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NavarreDon

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  1. Another busy day at work for me! I know there is a dedicated obs thread that you folks will want to use. Please post or re-post in this thread. The dedicated one is just to much for me me to wade thru. Good luck to all you folks with a special shout out to the old timers Joe, Jason, Mark, Thomas, & anyone else I forgot!, lots of pics and vids please!
  2. Just wanted to post MOB's thoughts on downstream convection and the "Fire Hose". NEAR TERM /Now Through Sunday/...There are not a lot of changes from the previous forecast thinking. The primary forecast challenges continue to revolve around the upcoming heavy rain event and the associated potential for flooding impacts across our region, as well as on the potential for an isolated severe storm or two near the immediate coast Saturday into Saturday night. An upper level trough located near the vicinity of southwest Arizona and northern Baja this afternoon is forecast to translate eastward toward west Texas into Saturday morning, before lifting northeastward toward the Mississippi and Tennessee Valley region through Saturday night. Surface low pressure will develop over southeast Texas tonight and track eastward, likely paralleling the immediate northern Gulf Coast through Saturday night. Deep moisture ahead of a shortwave trough translating over Lousiana and Mississippi will spread into northwestern portions of our area tonight, and we will carry a chance of rain over these zones, with the best chance mainly focused northwest of I-65. Short range model guidance remains in good agreement with bringing large scale ascent into our forecast area ahead of the aforementioned approaching upper level trough and surface low pressure system Saturday into Saturday night. The potential for locally heavier rainfall will spread into southeast Mississippi and interior southwest Alabama Saturday morning, where likely to categorical POPs have been indicated between 6 AM and noon. Short range and available high resolution guidance then continues to indicate that heavy rain will spread across the remainder of the forecast area Saturday afternoon into Saturday evening, with potential QPF amounts of 2 to 4 inches with locally higher totals possible across much of the region. Some short range and high resolution guidance continues to signal higher QPF amounts impacting portions of southwest/south central Alabama and the western Florida panhandle Saturday afternoon and evening, including locations that received very heavy rainfall last weekend. Given the saturated soils/antecedent conditions, we have opted to issue a Flash Flood Watch for locations roughly south of a Mobile to Andalusia line for Saturday afternoon and evening. The severe weather potential otherwise continues to look very limited/marginal, and mainly across locations along the immediate coast where very weak instability may penetrate inland ahead of the approaching low pressure system, coincident with strong low level and deep layer shear. We will need to monitor for an isolated severe storm capable of damaging wind gusts or a brief tornado along the coast. A high risk of rip currents will exist along area Gulf beaches from Friday night through Sunday night. High surf, and minor coastal flooding will also be possible Saturday afternoon into Saturday night.
  3. Joe, I’ll bet you a bottle of Makers you exceed your predictions! .
  4. Guys I’m not one for hyperbole & things are always fluid but, this has all the makings of an amazing event! I hope all of you exceed your expectations and we’re able to reference the December 18 storm for years to come!!! Good luck and I’ll be living vicariously through all of you. .
