LithiaWx Posted January 21, 2015 Share Posted January 21, 2015 I personally wouldn't throw in the towel for areas outside the mtns until tomorrow's 12z runs...way too much time to trend yet. This would be wise. Look at the last 48 hours of modeling and that should tell folks a lot can change. I'm usually quick to throw in the towel but in cases like this where there have been huge run to run changes there is still hope for some of you NC guys outside the mountains. It probably won't but the chances are much higher than zero. Link to comment Share on other sites More sharing options...
nflwxman Posted January 21, 2015 Share Posted January 21, 2015 The mountains and foothills of NC can cash in a bit here. Models can underdo dynamic cooling at this range (yes, even the euro). If you look at the GFS in the last 3 runs or so, the lower levels (925/900) are completely different each run. This means the model is struggling with dynamic cooling. If current trends hold, I would not be surprised to see a lot of low level cold air hold on on the mesoscale models during the runs tomorrow. This assumes that the GL low doesn't get stronger, and our coastal maintains the same track give or take 10 miles. Link to comment Share on other sites More sharing options...
strongwxnc Posted January 21, 2015 Share Posted January 21, 2015 The 12Z nam has a burst of SN for MBY (KFQD) at hour 48, then quickly over to rain. Close as the 950 temp is sitting at 1.0, above below 0.0. Link to comment Share on other sites More sharing options...
franklin NCwx Posted January 21, 2015 Share Posted January 21, 2015 The mountains and foothills of NC can cash in a bit here. Models can underdo dynamic cooling at this range (yes, even the euro). If you look at the GFS in the last 3 runs or so, the lower levels (925/900) are completely different each run. This means the model is struggling with dynamic cooling. If current trends hold, I would not be surprised to see a lot of low level cold air hold on on the mesoscale models during the runs tomorrow. This assumes that the GL low doesn't get stronger, and our coastal maintains the same track give or take 10 miles.unfortunately, it's the 850 temps that soar on us in the mtns. Euro starts as snow,flip to rain, then ending as snow showers flurries. Northern mtns come out almost all snow. Link to comment Share on other sites More sharing options...
nflwxman Posted January 21, 2015 Share Posted January 21, 2015 unfortunately, it's the 850 temps that soar on us in the mtns. Euro starts as snow,flip to rain, then ending as snow showers flurries. Northern mtns come out almost all snow. I agree. 850s are pretty uniformly modeled at this range. I'd argue the lower levels could hold on longer than progged, which means a bit more frozen. Link to comment Share on other sites More sharing options...
WxBlue Posted January 21, 2015 Share Posted January 21, 2015 The mountains and foothills of NC can cash in a bit here. Models can underdo dynamic cooling at this range (yes, even the euro). If you look at the GFS in the last 3 runs or so, the lower levels (925/900) are completely different each run. This means the model is struggling with dynamic cooling. If current trends hold, I would not be surprised to see a lot of low level cold air hold on on the mesoscale models during the runs tomorrow. This assumes that the GL low doesn't get stronger, and our coastal maintains the same track give or take 10 miles. This is the reason why I'm watching 4-km NAM little closely tomorrow. Not saying I favors that model the most, but 4-km NAM tends to do well for mountains around Asheville from what I've seen in two years here. Link to comment Share on other sites More sharing options...
Lookout Posted January 21, 2015 Share Posted January 21, 2015 12Z NAM is rain for everyone except the mountains (as currently progged). I seriously doubt the mountains will see 8-12 hours of freezing rain though. Most likely to be start as snow through 7am, transition to rain most of the day, then perhaps back to a wintry mix after dark. NAM is off its rocker with the ZR output (which almost never verifies in storms with these types of tracks - there's just nothing to lock in the cold air). The low is also not as wound up off the coast as GFS or Euro had (1002 mb vs. 986 mb on Euro). I don't think it's too far fetched, although it will depend a lot on elevation. Areas around 900 to 925mb/2500 to 3500 feet could see a prolonged period of freezing rain. Nam and gfs soundings are both showing easterly flow/ a decent upslope trajectory which could enhance or lock in the colder air at certain elevations/locations. It wouldn't be too unusual to see higher and lower elevations getting rain while areas around 2500 to 3500 feet get freezing rain. As I'm sure those in the mountains can testify to. The mountains and foothills of NC can cash in a bit here. Models can underdo dynamic cooling at this range (yes, even the euro). If you look at the GFS in the last 3 runs or so, the lower levels (925/900) are completely different each run. This means the model is struggling with dynamic cooling. If current trends hold, I would not be surprised to see a lot of low level cold air hold on on the mesoscale models during the runs tomorrow. This assumes that the GL low doesn't get stronger, and our coastal maintains the same track give or take 10 miles. I somehow missed this post...but i see you already nailed it. Link to comment Share on other sites More sharing options...
