Central/Western Medium-Long Range Discussion

[nrgjeff]

Ian you are golden. GFS stands for curse words. Euro and Canadian keep warm sector in tact for next weekend. Both their ensemble products maintain the North American pattern into the 11-15. Euro weeklies and CFS maintain into early June. I think you get all that data, but just a reminder everything but a crappy op model is on your side.

 

I'm reluctantly letting this weekend go based on long travel and odds. Tornadoes will verify today and tomorrow, but terrain issues are noted in NE/SD today. Tomorrow target is so diffuse I'm not betting a 700-800 mi drive on anywhere. However for those already out there, tomorrow will verify. Kansas sups may have issues with poor inflow and/or bad hodos. Eastern OK could go on the OFB with excellent shear but terrain could be an issue. Bust activity: Talimena Parkway is a gorgeous scenic drive.

 

Lead up to Memorial Day could end up wet too. However I know this weekend is a mess. There is still hope for next. Much of next week a broad West trough is in place ejecting occasional short-waves. Each time a 250 mb jet comes out the LLJ at 850/925 mb responds. If a main target rainout, upslope would probably verify. It will work out one way or another. Late May climo favors tornadoes.

 

Beyond that a recurving Pacific typhoon could have impacts. However Euro/Canadian ensembles do not echo GFS ens pattern change. Either the typhoon is not strong enough, or it just gets absorbed into a mid-latitude system within the already established buffet line of Pacific systems. Good to go!

[Ian]

Yeah, I think things still look more favorable than not. If I could go back and redo I'd probably not have shifted into June and done the usual last two weeks of May but not sure there will be a huge difference in the end. This coming week overall looks fairly favorable, main limiter may be how much moisture can get north following the weekend event. 

 

Dailies on the Euro weeklies that came out this morning on wxbell look overall good.. higher heights everywhere going forward eventually but no shutdown look or anything. 

 

Looks like we may leave a day early -- next Thur v next Fri -- to make sure we catch the next weekend trough in full assuming it happens... in case there's a break after. We've been spoiled in recent years having almost no down time.

[BlizzardWx]

Yeah, I think things still look more favorable than not. If I could go back and redo I'd probably not have shifted into June and done the usual last two weeks of May but not sure there will be a huge difference in the end. This coming week overall looks fairly favorable, main limiter may be how much moisture can get north following the weekend event. 

 

Dailies on the Euro weeklies that came out this morning on wxbell look overall good.. higher heights everywhere going forward eventually but no shutdown look or anything. 

 

Looks like we may leave a day early -- next Thur v next Fri -- to make sure we catch the next weekend trough in full assuming it happens... in case there's a break after. We've been spoiled in recent years having almost no down time.

The weeklies on wxbell come out Mon and Thurs for the record. Good luck with your chase though!

[Ian]

The weeklies on wxbell come out Mon and Thurs for the record. Good luck with your chase though!

ahh must be late? Know they hit SV in the afternoon or early evening but usually don't see them on wxbell that quick. At least the daily stamps of it.

[BlizzardWx]

ahh must be late? Know they hit SV in the afternoon or early evening but usually don't see them on wxbell that quick. At least the daily stamps of it.

Possible, I just know they were out for me yesterday so maybe you need to clear your cache or something.

[Quincy]

Euro weeklies should be out by 8pm eastern time M/Th on WxBell.

[andyhb]

Not sure about the Euro weeklies, but the monthly forecast from the CFSv2 for June looks pretty favorable currently. Strong northern stream on the 200 mb U-wind anomalies plowing into the Pacific NW with net troughing in the Gulf of Alaska, cool temp anomalies across the western/central CONUS and warm in the east.

[Ian]

Ensembles have been waving back and forth lately.. Not as steady with a good look as they were when May was starting at least. Should sort of expect shear to generally relax I suppose anyway but the last day or so of runs have been a little worrisome after this coming weekend. That said 20-30kts shear in a fairly zonal flow should have some little ripples I think. Euro also has another trough hitting the west coast around day 10 last two runs.

[Ian]

Op GFS has the next trough too now. Of course that'll prob change at 6z.

 

Gut says the pac jet keeps on coming but it has been a bit bouncier overall lately.. guess we'll see.

[andyhb]

Late May-June 2004 showing up a ton in the CPC 8-14 day analogs today.

 

[Ian]

Op models still waffling a bit but seems an extended period of SW/W flow is possible based on ensembles. Looks like a high CAPE regime tries to get established next week. Today's 12z definitely show some bigger potential intermixed too.

[andyhb]

June 1957 and June 1958 also had some bigger events in the N Plains and Upper Midwest (F5 in Fargo on 6/10/57 and F5 in Colfax, WI on 6/4/58).

[brettjrob]

Recent operational runs are a bit concerning heading into early-mid next week, but it's a period of low predictability per ensembles. I'd be fine with some downtime next week for a pattern "reset," hopefully featuring a period of drying for the Chihuahuan and Sonoran deserts and reduced STJ influence. Plus, so far this season since late March, a broadly favorable pattern has found a way to reassert itself quickly during every period of doubt.

 

With the amazing ET this year, all we need is one or two decent (even subtle) troughs the rest of the spring without the overwhelming STJ influence, and periods comparable to late-season 2004 or 2010 should be easily within reach. It will be a crying shame if the grungefest setups continue unabated through May and June, but still better than some recent years.