  5. Been busy at work but MOB is not super worried about it down this way. .
  6. Again to piggy back on what HT has been say for the past several days. Here is MOB's short term for our area. This is the fire hose he has been talking about. In this type of set up the QPF transports up to your region. .SHORT TERM /Saturday Through Sunday night/...Widespread rainfall spreads from west to east across the region Saturday through Saturday night as a surface low pressure system moves eastward along the coast from LA into the Western FL panhandle. Deep layer moisture, with precipitable water values consistently advertised by the GFS to climb to around two inches, coupled with large scale forcing for ascent should lead to periods of heavy rainfall. Widespread rainfall totals of 2 to 4 inches with isolated totals as high as 6 inches remain possible. Current trends indicate that the heaviest rainfall will fall over Southeast Mississippi during the late morning hours tapering off during the early evening hours, Alabama counties West of the I-65 corridor during the afternoon through early evening and Western Florida Panhandle counties and Alabama counties East of the I-65 corridor mid to late afternoon into the late evening hours. Concerns for potential flooding remain especially over the area southeast of a Mobile to Andalusia line due to last weeks heavy rains last week keeping the soils in this area relatively moist. Heavy rain fall occurring within short period of time is possible which could create areas of flash flooding. Furthermore, widespread rainfalls of 4 inches could lead to minor and possibly moderate river flooding in this area. A Flash Flood Watch may be issued for this area in the next 12 hours. Based on the current forecast track of the surface low, a marginal severe threat will exist along the coast just ahead of the surface low in the warm sector. The primary risks being brief tornadoes and damaging straight line winds Saturday and Saturday night. A high risk of rip currents will exist along area Gulf beaches from Friday night through Sunday night. High surf, and minor coastal flooding will also be possible Saturday afternoon into Saturday night. As the region remains under the base of the upper level trough, a few sprinkles and a lingering chance of some light rain will continue Sunday through Sunday evening/night time frame. /08
  7. It really doesn't get much better than this! I have no dog in this fight so to speak & I get really excited looking at these 2 side X side!!!
  8. I did want to post this and just say remeber to take a deep breath when things don't go your way & there's still time for change. Things may change again but the chase is a huge part of the fun. Try to make sure your highs aren't to high & your lows aren't to low.
  9. Nice!....giddy up!!! .SHORT TERM /SATURDAY THROUGH MONDAY/... As of 330 AM Friday: Confidence is high enough on significant snow/wintry precip in the heart of the expected cold air damming, that after collaboration with WFO RNK, portions of the watch have been upgraded to a winter storm warning. The rest of the watch will be left as is, as there is still some time to fine tune details. Overall, no big surprises in the 00z guidance. If anything, they`ve trended a little wetter. Adequate QPF for winter storm warning criteria accums is not an issue. The two biggest concerns are the evolution of a warm nose above the CAD, and the sfc-based warm layer around the periphery of the wedge. These will determine the p-type thru the event. I opted to take a 50/50 blend of the GFS/NAM profiles. The NAM has the much stronger warm nose, bringing it even into the central NC mountains for a time on Sunday. So precip should start expanding north and east across the forecast area during the day on Saturday. Thermal profiles suggest most of the precip will start out as rain, except in the central and northern mountains and adjacent foothills in NC. By early Saturday evening, CAD should be really strengthening across the Piedmont, as precip rates will be at their highest and the ~1036 mb parent high reaches PA. The wedge looks to advect enough cold/dry air to wet-bulb temps down into the upper 20s to mid 30s across the entire Piedmont by daybreak Sunday. This will be about the time the warm nose will punch in from the east, resulting in a wintry mix of rain/sleet/freezing rain. Meanwhile, most of the I-40 corridor looks to remain all snow. The sfc low will track from the FL panhandle east to off the Georgia coast by Sunday aftn. The NAM has a dry air punching in from the southwest, which could cut off ice nuclei activation and turn snow/sleet to freezing rain/drizzle. However, the GFS/ECMWF/CMC all seem to keep deeper moisture within a developing deformation zone thru Sunday night. For now, I keep ice nuclei active thru the event. This allows snow totals to continue to pile up. Finally, Sunday night thru Monday, as the sfc low deepens off the Carolina coast, cold air spills in behind the circulation and should erode the warm nose aloft. Thermal profiles turn into ra/sn, with some snow possible across even in the southern Upstate. However, precip rates should be very light by this point. Temps will hover mainly in the 28-35 deg range Sunday thru Sunday night, then rebound slightly on the back side of the system on Monday to the upper 30s to lower 40s. We have expanded the watch to include the GA and SC mountains, along with a tier of zones from Pickens to York County in SC, where climatologically in CAD events should get higher wintry accums. While the rest of the GA and SC Piedmont is still too low confidence for a watch, but may need an advisory once the event is within 24 hours. Given the upward trend in QPF. Impacts from the combination of what is expected to be a very wet snow, and icing in some areas, look to be significant. Very windy conditions are expected Saturday night and most of Sunday, which makes falling trees and power lines likely.
