04/20/05 FCST: South/Central/High Plains

[Karen Politte]

Well, maybe it's time to save the sanity of those amongst us who live in the Southern Plains and try and put out a forecast for the first time in a while. The crystal ball prophecies lead me to post this for the 0Z Wed 20th April timeframe......

GFS has a small wave coming through the KS/OK/TX areas by this time. What is encouraging is that this is forecast to perhaps lean on the open-wave style of system - rather than the closed bowling balls we have seen of late. I'd much prefer to chase a more classical setup with a nice, broad open wave.......and while this one may not be too broad and the flow looks limited, there is still a long time to go before the models really have a handle on it.

A big concern is the rapid generation of a HI that sinks down into SW KS around this timeframe, also. :?

On the upside, the GFS's take on things forecasts dewpoints in much more abundance than we have seen so far this year - with 60's all the way up into Kansas.

As far as upper flow, it's currently looking like the TX/OK Panhandles may be under the gun.

Any takers/speculators?

KR

 

[Mike Johnston]

Karen, can see the more classic open low on the model you are looking at. However, looks to me like the strongest & divergent jet is still well south over Mexico. Is this what you are referring to re: upper flow, or am I missing something? BTW - I am a novice forecaster, let alone long-range forecaster, but I do enjoy reading the comments of yours and others who are looking ahead.

Interesting with the higher dewpoints; especially in light of Jeff Snyder's comments over in the other forum re: return flow being more of the recycled continental air rather than the true tropical variety, in light of the position of the high over SE CONUS in the days leading up to the target date. Perhaps we can begin to expect solar heating to compensate for such an effect?

 

[Karen Politte]

Originally posted by Mike Johnston
BTW - I am a novice forecaster, let alone long-range forecaster, but I do enjoy reading the comments of yours and others who are looking ahead.

Mike - you and me both! :lol: I am by no means the most experienced/intelligent forecaster on here.....and sometimes I just open my mouth and let my belly rumble.

Here is the upper-airflow pattern I am referencing at the 500mb level of the atmosphere:

>>Image Removed<<

500mb is where we frequently have a habit of looking when we are searching for upper systems coming into our region for chaseable storms. At this time of year - we look for southwesterlies at 500mb in some sort of jet streak or strong flow pattern to suggest to us that a system is manifesting itself - perhaps. Seeing the constant toughiness in the GoM is concerning also - but I think that the upcoming system next week (whenever it happens) might have a better chance at getting this problem erradicated to a certain degree.

I'm sure there are more knowledgeable folks on here who could chime in about all this.......that moisture next week looks better but probably *NOT* true caribbean juice. But you have to take what you're given, I'm afraid.

KR

 

[Mike Johnston]

Thanks so much - now I see it. I was looking at 250mb 24 hours earlier.

 

[Bobby Eddins]

Looks like the 12z run is now beginning to close off this low and drift it to the northern plains.

[Broken External Image]:http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/12/images/gfs_500_156m.gif

still looks like some potential and after this system it looks like the STJ returns to the splains along with some open waves. Good time may be coming.

[Broken External Image]:http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/12/images/gfs_250_216m.gif

 

[Adam Atkins]

4/20

The setup for next wednesday will likely change plenty of times. Here's why I think severe weather will be limited to a small area along the gulf of Mexico. Tuesday night might be stormy across the southern plains in the form of a squall line that develops along a surface cold front diving southward. The 850mb 0 degree isotherm makes its way into N OK, not very pleasant for mid-April, after the cold front has passed. The surface features don't seem to be collocated with upper level support this go-around. The OUNAFD mentioned heavy rain to be the primary threat in this neck of the woods, probably due to the surface low along the gulf leading to strong isentropic ascent and latent heat release in conjunction with the surface frontal boundary.

The gulf coast may see one of the 1500 J/Kg CAPE days under complete cloudiness and have a moderate risk issued, solely because of the lack of any sort of cap.

On the plus side, April showers bring May winter wheat so we can get the evapotranspiration started and some higher Td's during the day here in OK. It seems the models have been picking up on this phenomenon in the high plains early next week, which could lead to some neat storms.

 

[Karen Politte]

The waters are a bit muddy for the middle of next week - hence, I guess, why nobody else's taking the plunge with some speculation. So I'll have a go again to at least keep the engine running.....

There seems the potential for severe weather for the timeframe Tuesday April 19th through Thursday April 21st next week. I am thinking that Tuesday may just be too soon for this coming system - but we shall see. The GFS currently has it stuck out over Nevada/Utah on Tuesday, poised to come out the next day.

