideas. The best chances for showers and storms will be south of a Fairfield to Galesburg line. A marginal risk of severe thunderstorms remains in place across the region. The main concern has been the risk of isolated damaging winds. Satellite is depicting decrease clouds to the west which could helps us to further destabilize late this afternoon and into this evening. Brief periods of heavy downpours are possible with any storms. .LONG TERM...(Monday through Sunday) ISSUED AT 308 PM CDT Sun Aug 11 2019 Monday Overview: A quick moving shortwave impulse and MCS will propagate from NE Colorado tonight to the Upper Mississippi Valley on Monday. Latest indications are for the storm complex to weaken as it heads into Iowa, outrunning the better LLJ convergence. With that said, the HRRR maintains a strong line into the southwest Monday morning before weakening it further. Leftover rain and embedded thunder can then be expected from the late morning into the afternoon especially across the northern two-thirds of the area. Severe Thunderstorm Potential: As surface-based instability rapidly increases through the mid to late afternoon south of I-80, and a surface low approaches, convective redevelopment is expected. The Storm Prediction Center has an Enhanced risk for severe storms over the south-central to southeast CWA, roughly southeast of a line from Aledo, IL to Kahoka, MO. A Slight risk extends further to the north and northwest. Best estimate on timing for severe storms is between 3 to 10 PM. The primary risks are damaging winds, isolated tornadoes, and localized flash flooding. Large hail is also possible with discrete cells. Moderate shear of 40-50 kts and high instability (2500-3500 J/kg of SBCAPE) are supportive of a supercellular storm mode with storms that redevelop during the afternoon/evening. Cold pool organization should lead to upscale growth into a linear structure with potential for enhanced wind damage in bowing segments later into the evening. Some uncertainty as to where the MCS matures. It could occur in our south and southeast, or focus more into central Illinois. The atmosphere will become anomalously moist with PWATs near 2 inches, setting the stage for a county or two wide corridor of 1-3" rainfall amounts. Models have been trending the heaviest rain axis southward. The HREF members are in decent agreement hitting counties south of I-80 and east of a Muscatine to Memphis, MO line with the highest rain totals. The ground is very dry, but for areas that receive hourly rain rates near 2", localized flash flooding is possible with urban locations of greatest concern. Held off on a Flash Flood Watch for now due to uncertainty on convective placement and potential for training storms. Uttech Tuesday...There may be morning fog in heavy rainfall areas if north sfc winds don`t increase in time. Will have to watch for northwest flow system in the wake of the passing Monday wave to possibly produce sctrd showers and storms in building afternoon instability especially north of I80. But for now will limit POPs until more confidence is attained. Wednesday through Saturday...After a below normal temp Wednesday, re- building thermal ridge upstream to the west will try to migrate eastward and make for re-bounding temps by late week and next weekend. In the process, still some chance for warm air advection fueled storm clusters in or near the CWA especially at night for portions of friday into Saturday. ..12.. && .AVIATION...(For the 00Z TAFS through 00Z Monday Evening) ISSUED AT 616 PM CDT Sun Aug 11 2019 A chaotic mix of VFR and MVFR cigs will continue to trend towards VFR this evening, with isolated storms possible, especially over central Illinois. A storm is possible at any time during the next 24 hours, but we will focus our attention towards the late afternoon hours Monday, as a wave of low pressure rides along a front over the region. This should drive a strong area of storms through the entire area, with some threat for damaging winds as they arrive, especially along and south of Interstate 80 in Iowa and Illinois during the afternoon and early evening Monday. Heavy rain, low visibility and hail are also possible, but with this in the extended period of the TAF, we have indicated an MVFR condition in cigs and visibility, with high confidence of that occurring, since we cannot yet identify the critical hours of VLIFR in strong storms yet. ERVIN && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Cousins SHORT TERM...Cousins LONG TERM...Uttech/12 AVIATION...Ervin
Area Forecast Discussion
National Weather Service Green Bay WI
