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Found 32 results

  1. Advertised cold weather pattern should commence around December 6 and work in here well by Dec 7-8. I would like to limit precipitation charts to within 5 days. The exception is NWFS for the Mountains and Plateau, which is more skillful because it does not require an exact storm track. Discussion of favorable pattern (odds) is OK and even encouraged past Day 5, just no charts please. The good news is SER intrusions have departed recent model runs. Oh there is always a trade-off in the South. Northwest flow in the Plains gets as close as the Mississippi Valley at times, which opens the door for mild interludes within the cold pattern. Even with some variability the cold 6-15 day period carries high confidence. I put it near 85% in the 6-10 day; better than 50% in the 11-15 day. Still a slight risk that Day 10 mild interlude is the end, but I think cold reloads for the 11-15 day. Near textbook upper level pattern really lacks surface source region support though. Alaska and most of Canada cold is not strong. Manitoba and Ontario will get cold but it barely gets colder points north. Quebec looks strong but it's not our trajectory. Sustained cross polar flow from Siberia is required for impressive cold this time. A few days would not be enough since temps are AN in Alaska. Northern US snowpack deficit is a gaping hole in the equation for record or even just strong cold. So I think the 6-15 day will be cold enough to put one in the Holiday mood, but not particularly impressive. First front (6-10 day) may under-achieve as usual coming into a warm regime. Second front (11-15 day) should verify so long as it actually gets in here (>50% chance). If the upper level pattern holds through weeks 3-4, we might be able to talk about stronger cold anomalies. Right now looks like some lows in the 20s first half of Dec. If looking for teens or colder, more time in the cold pattern is required. A minority of ensemble members show a decent pattern for winter precipitation in the 11-15 day. Others are cold but dry. A smaller minority is too warm. I am looking for an active southern branch through the Deep South, not NW flow and zero SER attempts.
  2. I need help figuring out how to calculate Dcape, "Effective"SRH (or SRH in general), and "Effective"BWD.
  3. As we enter into the late period of the month and we are officially into spring time, things look to bounce around as the norm goes, around this time of the year. From a high of 70 today to a high of 50 tomorrow. Got to love spring in the mountains.
  4. The models keep showing this as a possible threat. Jeff mentions his reasoning for the ice potential in the winter pattern thread. A very strong cold front will sweep through the area overnight Saturday into Sunday causing crashing temps. Most models agree there will be moisture of some amount behind the front. There could also be freezing issues due to the heavy amounts of water left by the rain. In addition to the totals of ice below. Models also show some degree of sleet or snow. I believe the Euro showed an inch or so in a good portion of the area. The NAM shows some snow in parts of East Tennessee. The GFS had a couple of runs showing it too. I believe some of their maps may be incorporating sleet into their snow total maps. The worst case scenario is the Canadian, crippling ice storm for a good portion of the Valley on the 12z run. The Canadian was the first to show this possibility and hasn't wavered from it for days on end. The GFS is much more localized with freezing rain totals. The NAM splits the difference.
  5. While it is the 4km NAM, that model along with the less, but still notable 12km NAM are both showing a decent chance of severe weather and potentially a tornado threat in Alabama and surrounding areas on Thursday, March 24th. It seems right now, if this setup wants to be more significant, the surface low should want to slow down a bit so surface winds would be more backed in the area. Also, CAPE values generally range from around 1000 J/kg on the 12km NAM/GFS to 1500-2000 on the 4km NAM. Regardless of this, the 4km NAM shows discrete supercells in central Alabama Thursday afternoon.
  6. Spring in the Valley 2016

    Since met winter is coming to a close it's time for the Spring 2016 Tennessee Valley Edition.I changed the wording on the Nina thread to just Nina and took out the spring discussion.This way there is no confusion with two different topics.
  7. Severe Storms April 9

    Could be severe weather dinner theater from Memphis north to Paducah this evening. Couple isolated cells may develop ahead of the main line. While Illinois may enjoy more turning winds with height, and a lovely retreating boundary, heating is better in the Mid South. Looks like some sort of differential heating boundary or moisture surge from eastern Arkansas into far western Tennessee. While it could be a focus for cells ahead of the line, most hi-res guidance just shows a big cluster of storms developing. Very latest 15Z HRRR shows a cluster in the Delta actually cutting off flow into the main line and even the above boundary. Previous HRRR and 12Z hi-res NAM had better inflow for the main line of storms. Looks like mainly wind and hail to me. I agree with the low tor probs from SPC for the Mid South. Maybe we will see nice photos of a shelf cloud over downtown Memphis this evening.
