nrgjeff

Cheeseland is passionate about severe wx and welcome here. Note the smiley face. I was going to take down my Christmas tree MLK Day weekend. If it is still up Monday, I will also use the shutdown reasoning as a later deadline. Wetumka tornado is an unfortunate verification of the 5%. These things can happen with a dynamically forced line marginal instability. Most importantly sky will clear out in time for the lunar eclipse tonight! High clouds could come into the northwest quad of our Region but not a show stopper.

Saturday showcase includes thunderstorms. CAMs mostly line out the activity which is not a surprise. Line will be very forced with limited instability. Kinematics and wind field looks excellent. Rain and clouds should keep it a little cool though. If instability somehow verifies higher it might be worth a second look on a weekend. Otherwise the real show is the ESPN Saturday Showcase; lots and lots of good college basketball. Sunday evening should clear out in time for the lunar eclipse. Yes, back to fair weather chasing.

NAM raised snow amounts like it is playing catch up to the Euro. NAM still relatively lower amounts might be due to surface and ground temps. However right after Thanksgiving the Euro scored a big coup even inside the time frame where the NAM should prevail. Might have happened one other time, but I remember Thanksgiving more thanks to visiting KCMO. Looks like a big I-70 special from KC to STL. Everyone enjoy! And the Chiefs better win!! PS. Climate blog looks solid. More TV Mets should do that.

ECMWF and CFS monthlies both show April better than May. Fits El Nino climo. So I will look early and often in Dixie. Plains may be yet another crap May. No EML in the Plains means slop. If I'm going to chase slop, Dixie is a whole lot closer!

Bye bye severe wx season.

I remain bullish, slightly cold, for winter. Current El Nino is moderate, but it's only a snapshot. Two of the last three weak/mdt El Ninos briefly spiked strong before trailing off. Those were 2002-03 and 2009-10 both cold winters. Most recent weak-mdt El Nino 2014-15 stayed below moderate; it was also a cold winter. November verified cold eastern half to 2/3 of USA. It looks similar to 2014, but that year was colder to the East Coast. This year remember the cutter systems? Snow fans of course want that to end. Anyway 2014-15 was the last snow thump in Chattanooga. I'm quite comfortable with ENSO at the moment.

Saturday afternoon events Middle Tennessee and points west might luck out if rain can get out before events start. John I hope the Christmas parade works out. I've lost interest in thunderstorms; so, I will hope for fair weather. Appears severe starts Friday in the Ozarks; even more LOL with early sunset. Saturday dynamics seem to drift north of instability; so, rain here should be fairly benign. Rain timing should be in the morning many areas, including Mid-Tenn. Might still be afternoon showers in East Tenn. GFS is slower (wetter for Mid-Tenn) but ECMWF and NAM both push out the rain in time.

ECMWF remains consistent with a chance of severe weather Friday night and Saturday from the Mid-South to the eastern Tennessee Valley. Many details need to work out from instability to short-wave timing. Looks like multiple waves, which can giveth or taketh away. I infer from the text SPC really wants to outlook Saturday, but I agree it would be hard to place the 15%. Too early to worry for those who dislike severe. Just those of us who like it, we want to track it. Honestly, at Day 6, it is not any more likely than snow in Dixie, lol! PS.. I will comment on December after the ECMWF weeklies update. Maybe I should have stayed with Carver for Dec. Did I go cold too fast?

I was in KCMO for Thanksgiving and enjoyed tracking the storm. Interesting that at 30 hours the ECMWF just schooled the NAM. I joke about the latter choking 36-48 hours out, but it should beat the Euro and GFS inside 36 hours. NAM finally caught on farther south by 24 hours out. Euro was first to sniff out the vort max keeping south. NWS did a great job going Blizzard Warning. Plains pattern recognition promotes doing so with a tight vigorous vort max and deepening surface low press. Then, how about some thunder snow? Little busy with family to post or look deeply, but I was following it. For safety we departed Saturday evening before it started, so I missed the real fun. Wish the blizzard had been a day earlier.

European weeklies have a possible pattern the week after Thanksgiving week; so, a little later into the end of November.

I'll go with the ECMWF Euro as usual. Either way it is rainy crap weather on Election Day. Consider early voting if not already done, weighing the next two days also. Halloween is today and looks like rain tomorrow (Thursday) which is the last day of early voting. I respect no politics on the weather board; we love weather first. Just a note on weather related logistics. Happy and safe Halloween!

