nrgjeff

My best guess is April could be a short but intense window for severe. March could be tempered if this SSW causes delayed effect blocking and cooler than normal temps. If the ECWMF is right March could be stormy, but it might be too warm. While I'm fading the SSW hype, I also think the Euro is too warm. April we should still have the La Nina signature which is correlated to severe. If it fades then May might calm down faster than usual in Dixie. Note overall May will still be the national peak. If the Euro is right March will get going quickly; otherwise, looks like we just have to get through April.

Twitter thread might be better news for Heartland snow lovers than me over in Tenn. Wavelength may be shorter than the January attempts (me). See his whole Twitter thread about cold in general..

Kelvin wave may save the first half of severe season. Dixie is due for a whippin'.

Yes sir. Let us keep jawboning and maybe we can will a good severe season. We can do without human impacts. Just give us stuff to chase!

Latest Kelvin wave should lock La Nina for a few more weeks at least. Dixie Alley should have an active season. We go earlier than the Plains, so it is indeed time to make the call. MJO is creating massive heat flux into the Mid Latitudes. SSW may not matter. Peer reviewed research shows a weak correlation for North America; better for Eurasia. So, I will go with the warm ECMWF weeklies. Weeks 5-6 introduce a West trough with southwest flow over Dixie. That'll light it up!

Normally La Nina is bullish the entire severe weather season from Dixie early to Plains late. However this year features trouble from a southern Plains drought and possible transition toward El Nino. CFS keeps La Nina but it is horrible predicting spring/summer during winter. More likely Nina fades which makes severe wx fade. Drought would indeed favor east of I-35 in the jungle. Still May is by far the climo peak out there. Last year we posted some papers about all four phases (Nina, Nino, and TNI both directions). After years of skepticism, research is revealing some correlations.

Just need it to hold on until May for my Plains trip. If the Euro weeklies are right about weeks 5-6, action should get rolling in Dixie in March. CFS would keep things quiet longer. With La Nina still going in March I have to learn toward the Euro here.

We might be able to make 2018 even more boring than 2017.

The Lezak and Heady cycles have a period similar to that of the MJO. Some years are great and some are tough. Majority work out. They combine all methods - including their own - for seasonal outlooks. I believe it's solid. Well all need a beauty from the central/southern Plains and Ozarks through the Tennessee Valley.

We'll probably get slammed once or twice. SER should become more of a fixture into March, regardless of NWP. However the subsurface is a disaster for Plains chasing.

Day 1 severe could be an ugly preview of all season east of I-35. Fading Nina and drought in Texas spells crap storm chasing. Still I hope one good week out there. Hope it snows in Feb. Super Nino torch next winter! unless the sun...

Need La Nina to hold on into May for Plains peak. Last year that crap out was a total disaster for chasing. Of course it was not a total disaster for civilians.

Well 2011 was a weak La Nina with snow in January and a warmer February. In no way would I ever joke about those tragic events. However I'm expecting an active severe wx season.

We are safe from severe for a while. However I love getting the thread going early and often! La Nina should get the South/Dixie going early and often as well. Plains would peter out if a quick transition to El Nino. It is all relative though. In the Plains even a BN severe May has opportunity. Last year is a good example. If one is flexible, I figure a good week will show up in May out in the Plains. I'm counting on it! Back here, looks quiet balance of January. We have cold snaps scheduled this weekend into early next week, and again at the end of the month and first of February if one believes the Weeklies. I figure the warmer middle and end of February (monthly forecast) would get severe going a little bit.

First, congratulations to all who enjoyed a rare big snow at the coast! Math, plus chemistry and physics if they offer it. Even something like Economics helps with the thought process of modeling a complex real world. CAD stands for cold air damming. It is when low level cold air banks up on the east side of the Appalachians. Look for surface high pressure to the northeast keeping a northeast or north wind fetch into the Carolinas. WAA aloft should not dislodge surface cold in that situation, but the surface high must keep pushing in cold air for winter precip. Retreating high press allows WAA at the surface and just regular rain. High resolution models are best, but all models still struggle with it. Finally CAD also occurs along other mountain ranges. The Rockies are notorious for the Plains. However it's normally snow not ice in the High Plains. There the challenge is how much to undercut MOS. Pacific Northwest can have nasty ice events when cold air drains down the Columbia River basin. It is not really CAD west of the mountains, but same principle.