  8. Looks like a fairly active pattern over the latter part of this week and perhaps early next week particularly for the western side of our region.....Obviously severe is always a short fuse situation but it was most interesting to see SPC start actually using Day 6 severe outlooks (and potentially beyond).
  9. From looking at models and extended forecast discussions, it appears that severe weather is possibly Wednesday, April 1st through Friday, April 3rd. SPC has outlined a slight risk for portions of Eastern KS, Northwestern MO, Eastern NE, Western IA, Extreme Southeastern SD, and Extreme Sounthern WI for Wednesday. They have also outlined 15% areas for D4 and D5 in areas of Dixie Alley for Thursday and Friday. Opinions?
  10. What are your thoughts on Day 1 MRGL, SLGT and MDT risk severe outlooks issued by the Storm Prediction Center in New England this year? The poll will close at 11:59 p.m. March 31st and I will post the entries. (Please include specific dates and exact numbers of each outlook to be entered into the contest) Last year, the SEE TEXT outlook is equivalent to the MRGL outlook going forward. This poll considers only Day 1 outlooks and not outlooks from days 2-8, as they could be eliminated prior to a potential non-event. 2014 stats: Date of first SEE TEXT outlook - May 10th 1630z (SW New England) 16 SEE TEXT outlooks (not including days that had prior or subsequent SLGT)Date of first SLGT outlook - May 27th 1300z (W New England) 17 total SLGT outlooksNo MDT risk outlooks - Last was September 8th, 2012 (Much of New England) The winner will simply have the least error points. There will be one error point for each day off and number of outlooks off. I'm still working out some thoughts for a potential tiebreaker. Any ideas? I toyed with the MDT risk category, but that may not help. Maybe total number of tornadoes in New England in 2015?
  11. Models are getting to be pretty insistent on an Apps runner happening the first week of March, the 00z GFS just levels the western 2/3rd of Tennessee with heavy snow and really buries Nashville. This has been showing up quite a few runs in a row now on both the GFS and GEM. The GEM looks like it has an icy solution on it's current run. GFS snowfall on top. GEM precip/radar on bottom.
  12. Hey everyone! I know this is a long time away, and we have plenty of time to watch it, but I think we all agree, there is going to be some kind of storm, even if its just a rain filled soaker. Any who, I have been getting a lot of questions about what is the wedge from my viewers so I threw that in there as well. Feedback is great. I don't care if its good or bad. IF you want to like my Facebook page and or twitter page that would rock as well, but you don't need too. IF you do, thank you very much. I am trying to expand those pages and get more interaction with y'all. Please share the video and invite your friends to like the page as well. Anyway, here ya go...Hope you enjoy! https://www.facebook.com/pages/Wxmanchris/690966551001476?ref=hl
  13. Discuss here because the severe thread is long and we are within day 3 range at this point. SREF is spitting out some impressive numbers already
  14. Individual storm/month/season threads for the entertaining 2013-14 cold/winter season. Storm Threads October 20-26, 2013 Lake Effect and Clippers http://www.americanwx.com/bb/index.php/topic/41455-early-season-lake-effect-and-clippers/ November 11-12, 2013 Cold Front/Lake Effect Snow-Rain http://www.americanwx.com/bb/index.php/topic/41649-november-11-12-cold-frontlake-effect-rainsnow/ November 16-18, 2013 Storm General Discussion http://www.americanwx.com/bb/index.php/topic/41691-november-16th-18th-storm-general-discussionobs/ November 17, 2013 Major Severe Weather Outbreak - Main Forum http://www.americanwx.com/bb/index.php/topic/41679-major-severe-weather-outbreak-november-17/ November 17, 2013 Tornadoes - A Fall Outbreak For The Ages http://www.americanwx.com/bb/index.php/topic/41779-november-17-2013-tornadoes-a-fall-outbreak-for-the-ages/ November 26-27, 2013 Snow Event http://www.americanwx.com/bb/index.php/topic/41783-november-26-27-2013-snow-event/ December 2-5, 2013 Winter Storm http://www.americanwx.com/bb/index.php/topic/41854-december-2-5th-winter-storm/ December 5-6, 2013 Winter Storm http://www.americanwx.com/bb/index.php/topic/41835-december-5-6-2013-winter-storm/ December 8-9, 2013 Winter Storm