  10. URGENT - WINTER WEATHER MESSAGE National Weather Service Greenville-Spartanburg SC 420 AM EST Fri Dec 7 2018 ...MAJOR WINTER STORM TO IMPACT THE REGION THIS WEEKEND... .Cold high pressure along the East Coast will interact with a moist low pressure system moving out of the Gulf of Mexico Saturday night into Sunday. Moderate to heavy precipitation will fall as a mixture of snow, sleet, and freezing rain across the region. Accumulations are expected to be greatest in western North Carolina. NCZ033-049-050-053-064-065-501-503-505-507-509-071730- /O.UPG.KGSP.WS.A.0005.181208T1800Z-181210T1700Z/ /O.NEW.KGSP.WS.W.0006.181209T0000Z-181210T1700Z/ Avery-Yancey-Mitchell-Buncombe-Transylvania-Henderson- Caldwell Mountains-Burke Mountains-McDowell Mountains- Rutherford Mountains-Polk Mountains- Including the cities of Ingalls, Banner Elk, Newland, Swiss, Burnsville, Celo, Micaville, Ramseytown, Busick, Spruce Pine, Poplar, Asheville, Brevard, Cedar Mountain, Little River, Hendersonville, Fletcher, Dana, East Flat Rock, Tuxedo, Etowah, Patterson, Jonas Ridge, Ashford, Sugar Hill, Woodlawn, Old Fort, and Saluda 420 AM EST Fri Dec 7 2018 ...WINTER STORM WARNING IN EFFECT FROM 7 PM SATURDAY TO NOON EST MONDAY... * WHAT...Heavy mixed precipitation expected. Total snow accumulations of 10 to 16 inches and ice accumulations of around one tenth of an inch expected. * WHERE...Portions of western North Carolina, including the upper French Broad Valley to the Northern Mountains and Northern Foothills. * WHEN...From 7 PM Saturday to noon EST Monday. * ADDITIONAL DETAILS...Travel could be very difficult to impossible. Road conditions could deteriorate as early as Saturday evening, with highway travel continuing to be impacted through early next week. Visibility may drop to less than a half mile during periods of heavy snow. Widespread, prolonged power outages are possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning means significant amounts of snow, sleet and ice will make travel very hazardous or impossible.
  11. I love GSP but they are taking a brutal beating on twitter for this map. I'm willing to bet this one may go into the closet, never to be seen again! On a more serious note I have concerns that some places (eastern facing & above 3500') may be close to blizzard conditions during the event at times. I really feel like you will see some different maps, forecasts overnight & especially tomorrow from the crew in Greer if things hold the way they are.
  12. Wanted to say a couple things about GSP. 1st off you have different Mets writing AFD’s and they have different perspectives. While they collaborate the lead forecaster has the most input. 2nd. This is essentially their 1st call map and will change at least 4 more times before the storm arrives. 3rd they are some of the best in the business but are human and prone to error (anyone remember the farmer reference in the AFD from the Christmas 2010 storm). I would much rather have them bust calling for less and getting more than vice versa. Take a breath and let’s see where it goes. .
  13. As long as I’ve been on this board some people hug each model run. Here’s a friendly psa. Watch trends not individual model runs. No reason to cliff dive now. As far N FB river valley goes after living there for 11 years I will be stunned if their is freezing rain issues or major dry slotting. Not saying it won’t happen but I think it’s unlikely. Take a breath, the chase is part of the fun! .