[andyhb]

With the amazing ET this year, all we need is one or two decent (even subtle) troughs the rest of the spring without the overwhelming STJ influence, and periods comparable to late-season 2004 or 2010 should be easily within reach. It will be a crying shame if the grungefest setups continue unabated through May and June, but still better than some recent years.

 

We still haven't had that bigger event/outbreak to accent the season yet. There will likely be moisture in spades, just a question on whether the Pacific cooperates. A northern shift will help with the EML situation, with more favorable 700 mb trajectories.

[Ian]

I'm mixed on the pattern. The jet channel stays more or less across the plains... Just quite weak on some runs. I dunno.. Seems like there should be little impulses riding along it at the least. We'll see I suppose. We're coming to visit you Brett if down days so hope for storms. ;p

[BlizzardWx]

Anybody have any general thoughts for west-central Texas (Abilene) for around June 3-9? I'll be there then and would love to see some fun stuff and possibly do some chasing if its close.

[andyhb]

-EPO block is going to be a problem through the next week at least, need that to break down/slide east a bit so the jet from the Aleutian low can advance east. Until then, might be more nickel and dime setups vs. bigger events.

[brettjrob]

-EPO block is going to be a problem through the next week at least, need that to break down/slide east a bit so the jet from the Aleutian low can advance east. Until then, might be more nickel and dime setups vs. bigger events.

 

Agreed -- we'll just have to see whether we can manage 35-40 kt of bulk shear over good instability to determine whether those nickel-and-dime events are fruitful. Really, almost every Plains event this entire spring so far has been nickel-and-dime in terms of results, though, despite so many promising longwave troughs. So results-wise, this may not be that much of a dropoff.

[Quincy]

The day 8-14 GEFS mean continues to look mildly interesting with at least modest western troughing. However, the new Euro weeklies are the kiss of death with a mega ridging building across the central US after June 6/7. I'm not sure how much stock I'll put into that projection, but something to watch in later ensemble runs.

[Quincy]

The 00z Euro depiction of a modest trough moving into the Pacific Northwest to start June is supported by the EC ensembles. It's a ways out there, but verbatim would feature at least some severe potential from the central/northern Plains into the Upper Midwest. Worth watching I'd say in an otherwise increasingly meh pattern to finish May and prospects of stronger central US ridging deeper into June.

[Thundersnow12]

My second trip leaves Friday and after a little break of model watching, I finally looked this morning..

 

The 0z Euro and 6z GFS have me cautiously optimistic for some good chances across the nrn plains beginning as early as Monday possibly but hopefully getting even better just after that. 

[brettjrob]

Been watching the period next week on the Euro for several runs, and I'm concerned that it's consistently depicted most of the upper flow north of the front. There should be at least a half-state area of 25+ kt H5 flow over the warm sector for several days, hopefully.

[jojo762]

On a side note, the 12Z GFS develops an odd weak cut-off low around 108hrs over Louisiana. 00Z ECMWF does a similar thing just a day later. Both models just have the feature sitting over LA/the Arklatex for a while seemingly, and don't do anything with it... Also both models are hinting at SW flow beginning in the plains/northern plains toward the end of next week.. Fairly weak trough, but still something..

[Msalgado]

GFS looking like we might have at least one more round of stuff next weekend here in Texas.  I have a research field campaign that will likely start the following week so I'm hoping this pans out for one last hurrah this season.

[andyhb]

What I seem to be seeing on the recent ensemble guidance is a tendency to shift high latitude ridging eastward over central Canada past the first week of June. Should this happen, it would likely open up an opportunity for the Aleutian low to slide east and allow a relatively open path for its associated jet to the West Coast (with an accordingly active pattern downstream).

[JoMo]

Signs of a summertime high showing up, eh? Yes please, we need to dry out.

[brettjrob]

If only that upper low progged to sit over CA late next week into the weekend were shifted 300-400 mi. E, we'd complete our 1995 analog with style.

[jojo762]

If only that upper low progged to sit over CA late next week into the weekend were shifted 300-400 mi. E, we'd complete our 1995 analog with style.

50-70kts of H5 flow over the central plains in early June sounds dreamy...

[nrgjeff]

This week is well handled in the short-term thread. After perhaps a relatively quiet 6-10 day, always some little local events in June, things may become more active again the middle of June. MJO is forecast to perk up in Region 4-5 by some models. Others have the MJO going back to sleep. Region 4-5 is favorable for a Pac NW trough. Even the models that put the MJO back to sleep introduce the said trough late in the 11-15 day period. All 3 agree on the feature. Jet stream energy punches into the Pac NW. Downstream ridge is depicted over the Upper Midwest. All of the above is favorable for the northern High Plains.

 

EDIT: June 4 probably needs to be added to the short-term thread dates. 12Z GFS/Euro both paint excellent chase days this Wednesday and Thursday. Moderate speed shear combines with high CAPE and quality low level turning. EML may finally limit junkvection and promote more chasable events.

[Ian]

Could be a good stretch up ahead with a few days off maybe. Gfs seems to like more than euro but euro is close. Been waiting for that 1995 redux after we leave.