954 PM CDT Sun Aug 11 2019 New Information added to update section .UPDATE... Issued at 949 PM CDT Sun Aug 11 2019 Clearing has been more progressive this evening than expected, so have made adjustments to sky cover for the rest of the night. Have also added more fog overnight into Monday morning, and suspect there will be areas of dense fog for the morning commute. Also lowered min temperatures a few degrees. && .SHORT TERM...Tonight and Monday Issued at 323 PM CDT Sun Aug 11 2019 Primary forecast challenge through Monday will basically revolve around cloud trends associated with weak and slow-moving weather systems. Low to mid-level clouds have been very stubborn today over most of the forecast area. This has resulted in cooler daytime maximum temperatures than forecast, except for the far north where more sunshine has allowed temperatures to climb into the upper 70s near the upper Michigan border. Clouds are the result of combination of weak upper-level impulse moving across the state and weak low- level thermal and moisture advection downstream of low-level trough axis over western Wisconsin late this afternoon. RAP soundings indicate that surface-based moist layer extends up to about 850 mb. Latest satellite trends indicate considerable cloud cover extending westward into southern Minnesota and all of Iowa, thus not especially optimistic to see much clearing over central and east central Wisconsin this evening and overnight. However some improvement has been seen last few hours north of Highway 8 where slightly drier air and a bit more mixing is occurring. HRRR and HREF also continue to suggest that perhaps a few showers could still pop-up over mainly the far northeast portion of the state ahead of aforementioned weak upper-level impulse and weak surface frontal boundary dropping southward from Upper Michigan. Kept low- end chance pops going mainly north and east of GRB into the early evening as per previous forecast. Overnight as surface trough slowly sags southeast of the forecast area, winds will begin to turn northeast with generally modest northeasterly flow setting up over east and eastcentral sections of the forecast area by Monday morning. Given residual boundary layer moisture will still be in place Monday morning, anticipate stubborn low clouds to persist well into the morning especially over the lakeshore and Fox Valley. Could also be some fog especially central and north with light winds and deep boundary layer moisture. HREF ensemble mean surface dewpoints and winds suggest a somewhat better push of drier air from the northeast, may commence sometime during the afternoon on Monday allowing for a bit more sunshine especially over the northeast third of the state. Expect more clouds to persist over southern and southwest portions of the forecast area closer to the next upstream shortwave impulse forecast to impact mainly northern Illinois into perhaps far southern Wisconsin Monday afternoon. Highs on Monday will generally be in the middle 70s most areas with cooler readings along the lakeshore with northeast boundary layer winds expected. .LONG TERM...Monday Night Through Sunday Issued at 323 PM CDT Sun Aug 11 2019 The medium range models have trended further south with the synoptic scale system Monday night and Tuesday. This track would result in a lower chance of showers and thunderstorms and less threat of northeast winds capable of producing shoreline flooding. Upper flow is forecast to become northwest Tuesday night through the end of the week. Slightly cooler than normal temperatures are expected Wednesday and Thursday as high pressure moves from the northern Plains to the Great Lakes. Heights rise later in the week, and low level winds turn to the south as the surface high moves off to the east. High temperatures could be 5 to 10 degrees above normal by Saturday with increased chances of thunderstorms as a slow moving cold front approaches from the west. && .AVIATION...for 00Z TAF Issuance Issued at 638 PM CDT Sun Aug 11 2019 There are several questions with the forecast this evening, including how far south the clearing associated with a weak cold frontal boundary will advance, how low ceilings will drop to overnight into early Monday, and where fog will develop. Clearing over northern WI has been slowly but steadily advancing south this afternoon. However, suspect that the clearing will stall after sunset, as the boundary layer starts to cool. With this in mind, will not forecast any clearing at the southern TAF sites, even though the back edge of the clouds has already progressed to a RRL-MNM line. Will be watching satellite trends closely during the early to mid evening. Assuming that clouds linger over all but the RHI TAF site, would expect that ceilings will steadily lower overnight, dropping to MVFR at most locations, and IFR locally. Some light fog may also occur. Farther north, where clearing has already occurred, the main concern will be fog development, as winds will remain light. Could see IFR/LIFR vsbys at RHI late tonight, as well as at several other airport sites in north central WI. Daytime heating on Monday should allow ceilings to gradually rise again during the day, with VFR conditions possible by mid to late afternoon at the southern TAF sites. A few showers could approach AUW/CWA late in the day. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........Kieckbusch SHORT TERM.....ESB LONG TERM......RDM AVIATION.......Kieckbusch
