2013 Chase - Tour 2 Countdown

[chionomaniac]

Excellent cars. They look big enough to carry all the ladies what nots... .

 

The current pattern may be enough to keep you busy until the end of the weekend but at that point it looks like a ridge could keep the plains quiet for a little while. So a big start coming up I feel. I bet you can't wait to see that first supercell, Paul.

[Paul Sherman]

Yep cant wait, should be some beautiful sculptured Supercells tomorrow, decent easterly path at 15-25mph as well, lovely easy chase to break us in. Noticing a probable High Plains chase middle to end of next week as well is possible but certainly could change at this point, there still has never been a tour that has not seen a Supercell so all bodes well for the season ahead, will probably be in Alabama by the end of the weekend  

[IanM]

It's hell out here - 1030am and the sunblock is on, cars are set, the gadgets are working. We think the guests are going to really like the new set up, especially the gr-earth info on the nav lap top.

[nsrobins]

12Z NAM for Weds. Umm. DL pushing back west at 00Z Thurs - thinking a target further West towards AMA may be in order with any cells that form on the DL/CF intersection capable of developing nicely so long as they tap into the better shear towards the Eastern panhandle/OK border.

Would it be totally unfair to treat just half of your guests to a preliminary Big Texan LOL?

[Paul Sherman]

Only if we get a Nado - You KNOW The rules  

[Dorsetbred]

When did that rule make it into the rulebook? I thought the year we hit the Big "T" was because we had no Nado's

[IanM]

And so the red meat consumption begins - a light snack to fuel us through the afternoon - yep, 2 x 1/4lb patties, a pile of pastrami and a little smoked turkey to top it off. Nap time...

[duckeyh]

When did that rule make it into the rulebook? I thought the year we hit the Big "T" was because we had no Nado's

 

I think we'd all given up by then . Anyway enough talk of "that" tour for this season   

Edited May 7, 2013 by duckeyh

[Tom Lynch]

As we count down to tour 3 it might be an idea to set a meeting point in T5 for all those people flying out on BA flight 193 Saturday 18th May.  Here is the place we have met at for the last two years,

The Crown Rivers (Wetherspoon)

 

key

A friendly, relaxing, family pub, offering great value and great British food. We offer a wide choice of ales, wines and ciders, plus a variety of international cuisine and British pub food classics, such as fish and chips and sausage and mash. We have something for everyone; so, while you wait for your flight, why not wait with us?

 

So , if all those people that are flying out on this flight want to meet up just post your name.  I will also arrange for the free bus to transport us from the airport to the Best Western, if that is where you are staying.

 

Tom

[ItIsGee]

As we count down to tour 3 it might be an idea to set a meeting point in T5 for all those people flying out on BA flight 193 Saturday 18th May.  Here is the place we have met at for the last two years,

The Crown Rivers (Wetherspoon)

 

key

A friendly, relaxing, family pub, offering great value and great British food. We offer a wide choice of ales, wines and ciders, plus a variety of international cuisine and British pub food classics, such as fish and chips and sausage and mash. We have something for everyone; so, while you wait for your flight, why not wait with us?

 

So , if all those people that are flying out on this flight want to meet up just post your name.  I will also arrange for the free bus to transport us from the airport to the Best Western, if that is where you are staying.

 

Tom

What time you getting to the air port for? i am not going to be there until 12 as my flight is at 3pm

[duckeyh]

I won't be joining you as I'll already be in Irving 

Edited May 8, 2013 by duckeyh

[chionomaniac]

Well the bonus chase day has a 5% risk area NW OK extending into KS. I suspect Paul will want to chase the southern end of the main risk area so that he is not too far away from the second set of arrivees.

 

 

 

 Tomorrow the main risk area is further south over mid TX.

 

[nsrobins]

05Z RAP in a little more detail suggests southern tip of risk area should provide adequate entertainment, with composite breaking out a cell around Altus OK at 21Z. The better wind vectors are further north but I like the DL potential in the southern region.
And it looks hot - 90F+ by mid afternoon.

Thurs is all about focii of big CAPE mid-TX region and chasing the micro-boundaries.

[chionomaniac]

05Z RAP in a little more detail suggests southern tip of risk area should provide adequate entertainment, with composite breaking out a cell around Altus OK at 21Z. The better wind vectors are further north but I like the DL potential in the southern region.

