The future of the season....

[Dan Robinson]

How quickly things change. Just a couple of days ago, we thought that this weekend was definately going to be out as far as leaving for the Plains, and that it was 'safe' to make other plans through Sunday (work, etc) and so we did (life has to go on, even during storm season). That's probably going to cost us Monday's prospects, sigh. The models seem to react when I make absolute statements about our plans. Maybe that's the trick on how to deal with future Omegas and death ridges.

So for now, Lord willing and barring a catastrophic shift of the pattern, we are planning on possibly heading out of here maybe early Monday morning to perhaps start this long-awaited trip, hopefully. Notice the emphasized caveats preventing that from being an absolute statement.

 

[Stan Rose]

well, the 00Z NAM continues to show a sub 1000 low over E NE on Sat, with its way-overdone dewpts resulting in CAPE over 5000 :lol: So, some continuity. Course, it's also horribly capped. Watching the last couple days' runs struggle with the eventual 'pattern change' has me convinced that it is shear folly (pun intended) to pay much attention beyond 24 hours.

 

[Marc Austin]

Well thank God for small miracles! Things have taken a turn for the better. Best not to open my mouth and jinx the whole darn thing though. I'm just hoping for a dark cloud or two and possibly even a lightning bolt!

I have to admit though, I don't see anything on Sat, May 20. Is there supposed to be something over NE on that day or the following Saturday? I'm confused, but that's actually typical...

Best of luck to those who are chasing and for those of you who have travelled from other countries... I think you might just be in for a show this next week.

 

[Dan Robinson]

 

[Matthew Crowther]

OMG a good block! :lol: :lol:

 

[Stan Rose]

I have to admit though, I don't see anything on Sat, May 20. Is there supposed to be something over NE on that day or the following Saturday? I'm confused, but that's actually typical...

[/b]

Yes, THIS Saturday. Both the gfs and nam have a 998/99 low over NE or KS, with sb CAPE of 2K+ off to the east. IF 60 dewpoints show up friday in the lower Miss, mid to upper 60s would not be unreasonable for the Missouri on Sat.
But 700 temps of 12 degrees kinda negates all that :lol:
My only point is that a day or two ago, no way would anyone have even fathomed anything resembling a surface low out there in model land on Saturday. Which is why i wouldnt be planning my chase targets for day 2 let alone day 7!

 

[Jeff Snyder]

Just as a reality check... As I wrote about in my blog, the buoys in the Gulf of Mexico and the northwestern Caribbean are certainly showing the effects of the strong frontal passage / continental air intrusion that occurred a few days ago.

The Gulf has been raked several times in the past 10 days, so the quality of the moisture is yet to be seen. BRO, LCH, and CRP soundings continue to show seasonably dry low-level moisture profiles, which is not surprising given the FROPAs from the past week or two. Buoy 42055, located very near the Bay of Campeche, is only indicating a dewpoint of 57F right now, a full 18F degrees lower than last weekend! Farther to the southeast, buoy 42056, south of the Yucatan - Cuba pass, is currently reading a dewpoint of only 69F, which is a full 10F lower than only a couple of days ago. There are other buoys in the Gulf that are showing 57-62F dewpoints, for what it's worth.

Sure, the waters are relatively warm this time of year, so the cP airmass will modify. In addition, vegetation has moved out of dormancy, so there will be contributions from evapotranspiration. Unfortunately, with 700-850mb as hot as they will be, we will need all the low-level moisture we can get to even have much of a chance of daytime, surface-based convection. Given that 70F dewpoints are locked well into the Caribbean, I have a very hard time any there will be any dewpoints anywhere near 70F in a couple of days, particularly north of I70 (or I-20 for that matter). For that matter, I can't imagine we'll see any sort of deep, Gulf moisture until, maybe, early next week. Looking at the model forecasts, it doesn't look like the Gulf moisture will make it north of I20 until the middle parts of next week. As another complication, with a surface high progged to meander around the northeastern Gulf of Mexico, surface flow looks like it'll be from the east across the eastern portions of the Gulf, which may yield more of a 'modified continental airmass' situation. Again, some modification will occur, but a look at the 850mb dewpoint forecasts shows that much of the moisture will be shallow until at least next Tuesday. The 24hr forecast from tonight's 0z NAM run is calling for >70F dewpoints across the northwestern Gulf tomorrow evening. To this forecast, I laugh. Call me a pessimist.

