Model Watch For Tour 1

[icbinb]

Nah, think Mikel Nimbus might be on your flight.

So far I've found nobody on mine

I'm also on the BA flight Harry. I think that makes three of us.

[Arron]

Hey Smokes. As Harry said, I'm flying AA aswell so I may be holding on to dear life on the same flight as you. Supposed to land at DFW at 5.20 from Chicago. Thinking about it, I hope that's not too late and the airport is shut due to bad weather. :s

Ah I'm on the direct one at 12:15pm, AA81 I believe

[Harry]

I'm also on the BA flight Harry. I think that makes three of us.

Aha, wicked! I'm not going to be a loner then :blink:

Could we exchange mobiles via PM, then we can meet up at the terminal as opposed to sitting in the corner, looking round going "is that him?" lol

[Nick F]

I'm not entirely confident with interpreting US weather charts and their accuracy, but I am very aware of the GFS ability to overcook things a week in advance! Is that even possible though? 3500J/Kg CAPE with Lifted Indices of -8 at MIDNIGHT on Wednesday 28th April???

If so, and that kind of thing comes off, we could be in for a real treat the day we land, providing we'd go off chasing the day we get there

Does look good, 3000+ j/kg CAPE is not unusual. As Paul infered above for Greensburg day, for example the NAM/WRF forecast of CAPE for the evening of 4 May 2007, when the Greensburg Kansas tornado occurred, had an impressive 3500-4500 J/kg of CAPE over western Oklahoma pointing into southwest Kansas ahead of a surface dryline:

[Paul Sherman]

1st Chase Day for Tour 1 now into the Lower Resolution of the GFS Model.

Looking like we "might" hit the ground running on Wednesday 28th April, after that we would probably have to follow the system Further East into Missouri or Iowa etc for the following 2 days, but all that is subject to change.

- Watch Out Kansas

- Cape upto 1,600jkg

988 Low is pretty damn Low for this time of year.

Paul S

[Gorky]

12z today looks good again for some great storms for Tour 1. I like the consistency which is starting to appear. Also, just getting the 7th in at T384 now and there is a nice trough pushing into Texas that day. I could have a bumpy landing as that's the day my trip starts! (Yay for 384 hour predictions )

[dogs32]

384 hour predictions..lol....I like it Nathan...

far away though but just to see something makes you feel happy

Paul we are already looking faaaaaaarrrr ahead...lol

Storm Is a Slow-Mover

However, there is concern of a more significant and dangerous severe thunderstorm and tornado outbreak late in the week and this coming weekend over the Plains. :bomb: :bomb:

Edited April 21, 2010 by dogs32

[Tom Lynch]

Does look good, 3000+ j/kg CAPE is not unusual. As Paul infered above for Greensburg day, for example the NAM/WRF forecast of CAPE for the evening of 4 May 2007, when the Greensburg Kansas tornado occurred, had an impressive 3500-4500 J/kg of CAPE over western Oklahoma pointing into southwest Kansas ahead of a surface dryline:

Ah yes I remember the day well it was flippin hot too . We met up with the Outlaw Chasers they played frisby in the car park and shared their BBQ pork ribs. Later in the evening after Greensburg had been hit we sat behind one tornado that was about 1.5miles wide. The inflow was pulling our van even with the handbrake on. It was dark ,we couldn't see anything and so headeded of the Pratt to find a bed for the night.

Tom

[Paul Sherman]

Model Update

The good thing is the 00z is still showing a very good trend with Multiple Chase Days

GFS Has now as I expected slowed down the System for the Wed 28th April, instead bringing it out across the Plains around Friday 30th. This is not a bad thing as we could get multiple Chase Days now instead of the Low ploughing straight across towards the East Coast.

- Wed 28th April

- Thur 29th April

- Friday 30th April

After that the pattern still looks very good all the way into the following week!

Paul S

[Nick F]

Yes, latter half of next week looking good still. Befiore then, after the current system takes severe weather east of the Mississippi, it looks as though severe weather will become less likely early next week as the flow becomes more zonal and from the W or NW pushing gulf moisture back south early next week with more ridging. However, another deep trough amplifies as it swings in off the Calfornian coast by mid-week, and ECM also shows this slowing as it reaches to the west of Plains. Thursday looks a good day, though a long-way off, with a lee cyclone east of the Rockies, falling heights from the west as trough approaches and strong LLJ (shown by 850mb winds) which will transport quality moisture north across the Plains.