nflwxman Posted January 21, 2015 Share Posted January 21, 2015 This is the reason why I'm watching 4-km NAM little closely tomorrow. Not saying I favors that model the most, but 4-km NAM tends to do well for mountains around Asheville from what I've seen in two years here. Seems reasonable. Front end snow would be nice, but I could see more of an extended period of IP or ZR down that way (though not nearly as crazy as what the NAM is showing). Link to comment Share on other sites More sharing options...
Hvward Posted January 21, 2015 Share Posted January 21, 2015 This is the reason why I'm watching 4-km NAM little closely tomorrow. Not saying I favors that model the most, but 4-km NAM tends to do well for mountains around Asheville from what I've seen in two years here.Ment to comment on this when you mentioned the 4km earlier but am just now remembering... the NAM suite is tuned to simulate orographic lift the most efficently among the assortment of mesoscale models. I tend to always favor its solutions in WNC because frankly it is typically dead on within 36 hours. Beyond that it tends to get a little far fetched but in my experience it handles the peaks the best. The closeness of grid points helps but I am pretty sure it also takes into account a more complex calc equation for the elevation change. We talked about it a little in my synoptics class, but didn't go into too much detail. When forecasting short range for WNC, the 4km has proven very valuable to me with NWF and even the cutoff we had on Halloween. It performance beat the RAP & HRRR any day around WNC so I tend to give more weight to its solutions. Just my 2 cents on it, nice post wxblue. Link to comment Share on other sites More sharing options...
calculus1 Posted January 21, 2015 Share Posted January 21, 2015 Brad P with an early look at wintry weather chances for the Charlotte media market this weekend: Link to comment Share on other sites More sharing options...
superjames1992 Posted January 21, 2015 Share Posted January 21, 2015 The 12z EPS mean "snowfall" is about the same as last night's run, give or take. KCLT: 0.4" - Charlotte KAKH: 0.8" - Gastonia KGSO: 1.6" - Greensboro KGSP: 2.2" - Greenville-Spartanburg KINT: 2.6" - Winston-Salem KHKY: 4.0" - Hickory KMWK: 4.1" - Mt. Airy KUKF: 4.5" - Wilkesboro KTNB: 5.8" - Boone KAVL: 6.0" - Asheville Usual huge disclaimers, yadadada... just FWIW... Link to comment Share on other sites More sharing options...
calculus1 Posted January 21, 2015 Share Posted January 21, 2015 It's been a long time since I've seen these images on my point-and-click. Let's hope those images don't disappear as the week wears on. Link to comment Share on other sites More sharing options...
WxBlue Posted January 21, 2015 Share Posted January 21, 2015 18z NAM suites wasn't that great, I believe. Like Hvward mentioned, NAM may not be in range yet but I'm starting to lose my optimism somewhat yet again. Link to comment Share on other sites More sharing options...