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1033 PM EDT Sun Aug 11 2019 .SYNOPSIS... Rainfall chances will slowly increase during the first half of the week, peaking on Wednesday with a weak cold front and remaining higher than normal into the weekend. Hot and humid conditions will persist through mid week, with a cooling trend toward the end of the week. && .NEAR TERM /THROUGH MONDAY/... As of 1030 PM EDT Sunday: All late evening PoPs have been pulled from the southern Appalachians as profiles have stabilized. Attention will now turn to a gradually improving easterly fetch of moisture in the 950 to 850 mb layer, and weak upglide developing overhead as mid-level vorticity lobes start arriving from the northwest through the early morning hours. Will thus bring back isolated shower chances along the eastern escarpment of the mountains through daybreak. Stratus should also fan out in areas away from the escarpment to provide developing cloud cover and keep mins mostly in the lower 70s east of the mountains. Another round of mountain river valley fog and low stratus is expected to form before the upglide induced clouds get started in earnest. On Monday, the low clouds in the morning may produce a late start on our warmup, which should keep the Heat Index from getting out of the 90s in all but a few parts of the Lakelands where the dewpoint will be highest. Think only the mtns will have a real chance of seeing any deep convection as a weak short wave moves in during the afternoon. East of the mtns, a lingering capping inversion should be enough of a limiting factor to keep the precip chances at bay. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... As of 230 PM Sunday: The longstanding upper ridge to our west will break down Monday night, and the pattern looks to remain quasi-zonal thru Tuesday. Nonetheless, 500mb heights will be similar if not slightly higher Tue compared to Mon, while 1000-850mb thickness peaks for the period. Dewpoints will remain elevated as low-level southerly flow regime continues. Combining temp and dewpoint guidance that has performed well recently, heat index is expected to rise above 100 throughout the Piedmont Tue aftn, with a smattering of locations pushing past 105 (generally due to local effects keeping dewpoints higher). We could make the argument that a Heat Advisory will be needed for Tuesday if guidance trends hold up. A cold front will extend from the Northeast to the Mid-South on Tuesday, in conjunction with a trough developing over the eastern CONUS and another deep ridge beginning to build over the Desert Southwest. Large instability is expected over the Ohio Valley ahead of the front, and some of the convection that develops there may propagate across the Appalachians into our area Tuesday night, along with the front. Confidence in the overnight PoPs is limited by differing model depictions of that activity and how much stabilization occurs in its wake. At any rate, the front is expected to remain in our vicinity through Wednesday, enhancing coverage of diurnal showers/storms across the Piedmont in conjunction with a weak shortwave embedded in the upper trough. The presence of these features implies storms may continue into Wed night. The height falls aloft along with additional cloud cover suggest max temps will trend downward slightly on Wed, though soupy dewpoints still are expected. Heat indices most likely will top out between 100 and 105. Regarding severe wx chances Tuesday, given the sweltering sfc conditions, we will have large sfc-midlevel theta-e lapses despite PWAT values near 2 inches. Shear will be on the gradual increase, so the earlier diurnal activity may be more of a pulsey nature, with multicells becoming increasingly likely as the day continues and also if activity propagates in from the west overnight. SPC has a portion of our area in the Day 3 marginal risk. The ingredients for severe weather on Wednesday are not all that different, but better shear will be available throughout the day, so clusters of storms near the frontal boundary may pose a wind and hail threat. && .LONG TERM /THURSDAY THROUGH SUNDAY/... As of 2 PM EDT Sunday: Starting Thursday morning with a dip in the jet stream as you may see an axis roughly from the Great Lakes to the Florida Panhandle. There will be a ridge over the SE States and from Bermuda eastward. The weak surface cold front will drift south of our area as waves of low pressure move along the front from the Gulf. The ECMWF is trending wetter toward the end of the week for the Deep South compared to yesterday. The EC has an apparent tropical low forming on Thursday and Friday then coming onshore near Pensacola to start the weekend. The EC has this feature over Tennessee Sunday night then turns it east toward the NC mountains. No need to get overly concerned since that is a week away and lots can change. The GFS on the other hand pushes the front down over Florida and brings somewhat drier air to our region. The models are in agreement that the SW ridge builds east at least briefly toward the end of the weekend. A strong northern shortwave approaches next week. Will have to wait to see how that pans out. Temperatures near normal for Mins and below by 3 to 5 degrees for Maxes Friday through the weekend. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... At KCLT and elsewhere: The early part of the overnight hours will see mainly FEW to SCT lingering stratocumulus with SCT to BKN cirrus. The main impact will be the potential for low clouds before daybreak, both from mountain valley fog and stratus and from Atlantic moisture advancing west into the terminal forecast area. The mountain valley fog/stratus seems a bit more certain, although even that could be affected by weak upglide producing higher stratus in the MVFR range. For the foothill and piedmont sites, the LAMP MOS has trended much more pessimistic, with solid IFR to LIFR cigs developing overnight and persisting into Monday morning. The RAP profiles have not had as much run-to-run consistency and advancing stratus could provide ceilings anywhere in the IFR to VFR range. The best compromise will be to feature mainly a daybreak window of low- end MVFR cigs at the foothill sites and KCLT, and keep the solid IFR to LIFR conditions confined to the mountain valleys and KAVL for now. Anticipate light ENE winds becoming a bit more SE then southerly with time. Conditions should scatter out to VFR at some point Monday afternoon throughout, with PROB for TSRA being reintroduced at KAVL only. Outlook: Coverage of showers and thunderstorms will increase Tuesday into Wednesday as a cold front and associated moisture/forcing arrive from the northwest. The boundary will stall southeast of the area mid to late week, with lower end convective chances persisting. Early fog/stratus will be possible each day across mountain valleys. Confidence Table... 02-08Z 08-14Z 14-20Z 20-00Z KCLT High 100% High 100% High 100% High 100% KGSP High 100% Med 78% High 90% High 100% KAVL High 100% Low 45% High 87% High 100% KHKY High 100% High 93% High 81% High 100% KGMU High 100% High 80% High 84% High 100% KAND High 100% Med 71% High 97% High 100% The percentage reflects the number of guidance members agreeing with the scheduled TAF issuance flight rule category. Complete hourly experimental aviation forecast consistency tables and ensemble forecasts are available at the following link: && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...HG/PM SHORT TERM...Wimberley LONG TERM...DEO AVIATION...HG
Area Forecast Discussion
National Weather Service Spokane WA
552 PM PDT Sun Aug 11 2019 .SYNOPSIS... Showers with embedded thunderstorms will cross Eastern Washington and the Idaho Panhandle into the evening. A few strong thunderstorms will be possible over the Northeast Mountains and in the Northern Panhandle with heavy rain being the primary concern. The shower threat retreats to mainly the mountains through the middle of the week, with another storm system expected around Thursday. Temperatures are expected to remain on the cool side of normal. && .DISCUSSION... Early evening update: Made some adjustments to the evening POP`s based on radar trends and latest HRRR model runs. A cluster of showers and thunderstorms between Wilbur and Hunters has produced an outflow boundary with showers and isolated thunderstorms on the increase in Lincoln county. HRRR shows this activity will continue to develop and move east into the Spokane and Coeur d`Alene areas early this evening. With the Spokane 00z sounding showing around 900 J/KG of CAPE this idea is accepted and thus have increased POP`s for this evening. Another area of showers between Republic and Northport will head east this evening as well towards Ione, Sandpoint, and Bonners Ferry. Meanwhile from Moses Lake to Pullman and points south there is very little activity on radar and thus have adjusted POP`s down in these areas, as well as along the East Slopes of the Cascades where downslope west winds will keep the remainder of the evening dry around places like Winthrop, Chelan, and Wenatchee. JW && .AVIATION... 00Z TAFS: Showers and thunderstorms around the Spokane and Coeur d`Alene area should be moving out around 02-04z as a low pressure system pulls away from the area. At this time storms are expected to be isolated so have not mentioned thunderstorms in the TAF`s but will be watching the radar closely for possible amendments. VFR conditions are expected this evening except under heavier showers and thunderstorms where conditions may briefly deteoriate to MVFR. Overnight models show the boundary layer saturating in the Idaho Panhandle with MVFR stratus expected to develop at KCOE by early morning. There is a small chance these CIGS could briefly develop at KGEG/KSFF as well. Otherwise drier weather is expected Monday with VFR conditions. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 51 76 51 82 55 82 / 70 0 0 0 0 0 Coeur d`Alene 52 75 49 80 53 81 / 90 0 0 0 0 0 Pullman 48 76 46 80 50 80 / 20 0 0 0 0 0 Lewiston 57 83 57 88 62 87 / 10 0 0 0 0 0 Colville 45 81 43 85 45 87 / 80 0 0 0 0 10 Sandpoint 50 73 47 79 49 79 / 60 10 10 0 0 10 Kellogg 53 72 53 79 56 79 / 60 0 0 0 0 0 Moses Lake 55 81 52 86 56 87 / 0 0 0 0 0 0 Wenatchee 60 81 61 84 63 84 / 0 0 0 0 0 0 Omak 58 82 57 85 59 86 / 10 0 0 0 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion
National Weather Service Riverton WY
200 PM MDT Sun Aug 11 2019 .SHORT TERM...(This evening through Monday) An early show of elevated convection has already taking place across the western half of the CWA in the form of innocuous shower activity. this loosely held band of showers is progressing east and at the time of this writing extends from Johnson County, down through Natrona County, Southeast Fremont County, and into Eastern Sweetwater County. Higher capes are beginning to pool across Johnson County. The HRRR is suggesting a fresh round of sfc based convection to get firing along and north of the Owl Creek Mtns and along and east of the Casper Arch (The Natrona/Fremont County line). Some other thunderstorms have formed over Eastern Sweetwater County. Weaker showers have formed over Western Sweetwater County which seems to mark the beginning of the cool front. The RH at RKS is currently 37 percent, KMM is 14 percent, and farther west, Evanston is down to 12 percent. KMM and Evanston are blowing out of the southwest at 29 and 28 knots respectively, so this is indeed the true dry punch. The other initial dry line sfc boundary will become established behind the anticipated potentially strong thunderstorms in Johnson County where a slight risk of svr is indicated, just behind the Gulf moisture feed. This dry feed moving in from the southwest will continue to nose in across the rest of the CWA with a resulting stabilizing of the environment and dropping RH values. Winds will calm down by 8 pm this evening. Sunday will feature slightly cooler temps and drier air along with breezy west winds behind the front/shortwave and under a westerly confluent steering flow. .LONG TERM...(Monday night through Sunday) Once today`s trough passes through the region, the flow will flatten out, with dry zonal flow continuing into the latter half of the week. Minimal to no rain chances expected through Wednesday, with temperatures gradually returning into the 80s and 90s. Next fluctuation starts to affecting the region Thursday as a trough dives into the Pacific northwest. While this added instability would mean a sharp increase in rain chances, the lower elevations will still be dry, so convection will be limited to to the higher elevations of north Wyoming, especially Thursday and Friday. The trough passes by to the north on Saturday, bringing an end to any further rain chances. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Area of showers and thunderstorms continues to move across the Wind River basin and south Wyoming, dropping a brief shower at KRIW and KRKS in the past hour. This area is moving to the northeast, and should move across the KCPR area later this afternoon. Most areas west of the divide and in the Big Horn basin are already clearing out, and likely won`t see any more shower activity today. Remaining showers are expected to move quickly northeast this afternoon, with quickly clearing skies. All areas will see light and variable winds tonight under mostly clear skies. && .FIRE WEATHER... |...Red Flag Warnings in effect this afternoon and evening for zones 283 and 288... ...Red Flag Warning in effect this afternoon and evening and Monday afternoon and evening for zone 280... ...Rangeland Fire Danger Statement this afternoon and evening for zones 277, 278 and 279... A "dry line" is expected to become established across our northern and northeast zones. Ahead of this line, strong, to possibly severe thunderstorms will occur this afternoon. A cold front is also currently moving across far Western Wyoming where the RH is already down in the low teens behind the front across Southwest Wyoming. other scattered thunderstorms will occur this afternoon, mainly from zone 281 to the far eastern portions of 279. Storms will mainly end across the area from southwest to northeast early this evening. Relative humidity values will quickly drop behind the front from west to east, becoming critical in the Wind River Basin and the southern zones. Gusty winds up to 35 mph will occur over the southern zones behind the front. && .RIW WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 4 PM this afternoon to 7 PM MDT Monday for WYZ280. Red Flag Warning until 8 PM MDT this evening for WYZ283-288. && $$ SHORT TERM...Lipson LONG TERM...Straub AVIATION...Straub FIRE WEATHER...Lipson