After Thursday, another upper trough arriving from west on ECM, so perhaps a continuation of severe weather:

[Paul Sherman]

Get In There

Nick could have written the SPC 4-8 Day Updated Forecast from his post above.

SPC Now Highlighting the Fact that the 1st Chase Day for Team 1 Will almost certainly be Thursday 29th April (Paducah Day Last Year )

-------------------------------------------------------------------------------------------

DAY 4-8 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0345 AM CDT THU APR 22 2010

VALID 251200Z - 301200Z

...DISCUSSION...

SEVERE WEATHER FOCUS IS ON THE MIDDLE AND SRN ATLANTIC

COAST/SOUTHEAST U.S. DAY 4 /SUN. APR. 25/...WHERE MEDIUM-RANGE

MODELS DEPICT CONTINUED EWD ADVANCEMENT OF THE SURFACE COLD FRONT

TOWARD -- AND EVENTUALLY OFF -- THE MIDDLE AND SRN ATLANTIC COAST.

VERY STRONG FLOW ALOFT IS FORECAST TO REMAIN ATOP THE WARM

SECTOR...PROVIDING SHEAR FAVORABLE FOR SUPERCELLS. THIS COMBINED

WITH A MOIST ENVIRONMENT DESTABILIZING THROUGH THE AFTERNOON APPEARS

SUPPORTIVE OF THE POTENTIAL FOR WIDESPREAD SEVERE WEATHER ACROSS

THIS AREA.

BY DAY 5 /MON. APR. 26/...THE FRONT WILL LIKELY HAVE MOVED WELL OFF

THE ATLANTIC COAST. WHILE THE TRAILING PORTION OF THE BOUNDARY

SHOULD BE SHIFTING SWD ACROSS THE FL PENINSULA...WEAK LAPSE RATES

ARE INDICATED -- SUGGESTING POTENTIAL FOR DESTABILIZATION WILL BE

LIMITED. THUS -- DESPITE ENHANCED FLOW ALOFT...CONFIDENCE IN

SIGNIFICANT SEVERE WEATHER REMAINS RATHER LOW ATTM.

AS THE MAIN ERN U.S. UPPER TROUGH APPROACHES THE ATLANTIC COAST DAY

5 BUT LINGERS OVER ERN CANADA/NEW ENGLAND...THE NEXT MAJOR

TROUGH/LOW IS FORECAST TO DIG SEWD ACROSS THE WRN U.S. TOWARD THE

DESERT SW THROUGH DAY 7 /WED. APR. 28/. THE GFS AND ECMWF -- WHILE

DIFFERENT IN THE DETAILS...AGREE THAT THIS LOW/TROUGH SHOULD MOVE

EWD DAY 8...WITH AN EXPANDING CENTRAL/SRN PLAINS WARM SECTOR

EVOLVING EAST OF LEE CYCLOGENESIS. THIS SUGGESTS INCREASING SEVERE

POTENTIAL INTO/THROUGH DAY 8 /THU. APR. 29/...BUT ATTM CONFIDENCE IN

THIS EVOLUTION IS NOT SUFFICIENT TO WARRANT THE INTRODUCTION OF A

THREAT AREA.

[dogs32]

Get In There

Nick could have written the SPC 4-8 Day Updated Forecast from his post above.

SPC Now Highlighting the Fact that the 1st Chase Day for Team 1 Will almost certainly be Thursday 29th April (Paducah Day Last Year )

-------------------------------------------------------------------------------------------

DAY 4-8 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0345 AM CDT THU APR 22 2010

VALID 251200Z - 301200Z

...DISCUSSION...

SEVERE WEATHER FOCUS IS ON THE MIDDLE AND SRN ATLANTIC

COAST/SOUTHEAST U.S. DAY 4 /SUN. APR. 25/...WHERE MEDIUM-RANGE

MODELS DEPICT CONTINUED EWD ADVANCEMENT OF THE SURFACE COLD FRONT

TOWARD -- AND EVENTUALLY OFF -- THE MIDDLE AND SRN ATLANTIC COAST.

