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

Area Forecast Discussion
National Weather Service Amarillo TX
633 PM CDT Mon Oct 8 2018 .AVIATION... 00Z TAF Cycle VFR conditions at all three TAF sites will become MVFR and even IFR to LIFR after 02Z to 04Z Tuesday through 00Z Wednesday as showers and thunderstorms track across the the Dalhart, Guymon and Amarillo TAF sites. East and southeast winds 5 to 15 knots will become north 10 to 20 knots with gusts near 25 to 30 knots after 02Z to 07Z Tuesday. Schneider && .PREV DISCUSSION... /Issued 402 PM CDT Mon Oct 8 2018/ SHORT TERM...Through tonight PREV DISCUSSION... /Issued 137 PM CDT Mon Oct 8 2018/ Storms have shifted focus to the east as expected. There is some clearing east of a trough that could allow a few discrete cells to form out that direction and the HRRR shows a few popping late this afternoon. This will have to be watched given continued high bulk shear and low LCLs that could lead to some quick spin- ups. Forecast sounding do show some veer/back/veer to the profiles, so it isn`t a textbook profile. As has been the case the last two days, the marginal instability should be the key that helps save us from a more significant/widespread severe event. Otherwise we may head into a slight lull, but arguably the strongest upper dynamics of the event will swing across the area overnight leading to another complex or storms that sweeps across the area from SW to NE between midnight and sunrise for most. Minimal instability may have limit the svr potential (per the marginal to slight risk favoring the SE), but hi-res model agreement on on more significant complex of rain and storms moving across the area as the front approaches and moves through makes sense. Updated grids a bit earlier to account for the timing and trends above and also raise POPs in the east/NE. 88 LONG TERM...Tuesday through Monday Cold front will clear all of forecast area by Tuesday morning, with clouds and cooler conditions expected. Additional strong dynamics with incoming shortwave trof will assist in precipitation production in regime of isentropic lift. Highest pops will be in northeast where richer moisture will linger near mid-level circulation. Lowest pops in southwest where drier air expected to create semblance of an intruding dry slot. Precipitation expected to end by Tuesday evening. Tuesday night will be cold as surface high pressure ridge settles into area. Lows Wednesday morning in the lower- to mid-30s expected for the northwest 1/3 of the forecast area. Next mid-level trof takes shape Wednesday and Wednesday night across the Great Basin, with southwest flow aloft resuming over Panhandles. Remnants of Hurricane Sergio in eastern Pacific get ingested into this southwest flow, with moisture and circulation expected to impact West Texas mainly Friday night and Saturday. Cockrell && .AMA Watches/Warnings/Advisories... TX...Flood Watch through Tuesday morning for the following zones: Armstrong...Carson...Collingsworth...Donley...Gray... Hemphill...Hutchinson...Lipscomb...Ochiltree...Palo Duro Canyon...Potter...Randall...Roberts...Wheeler. OK...Flood Watch through Tuesday morning for the following zones: Beaver. && $$ 11
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
927 PM CDT Mon Oct 8 2018 .UPDATE... New showers and thunderstorms have developed south of Bexar County the last hour and now affecting parts of Bexar County and areas along the I-35 corridor. Looking at the latest water vapor images, there is an upper level short-wave moving across the southern part of south central Texas where the activity is taking place. Also, the SPC Mesoscale Analysis website points out to an area of upper-level divergence right over the area where the upper level wave is moving across and lineup well with the I-35 corridor. Latest HRRR model guidance suggest for this activity to continue through late tonight with another pulse of energy coming across over same areas overnight. There could be pockets of 1 to 2 inches of rainfall with stronger storms as pwats remains between 1.8 to 2.0 inches over those areas. Things out west are not bad at this present time with only one cluster of strong storms barely touching the northwest part of Val Verde County. This situation may not last long as things get interesting close and after midnight tonight as the main upper level disturbance over the four corners region moves to the northeast. Expect the threat for heavy rain and flash flooding to continue overnight as the severe threat diminishes. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 72 83 66 83 60 / 40 70 50 10 - Austin Bergstrom Intl Airport 72 84 66 83 59 / 40 70 50 10 - New Braunfels Muni Airport 73 83 66 84 60 / 40 70 50 10 - Burnet Muni Airport 71 80 61 81 56 / 50 80 40 - - Del Rio Intl Airport 71 84 63 86 66 / 80 60 10 - 10 Georgetown Muni Airport 72 82 63 81 57 / 40 70 50 - - Hondo Muni Airport 73 84 65 86 61 / 50 70 40 10 - San Marcos Muni Airport 73 83 67 84 60 / 40 70 50 10 - La Grange - Fayette Regional 74 86 69 85 61 / 40 60 50 10 - San Antonio Intl Airport 73 84 67 85 61 / 40 70 50 10 - Stinson Muni Airport 74 84 68 86 63 / 40 70 50 10 - && .EWX WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch until 7 AM CDT Tuesday for Bandera-Edwards-Kerr- Kinney-Maverick-Real-Uvalde-Val Verde-Zavala. Flash Flood Watch through Tuesday afternoon for Gillespie-Llano. && $$ Mesoscale/Aviation...Platt Synoptic/Grids...17
Area Forecast Discussion
National Weather Service Fort Worth TX
1041 PM CDT Mon Oct 8 2018 .UPDATE... A strong warm and moist air advection regime continues to supply North and Central Texas with sufficient moisture and lift to allow showers to continue well into the evening hours. An overall weakening trend is expected for the activity lifting north along I-35, but the high coverage of light precipitation warranted a grid update to increase POPs for tonight. Meanwhile, a line of thunderstorms just west of the forecast area is showing signs of weakening as it approaches our western counties. However, its outflow boundary is about to collide with the northwestward-moving outflow which pushed through the Metroplex earlier this evening, which may cause an increase in convection for an hour or so across the western row of counties. Likely POPs have been moved up in time for this reason for the west and northwest. Brief heavy rain and localized flooding will be the primary concern with this activity. Additional thunderstorms will organize out west and approach the area Tuesday morning ahead of the strong upper trough over the Four-Corners region. Likely POPs will remain in place for areas along and west of I-35 Tuesday morning, with a few strong to severe storms possible. At this time it still appears that the better severe threat will occur Tuesday afternoon and evening when the best instability will be in place. 30 && .AVIATION... /Issued 742 PM CDT Mon Oct 8 2018/ 00 UTC TAFs Concerns---Short term rain/thunder potential at all TAF sites. Return of MVFR stratus overnight into Tuesday morning along with rain/storm potential through the day. Showers and a few storms continue to lift northward this evening between ACT and the Metroplex TAFs. Total lighting information indicates that much of this activity is losing some of its vigor and given the loss of daytime heating plus earlier storms across the Metroplex, I`ll abstain from a VCTS mention at this time and advertise SHRA. If activity persists a little longer, I`ll include a brief 2-3 hour period of VCTS at Metroplex TAFs. Regardless, impacts to southbound traffic and the Glen Rose/Cedar Creek cornerposts do appear probable. Storms have cleared Waco, but a few showers will remain possible through the overnight hours. MVFR stratus is expected to blanket the area during the overnight hours with cigs falling to near FL012. Given the moist airmass, I wouldn`t completely rule out a few brief periods of IFR, especially at Waco. At this time, however, the potential is too low to include. Storms appear like a good bet at Metroplex TAFs between 1500 and 1900 UTC and will likely have some impacts on the Tuesday morning to early Tuesday afternoon push. There should be a brief reprieve from the potential for TS in the afternoon before another round of TS develops to the west during the evening at the Metroplex. At this time, it appears that the most likely window for this second round of convection will be between 0200 and 0400 UTC Wednesday. At Waco, storms will likely re-fire in the afternoon, closer to 2000 UTC Wednesday. Surface winds will become westerly Tuesday evening before becoming northwesterly around midnight with a potential for post-frontal MVFR stratus. Bain && .SHORT TERM... /Issued 355 PM CDT Mon Oct 8 2018/ /Through Tonight/ Another afternoon of showers and thunderstorms is underway as we remain positioned downstream from a deep upper trough. Lift from this system has contributed to a broad area of convection across the western portion