...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Monday) Issued at 324 PM CDT Sun Aug 11 2019 Another round of thunderstorms is looking likely tonight, mainly near the KS/NE state border, as a robust midlevel shortwave develops over the Colorado Rockies and lifts northeast into Nebraska. Storms have developed in eastern CO and will track east/northeast tonight. The ascent associated with the shortwave, enhanced by a LLJ late tonight will interact with a moist and buoyant airmass. The RAP and HRRR models have around 3000 J/Kg of MLCAPE in northeast KS tonight, and bulk shear values could be 35 to 40 kts as storms approach. Given those parameters, storms are more likely to stay organized and maintain strength. Severe thunderstorms will be possible, with 60 to 70 mph wind gusts being the most likely hazard. Additionally, Pwats are expected to remain around 2.0 inches, so heavy rainfall is likely with thunderstorms tonight. Flash flood guidance is lower following rainfall from last night. Thus, have decided to include Cloud, Republic and Washington Counties is a Flash Flood Watch during the overnight hours. Current QPF is for a general one to two inches of rain, but locally higher amounts will be possible, and rainfall is expected to accumulate quickly given the moisture content of the airmass and the expected strength of storms. Storms should quickly exit the area early tomorrow morning. The daytime hours of tomorrow are expected to be dry. The front in southerly Nebraska will sag southward into, and eventually move through, the CWA as the surface low works into northern MO/southern IA. Prefrontal compression, along with reduced mixing and higher dew points ahead of the front will make for a hot and humid day, especially along and south of Interstate 70. As such, a Heat Advisory will be in effect across east-central KS during the afternoon and evening hours with heat index values forecast to be between 105 and 110 degrees. .LONG TERM...(Monday night through Sunday) Issued at 324 PM CDT Sun Aug 11 2019 Transitioning into the extended period, the key points are: a brief cool down followed by a gradual warmup with intermittent rain chances through the period. By Tuesday evening the surface cold front responsible for tonight`s and tomorrow`s thunderstorm activity will progress southeast of the forecast area, ushering slightly cooler and drier air Tuesday into Wednesday. A few showers/storms are possible as it departs late tomorrow night into early Tuesday, although this potential is small. Weak surface ridging behind the aforementioned front combined with wet soil conditions could poise a fog potential Wednesday morning. Temperatures look to remain quite seasonable for mid-August as the midlevel ridge axis amplifies across the Southwestern US. Afternoon highs look to remain in the 80s Tuesday through Thursday. The aforementioned midlevel ridge will overspread the High Plains late Thursday into Friday. As a result, the surface ridge axis will progress eastward allowing WAA to overspread the CWA on it`s western periphery. Showers and thunderstorms are possible late Thursday into Friday on the nose of a strong LLJ. Precipitation coverage could be enhanced by a shortwave trough translating through the midlevel flow. Temperatures will continue to warm through the weekend as the midlevel ridge axis overspreads the area, surging temperatures into the 90s Friday-Sunday. A deep midlevel trough is progged to come ashore in the Pacific Northwest, transitioning the Central US to southwesterly midlevel flow. Showers and storms are possible late next weekend as the aforementioned midlevel trough ejects across the Northern Plains, shunting a surface front through the area. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 634 PM CDT Sun Aug 11 2019 For the 00z TAFs, main focus is on the potential for a line of thunderstorms to track over the TAF sites overnight into Monday morning. The best chances for storms will be along the KS/NE border with some model uncertainty in just how far south these storms may extend. As a result, only have VCTS mentioned at this time. If storms track over the TAF sites, gusty winds will be possible at upwards of 25-35kts. VFR conditions are likely for the remainder of the TAF period. There is a chance for some scattered storms to develop late Monday afternoon/evening with a frontal passage, but confidence is too low in the timing/tracking of these potential storms to warrant a mention in the TAFs at this time. && .TOP WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM CDT this evening for KSZ054-058-059. Heat Advisory from 1 PM to 8 PM CDT Monday for KSZ026-039-040- 054>056-058-059. Flash Flood Watch from 11 PM CDT this evening through Monday morning for KSZ008-009-020. && $$ SYNOPSIS...Teefey SHORT TERM...Teefey LONG TERM...Baerg AVIATION...Hennecke