The ETA doesn't have this period in its sights yet and so the only guidance will be the GFS. I'm not too enthused with the ETA's record of handling these systems so far this year anyways - and so I am quite happy to live in the technicolor land of the GFS for now. One thing that IS evident is that this system will likely be some kind of closed-off low, yet again. It's getting boring, I know - but if it's the first chance in over a week and the last chance in just as long after then - I think we're all going to have to take a stab at it. The closed-low may take on a sort of neutral/negative-tilt characteristic as it comes out on Wednewday/Thursday - so that isn't all bad.

One encouraging thing is the GFS' predictions of mositure availability. Although - as many have discussed - it's highly unlikely to be the true Caribbean juice we are looking for - it WILL be present in greater quantities than previously - albeit modified. 60-degree dewpoints are STILL forecast to be available into Kansas - with the 65oF line teasing us around the Red River. I will have to look more in-depth at current moisture values in the Gulf......

Wednesday April 20th's area to watch may be just east of the surface low in western Kansas - but the positioning of this will almost certainly change with time. If the winds can stay backed sufficiently and the upper support is there - a jaunt into the OK/TX Panhandles for the dryline may also not be out of the question (assuming the mositure makes it that far west - whch it might not).

Just a wishcast - nothing more.

KR

 

[Karen Politte]

Wow.....sheesh I'm the only one sticking my neck out, huh?

Well - the 12z GFS paints an interesting picture. I know you all probably aren't too bothered until like the end of the weekend or so - but the sad fact of the matter is that I have to forecast like this to some degree......as I need advance time to ask off work etc. etc.

Here is what the 12Z GFS shows for 00Z Friday 22nd April (Thursday 21st April 6PM CDT):



It doesn't take much figuring to imagine that I'm vaguely excited, if this ever came to verify (yeah, right). Nice little jet max streaking across into SWrn KS/OK/tx Panhandles. It almost made me drool.

The moisture for this time period looks a bit grim - with the moisture axis too far east as I had feared. This may be one of those heartbreaking situations whereby it's a case of "what could have been if the moisture had made it".......

MSLP does make me smile somewhat, though - hinting at a nice low in Wrn KS with plenty of backed winds northeast of the low as well as down along the dryline (maybe).

We'll see......in the meantime, I will remain.

KR

 

[Mike Johnston]

Looks like we could have pretty steep lapse rates over the western KS and panhandle areas also. Share your concern about moisture, though, especially w/ the high surface temps.

 

[Gabe Garfield]

Wow.....sheesh I'm the only one sticking my neck out, huh?

Looks good to me! If that verifies, we'll be in business.

Gabe

 

[Justin Walker]

MSLP does make me smile somewhat, though - hinting at a nice low in Wrn KS with plenty of backed winds northeast of the low as well as down along the dryline (maybe).

We'll see......in the meantime, I will remain.

KR

I'm in agreement with the few you have stuck their necks out. This system is beginning to look better. The winds look good throughout but the limiting factor will be the modified gulf air. But hey...it's April, low to mid 60's will do for me. As of now...I am clearing my schedule for Wednesday and hopefully will dry to play the dryline!! 8)

 

[Mikey Gribble]

I think there is a decent chance of severe weather in SW Kansas and the panhandles on Wednesday, but the upper level winds are pretty pathetic. We might need to open up a fcst thread for the 21st before too long. Thursday is looking like it might shape up to be the best day in the plains with this system. Time will tell.

 

[Tony Laubach]

Still a very long way's out, but the 12z GFS seems to be hinting at a dryline bulge in West Central/Central Kansas... and most of us remember what happened there last time.

In an email exchange with Chris Rozoff (who points out the bulge), he's like me in saying something too soon, but if I were to reach out, I'd be playing Southwest Kansas with room to move south or north.

I think the moisture is gonna finally start being less and less of an issue as it seems the models are indicating good flow from the Gulf into the Plains (looking earlier this morning). But as mentioned above, the winds look kind of crappy...

This, still, is very far out, but worth a look. Hoping the winds inprove and some more GULF moisture can stream up. Looks like half of it will work its way in!

 

[Mikey Gribble]

Thursday just fell apart with the OOZ run. Wednesday looks pretty much the same with the surface low a little farther South. 30-40 knot flow at 250mb does not get me very excited. The directional shear looks great. Speed shear is a completely different story though. I don't see much of a problem as far as moisture is concerned IMO. I am definitely not pumped about this setup, but I am thinking this is probably going to be our last warm-up chase before the real season starts at the very end of the month so I will probably end up going regardless.

 

[Karen Politte]

A) I wouldn't judge anything by what this morning's models were saying, B) I see a lot of energy and potential with this next system and C) I would tune into the 0Z GFS run currently being issued. I think this morning's run was a burp in what otherwise may be a forecasted interesting event for TX/OK/KS this coming week.

However the above probably isn't too important - as most on here don't seem very enthused about discussing chasing potential if it's any further south than central KS.

KR