  14. I realize we're all big boys & girls with the capability to find it own our own but the ST disco from GSP is well......simply stunning! It needs to be posted for posterity. Even a mention of the B word! .SHORT TERM /FRIDAY NIGHT THROUGH MONDAY/... As of 355 AM EST Thursday: High confidence that a nearly ideal synoptic set up for widespread and significant winter weather will commence across the forecast area this weekend and possibly continue into early next week. The highest in significant winter weather is placed across the mountains foothills and NC Piedmont along and north of I-40 where snow is expected to be the dominant precipitation type, although periods of sleet and freezing rain are also likely, especially outside of the mountains. Moderate confidence for significant winter weather exists in the SC/NC Piedmont along and north of I-85 and south of I-40 mainly east of I- 25. South of I-85 is not out of the woods with periods of moderate to heavy ice and/or snow possible, but rain is expected to mix in most often here, likely limiting ice/snow accumulations and related impacts. The expected overall synoptic setup has not really changed much for several days, although model guidance has fairly uniformly tracked track of the winter storm a bit further south and therefore leading to snow and mixed precip types becoming more likely a bit further south. A key to the upcoming winter storm is that cold air will be locked in place across the region as confluence aloft ahead of the system maintains a 1030+ mb W-E elongated sfc high pressure system to our north with cold air damming (CAD) persisting through most of the event. Good model consensus shows sfc low pressure riding along the fringe of the strong high, initially along the Gulf Coast Saturday before riding along or just off the Southeast Coastline while intensifying Sunday. This setup will bring light to moderate precip overspreading much of the sometime Saturday afternoon or evening before becoming heavy at times overnight into Sunday. The latest NAM indicates very dry air courtesy of the CAD possibly delaying precip onset, especially across NC foothills, Piedmont and northern mountains. A strong low level jet of 40+ kt is expected to push through the region Sunday bring breezy conditions to many location and gusty winds to the mountains above 3K or 4K feet where wind gusts in excess of 40 mph are likely. This combined with period of heavy snow may support at least brief blizzard conditions, especially across east facing mountains. The strong low level jet will also support an elevated (700-800mb), but now somewhat cooler warm nose which will likely increase the icing threat which model guidance and climatology would suggest would change somewhere between the I-85 and I-40 corridors, lasting at least 3-6 hours. The timing of the change over is likely sometime late Sunday night though early evening and would like be limited across the mountains, although sleet and freezing rain may mix in at times during this period, especially south of I-40. The CAD will likely gradually dissipate late Sunday into Monday but be replaced by cold air filtering in behind the storm. Any ice should be large over during this time with snow the predominate type area-wide, except during the afternoon when rain may mix in at times outside of the mountains mainly into the Upstate of SC and northeast GA. A deformation zone with banding precip is possible during this time, but there is still some uncertainly where exactly sets up and how much precipitation we may see. The bottom line is the additional snow is possible just about anywhere during this time. Melted snow/ice or liquid precip storm total amounts continue to be around 2 inches across most of the forecast area with local amounts approaching 3 inches possible south of I-85 and across higher east facing mountains due to upslope enhancement. Early estimates continue to place snow amounts between 10 and 20 inches across the mountains, foothills Piedmont northwest of I-85. Local 20+ amounts are possible across higher east facing mountain and foothill locations. Dangerous freezing rain and sleet accumulations in excess of one half an inch continue to be possible with the high totals and therefore impacts between I-85 and I-40 outside of the mountains. Although latest model trends suggest areas closer to I-85 might have the most cause for concern. the bottom line is that a potentially very dangerous winter storm looms for much of the forecast area this weekend. And as the day shift yesterday put it, this could be a once-in-a-generation event for areas that experience mostly snow and ice. Now is the time to prepare. Finish preparations by Friday as if this storm speeds up Saturday may be too late, especially for the Upstate of SC into northeast GA.