of the forecast area, as well as isolated convection farther to the east. This trend should continue for the next few hours before activity wanes later this evening. Through the peak heating hours, a couple strong storms will be possible, mainly due to the presence of strong surface based instability. SBCAPE values are 1500-2000 J/kg across much of the forecast area, where some breaks in the clouds have contributed to surface heating. Moderate shear values and unidirectional profiles should continue to limit the organization of strong or severe storms. However, strong winds would be the main hazard with more robust convection, along with brief heavy rain and lightning. Otherwise, the broad area of showers and isolated storms ongoing from Killeen to Gatesville should make northeastward progress towards the I-35 corridor later this evening, while also weakening. Overnight, a potent shortwave digging through the upper trough will generate a large complex of thunderstorms across West Texas which will move towards our western counties prior to daybreak. Some of this convection may reach strong/severe limits at times with predominantly a wind threat. However, its intensity may be declining after it enters our forecast area as it outruns upper support to the west. Heavy rain and flooding will also be a concern early Tuesday morning, especially if this line was to slow down or stall, causing cell training to occur. The evolution of this line and subsequent weather threats on Tuesday are discussed below. -Stalley && .LONG TERM... /Issued 355 PM CDT Mon Oct 8 2018/ /Tuesday through Monday/ Our slow moving upper trough to the west will finally be on the move Tuesday spreading rain and thunderstorms across the region. A fairly well organized line of thunderstorms should be ongoing early Tuesday morning across west Texas as strong forcing for ascent spreads across the Panhandle and into the Southern Plains. This line of storms will likely be approaching our western counties prior to sunrise. Latest runs of the high resolution guidance continue to show a weakening trend through the early morning as the line approaches the I-35 corridor. This makes sense given that the upper trough will likely eject north-northeast, taking the best upper jet dynamics and forcing for ascent with it. In addition, the strongest portion of the low level jet will also transition northward. As we get into midday and the early afternoon, the upper trough axis will spread into west Texas. Despite our being removed from the best upper forcing, the system will remain quite dynamic across our region and we should see a reinvigoration of convection near the I-35 corridor as the atmosphere destabilizes. With deep moisture (PWs of 1.8 to 2") remaining in place and an increase in low level convergence expected in the uncapped environment, we should see rapid development of new convection into the afternoon and evening hours. The latest 3km NAM and HRRR are most aggressive with this scenario and are also the slowest of the guidance. With the upper trough moving almost due north initially, this would keep deep meridional flow in place across North Texas, and would suggest a slow eastward movement initially with any new convection. This would also allow several hours of afternoon destabilization to occur along and east of I-35. The upper trough will eventually swing through late tomorrow evening allowing any additional convection to spread eastward. The severe threat will be dependent upon how much morning activity occurs and how late the afternoon convection develops. If the latest trends in the high res guidance continue then it appears we will become quite unstable by tomorrow afternoon, especially across our eastern counties. While lapse rates are marginal, the hail threat appears pretty low, but damaging winds would certainly be possible with the strongest storms. There will continue to be a conditional tornado threat given the low LCL`s and instability, and would certainly have to be monitored in areas where surface winds are backed in the vicinity of any mesoscale boundaries. We`ll have high PoPs across the entire area for tomorrow and will hang on to them a little longer into the evening hours given the likelihood that the entire system is a little slower to depart the area. Concerning the flash flood potential...there will be a threat for heavy rainfall with any of the storms from this evening through Tuesday evening since we keep the near 2" PWs in place. Storm