http://www.americanwx.com/bb/index.php/topic/41870-december-8-9th-winter-storm/ December 10-12, 2013 Clippers http://www.americanwx.com/bb/index.php/topic/41922-december-10-12th-clippers/ December 13-14, 2013 Winter Storm - Part I http://www.americanwx.com/bb/index.php/topic/41926-december-13-14th-winter-storm/ December 13-14, 2013 Winter Storm - Part II http://www.americanwx.com/bb/index.php/topic/41999-december-13-14th-winter-storm-part-2/ December 16-17, 2013 GL Clipper http://www.americanwx.com/bb/index.php/topic/42008-december-16th-17th-gl-clipper/ December 19-20, 2013 Winter Storm http://www.americanwx.com/bb/index.php/topic/42019-december-19-20th-winter-storm/ December 21-23, 2013 Winter Storm - Part I http://www.americanwx.com/bb/index.php/topic/42001-pre-christmas-winter-storm-potential/ December 21-23, 2013 Winter Storm - Part II http://www.americanwx.com/bb/index.php/topic/42040-december-21-22nd-winter-storm-part-2/ December 21-23, 2013 Winter Storm - Part III http://www.americanwx.com/bb/index.php/topic/42059-december-21-22nd-winter-storm-part-3/ December 21-23, 2013 Winter Storm - Part IV http://www.americanwx.com/bb/index.php/topic/42081-december-21-23rd-winter-storm-part-4/ December 21-22, 2013 Heavy Rain/Flooding/Severe http://www.americanwx.com/bb/index.php/topic/42061-december-21-22-heavy-rainfloodingsevere-threat/ December 24-30, 2013 Clippers http://www.americanwx.com/bb/index.php/topic/42083-december-24-30th-clippers/ December 31-January 2, 2014 Hybrid Frisbee Storm - Part I http://www.americanwx.com/bb/index.php/topic/42169-hybrid-frisbee-storm-december-31-january-2/ December 31-January 2, 2014 Hybrid Frisbee Storm - Part II http://www.americanwx.com/bb/index.php/topic/42213-december-31-january-2-hybrid-frisbee-storm-part-2/ December 31-January 2, 2014 Hybrid Frisbee Storm - Part III http://www.americanwx.com/bb/index.php/topic/42243-december-31-january-2-hybrid-frisbee-storm-part-3/ January 4-6, 2014 Winter Storm - Part I http://www.americanwx.com/bb/index.php/topic/42202-january-3-6th-winter-storm/ January 4-6, 2014 Winter Storm - Part II http://www.americanwx.com/bb/index.php/topic/42264-january-3-6th-winter-storm-part-2/ January 4-6, 2014 Winter Storm - Part III http://www.americanwx.com/bb/index.php/topic/42280-january-4-6th-winter-storm-part-3/ January 4-6, 2014 Winter Storm - Part IV http://www.americanwx.com/bb/index.php/topic/42296-january-4th-6th-major-winter-storm-part-4/ Early January 2014 Major/Potential Cold http://www.americanwx.com/bb/index.php/topic/42178-early-january-majorpotential-record-cold/ January 8-10, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/42261-january-8-10-storm-potential/ January 10-12, 2014 Snow/Sleet/Freezing Rain Winter Storm http://www.americanwx.com/bb/index.php/topic/42314-jan-10-12th-snowsleetfreezing-rainrain-event/ January 13-21, 2014 Clippers http://www.americanwx.com/bb/index.php/topic/42362-january-13-21st-clippershybrids/ January 20-?, 2014 Cold Snap http://www.americanwx.com/bb/index.php/topic/42450-january-20-cold-snap/ January 22-27, 2014 Clippers http://www.americanwx.com/bb/index.php/topic/42486-january-22-27th-clippershybrids/ January 30-February 2, 2014 Wave Train - Part I http://www.americanwx.com/bb/index.php/topic/42577-january-30-february-2nd-wave-train/ January 30-February 2, 2014 Wave Train - Part II http://www.americanwx.com/bb/index.php/topic/42650-january-30-february-3rd-wave-train-part-2/ February 4-5, 2014 Winter Storm - Part I http://www.americanwx.com/bb/index.php/topic/42599-february-4-5th-winter-storm/ February 4-5, 2014 Winter Storm - Part II http://www.americanwx.com/bb/index.php/topic/42680-february-4-5th-winter-storm-part-2/ February 4-5, 2014 Winter Storm - Part III http://www.americanwx.com/bb/index.php/topic/42719-february-4-5th-winter-storm-part-3/ February 8-10, 2014 Snow Event http://www.americanwx.com/bb/index.php/topic/42657-february-8-10-snow-event/ February 11-19, 2014 Clippers/Hybrids http://www.americanwx.com/bb/index.php/topic/42765-february-11-19th-clippershybrids/ February 20, 2014 Severe Weather http://www.americanwx.com/bb/index.php/topic/42919-february-20-severe-weather-threat/ February 20-22, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/42902-february-20-22-winter-weather-threat/ February 20-21, 2014 Heavy Rain/Flooding/Wind Event http://www.americanwx.com/bb/index.php/topic/42868-february-20-21-heavy-rainfloodinghigh-wind-threat/ February 22-27, 2014 Clippers/Hybrids http://www.americanwx.com/bb/index.php/topic/42984-february-22-27th-clippershybrids/ February 28-March 3, 2014 Winter Storm - Part I http://www.americanwx.com/bb/index.php/topic/43013-february-28-march-3rd-winter-storm/ February 28-March 3, 2014 Winter Storm - Part II http://www.americanwx.com/bb/index.php/topic/43071-february-28-march-3rd-winter-storm-part-2/ March 4-10, 2014 Clippers/Hybrids http://www.americanwx.com/bb/index.php/topic/43075-march-4-10th-clippershybrids/ March 11-12, 2014 Winter Storm - Part I http://www.americanwx.com/bb/index.php/topic/43126-march-11-12th-winter-storm/ March 11-12, 2014 Winter Storm - Part II http://www.americanwx.com/bb/index.php/topic/43176-march-11-12th-winter-storm-part-2/ March 15-17, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43175-march-15-17-winter-storm/ March 18-19, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43193-march-18-19-potential-winter-storm/ March 20-22, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43227-march-20-22-winter-storm/ March 24-25, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43278-this-clipper-ends-it-324-325/ March 28-29, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43309-march-28-29-snow-potential/ April 3-4, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43376-major-winter-storm-to-impact-mnwi-april-3rd-and-4th/ April 13-15, 2014 Winter Storm http://www.americanwx.com/bb/index.php/topic/43422-april-13-15-snow-threat/ Monthly/season threads Winter 2013-14 Discussion http://www.americanwx.com/bb/index.php/topic/40808-winter-2013-14-discussion/[/url] Winter 2013-14 Medium/Long Range Discussion - Part I http://www.americanwx.com/bb/index.php/topic/41492-winter-13-14-medlong-range-discussion/[/url] Winter 2013-14 Medium/Long Range Discussion - Part II http://www.americanwx.com/bb/index.php/topic/42324-winter-13-14-medlong-range-discussion-part-2/[/url] Winter 2013-14 Medium/Long Range Discussion - Part III http://www.americanwx.com/bb/index.php/topic/42943-winter-13-14-medlong-range-discussion-part-3/[/url] October 2013 General Discussion http://www.americanwx.com/bb/index.php/topic/41259-october-2013-general-discussion/[/url] November 2013 General Discussion http://www.americanwx.com/bb/index.php/topic/41522-november-2013-general-discussion/[/url] December 2013 General Discussion http://www.americanwx.com/bb/index.php/topic/41807-december-2013-general-discussion/[/url] January 2014 General Discussion http://www.americanwx.com/bb/index.php/topic/42122-january-2014-general-discussion/ February 2014 General Discussion http://www.americanwx.com/bb/index.php/topic/42604-february-2014-general-discussion/ March 2014 General Discussion http://www.americanwx.com/bb/index.php/topic/43006-march-2014-general-discussion/ April 2014 General Discussion http://www.americanwx.com/bb/index.php/topic/43341-april-2014-general-discussion/
  15. Pretty early to be in a Day 5 outlooked area for severe. Discuss upcoming threats, potential season impacting factors and more in this thread.
  16. EML's -- packets of desert air that originate in the inter-mountain west -- are often invoked to explain severe weather as far away from the Rockies as New England. For several months I have been puzzling how such dry (heavy, dense) air could maintain its coherence and altitude while passing the two thousand miles from ABQ to BDL. To put the question in the least technical way possible: Why wouldn't it fall down? Looking at SKEW-T's I see that such parcels of air are fairly common in the East, manifesting themselves as a sharp rightward movement of the temperature line, and a very sharp, leftward movement of the dewpoint line at some point above the surface, with the two lines reconverging at higher altitudes to form a sort of tent-like pattern. Over the last year, many intelligent and experienced people have contributed to this thread, and I am enormously grateful to them. Their work is a great resource for anybody curious about layering in the atmosphere and its relation to severe weather. This post has been promoted to an article
  17. Obviously two different events, but the first doesn't look like it will be much to talk about...thus a combined thread. Wednesday looks to have the most potential at this point. Unfortunately for chasers, this might be the last "ok" potential to chase for a while given the upcoming pattern.