  15. And now the Disco has entered the ST, it just gets better & better. I even see the B word! Hold your socks fellas cuz this one may knock your shoes off!!! .SHORT TERM /FRIDAY NIGHT THROUGH MONDAY/... As of 355 AM EST Thursday: High confidence that a nearly ideal synoptic set up for widespread and significant winter weather will commence across the forecast area this weekend and possibly continue into early next week. The highest in significant winter weather is placed across the mountains foothills and NC Piedmont along and north of I-40 where snow is expected to be the dominant precipitation type, although periods of sleet and freezing rain are also likely, especially outside of the mountains. Moderate confidence for significant winter weather exists in the SC/NC Piedmont along and north of I-85 and south of I-40 mainly east of I- 25. South of I-85 is not out of the woods with periods of moderate to heavy ice and/or snow possible, but rain is expected to mix in most often here, likely limiting ice/snow accumulations and related impacts. The expected overall synoptic setup has not really changed much for several days, although model guidance has fairly uniformly tracked track of the winter storm a bit further south and therefore leading to snow and mixed precip types becoming more likely a bit further south. A key to the upcoming winter storm is that cold air will be locked in place across the region as confluence aloft ahead of the system maintains a 1030+ mb W-E elongated sfc high pressure system to our north with cold air damming (CAD) persisting through most of the event. Good model consensus shows sfc low pressure riding along the fringe of the strong high, initially along the Gulf Coast Saturday before riding along or just off the Southeast Coastline while intensifying Sunday. This setup will bring light to moderate precip overspreading much of the sometime Saturday afternoon or evening before becoming heavy at times overnight into Sunday. The latest NAM indicates very dry air courtesy of the CAD possibly delaying precip onset, especially across NC foothills, Piedmont and northern mountains. A strong low level jet of 40+ kt is expected to push through the region Sunday bring breezy conditions to many location and gusty winds to the mountains above 3K or 4K feet where wind gusts in excess of 40 mph are likely. This combined with period of heavy snow may support at least brief blizzard conditions, especially across east facing mountains. The strong low level jet will also support an elevated (700-800mb), but now somewhat cooler warm nose which will likely increase the icing threat which model guidance and climatology would suggest would change somewhere between the I-85 and I-40 corridors, lasting at least 3-6 hours. The timing of the change over is likely sometime late Sunday night though early evening and would like be limited across the mountains, although sleet and freezing rain may mix in at times during this period, especially south of I-40. The CAD will likely gradually dissipate late Sunday into Monday but be replaced by cold air filtering in behind the storm. Any ice should be large over during this time with snow the predominate type area-wide, except during the afternoon when rain may mix in at times outside of the mountains mainly into the Upstate of SC and northeast GA. A deformation zone with banding precip is possible during this time, but there is still some uncertainly where exactly sets up and how much precipitation we may see. The bottom line is the additional snow is possible just about anywhere during this time. Melted snow/ice or liquid precip storm total amounts continue to be around 2 inches across most of the forecast area with local amounts approaching 3 inches possible south of I-85 and across higher east facing mountains due to upslope enhancement. Early estimates continue to place snow amounts between 10 and 20 inches across the mountains, foothills Piedmont northwest of I-85. Local 20+ amounts are possible across higher east facing mountain and foothill locations. Dangerous freezing rain and sleet accumulations in excess of one half an inch continue to be possible with the high totals and therefore impacts between I-85 and I-40 outside of the mountains. Although latest model trends suggest areas closer to I-85 might have the most cause for concern. the bottom line is that a potentially very dangerous winter storm looms for much of the forecast area this weekend. And as the day shift yesterday put it, this could be a once-in-a-generation event for areas that experience mostly snow and ice. Now is the time to prepare. Finish preparations by Friday as if this storm speeds up Saturday may be too late, especially for the Upstate of SC into northeast GA.