motions will be fast given the strong deep layer southerly flow, so despite rainfall rates of 1.5-2"/hr, they should not persist in any one area for very long. The only exception may be with the line of showers/storms during the early morning hours. We`ll have to watch the organization of this overnight. If it appears that it will make farther eastward progress than currently anticipated, then we could have some issues over our western counties. We`ll hold off on issuing any flash flood watches at this time. Rainfall should end from west to east quickly Tuesday night with Wednesday and Thursday being rather nice days. We`re still monitoring the potential for the remnants of Sergio to interact with a southward moving cold front later this week across the Southern Plains. We`ll keep 20-40% PoPs in for the Saturday-Sunday timeframe at this time with the best chances on Sunday. There may be some potential for heavy rainfall with this system. Temperatures behind this cold front will be much more fall like with highs in the 60s on Sunday into early next week. Dunn && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 72 80 62 77 56 / 50 90 70 0 0 Waco 72 83 64 82 58 / 50 80 70 0 0 Paris 70 80 64 77 54 / 50 70 90 0 0 Denton 70 79 60 76 55 / 50 90 70 0 0 McKinney 70 79 61 76 54 / 50 90 80 0 0 Dallas 73 81 64 78 57 / 50 90 80 0 0 Terrell 72 85 65 81 57 / 50 80 90 0 0 Corsicana 72 82 64 79 57 / 40 80 80 0 0 Temple 72 83 64 82 59 / 60 80 70 0 0 Mineral Wells 69 79 56 76 53 / 60 90 30 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 30/24
Area Forecast Discussion
National Weather Service North Platte NE
632 PM CDT Mon Oct 8 2018 .SHORT TERM...(This evening through Tuesday) Issued at 326 PM CDT Mon Oct 8 2018 Main forecast concern this period is precipitation for the rest of today and overnight and precipitation chances on Tuesday along with where the rain/snow line will set up. Drier air has moved in across southwest Nebraska and the HRRR seems to be the best model to have a handle on this so have trended towards the HRRR for precipitation chances tonight. Decided to get rid of the likely rain chances across southwest Nebraska keeping only chances in overnight as rainfall across this area should take a break for the next 6 to 12 hours. That being said have also reduced rainfall amounts overnight. Precipitation will stick around a little longer across north central Nebraska. Areas of patchy fog will mostly likely develop overnight towards morning, keeping visibilities low at times. For Tuesday, the upper level low, currently situated over southwest CONUS will continue to move northeastward across the High Plains region. High temperatures will remain cold with highs hovering above freezing across the northwest Sandhills. Bufkit soundings show cold air both at the surface, through the mid layer into the dendritic layer giving confidence that areas across the northwest Sandhills will see wet snow. The forecast becomes trickier the farther east and south just where the rain/snow line will set up. Current thinking is the rain/snow line will slowly progress eastward during the day but temperatures should remain just warm enough to keep most areas across southwest and north central Nebraska all rain through the day before changing over to a rain/snow mix in the evening. The best area for snowfall on Tuesday will be across the Sandhills, snowfall amounts will be light through the day. .LONG TERM...(Tuesday night through Monday) Issued at 326 PM CDT Mon Oct 8 2018 All of the 12z models, SREF and 18z NAM models have tightened up and track a closed h700mb low through ncntl Nebraska Tuesday and Tuesday night. This should position a rain snow line across wrn Nebraska Tuesday afternoon which will move east Tuesday night. The frontogenesis is fairly strong and about 0.33 to 0.75 inches of liquid rain/snow is predicted by the models as this low lifts through. Rain changing to snow should end by 12z Wednesday morning with temperatures below freezing. The best guess on snowfall is 1 to 3 inches using snow ratios between 5 and 10 to 1. Road temperatures are still in the upper 30s to lower 40s across northwest Nebraska but another night of cooling could lower them into the 30s and then below freezing Tuesday night. The potential for icy roads Tuesday night appears high and a winter weather advisory is in place for parts of wrn and ncntl Nebraska beginning late Tuesday afternoon and ending Wednesday morning. A second storm system will follow on the heals of the system Tuesday affects wrn and ncntl Nebraska Thursday night. Todays model runs split a large portion of this storm through the Rockies and as a result, rain/snow chances across wrn and ncntl Nebraska are much lower. Lastly, the remnants of "Sergio" could produce a mix of rain and snow across srn Nebraska Saturday. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 632 PM CDT Mon Oct 8 2018 Periods of rain and possibly snow will continue through the forecast period, though the heaviest precipitation and greatest chances for snow come after 15z Tuesday. Expect IFR or lower through much of the period, with the potential of reduced visibility when the precipitation occurs, especially true at the KVTN terminal late Tuesday when a changeover to snow is expected. Overall confidence is high do to strong model agreement, but timing on the categorical changes is low, expect updates to the forecast as we follow the trends. && .LBF WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 4 PM CDT /3 PM MDT/ Tuesday to 9 AM CDT /8 AM MDT/ Wednesday for NEZ004>006-008-022>025-035-036-094. && $$ SHORT TERM...Gomez LONG TERM...CDC AVIATION...Jacobs
Area Forecast Discussion...UPDATE
National Weather Service Portland OR
851 PM PDT Mon Oct 8 2018 Updated Aviation section. .SYNOPSIS...Cloudy skies and period of rain and drizzle will continue across the region through Tuesday as a weak disturbance moves across the forecast area. Some showers continue late Tuesday, but begin to decrease after a cold front pushes south through the forecast area. Drier and milder weather will come later in the week as an upper level ridge of high pressure builds across the Pacific Northwest. && .SHORT TERM...Tonight through Thursday...Another impulse crossing the region today is maintaining abundant low clouds and light rain or drizzle across much of the forecast area. While any particular hourly total has been rather light, the persistent nature of this rain is adding up with anywhere from one to three tenths of an inch across many locations in the Willamette Valley, and locally higher totals along the coast and in the terrain of the Coast Range and Cascades where up to three-quarters of an inch have been measured in the last 24 hours. Not much change in the pattern of rain and clouds is expected for the next day or so. The strong shortwave moving through the Gulf of Alaska as it rounds the strong upper level ridge over the eastern Pacific will drop southeast across Washington and Oregon on Tuesday. Forecast models remain rather consistent with this feature, so have maintained the relatively high PoPs as this impulse moves through the region for one last organized round of rain this week. Behind this disturbance, some showers will linger but these showers will then becoming confined to the higher terrain of the Cascades by Tuesday night. Dewpoints will remain rather high and the rather moist lower levels of the atmosphere will keep low clouds and areas in fog in place both tonight and tomorrow night. This widespread cloud cover will also serve to keep temperatures a few degrees or more below seasonal normals for the next couple of days. Lingering low-level moisture into Wednesday should maintain some morning clouds, but a drying north to northeast flow should develop to begin to bring a return of clearing skies by Wednesday afternoon. This will likely result in a chilly and clear Wednesday night into Thursday morning, outside of patchy fog developing in portions of the valley. Thursday`s temperatures will trend to near seasonal normals with afternoon sun after the morning fog as high pressure strengthens over the region.Cullen .LONG TERM...Thursday night through Monday...The 12z GFS and 12z ECWMF are still in good agreement through the extended forecast period. A massive upper level ridge will be the dominating feature, as the weekend approaches the ridge axis looks to tilt slightly positive. As a result the surface high over the Columbia River basin, which in turn will cause a tightening of the surface pressure gradient leading towards an offshore flow pattern. This could lead to the most significant east winds so far this season, with gusts up to 35 to 45 mph near and in the western Gorge. Look for these gusts from late this week into the weekend. Overall during this time period the area will stay dry, along with temperatures around seasonal to slightly warmer than seasonal. Highs in the upper 60s to lower 70s, and lows in the mid to