The increase in tornado activity on the Delta is convenient because it is flat. However that is just change (delta on the Delta, lol). The Delta is still a local min within Dixie Alley. Maybe it will change.

Confidence is greater on El Nino after data the last couple weeks. I've been around but quite busy at work and home with activities. Also American Wx fell off my routine when it crashed for a few days. El Nino could still turn out basin wide, but odds slightly favor Modoki.

CFS is also on fire all winter. Both models may be influenced by generally warm oceans over the entire Northern Hemisphere. Perhaps the late bloom of El Nino will behave more like weak Nino; and, get us some winter back half per ECMWF.

Too bad the TNI may be completely backwards for severe next spring.

Looking back through the 2000s when the surface and below-surface cross-sections look like now, odds are pretty good for the weak/moderate El Nino. Right on the cusp of the two would be great! (Office Space meme) Few folks are haunted by the ghosts of last year. This year is quite different. LY had started to crater by August. Consensus in the energy world is weak/mdt El Nino. It might fade mid-winter but does not break the deal. They are supposed to peak in late fall early winter; hence, the name. Literally it is the Christmas Child, El Nino in Spanish.

Starting Monday it looks cooler again, perhaps for most of next week with scattered thundershowers. Tuesday is currently the day models/NWP highlights for heavier storms in the Valley, but it has shifted around. 36 hours ago NWP favored Monday. At any rate a synoptic system with quality upper level wind fields is forecast early next week for the Valley. Looks mainly eastern half of our region perhaps Tuesday. GFS has upper level wind speed but mostly same direction. Euro has more turning upstairs, upper system a bit more open. If it rains the day before, chance of an outflow boundary increases. If timing changes it could be Mid Atlantic (per NWP 36 hours ago). Finally we'll see if the wind field forecast holds up. Most days with thundershowers should not be severe. Over five days we should be able to absorb that QPF without major flooding concern, at least in Tenn. However the devil is in the local details. Local flash flooding is always possible with thunderstorms. Also with sustained southeast flow, Georgia and up the Blue Ridge could have a lot more precip.

Friday night set up east of the highest SPC probabilities. Believe the main problem was a warmer layer (cap) for Middle Tenn. Meanwhile a boundary set up from Kentucky to North Georgia. It started out in Middle Tenn. but was capped. Despite lower overall parameters east, the low levels closed the deal. Boundary enhanced low level shear. It got real near Spring City for a bit. Neighbors and I were watching the distant lightning. Watching the lightning reminded me of waiting for nocturnal storms back in the Plains. However we were concerned for the people up in the tornado warning.

I am sitting out today, mainly due to terrain. Iowa tornadoes did pique my interest but they had greater low level turning. Iowa tornadoes is all or nothing like snow in Dixie, lol.. Today in TN/KY deep layer shear is downright robust for July. CAPE should achieve advertised levels. My issue is the lowest level shear. Even adjusted for a northwest flow event I don't like the lowest 100 mb or so. From 850 mb up turning is good. However from 850 mb down speed is meh. I know it's July. Still I like the lowest levels to close the deal for tornadoes. It requires a quality boundary. Attm (1643Z surface chart) winds do not kink well along the boundary near the TN/KY border. We'll see how things go. Looks like plenty of straight line wind and even large hail for severe weather fans. OHX is rightfully hitting the straight winds in their comm. Can't take tornadoes off the table in the MDT and immediate surrounding ENH area (not all of it). Note max tornado probabilities are ENH. The other modes of severe wx could achieve MDT. If the terrain were better, today might be worth a try in West Kentucky and adjacent parts of Tenn. The meteorology looks like few and brief tornadoes, easily missed in poor terrain. Appears the wind and hail will be the primary issues.

Expanding the ENH and introducing hatched hail both seem reasonable. OHX afternoon discussion reads ever so slightly more interested in tornadoes; however, they are rightfully mainly focused on straight line winds. My previous post was after 12Z CAMs, so I have little to add there. Interesting the 850/925 mb winds appear a little better in northern Kentucky. However the stronger 500/200 mb winds are down over Tenn. Could we have more than one or two good cells and spread out? Gee that would be something unusual in 2018! I'm starting to actually think about this northwest flow event. Still doubt I'll chase due to awful terrain. I mean in 2018 something has to go wrong.