And it looks hot - 90F+ by mid afternoon.

Thurs is all about focii of big CAPE mid-TX region and chasing the micro-boundaries.

 You have said Altus for a few days now Neil, and that looks a good call to start off from.

[boomerang]

What time you getting to the air port for? i am not going to be there until 12 as my flight is at 3pm

We will be gone by then if things run smoothly.

Me and Mat will be meeting at Wetherspoons.

[nsrobins]

11Z RAP. Fine detail. The surface low to me looks a tad further east comparing 13Z RAP and actual conditions, but moisture, PW (1.25" - not bad at all) and surface vectors all look on track to get circa 60F dps into the target zone by 21Z.
On the slightly more advanced position of the DL and surface low I might think about the 183 around Frederick rather than Altus, then shuffle west if necessary.
Looking out at the cool cloudy afternoon here I would dearly love to be out there now.

[chionomaniac]

6Z NAM for 00Z looks promising for an isolated supercell that region:

 

 

 

 

 

[chionomaniac]

After a good start last night there should be an interest in mid to southern TX today and to a lesser extent tomorrow. Initially it was beginning to look poor for the rest of the tour, however, things are looking better for the middle of next week once the ridge clears west, allowing some moisture to return. Perhaps Paul will have enough time to show his guests the buried Cadillacs near Amarillo and, if they are really lucky, the floating mountain........

 

 

 

 

 ...DISCUSSION...
   MEDIUM-RANGE MODELS IN DECENT LARGE-SCALE AGREEMENT THROUGH THE
   PERIOD...THOUGH SMALLER-SCALE DIFFERENCES BEGIN TO EVOLVE LATE DAY
   ON DAY 5/EARLY DAY 6 -- I.E. NEXT WED. /5-15/.  DURING THIS TIME
   FRAME...REMNANTS OF THE CUT-OFF NWRN MEXICO LOW BEGIN EJECTING NEWD
   INTO THE SRN PLAINS.  SOME SEVERE THREAT COULD EXIST OVER THE SRN
   PLAINS WITH THE EJECTION OF THIS SYSTEM -- AND ALSO FARTHER N INTO
   THE WRN UPPER GREAT LAKES AREA IF THE GFS SOLUTION DEPICTING A
   SECOND SHORT-WAVE TROUGH PROVES MORE ACCURATE.  HOWEVER...QUESTIONS
   REGARDING SMALL-SCALE DETAILS DUE TO MODEL DIFFERENCES CAST DOUBT
   UPON BOTH DEGREE AND LOCATION OF ANY POSSIBLE THREAT -- THUS
   PRECLUDING ANY AREAL ISSUANCE ATTM. 
  
   DIFFERENCES IN HANDLING OF THIS EJECTING SYSTEM AS IT MOVES E OF THE
   MS RIVER CONTINUE THROUGH THE END OF THE PERIOD -- PRECLUDING ANY
   FORECAST CERTAINTY OVER THE ERN CONUS.  MODELS HOWEVER ARE IN BETTER
   AGREEMENT WITH THE INLAND ADVANCE OF A PACIFIC TROUGH DAYS
   7-8...WITH A SLOW INCREASE IN SEVERE POTENTIAL LIKELY TO BEGIN DAY 8
   OVER THE HIGH PLAINS.  SEVERE THREAT ASSOCIATED WITH THIS SYSTEM
   COULD EVENTUALLY WARRANT AREAL INCLUSION...BUT WITH THE MAIN THREAT
   CONFINED TO BEYOND THE FORECAST PERIOD /DAY 9 AND BEYOND PER THE
   CURRENT MODEL FORECASTS/...NO OUTLOOK AREAS WILL BE ISSUED FOR THIS
   SYSTEM ATTM.
 

 

 

 

http://www.spc.noaa.gov/products/exper/day4-8/

Edited May 10, 2013 by chionomaniac

[Tom Lynch]

What time you getting to the air port for? i am not going to be there until 12 as my flight is at 3pm

All things being well I should be getting in from Manchester around 9am just after Johnny H

 

Tom

I won't be joining you as I'll already be in Irving 

When do you arrive in Irving?

 

Tom

[chionomaniac]

Interest is growing towards the back end of tour 2 for potentially some action and even though it is still early days it is worth looking at the possibilities. Very frustratingly the timeframe for the greatest chance of any tornado potential lies across the changeover time between tours 2 and 3, however things can and do change.