upper 40s. /42 && .AVIATION...Overall inland areas have seen the most improvement this evening with mainly VFR conditions south of KPDX. KPDX northward continues with MVFR to IFR cigs, and LIFR at the coast. Latest HRRR model show another impulse moving in from the northwest that may clip areas north of KSLE with lowering conditions overnight so could see low MVFR or IFR cigs return for a few hours. But after 12Z or so cooler air aloft should help mix the lower layers to improve to high end MVFR or VFR during the day Tuesday. Coastal areas likely to remain IFR or worse through midday Tuesday, perhaps longer. But forecast sounding do show a improving trend with cigs slowly lifting in the afternoon. Light offshore flow develops Tuesday night into Wednesday so expect a mix of IFR fog and stratus late Tuesday night. KPDX AND APPROACHES...Low end VFR to MVFR cigs in the immediate area of KPDX but IFR cigs not far away. HRRR model shows increasing chance of rain after 09Z Tues and satellite & radar show this feature. Based on that do think lower conditions are possible for several hours, the gradually improving as cooler air aloft arrives. /mh && .MARINE...Weak fronts will move across the waters through the first half of the week. The next one will bring advisory winds as well as increasing NW swell, enough that we`ve issued a Small Craft Advisory for Hazardous Seas in addition to the Small Craft Advisory for Winds which was issues this morning. Wind gust strength will be marginal south of Cascade Head, so haven`t issued anything for winds there. Models have been steadily increasing the seas forecast with the incoming swell, so while the current forecast is for a peak of 11-12 ft for the waters within 10 nm of the coast, they could end up even a foot or two higher than that. High pressure will build over the waters starting Wednesday afternoon, bringing the return of a summer-like northerly wind pattern for a few days. Seas will decrease during this period, staying around 5 to 6 ft Wednesday night through at least Saturday. Bowen && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory for winds until 7 PM PDT Tuesday for Waters from Cape Shoalwater WA to Cascade Head OR from 10 to 60 NM. Small Craft Advisory for hazardous seas from 5 AM Tuesday to 5 AM PDT Wednesday for Coastal Waters from Cape Shoalwater WA to Cascade Head OR out 60 NM.Waters from Cascade Head to Florence OR from 10 to 60 NM. Small Craft Advisory for winds from 5 AM to 2 PM PDT Tuesday for Coastal waters from Cape Shoalwater WA to Cascade Head OR out 10 NM. Small Craft Advisory for hazardous seas from 2 PM Tuesday to 5 AM PDT Wednesday for Coastal waters from Cascade Head to Florence OR out 10 NM. Small Craft Advisory for Rough Columbia River Bar from 2 AM to 7 AM PDT Tuesday. && $$ Interact with us via social media: This discussion is for Northwest Oregon and Southwest Washington from the Cascade crest to 60 nautical miles offshore. This area is commonly referred to as the CWA or forecast area.
Area Forecast Discussion
National Weather Service Blacksburg VA
1033 PM EDT Mon Oct 8 2018 .SYNOPSIS... A warm and moist southeast flow will continue over the region through midweek as high pressure begins to shift off the coast. This will lead to more clouds than sun with overnight areas of fog, with temperatures remaining above-normal for early October. Hurricane Michael is expected to move out of the Gulf of Mexico through the southeastern US by mid to late in the week. Impacts, if any, from Michael remain uncertain. && .NEAR TERM /THROUGH TUESDAY/... As of 1030 PM EDT Monday... Radar showed squattered showers from Grayson County Virginia into the northwest North Carolina mountains. HRRR and Hi-Resarw maintained at least isolated showers in that area through midnight. 00Z RNK sounding showed moisture through the lowest 3000 feet of the atmosphere with southeast winds extending up to about 10,000ft. With that upslope expect clouds to continue to develop. Models showed widespread cloud cover by 06Z/2AM across much of the Blue Ridge and foothills. Similar to past few nights, fog will fill in the valleys, especially where it takes longer for clouds to form. Only minor changes made to overnight lows. For Tuesday, there`s a good deal of uncertainty timing when low clouds and interspersed foggy areas from the overnight can thin out. Similar to today, will likely see continued overcast through a good part of the morning based on BUFKIT soundings, with breaks in the