calculus1 Posted January 21, 2015 Share Posted January 21, 2015 Afternoon AFD from GSP: .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...AS OF 230 PM WEDNESDAY...LATEST W/V INDICATED A DEEP TROUGH ACROSSTHE SOUTHERN FOUR CORNERS AREA. THE TROUGH IS EXPECTED TO DIG ACROSSTX ON THURSDAY...WITH A SFC LOW EXPECTED TO DEEPEN ACROSS THE NRNGULF OF MEXICO. BY LATE THURSDAY...A LARGE AREA OF DEEP MOISTURE ISFORECAST TO DEVELOP NORTH OF THE LOW CENTER...COVERING MOST OF THEDEEP SOUTH. SHORT RANGE MODELS ARE IN FAIR AGREEMENT THAT DEEPMOISTURE AND WEAK 295K ISENTROPIC LIFT WILL ARRIVE ACROSS NE GA ANDTHE WESTERN CAROLINAS DURING THE PRE DAWN HOURS ON FRIDAY. I WILLKEEP POPS LOW THROUGH MOST OF THURSDAY NIGHT...THEN QUICKLY INCREASETO CHC AROUND 8Z. SFC TEMPERATURES AT PRECIP ONSET IS FORECAST TORANGE BELOW FREEZING ACROSS THE MTNS TO MID TO UPPER 30S EAST OF THEMTNS. FORECAST SOUNDINGS INDICATE SUB-FREEZING THERMAL PROFILESACROSS THE MTNS AND I-40 CORRIDOR...YIELDING SNOW. HOWEVER...AS THEMILLER A LOW TRACKS TOWARD FL...TEMPERATURES ARE FORECAST TO WARMAROUND H8 TO 2C TO 3C ACROSS THE SOUTHERN APPALACHIANS. IT APPEARSTHAT P-TYPE WILL VARY CONSIDERABLY WITH ELEVATION AND FROM SOUTH TONORTH. BASICALLY...THE SNOW REGION WILL LIFT NORTHWARD AND WILL BEREPLACED BY AREAS OF SN/PL OR RA/PL...WITH AREAS OF FZRA ALONG THEEAST FACING SLOPES. BY FRIDAY AFTERNOON...SFC TEMPERATURES ACROSSTHE CWA ARE FORECAST TO RISE INTO THE MID TO UPPER 30S...EXCEPTALONG THE EAST SLOPE OF THE NRN MTNS. PRECIP SHOULD GENERALLY FALLAS A COLD RAIN...BUT MECHANICAL LIFTING MAY PRESERVE AN AREA OF FZRAALONG THE NRN MTNS AND ADJACENT FOOTHILLS THROUGH THE AFTERNOON. ATTHIS TIME...IT APPEARS THAT ADVISORY LEVEL ICE IS POSSIBLE ACROSSTHE CENTRAL AND NRN MTNS AND ADJACENT FOOTHILLS.FRIDAY NIGHT INTO SATURDAY...THE SFC LOW IS FORECAST TO RAPIDLYTRACK NORTHEAST ALONG THE ATLANTIC COAST. VEERING FLOW...WRAP AROUNDMOISTURE...AND CAA SHOULD RESULT IN A PERIOD OF UPSLOPE SNOWFALLALONG THE TN BORDER. BASED ON THE GFS...A STRONG AREA OF MID LEVEL Q-VECTOR DIVERGENCE WILL SLIDE ACROSS THE SOUTHERN APPALACHIANS SATMORNING. MODELS INDICATE THAT LLVL MOISTURE WILL RAPIDLY DISSIPATEBETWEEN 12Z - 18Z SAT...ENDING ACCUMULATING SNOWFALL. IT APPEARSTHAT THE OVERLAP OF SNOW SUPPORTING THERMAL PROFILES AND OPTIMAL NWWINDS WILL REMAIN SHORT...YIELDING 1 TO 2 INCHES OF SNOWFALL. CLOUDSAND POPS WILL DECREASE THROUGH THE DAY...ESPECIALLY EAST OF THEMTNS. TEMPERATURES APPEAR VERY CLOSE TO SEASONABLE VALUES.WE WILL CONTINUE TO HIGHLIGHT THE LATE WEEK WINTER WEATHER IN THEHWO. Link to comment Share on other sites More sharing options...