 

[Matthew Crowther]

Just as a reality check... As I wrote about in my blog, the buoys in the Gulf of Mexico and the northwestern Caribbean are certainly showing the effects of the strong frontal passage / continental air intrusion that occurred a few days ago. [/b]

I agree that the moisture could be a problem for any Monday/Tuesday chasing prospects- but I will point out that most folks here are so desperate for any supercellular action after the last two weeks of nothingness, that any type of reasonably structured supercell will be most welcomed (I know that would satisfy me at this point).

The real question to my mind is what will the pattern do after the first closed low off the West Coast ejects into the Plains and flattens the long-wave ridge that has been bedeviling us for the past week. The new GFS control is pretty optimistic with good WSW flow over the Plains for quite a few days next week and into the weekend. The ECMWF is less aggressive, with higher heights and weaker flow. I am worried that another low is forecast to form at about 140W later in the period- this is usually not a good place for a upper vortex to camp out. Luckily, at least this low is supposed to have a good fast westerly flow underneath it, which should allow the Rockies ridge to stay relatively deamplified with some flow over the High Plains. So the bottom line I guess is: the pattern will get better, but will it only be a marginal pattern for possible tornadic action? Time will tell. Maybe the 0Z GFS ensembles will shed some light on a still murky situation.

 

[Mark Farnik]

The 00Z GFS model Dan posted shows some really nice looking 500 mb flow right over my stomping grounds on Tuesday! It's good to see west/southwesterly flow again! But like everyone has been saying, moisture return from the GoM could be the biggest problem. But if for some strange reason we actually could get some decent moisture to make it up to this area by late Tuesday afternoon, we could be in buisness! And plus I get out of school 3 days early on Tuesday afternoon as a reward for doing well on my CSAP state testing, so it would be a perfect chasing situation for me! Yes, I know deep down in my heart that the best moisture probably won't make it in time, but I can always hope, can't I? SDS is setting in again after a MONTH without seeing ANY thunderstorms! The last thunderstorm we had in northeastern CO was on April 23rd! I'd love to see tornadic supercells here in the High Plains as much as the next guy, but at this point of desperation even some nicely structured supercells would be very welcome!
M Crowther said

I agree that the moisture could be a problem for any Monday/Tuesday chasing prospects- but I will point out that most folks here are so desperate for any supercellular action after the last two weeks of nothingness, that any type of reasonably structured supercell will be most welcomed (I know that would satisfy me at this point).[/b]

Amen to that! You nailed that right on the head! As the lion said in 'The Wizard of Oz': "Ain't it the truth, ain't it the truth!"
I have a feeling that if we can even get dewpoints in the low 50's up into eastern CO/western KS/western NE , there might be a decent chance of a severe weather outbreak over the western High Plains on Tuesday. There are no weather features forecast at this point that could halt or regress the moisture from marching north over the Heartland, so that's one positive aspect of this situation. It's still five days out, so we'll just have to keep our fingers crossed that the gulf moisture makes it far enough north in time and the forecasted flow pattern stays on track. B)

 

[joel ewing]

This topic makes me recall a conversation I had a good 15 yrs. or more with one of the old-timers at the North Platte NWS office. I had gone in there in somewhat of a panic, as this particular day had all the parameters in place..except that the dews were in the very upper 40s / low 50's. He could see by my body language that I was stressed about the low numbers. He turned around in his chair to face me....reclined back..and in his western drawl that sounded entirely like Festus from that old show Gunsmoke..."Yew gotta understannnd.....around heeeeree it don' take muuch!
Later that afternoon....the atmosphere exploded!