cloudiness becoming more apparent by the afternoon. Western extent of the wedge begins to weaken and will start to tap into the subtropical feed of moisture now across the SC/GA coast. This should help to encourage a greater coverage of showers tomorrow from along and east of the Blue Ridge during the afternoon hours. Though forecast CAPE values would support a threat of thunder, there is still a considerable amount of dry air aloft that will likely lead to shallow convective growth Tuesday. As such, think showers should again predominantly be the case versus thunder. For high temperatures, started with continuity but utilized more of the cooler raw guidance to lower temperatures a couple degrees to readings in the lower to mid 70s generally, approaching 80 in Southside and the northern NC Piedmont. If cloud cover should prove to be more stubborn, this could still be too warm by a few degrees. Confidence is moderate tonight, but is low to moderate for Tuesday. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 345 AM EDT Monday... Large scale flow pattern features highly amplified and active longwave trough over the Rockies with Bermuda High over the western Atlantic. This pattern is forecast to deamplify by the end of the week as Hurricane Michael gets a sling shot across the southeast states per interaction with the western long wave trough. Net result for our forecast area will be a wholesale increase in the rain threat from Wednesday into Thursday per deep southeast fetch of Atlantic moisture Wednesday, followed by left quadrant swipe of tropical moisture from the remnants of Michael on Thursday. Model consensus has the center of Michael passing across the Carolinas during the day Thursday with the axis of the heaviest rain passing to our southeast. That said, 48 hour rain totals (WED-THU) for our CWA are still expected to be respectable, with amounts in the 1 to 3 inch range. As the tropical system gains latitude late Thursday, surface front from the western trof is expected to pass through the forecast area Thursday night. This will begin a period of drying as it shunts the deeper tropical airmass off the east coast. Dewpoints just behind the front are progged in the 40s, so it will be a noticeable airmass change. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 400 PM EDT Monday... Upper level pattern will deflate over the weekend and into the following week as the Bermuda high gives up the October ghost. One last surge of higher dewpoint air will try to work back into the area Sunday ahead of what will be the remnants of Hurricane Sergio which is expected to get drawn into the southwestern U.S Saturday and into the base of the central CONUS long wave trough. Attm it appears the energy associated with this feature will pass through the OH valley Sunday with showers primarily to our northwest. However, with the passage of this feature it will open the door for a pattern change with the northern jet stream making dive into the central and eastern CONUS, a feature that will favor below normal temperatures across much of the central and eastern U.S. by the middle of next week. As for the details, the upcoming weekend as a whole does not look that bad...featuring dry conditions and near seasonal temperatures. Near seasonal temperatures however, means temperatures at night will be in the 40s, so it will feel noticeably cooler compared to our extended summer-like nights. By Monday, showers associated with the deepening upper level trough to our northwest are expected to move across the area. After dries out for the middle of next week, but the bottom drops out of the thermometer. Will there be frost for Wednesday or Thursday mornings of the 17/18th? Time will tell. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... As of 755 PM EDT Monday... Scattered VFR/MVFR ceilings in the 2000-4000 agl range across southwest Virginia, southeast West Virginia and northwest North Carolina this evening. IFR ceilings and MVFR fog will fill in across much of the region overnight with guidance showing high relative humidity below 850MB from 06Z/2AM through mid morning. Low Level winds increase from the southeast tonight and the resulting upslope will result in areas of MVFR drizzle and light rain, especially along the Blue Ridge and over the foothills of Virginia and North Carolina. Some river valleys west of the Blue Ridge may have LIFR fog, including at KLWB and possibly at KBCB. Ceilings will gradually lift Tuesday afternoon with isolated to scattered showers. Confidence is above average tonight and below average on timing of returning to VFR Tuesday afternoon. Extended Discussion... Showers are expected to increase in coverage by Wednesday and Thursday as tropical moisture shifts northward ahead of Hurricane Michael and a cold front moving in from the west. Rain may be heavy at times Thursday. Conditions will improve back to VFR on Friday behind the front, then VFR over the weekend. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AL NEAR TERM...AL/AMS SHORT TERM...PM LONG TERM...PM AVIATION...AL/AMS