VERY STRONG FLOW ALOFT IS FORECAST TO REMAIN ATOP THE WARM

SECTOR...PROVIDING SHEAR FAVORABLE FOR SUPERCELLS. THIS COMBINED

WITH A MOIST ENVIRONMENT DESTABILIZING THROUGH THE AFTERNOON APPEARS

SUPPORTIVE OF THE POTENTIAL FOR WIDESPREAD SEVERE WEATHER ACROSS

THIS AREA.

BY DAY 5 /MON. APR. 26/...THE FRONT WILL LIKELY HAVE MOVED WELL OFF

THE ATLANTIC COAST. WHILE THE TRAILING PORTION OF THE BOUNDARY

SHOULD BE SHIFTING SWD ACROSS THE FL PENINSULA...WEAK LAPSE RATES

ARE INDICATED -- SUGGESTING POTENTIAL FOR DESTABILIZATION WILL BE

LIMITED. THUS -- DESPITE ENHANCED FLOW ALOFT...CONFIDENCE IN

SIGNIFICANT SEVERE WEATHER REMAINS RATHER LOW ATTM.

AS THE MAIN ERN U.S. UPPER TROUGH APPROACHES THE ATLANTIC COAST DAY

5 BUT LINGERS OVER ERN CANADA/NEW ENGLAND...THE NEXT MAJOR

TROUGH/LOW IS FORECAST TO DIG SEWD ACROSS THE WRN U.S. TOWARD THE

DESERT SW THROUGH DAY 7 /WED. APR. 28/. THE GFS AND ECMWF -- WHILE

DIFFERENT IN THE DETAILS...AGREE THAT THIS LOW/TROUGH SHOULD MOVE

EWD DAY 8...WITH AN EXPANDING CENTRAL/SRN PLAINS WARM SECTOR

EVOLVING EAST OF LEE CYCLOGENESIS. THIS SUGGESTS INCREASING SEVERE

POTENTIAL INTO/THROUGH DAY 8 /THU. APR. 29/...BUT ATTM CONFIDENCE IN

THIS EVOLUTION IS NOT SUFFICIENT TO WARRANT THE INTRODUCTION OF A

THREAT AREA.

Edited April 22, 2010 by dogs32

[Paul Sherman]

Lol

Just viewed the 06z GFS

If that verified it would wipe most of Kansas and Oklahoma off the Map

BTW: Have never seen a Tornado in the Month of April so I am Hoping the Set-Up is a good un

[kold weather]

Yeah models looking very decent now which is very good to see, as has been said already the current upper trough that is bringing the instality in the next few days will move off and leave a stable pattern behind it which will hinder instablity for a few days. After this has pushed through another upper trough feature digs down and the jet streak comes up through the plains with a high instablity set-up.

Without a doubt the period from the 28-31st is looking good right now, certainly could be a moderate type set-up IMO once it comes to the time.

[Paul Sherman]

Haha

Thursday 29th is once again off the scale

This is looking awesome

[Arron]

good grief!

[Paul Sherman]

Day 4 Of Tour 1 Looks..........well Interesting

-

Wednesday now looks like a Slim chance of some Ordinary Thunderstorms with Cape Building

Thursday 29th Still On for 1st Proper Risk Day!

Paul S

[dogs32]

Day 4 Of Tour 1 Looks..........well Interesting

-

Wednesday now looks like a Slim chance of some Ordinary Thunderstorms with Cape Building

Thursday 29th Still On for 1st Proper Risk Day!

Paul S

lol

Jet lovely placed to suck up some nice warm moisture

Puts the UK Storm Potentail to shame. :lol:

can you imagine having the same large area of CAPE for the UK

Edited April 23, 2010 by dogs32

[Harry]

Funny that our christmas' feel like they've come at once when we get CAPE in the region of 1000J/Kg and LIs of -3 to -4.

3500J/Kg with LIs of -9 - HA

[Paul Sherman]

Unfortunately Downgrades starting to appear on the SPC Outlook for our first 3 days of Chasing

Looks like the Timing is all out for this Large Trough with the Moisture and Set-Up not tying in favourably.