Marion_NC_WX Posted January 21, 2015 Share Posted January 21, 2015 18z NAM suites wasn't that great, I believe. Like Hvward mentioned, NAM may not be in range yet but I'm starting to lose my optimism somewhat yet again. I just got home from a long day on the road making deliveries...a quick glance at the data and ironically the 12z Euro looks the coldest for the Blue Ridge Escarpment in regards to 850 and 925mb temps... Link to comment Share on other sites More sharing options...
superjames1992 Posted January 21, 2015 Share Posted January 21, 2015 It's been a long time since I've seen these images on my point-and-click. Let's hope those images don't disappear as the week wears on. We can trade if you want. The 18z GFS wants to make it close for the foothills. You have 850 readouts of "0C" for the majority of the foothills early on (before they torch) with 2m temps in the mid-30s and heavy precip. Colder than the 12z run, at least, though looks like just a colder rain. Here is Mt. Airy's sounding at the time. Seems workable to me with a few changes... though I am a weenie. 2m temps are an issue, though with heavy precip they could be overdone. Maybe they aren't, though. I'm not a met or an expert. (Courtesy of AmericanWx's Model Center) Winston-Salem is about the same, too. Everyone (and I mean everyone) goes over to rain eventually, though. Link to comment Share on other sites More sharing options...
strongwxnc Posted January 21, 2015 Share Posted January 21, 2015 I just got home from a long day on the road making deliveries...a quick glance at the data and ironically the 12z Euro looks the coldest for the Blue Ridge Escarpment in regards to 850 and 925mb temps... It will not take much to give us a little in the lee. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Buddy1987 Posted January 21, 2015 Share Posted January 21, 2015 The 12z EPS mean "snowfall" is about the same as last night's run, give or take. KCLT: 0.4" - Charlotte KHNZ: 0.4" - Hendersonville KAKH: 0.8" - Gastonia KGSO: 1.6" - Greensboro KGSP: 2.2" - Greenville-Spartanburg KINT: 2.6" - Winston-Salem KHKY: 4.0" - Hickory KMWK: 4.1" - Mt. Airy KUKF: 4.5" - Wilkesboro KTNB: 5.8" - Boone KAVL: 6.0" - Asheville Usual huge disclaimers, yadadada... just FWIW... Hey James do you have what it showed for ROA? Link to comment Share on other sites More sharing options...
superjames1992 Posted January 21, 2015 Share Posted January 21, 2015 Hey James do you have what it showed for ROA? ~5", Again, I stress that these numbers are often very flawed, so I wouldn't make too much of them other than to compare them to past runs. KROA was 5.25" at 00z last night, so it's practically a wash. Link to comment Share on other sites More sharing options...
Tacoma Posted January 21, 2015 Share Posted January 21, 2015 bet the dynamic cooling will keep precip snow and sleet all day Friday in the mtns. remember this same set up about ten years ago and the NWS said the snow would change to rain in the afternoon, well that never happened it stayed snow due to the dynamic cooling and what was to be no acculmulation turned out to be 9 inches when all was said and done. hoping this happens this weekend. Link to comment Share on other sites More sharing options...
Ollie Williams Posted January 21, 2015 Author Share Posted January 21, 2015 HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BLACKSBURG VA 300 PM EST WED JAN 21 2015 NCZ003-019-VAZ013-014-016-017-022-032-033-222000- SURRY-WILKES-PULASKI-MONTGOMERY-CARROLL-FLOYD-ROANOKE-PATRICK- FRANKLIN- 300 PM EST WED JAN 21 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL NORTH CAROLINA...NORTHWEST NORTH CAROLINA...SOUTHWEST VIRGINIA AND WEST CENTRAL VIRGINIA. .DAY ONE...THIS AFTERNOON AND TONIGHT. HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY. A MIX OF SLEET AND SNOW WILL SPREAD ACROSS THE AREA BY MIDDAY FRIDAY AND CONTINUE BUT INCREASE IN INTENSITY FRIDAY NIGHT. BY SATURDAY MORNING...RAIN...SLEET...FREEZING RAIN...OR SNOW IS EXPECTED. AN AVERAGE OF LESS THAN ONE INCH OF SNOW AND SLEET IS POSSIBLE DURING THIS TIME FRAME. A LIGHT COATING OF ICE IS POSSIBLE NEAR THE CREST OF THE BLUE RIDGE. Link to comment Share on other sites More sharing options...
wncsnow Posted January 21, 2015 Share Posted January 21, 2015 In the past I would have a lot of optimism about this setup for the mountains and adjacent foothills due to the track of the low and climo, but lately marginal cold air events like this hasn't worked out, even for higher elevations.. Link to comment Share on other sites More sharing options...