[q


uote name='Mark Farnik' date='May 18 2006, 11:53 AM' post='126423']
The 00Z GFS model Dan posted shows some really nice looking 500 mb flow right over my stomping grounds on Tuesday! It's good to see west/southwesterly flow again! But like everyone has been saying, moisture return from the GoM could be the biggest problem. But if for some strange reason we actually could get some decent moisture to make it up to this area by late Tuesday afternoon, we could be in buisness! And plus I get out of school 3 days early on Tuesday afternoon as a reward for doing well on my CSAP state testing, so it would be a perfect chasing situation for me! Yes, I know deep down in my heart that the best moisture probably won't make it in time, but I can always hope, can't I? SDS is setting in again after a MONTH without seeing ANY thunderstorms! The last thunderstorm we had in northeastern CO was on April 23rd! I'd love to see tornadic supercells here in the High Plains as much as the next guy, but at this point of desperation even some nicely structured supercells would be very welcome!
M Crowther said

Amen to that! You nailed that right on the head! As the lion said in 'The Wizard of Oz': "Ain't it the truth, ain't it the truth!"
I have a feeling that if we can even get dewpoints in the low 50's up into eastern CO/western KS/western NE , there might be a decent chance of a severe weather outbreak over the western High Plains on Tuesday. There are no weather features forecast at this point that could halt or regress the moisture from marching north over the Heartland, so that's one positive aspect of this situation. It's still five days out, so we'll just have to keep our fingers crossed that the gulf moisture makes it far enough north in time and the forecasted flow pattern stays on track. B)
[/quote]

 

[John Hudson]

Yeah, the whole GFS for Tuesday has "OMEGA" written all over it, but I must admit that so far, I like what I see happening in the western Dakotas. There is a nice SW flow established, and the 00Z GFS shows SBCAPE with values of >2500J/kg. Although the cap is tight, maybe SFC temps of 75+ will be enough to set things in motion?

I know the GoM has been significantly sponged off, but isn't a little moisture advection better than nothing? It's a better setup than I've seen in an awful long time. So, I'm gonna be there.

John
VE4 JTH

 

[Chris Hayes]

I have through next friday to chase. I'm to the point now where if I see lots of good storm structure, (something I didnt even see in 2005), I'll be happy. It is nice to see chase chances coming up for at least a few days during the next week. I dont think we'll have a very hard time getting at least 50s dewpoints in the Dakotas and NE by Monday and Tuesday. Dewpoints in that area are a little "higher" already, with 40s dewpoints common over the western Dakotas. Dewpoint depressions will be higher than I'd like to see, but it might be enough to squeeze out some decent storms. I don't see, (even though I'm not an expert forecaster), any big outbreak days on the way for next week. I'll be happy if we can get some isolated LPs going each day As long as I have a better chase season than I did last year, I'll go home happy. I'm still coming out here in June next year. I've had it with May. Very overrated. I'm in Salina, Kansas right now.

 

[Mike Hollingshead]

Has anyone looked at Wednesday on the GFS yet? That would be nice if that worked out like that.

I think the gfs has been doing a pretty good job with the last week+ overall. Some sort of energy will have to come out from the west sooner or later. I would think by Wednesday we'd have workable dews in place.

 

[Gabe Garfield]

Has anyone looked at Wednesday on the GFS yet? That would be nice if that worked out like that.

I think the gfs has been doing a pretty good job with the last week+ overall. Some sort of energy will have to come out from the west sooner or later. I would think by Wednesday we'd have workable dews in place.
[/b]

That's a heckuva setup, if we can get it to verify. Major concern ATTM is moisture. If we can get the good stuff up this way, it'll be a big day (provided the kinematics work out as advertised). Reminds me a little bit of 5/22/04.

Gabe

 

[Matthew Crowther]

Careful- the models really begin to differ after 120 hours- the 12Z run of the GFS ensembles are all over the place, and the 12Z ECMWF really start to differ from the GFS by Tuesday. This situation is not going to really resolve itself for at least several more model runs.