So it looks like we will have ample Moisture come Thursday but it may all go to waste as the System Closes Off further North.

Lets hope the Models change over the next 3-4 days

DAY 4-8 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0341 AM CDT FRI APR 23 2010

VALID 261200Z - 011200Z

...DISCUSSION...

00Z ECMWF/GFS GUIDANCE REMAINS IN GOOD AGREEMENT IN THE DEVELOPMENT

OF ANOTHER SIGNIFICANT UPPER-LEVEL TROUGH OVER THE WRN U.S. ON DAY 5

/TUE APR 27TH/. THIS TROUGH WILL BE MAINTAINED OVER THE WRN STATES

THROUGH THE REMAINDER OF THE EXTENDED PERIOD...THOUGH A SIGNIFICANT

SHORT WAVE TROUGH WILL EJECT NEWD FROM THE PARENT SYSTEM...

EVENTUALLY FORMING A CLOSED LOW OVER THE N-CNTRL CONUS ON DAYS 6 AND

7 /WED APR 28TH AND THU APR 29TH/.

THESE MODEL DATA SUGGEST THAT MOISTURE WILL INITIALLY BE QUITE

LIMITED AHEAD OF THE ASSOCIATED SURFACE FRONTAL SYSTEM ON DAYS 5 AND

6. BY DAY 7...IT APPEARS THAT AN AXIS OF RICH BOUNDARY LAYER

MOISTURE WILL DEVELOP NWD INTO THE SRN PLAINS. HOWEVER BY THIS

TIME...THE LEAD IMPULSE WILL HAVE ALREADY CLOSED OFF OVER THE

N-CNTRL CONUS.

CURRENTLY...IT APPEARS THAT THE DYNAMIC FORCING FOR ASCENT WILL

REMAIN TO THE N OF THE MORE MOIST AND UNSTABLE AIR

MASS...EFFECTIVELY LIMITING THE POTENTIAL FOR A MORE WIDESPREAD

SEVERE WEATHER EPISODE. THEREFORE...NO AREAS WILL BE DELINEATED IN

THIS FORECAST.

[Paul Sherman]

Lol

Just need to clear up my post a bit after being lambasted by Mr Hanrahan on the Phone FOR Sounding Negative

The Set-Up will still yield Chase Opportunities on the Thu/Fri but it is not as good as I had hoped with a nice Set-Up and Dryline etc.

But the one thing on our Side is 6 days for this to change, remember it is just a Computer Model interpreting how the Trough will come out, The SPC Seem to have disregarded the GFS Scenario of barrolling out the Trough to Clear the Great Lakes in 3 days with the ECMWF Solution of Holding up the Trough out West and throwing a Short Wave across the Plains.

Should get a better handle on this by SUN/MON When it comes into the 4 days range.

Paul S

[Harry]

LOL

I must admit when I read Paul's post the pessimist raised its ugly head and I thought "oh no, 3 days gone"

[John Hanrahan]

Just need to clear up my post a bit after being lambasted by Mr Hanrahan on the Phone FOR Sounding Negative

Yes the language filters on the forum would not let me articulate what I needed to say to you via PM. Sorweeee

[Nick F]

I'm sure there'll be some play next week and you'll see some supercells. Though looking at the usually more reliable ECM I would like to see the trough moving in from the west amplifying alot more and digging further south across the Mountain West later next week than is currently shown, upper flow around the trough moving east next week looks a lot flatter than currently with strongest flow over Nern/central Plains. Still, time for changes before then

[Paul Sherman]

I certainly wouldn't think it's scuppered anything yet! The synoptic set-up is favourable for severe weather (large upper trough to the west - southerly low-level flow ahead of it). I wouldn't get worried about EC's lack of moisture on yesterday's run, especially as today's is much more favourable!!

Just Copied the above from a Conversation with Paul Knightley over on Ukww - He has Access to the ECMWF Charts we cant see as he works for a Meteorology Group. And SPC 4-8 Day Outlook is from yesterdays ECMWF

The Last Line is the most Important!

Paul S

Edit: If it stays as it is we could be burning some petrol Tues Night and Wednesday to get around 800 Miles North towards N Kansas and Nebraska

Norman for the 1st Night