Buddy1987 Posted January 21, 2015 Share Posted January 21, 2015 ~5", Again, I stress that these numbers are often very flawed, so I wouldn't make too much of them other than to compare them to past runs. KROA was 5.25" at 00z last night, so it's practically a wash. Thanks man appreciate it. I am fully aware of these numbers from past events. If I could even get half id be ecstatic. Link to comment Share on other sites More sharing options...
jacobr57 Posted January 21, 2015 Share Posted January 21, 2015 Anyone have an analysis of the 18Z GFS? Link to comment Share on other sites More sharing options...
ILMRoss Posted January 21, 2015 Share Posted January 21, 2015 Anyone have an analysis of the 18Z GFS? Wasn't able to read too much into it, but not much change from the 12z. Temps are still pretty doggone warm for snow anywhere in this region, even in the mountains. Link to comment Share on other sites More sharing options...
DaculaWeather Posted January 21, 2015 Share Posted January 21, 2015 Ment to comment on this when you mentioned the 4km earlier but am just now remembering... the NAM suite is tuned to simulate orographic lift the most efficently among the assortment of mesoscale models. I tend to always favor its solutions in WNC because frankly it is typically dead on within 36 hours. Beyond that it tends to get a little far fetched but in my experience it handles the peaks the best. The closeness of grid points helps but I am pretty sure it also takes into account a more complex calc equation for the elevation change. We talked about it a little in my synoptics class, but didn't go into too much detail. When forecasting short range for WNC, the 4km has proven very valuable to me with NWF and even the cutoff we had on Halloween. It performance beat the RAP & HRRR any day around WNC so I tend to give more weight to its solutions. Just my 2 cents on it, nice post wxblue. Good to know, thanks for that bit of info. Link to comment Share on other sites More sharing options...
deltadog03 Posted January 21, 2015 Share Posted January 21, 2015 This could be one of those things where the 5k tops could be rain/snow mix and down around 2-3k there is some ZR as cold air gets trapped down there. I Think thats why the models are showing some "PINK" vs "BLUE" at times for Fri. That would be a first for me, I don't know If I have seen that before, where its raining up top (5k or so) and some ZR/IP down at t 2-3k Link to comment Share on other sites More sharing options...
franklin NCwx Posted January 21, 2015 Share Posted January 21, 2015 This could be one of those things where the 5k tops could be rain/snow mix and down around 2-3k there is some ZR as cold air gets trapped down there. I Think thats why the models are showing some "PINK" vs "BLUE" at times for Fri. That would be a first for me, I don't know If I have seen that before, where its raining up top (5k or so) and some ZR/IP down at t 2-3kthat doesn't happen very much at all southwest of the balsams. Asheville east and ne can have freezing rain like that. But usually not once you head towards Waynesville, and Franklin. Link to comment Share on other sites More sharing options...
deltadog03 Posted January 22, 2015 Share Posted January 22, 2015 Hey gang, new weather video is up! Talking about the storm for Thursday, Friday and Saturday, PLUS the clipper and what that potential could do for us. Then** we look ahead toward the **POTENTIAL** for another storm as we get closer to D10-11 *superbowl Sunday* The TRENDS are very promising and encouraging, but obviously its quite a bit of ways away. We shall see, but I like the "look" so far. Thanks for watching! https://www.facebook.com/ChriswxmanSimmons Link to comment Share on other sites More sharing options...
Buddy1987 Posted January 22, 2015 Share Posted January 22, 2015 0Z nam underway. Lets see what shes got up her sleeve tonight. Through 9hr the northern vort diving through Utah may be a smidge stronger, however surface reflection doesnt indicate any difference precip wise. Link to comment Share on other sites More sharing options...
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