Area Forecast Discussion
National Weather Service San Angelo TX
649 PM CDT Mon Oct 8 2018 .AVIATION... /00Z TAFS/ Look for Challenging flight weather to dominate West Central Texas tonight and much of tomorrow. As an upper disturbance moves east, across Texas, watch for a line of thunderstorms to sweep, from west to east, across West Central Texas. The HRRR brings this line into West Central Texas, from the west, around 06Z tonight. By tomorrow afternoon, this line should be exiting West Central Texas, and conditions should return to VFR. && .PREV DISCUSSION... /issued 614 PM CDT Mon Oct 8 2018/ UPDATE... Just sent a forecast update for a Severe Thunderstorm Watch for some of our central and western counties through 1:00 AM CDT Tuesday. PREV DISCUSSION... /issued 250 PM CDT Mon Oct 8 2018/ SHORT TERM... (Tonight and Tuesday) Radar this afternoon shows scattered showers and thunderstorms over Crockett County and the Concho Valley, while an area of light rain was occurring over the Heartland and Northwest Hill Country. Hi-res models indicate that this evening will not be too active with showers and storms, but considering that they have not caught on to the activity already occurring in the Concho Valley, would not be surprised if we continue to see scattered convection through the evening hours in the western half of the forecast area, and so the PoPs this evening reflect that possibility. Models remain in very good agreement with a large line of thunderstorms and showers moving through the region from west to east late tonight through early Tuesday afternoon as a front gets pushed through. The additional heavy rainfall associated with this activity will result in a higher threat of flash flooding, so the Flash Flood Watch continues through 7 am Tuesday for the Big Country, Concho Valley, Northern Edwards Plateau and Kimble and Menard counties. There`s also a threat for flash flooding through Tuesday afternoon for the Heartland counties and Mason county, so the Flash Flood Watch was expanded into those areas. In addition, there is a threat for severe thunderstorms today and tonight with any storms that develop... then a higher threat for strong to severe storms will occur as that aforementioned line of storms moves through late tonight into Tuesday morning. CAPE values of 1000-1500 J/KG and 0-6 km bulk shear 40-50 kt support rotating updrafts, and 0-1 km bulk shear of 30 kt shown by the NAM12 model indicates the potential for a few embedded tornadoes within the line of storms. Thunderstorm/shower activity should diminish from west to east across the Tuesday morning and afternoon, with mostly dry conditions likely by late Tuesday afternoon. LONG TERM... (Wednesday through Monday) The upper trough moves off to the east of the region Tuesday night with drier air filtering into West Central Texas on Wednesday. Expect mostly sunny skies on Wednesday and Thursday. PoP`s re-enter the forecast for the latter half of the week as another upper level low deepens across the southwest U.S. There remains model disagreement as to the timing of disturbances in the southwest flow aloft and the evolution of the upper low...thus will keep PoP`s in the 20-40 percent range from Thursday through the end of the week. Also, a strong cold front may dive southward into west Texas by next weekend. && .PRELIMINARY POINT TEMPS/POPS... Abilene 65 77 53 73 / 90 80 10 0 San Angelo 65 79 55 78 / 90 80 10 0 Junction 69 80 57 81 / 80 90 20 0 Brownwood 67 77 56 76 / 70 90 20 0 Sweetwater 63 75 52 73 / 90 70 10 0 Ozona 65 77 54 78 / 90 70 10 0 && .SJT WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through Tuesday morning for Callahan-Coke- Concho-Crockett-Fisher-Haskell-Irion-Jones-Kimble-Menard-Nolan- Runnels-Schleicher-Shackelford-Sterling-Sutton-Taylor- Throckmorton-Tom Green. Flash Flood Watch through Tuesday afternoon for Brown-Coleman- Mason-McCulloch-San Saba. && $$