Nashville NWS turned markedly more optimistic this package as 12Z guidance really dried out the column and PWs. Morristown got bullish this morning, issuing a forecast that is better than Nebraska climo. It is forecast time! Nashville and all of the Tennessee track should stay on the list of possibilities. We may get a lucky break with weak surface ridging and slightly rising 500 mb heights. Kentucky enjoys similar improvements to a point. None of this is a guarantee, but he region should stay on the short list.

KCMO area back through Nebraska has MCS risk, and it is too early to tell what time of day. However climo is night/morning. A lucky scenario would be subsidence behind any early MCS suppresses Cu. Then the partial phases keep Cu in check. Risk is lingering mid-level clouds. East Tennessee might edge out Nashville for a couple reasons. Lower elevations in the Tennessee Valley usually have slightly less Cu. Current NWP has a stationary front encroaching from the south, which must also be watched. North side of Totality in the Tennessee Valley (valley lower el.) is also farther from the said front (models verbatim). STL Carbondale Hopkinsville are kind of a crap shoot right now, anything from MCS hell to weak (but favorable) surface ridging. South Carolina depends on a boundary. Data and cell coverage will be awful to non-existent in Totality. We lose data on obvious dry line stakeouts. Everybody already knows the path of totality. So, I would not make target decisions based on cell networks. Forecast it right in the morning and use visuals for repositioning if needed. One could also call someone from a land-line for a nowcast.

Most of the eclipse sites, including Great American Eclipse, Eclipse2017.org and NASA, recommend not fumbling around with cameras and equipment. Even with practice 'dry runs' the total eclipse time is too short and precious. Still risk missing it. Plus professionals and media will get pictures. Finally, we will remember it better just watching from the corona to the sunset/rise on all of the horizons. From personal experience I remember best events I did not photograph. Saw a nearly overhead Aurora (northern lights) in Jasper, Canada 25 years ago and I still remember it like last night. Couple brief tornadoes I failed to photograph are the ones I remember best in my mind. So, my only equipment will be ISO/CE eclipse glasses and a shadowbox/pinhole viewer.

Like to base out of Winnipeg for Friday, but I will have to do so vicariously. Keep in mind Manitoba is excellent chase terrain both south and west of Winnipeg. One can even go east or north slightly without running into the forest or lakes. Friday issue could be MCS favored over discrete but we'll see. Saturday could be a break between waves before the Northwest trough settles in more Sunday. Then looks like pieces of energy eject Sunday and Monday, with the main trough Tuesday. Biggest problem I see is surface low and boundaries under the cap. ND is not capped but it is cool sector. Low and boundaries appear in SD. Still a few days for those details to iron out though. One bearish shift for chasers is the ensemble members are falling into line with operational models. Previously 30-40% of members were better than the ops. They were deeper with the trough, but no more. Odds of cap issues are up. One might be forced to chase the WF which requires a delicate balance between the cool sector and the cap. Tuesday the WF and quasi-DL could both go. However we know how main trough ejections have panned out the last couple years. Need to avoid the slop and/or going into the Minnesota trees. This is a good sequence for northern Plains chasers, but I'm not sure it is a travel set-up.

Euro is smokin' the GFS. Note the lead-in to Saturday. While the GFS and even NAM tried to get the LLJ going, though veered, Euro never really did so. Comparisons to 5/6/03 or 5/10/08 became invalid by morning as one realized no LLJ. While the GFS and 84hr NAM now want to get the late week going, beware of the Euro veto. Story is similar next week. GFS is bullish. Euro is skeptical. However Euro is at least introducing modest flow over the Plains. Second week of June may perk up also. I know that is a delay from the first week of June. However it is not unusual for crap patterns to go a little longer than forecast. If the CFS and Euro weeklies are right, the pattern could become more bullish second week of June.