 

For those on tour 3 asking on FB last week what to look out for regarding potential,  then the end of tour two demonstrates favourable conditions for supercells and possible tornados quite nicely.

The first chart that I look at is the jetstream chart with the surface pressure levels indicated. So let's look at the charts for 00z on the 19/5 -  5pm USA Central time zone.

 

 

Here we see the a surface based low pressure centrally over the upper plains with the jet stream ploughing into Kansas. This depression (or trough) has formed to the west of its current position and slowly drifted eastwards over the course of a couple of days. This has the effect of pulling warm moist air off the Gulf of Mexico across Texas towards Kansas.

 

 

The flow of these winds (green arrowed) can be seen at the surface and also in the form of a low level jet (LLJ) as the jet stream loses power over Kansas lower level winds are forced in to try and rebalance the pressure difference as demonstrated below:

 

 

When in Texas the LLJ can occasionally be demonstrated by low level cloud racing northwards.

 

I have also demarcated a red line on the surface wind map - this is an all important convergence zone where the strong southerly winds meet the northerlies coming around the back of the depression. The critical thing here is that the southerly based winds are full of moisture whereas the northerly winds are bone dry. This can be demonstrated by the dewpoint chart for that time.

 

 

With dew points in the 70's we have a lot of moisture building up over Kansas and a destabilising air mass as the trough moves eastwards. The dryline can be seen quite clearly where the contrast in dewpoints is greatest. With temperatures building impressively during the day 

 

 

and  a lot of energy held in the atmosphere (CAPE) 

 

 

then if the warm moist air can break through the warm dry air overlying it (the cap) then it can reach the colder air aloft and the explosive updraft can turn into a thunderstorm very quickly. And on the 18/19th these storms will be supercellular if these forecasts come true, and , with strong differing wind speeds at different layers of the atmosphere

 

 

( increasing the wind shear) then tornados will be a real possibility. Currently this is programmed to be somewhere over Kansas on the evening on the 18th - but with 6 days to go before this could come together, however a lot of model watching needed to see how this trough will interact with the plains ( it's slightly further west on the latest ECM - but critically there). Just why or why is this programmed for changeover eve?

 

 

 

 

 

 

[duckeyh]

[quote

When do you arrive in Irving?

 

Tom

[boomerang]

Thanks for info on the charts, really helpful.Just one question though.The charts have a time of 0.00hrs 19/5......isnt that 6pm on the 18th USA time?

Edit .I've now read your post completely and it is the evening of 18th.Which isnt change over day thats the 19th.We fly in on the 18th.Wonder if we can get them to do a detour.

Edited May 12, 2013 by boomerang

[chionomaniac]

Thanks for info on the charts, really helpful.Just one question though.The charts have a time of 0.00hrs 19/5......isnt that 6pm on the 18th USA time?

Yes, probably, they always confuse me! - the charts are in zulu time or GMT (not BST) so American CST is GMT- 5hrs currently.

[chionomaniac]

Edit .I've now read your post completely and it is the evening of 18th.Which isnt change over day thats the 19th.We fly in on the 18th.Wonder if we can get them to do a detour.

Of course the problem with it being the evening of the 18th is the logistics of getting everybody back for their flights on time (19th) from tour 2 whilst trying not to miss any potential action. And if you have got in a day early in preparation then you may be out of luck as if I was on tour 2 I would already be twisting arms to leave Kansas as late a possible to get back to DFW. Bloomin' annoying timing as sitting in the BW at Irving on 18th knowing that there could be a twister fest in Kansas would be highly frustrating.. Still plenty of time for that trough to stall further west which would be better for tour 3 or push through quicker which would benefit tour 2.

[Chris Sargent]

All things being well I should be getting in from Manchester around 9am just after Johnny H

 

Hey all,

 

I'm flying Manchester to LHR at 0830 Saturday morning. Heading into JFK and from there to DFW. Only doing that weird route as I'll be spending a few days in NYC after the tour with my GF.

Really cant wait now and 4 - 8 day outlook starting to look better for the 19th onwards.

 

Boomerang - you're just round the corner from me... I'm in Rocester, Staffs ... Oh and I work at Alton Towers so can imagine the queues at customs!!

 

Chris