  16. Great write up HT, very detailed and appreciated. I just want to piggy back on the fire hose part of the write up. This is the disco from MOB for our area. It will give you some insight into the downstream part of the storm. SHORT TERM /Thursday night Through Saturday night/...A mid to upper level zonal flow pattern will persist across the central Gulf Coast region Thursday night through Friday, while surface high pressure continues to ridge over the southeastern U.S. Cloud cover will be on the increase across our forecast area through Friday, but the forecast looks to remain dry as deeper moisture remains to our west and northwest through Friday afternoon. Cool temperatures continue with lows Thursday night in the 30s over the interior, with lower to mid 40s near the immediate coast. Highs Thursday should moderate into the upper 50s to the lower 60s. The next upper level trough is forecast to move from the Desert Southwest Friday evening to the vicinity the Mid-Mississippi and Tennessee Valley region by Saturday night. An associated area of surface low pressure should track eastward along the coastal portions of Louisiana, Mississippi, Alabama, and northwest Florida along a frontal boundary Saturday into Saturday night. Deep layer ascent will spread into western and northwestern portions of our forecast area Friday night into Saturday morning, then across the remainder of the CWA Saturday afternoon into Saturday night ahead of the approaching trough axis and low pressure system. Widespread rain showers will impact the region Saturday into Saturday night, and will keep categorical POPs in the 80-90% range during this time frame. The primary concern with this event will be heavy rainfall, as the latest medium range guidance continues to advertise widespread 2-3 inches of rain over much of the region, but there could be some localized amounts of 4-6 inches near the coast which will be within a region of stronger forcing and higher precipitable water values. Localized flooding/flash flooding may become a concern near the coast, where soils remain relatively saturated from the rainfall event last weekend. The severe weather potential still remains more uncertain and primarily relegated to areas near the immediate coast. There will be plentiful deep layer and low level shear with this system, but instability remains highly uncertain. A severe threat could eventually impact locations near the AL coast and portions of the northwest Florida panhandle Saturday afternoon into Saturday night, where there are still some signs of a weak warm sector and associated weak instability penetrating inland over this portion of the area ahead of the low pressure system, and will continue to monitor this potential over the next 2-3 days. .
  17. Gonna be a good one for you Jason! Wouldn't trade the beach move for anything but, times like these I wish I was still on New Stock Rd! You're right it's great to see 85 sticking his pretty mug in this thread!
  18. Good Morning folks! When I read this LT disco from GSP it does nothing but tell me you guys are in for some early season fun.....buckle up!!! .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... As of 350 AM Wednesday: Above normal confidence exists for a significant winter storm across at least portions of the forecast area this weekend and possibly lingering into early next week. This is due to unusually good consistency between models and from run to run really for several days now despite the storm system now pushing into the southwest U.S. This has occurred in the past, especially for unusually significant storms. This storm may fall in the unusual significant category, especially across the mountains and foothills as it seems to have all the necessary ingredients for a high impact winter storm. This being said, below average confidence continues in the exact forecast details and related potential impacts as relatively minor shifts to the storm track or strength can lead to significant changes where and how long wintry precip sets up. High pressure will continue to nose into the Mid-Atlantic states Friday night behind the cold front before wedging down east of the mountains during the day Saturday, supporting colder and drier low levels, ahead of this weekends storm system. The storm is expected to slide along the Gulf of Mexico coastline Friday into Saturday before turning the corner near the Southeast U.S. coastline by late in the day Sunday. Increasing mid to high level clouds late Friday night into Saturday will likely assist the CAD in locking in cold temperatures with highs only in the 30s to around 40 or 15-20 degrees below normal. Increasing moist southerly flow enhanced by isentropic lift up and over the established cold dome at the surface will support increasing precip changes from the southwest through the day. Saturday night into Sunday may be the most significant precipitation of the storm as strong southeasterly 30 to 40 kt 850 mb winds originating from the Gulf of Mexico enhance moisture transport. This flow is also perpendicular to the cold dome continue to be supported by a 1030+ mb high to the north as well as the perpendicular to the mountains which will enhance lift and therefore precipitation intensity and totals across the region. Precipitation types across the region is the most challenging aspect of this storm as it appears areas along and northwest of I-85 will likely see at least some wintry precip to the mountains which may experience mostly snow and ice. Warmer air aloft (warm nose) may try to work into the region with the heaviest precipitation Sunday into Sunday evening leading to greater ice/rain potential at least briefly across the region. The duration of precipitation types will be critical as current liquid precipitation continues to fall in the 1- 2 inch range with uplope areas possibly seeing up to 3 inches. The take home message is that were are potentially dealing with a dangerous storm with significant snow and ice accumulation now likely across the mountains and foothills and possible anywhere along and northwest of I-85. Early estimates place a potential for snowfall amounts in excess of 6 inches across the mountains and NC foothills with ice accumulations possibly in excess of 1/2 of an inch across NC foothills/piedmont, especially north of I-40. Now is the time to put your winter weather plan together and prepare for this potentially significant upcoming winter storm. The low is expected to intensify fairly rapidly off and slow down or stall off the NC/VA coast Monday guidance continues to show a reinforcing short wave diving into the trough. This may support enhancement of precipitation on the backside of the storm early next week, leading to potentially additional wintry precip across the region.