  18. Virtual Storm Chase

    There is a great competition called Virtual Storm Chase that has been given new life (for bragging rights only). This is the same competition that was started over on the old wxchat forums several years ago (mid 2000s). For those that do not know what it is, I have a attached a PDF copy of the rules below. It is a great learning experience for those interested in severe weather forecasting and a great way for even meteorologists to keep sharp. http://virtualstormchase.info The site "appears" to be broke ... but once you register (free) and login it works. Rules: Rules _ VirtualStormChase.pdf
  19. Not much has changed. It is starting to look as if the warm sector will continue East in active form. Could see a multi day severe weather outbreak from the Plains to the Ohio Valley/dixie alley. People in KS, OK, MO, and AR really need to be paying attention to this. Original blog post on this: http://www.americanwx.com/bb/index.php/blog/8/entry-95-early-week-plains-severe-threat/
  20. Early Week Plains Severe Threat

    Looks to be a significant severe weather threat early next week. An area of low pressure is expected to develop and move off the Rockies … as usual with upper level energy approaching/crossing the Rockies. Ahead of this system, there will be an extended period of northward return flow off the Gulf of Mexico … setting the stage for a moist and unstable boundary layer as our system moves in around Monday. A dry line will develop across Western parts of Kansas, Oklahoma, and Texas. As the dryline moves East, forcing (dryline and upper trough) looks to become sufficient for the development of thunderstorms within moderate to large instability and long/open hodographs. If things hold, would likely be a moderate or high risk day from SPC … with violent/strong long track tornadoes possible across parts of Oklahoma and Kansas.
  21. While still being a day 5ish event, it is not to early to start looking at some of the possible implications of various models. At this juncture, we generally have the GFS and the Euro book-ending a possibilities window that includes a cutter to Chicago and a more suppressed system that goes East of Hatteras For the most part been consistently left of the GFS ... with its ensembles a tad to the right of the operational Euro (but no where near the GFS). The 12z GFS Ensembles cut the difference with somewhat of a middle ground ... bringing the primary low into Ohio, with a coastal transfer. Depending on the amount of moisture return that is achieved in the warm sector, the operational GFS could be a notable severe weather event. And would keep QPF amounts across the DC/NOVA area on the light side with little possibilities for winter weather. The transfer with this solution simply happens too late to provide the lift for precipitation and wraparound of cold air. Then we have the Euro with it's more southern solution. It would mean a smaller spatial window for severe weather possibilities and a better chance for wintry weather for the area (especially west ... like we saw with the early March event). Given the time range and the placement of the the ensembles in the middle of the operationals I would expect to see some compromise towards the middle in terms of track over the next 1-3 days ... rather than an extreme on either side verifying. If I had to pick a solution verbatim from this mornings 12z suite for the heck of it, it would be the GEFS.
  22. I have been following Lezak's Recurring Cycle (LRC) since last winter when I first heard of it. After the Midwest blizzard on December 19-21 came ~51 days after Superstorm Sandy, myself (and many others in the field) recognized this as the cycle length for this winter. I have spent the past month telling all my co-workers we would have another blizzard on or around February 9 and here we are. For anyone who is not aware of the LRC, it is a cycle that begins when longwave trough/ridge patterns develop at the onset of the cold season. The cycle is typically 40-60 days and is usually different each year. Once the cycle length is established, it typically remains the same for the rest of the season. While there has been no peer-reviewed publication (that I am aware of) on this topic, it is being recognized more and more in the meteorology field. Today I chose to examine the cycle even more closely. First, I believe there is a lost first leg of the cycle which began with the severe weather outbreak on September 7-8 as well which has not been talked about much in most blogs/forums I have read on the topic. Second, an interesting point that I hope to point out is that each initial system this year was followed by semi-big storm 7-10 days after the first. This seems like it will likely occur again with both the GFS and ECMWF indicating another big storm system on the east coast next weekend. Here are some maps to support this theory. September 7-8, 2012 - Manhattan Tornado 51 days later October 29-31, 2012 - Sandy 51 days later December 19-20, 2012 - Midwest Blizzard 51 days later February 8-9, 2013 ____________________________________________________________________________________________ 10 days after September event September 18, 2012 - East Coast Severe Weather 9 days after Sandy November 7-8, 2012 - East Coast Nor'Easter 7 days after Midwest Blizzard December 26-27, 2013 - East Coast Nor'Easter 8 days from now??? February 17-18, 2013 Over the next week we will have to see how this plays out. I am interested to hear if anyone else has followed this cycle and has anything to add. In the mean time, I am throwing it out a prediction for a severe weather/tornado outbreak 51 days from now between March 31 and April 2 across the southern states. April Fools Day outbreak anyone?