I do like it! Storm mode remains a question for me. About 1/3 CAMs still produce a line in the late afternoon. Most have one in the morning, which is fine if it lays down outflow. My question is the afternoon round. ARW (research version of WRF) just put out a junk scenario and I hope it is an outlier. At any rate the chance of afternoon storms quickly going into a squall line is real. All the shear and turning with height could just translate into a well-maintained straight line wind producing squall line. THEE checklist probably won't be met, not quite enough WAA. However a shortwave in northwest flow with lots of heat humidity and CAPE could get some damaging winds going. NAM version of the WRF mostly favors supercells. 06Z was a little messy but 00/12Z are supercells in the afternoon. I am still skeptical of the lowest levels 0-1km. Now the 0-3km SRH is robust for July (but average spring system). The 0-1km needs something more. How about a boundary? Morning convection would need to produce that just-right outflow boundary. Can't have a cool pool undercutting, a risk without vigorous inflow. If rain gets off the said boundary, it can cook for a few hours in the afternoon. NAM has a hard right mover on the boundary in Middle Tenn. I would not take that location seriously at 36 hours. Only the conceptual model is worth noting. If a lone supercell establishes on a cooking boundary (no other rain) then the large hail scenario gets more likely, perhaps even rotation. For the latter, I think a little more ambient 0-1km SRH is needed even if a boundary is present. Due to forecast overnight and morning convection the location is actually still up in the air. I like the Slight-Enhanced for Kentucky and Tenn. Ohio Valley also has a triple point forecast but that is another regional forum area.

Wow that's some bullish language from OHX. Keep in mind it is an internal discussion; and, they should go over all the possible solutions. Other solutions include the classic Dixie crap out scud nation. Getting serious, I like a slight risk for part of the region. Wind fields certainly support it. I believe the high-res NAM is too amped with SRH. Might be locally higher on a boundary; but, the other NAM is less bullish overall. Either way CAPE will be high and storms will tap into those wind fields. While maybe not enough turning for tornadoes*, it is enough veering with height to promote organized severe storms. * Hard right mover on a boundary could still surprise. Yeah maybe look on the Plateau. I believe low level wind fields (its ground level) are stronger up there for two reasons.. higher elevation, and broad Bernoulli effect as mesoscale winds flow over the Plateau. Friday could offer a nice break from the Good Morning Vietnam forecast. Like the June 20-ish week we should start a few days with organized thunderstorms. Slight could also shift toward the Mid-South if the boundary sinks.

Impressive video @*Flash* from June 26. Takes me back to the Plains with a disco strobe anvil topped thunderhead. Hopefully we can do it in the Valley (and Midsouth) later this week and over the weekend. Modest flow is still forecast over that period, I'll say Friday through Monday. Turning with height is meager but the speed is pretty good for this time of year. SPC does not sound too impressed, but at least we get the marginal text mention. Should be enough for organized storms, vs just pop-up poop-out. All I'm asking for is a little straight wind, good shelfies, and lightning shows. You know, this summer still feels a little empty without the 2017 eclipse anticipation.

June 28 evening was my lightning show of record for 2018. In fact it's the best I have seen here in several years. We had frequent lighting for nearly an hour with nearly constant rumbling of thunder. On two occasions continuous lighting went for a few minutes. Separately, a few booms of thunder shock the house. Being at night of course helped with the light show. We had stronger storms a few days before that. June 28 was more about the lighting and thunder. Hopefully modest flow aloft in a few days will bring more fun. Real storms please!

Friday and Saturday should offer at least something to watch. I would put it in the category of the June 21-28 weather with modest upper level flow and some severe wx reports. ECMWF continues to show greater than seasonable upper level flow. It veers with height, but the low levels are far from backed to start. Looks like a straight line wind pattern. A hard right mover on a boundary (SSE motion) could spit out hail too. 06Z GFS trends toward the ECMWF with a more open wave, as opposed to broad but closed off, which creates a little more veering with height on the GFS. Wind direction at low levels does not favor rotation. However veering with height upstairs still supports the chance of severe wx mainly in the form of straight winds. We'll see if it holds.