  19. I'm not implying they are similar events but, during the December 2009 storm we started as snow then went to rain then back to heavy snow. We ended up with 16" + 2" more of flow snow on the back side for a total of 18" in Weaverville. Could there be mixing.....sure. With the QPF amounts shown on most of the guidance how relevant can it be? I guess if 3' is your goal you're out of luck. If 12"+ makes you happy you'll have grins galore!!!
  20. Joe, I expect this forecast to be fine tuned many times before the event. At this point GSP is covering all the bases. I hope you've made a Woodfin run or are able to in short order. If I didn't have to work so damn much I'd be hitting you up for room and board during the event!!! Highly likely you will be giddy as a schoolgirl on a first date for this one!
  21. For some if the old timers on the board Robert (Foothills) says their are some details as usual to get worked out but........This one has the potential to be truly historic for the Mnt. region!
  22. Here ya go folks! .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... As of 230 PM Tuesday: Still expecting a potentially significant winter storm starting Saturday and possibly continuing into Monday. However, the models continue to waffle a bit on the details. The latest forecast blends the 12z ECMWF and GFS, which have both trended a little south with the sfc low track across the Gulf Coast/Deep South, resulting in slightly colder thicknesses. The 12z guidance has generally trended upward on QPF, as has WPC. This looks like a fairly heavy QPF event, if trends hold. The WPC days 4-7 winter outlook now shows 70-90 percent chance of winter storm warning criteria ice/snow accumulations across portions of the NC mountains from 12z Saturday to 12z Sunday, with additional amounts likely from 12z Sunday to 12z Monday. One of the reasons the models have trended wetter is that they show a strong secondary shortwave that dives in behind the main southern stream wave on Monday. This keeps a deformation zone over the area thru the day on Monday, with thicknesses supporting mostly snow. The set up still looks the same...a split flow regime across the western CONUS with confluent flow and a northern stream trough in the East. Sfc high pressure of 1032-1038 mb elongated east-west across the Great Lakes supports classic/strong CAD. As the southern stream wave ejects from the Four Corners region to the Southern Plains, strong upglide and frontogenesis coupled with upper level divergence should spread precip into the area sometime on Saturday. The models continue to delay the onset a little with each run. The brunt of the precip and strong CAD looks to be Saturday night thru Sunday (again these times may slip further). The 12z ECMWF has a very strong easterly jet on the north side of the low, resulting in strong moisture transport. So this has a lot going for it, QPF-wise. As for temperatures/thicknesses, it`s still so borderline with sfc wetbulb temps and warm nose position and strength. Went with a blend of 12Z ECMWF/GFS for the partial thickness nomogram technique. Still looks like a wintry mix for much of the area, with possibly heavy snow in the mountains and northern Foothills. Depending on the strength of the CAD, Freezing rain could also be a bigger concern across the Piedmont. Hopefully, things start converging on a solution as we get closer to this weekend. But anyway, now is the time to put your winter weather plan together to be prepared for this upcoming and future potential winter storms.
  23. No matter what the outcome is with this system, staring at this map is hypnotic & makes me dizzy! You may never see something like this again in your lifetime.....32" @ KAVL is just mind boggling!
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