State of the Chase Season still looks good. Synoptic season may be winding down, but quality set-ups will continue as we roll through the peak weeks of tornado climo. Later this week features modest WSW flow over a high CAPE environment. LLJ responds to upper waves a few days. Should be a sharp dry line and other boundaries. Details have yet to work out regarding the cap Thursday and LLJ over the weekend. Expect 1-3 good chase days. Late next week once again a trough may dig into the Rockies. Ensembles vary on timing but a majority have it dropping in there. Favorable pattern may be present into the week of June 5 as well. MJO and tropical Pacific are friendly to these weeks. Perhaps a couple good chase days both weeks of May 29 and June 5. Each week could also feature a sleeper day. Even if just normal activity, we have a friend in climo.

You are on the right track. Keep it simple weeks 3-4. Actually keep it simple week 2 also. GFS/Euro go out through week 2 but you've seen us make fun of the 11-15 day. Looks for a nice trough and the right pattern, not details. Weeks 3-4 are available on the CFS and Euro weeklies. That's an even quicker glance for the right pattern. First the GFS/Euro: I like a Rockies trough at 500/200 mb with SW/WSW flow over the Plains. SSW or S flow is not as favorable. If you are curious check 850 mb for a LLJ response S/SE there. It'll be there with a good trough, so maybe only check if a marginal trough. I prefer the downstream ridge over the Southeast, not the Upper Midwest, for several reasons including upper level winds and low level moisture. Just checking for wind direction with height and surface temps/dews. Weeks 3-4 are even simpler and quicker using the CFS/Euro weeklies. Most of the 500 mb presentations are height anomalies. While similar to the 500 mb heights chart, some cautions. What might look like a deep Southwest low could be a closed low, not ideal but can work. On the plus side, what looks like a meh northern Rockies trough could be favorable for subtle waves ejecting. The latter will start to look better on the GFS/Euro if the forecast holds. Finally I only use indices within a few days. Indices really just summarize the fundamentals. Turning with height and instability should yield good indices. Indices that incorporate directional shear should show local maximums along boundaries. Mismatches require looking back at the fundamentals. Another outflow better than the warm front? Any ongoing rain? Could be anything, but one has to figure the mismatch and adjust. If all lines up, a chase target is born.

Back half of of May is looking good for chasers who can forecast. Might be a couple big days, and maybe a big crap-out; otherwise, looks like a nice set-up picker's market. Closed lows (like this week) can and do produce like Wray Colorado. Week of the 15th, late that week near the Rozel anniversary, looks like a gorgeous open trough. Still fighting remnants of East trough, but the Plains can recover quickly in mid-May. Ensembles and weeklies hint at another trough week of May 22, again maybe later in the week. The later in May the better. Yes, it is hard to screw up late May barring a total debacle pattern.

If the current weather pattern holds, troughs Central and Southeast ridge, the Midwest fall/encore severe season could be at least somewhat interesting. PDO and ENSO analogs favor at least semi-persistence. Weeklies keep ridging East or Southeast with occasional troughs Central. Naturally Rockies troughs would be ideal for the Plains but most seem to be forming Central. Corn Belt can and occasionally does deliver in fall. I prefer September with the longer days but the above PDO/ENSO analogs have some trough west ridge east in October. My other reason for a September focus, is something other than the heat dragging on locally here in the Tennessee Valley. Living vicariously in the Midwest...

Welcome to the Forum and Central/West. Actually I find temperature forecasting quite interesting during the summer in California. One has to look at the marine layer from the coast into the valleys and the sea breeze later in the day. I find Southern California more forgiving. Some days a marine layer or sea-breeze forecast error can negate the other, saving a daily temperature forecast but the hourly may be a mess for a few hours. Northern California coastal valleys can be particularly unforgiving if one blows the marine layer and/or wind direction. Monsoon pattern also offers good forecast challenges. While temperatures do not make for good drama on a forecast forum, it is still interesting to follow. Otherwise, live vicariously in the Plains for some real weather action. Again welcome to the board and region.