Author Topic: April 30 to May 8, 2007 - Including the Greensburg Kansas EF5 Tornado  (Read 73182 times)

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Offline Jimmy Deguara

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Hi,

It looks reasonably exciting to see some prospect chase days here in Tornado Alley. Moisture should not be a problem with ample moisture in the gulf as well as some fairly recent and regular rains in Texas this year and especially over the past couple of weeks.

Although there is action from 30th April through to 1st May 2007, the next trough looks to be a little more interesting for more clean action over SW Texas with good lower level turning. the guys will be here by then and we will be in a position to head out proper.

Macca and Chris are out in force after yesterday's action with a nice shelf cloud in southwest Texas. We'll see how they go today with some potentially good action if things can align well. The atmosphere is still messy after last night's and this morning's convection but we'll see how it evolves. the models do suggest that far SW Texas will be clear so I think that region can get something firing off from Mexico and crossing the border. Typical HP supercell variety. I am a little concerned with the upper level shear being too weak and especially in this region may become stagnated.

Regards,

Jimmy Deguara
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Offline Jimmy Deguara

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Hi,

A tornado watch has been issued for the target region given there is an outflow boundary. Also there is an existing storm most likely a supercell well to the NW in Mexico almost running parallel to the US/Mexico border. Any supercell the crosses the boundary can also become tornadic along this boundary or in Mexico for that matter.

We'll see how Macca and Chris go given they were targetting this region.

Regards,

Jimmy Deguara
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Offline Jimmy Deguara

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If Macca headed down where they said in our discussion this morning, they are on a tornado warned beast with hook echo! Very nice on NWS radar.

Hail too the size of tennis balls was reported from the storm 7pm CDT.

Regards,

Jimmy Deguara
« Last Edit: 02 May 2007, 04:57:05 AM by Jimmy Deguara »
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Offline Jimmy Deguara

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The western storm merger did wind up producing a tornado:

A TORNADO WAS REPORTED. THIS TORNADO WAS LOCATED NEAR BRUNI from the National Weather Service warning statement. Radar indicating large destructive hail.

Regards,

Jimmy Deguara
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Offline Macca

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Hey Jimmy,

Yep - we did head down here to far southern Texas and had a run in with a near-stationary HP supercell.  See below for the report.

We started the day in Big Spring (a bit late due to my late night last night and a small sleep in this morning).  A quick data check saw us heading S to try and get in front of the outflow boundary from the previous night’s convection.  It was aligned east west and was heading slowly southwards from about San Antonio to Del Rio.   

It was totally cloudy for the majority of the drive and we almost gave up but a our spirits were lifted when SPC issued a tornado watch box slightly further N than we’d previously though and then a freak wireless internet connection in Leakey allowed us to see the outflow boundary and the potential for some serious storms if they could utilize the boundary.  Low level flow was impressive to say the least with 850mb winds from the SE at 30-35knts.  Mid level flow was relatively weak with 30knts at 500mb from the W.  Overall, shear was easily enough for supercells but a little more speed shear would’ve been nice…hehe. 

A cluster of strong storms was riding the boundary in the eastern parts of the T-watch box quite a way off to our S but we knew this was really our only hope.  We wanted to get to Freer as this gave us some better road options so we hoofed it down I-35 and then east on SR-44 towards Freer.  Unfortunately (yet somehow this wasn’t something you could complain about), the storm turned hard right and went from moving in an ENE’ly direction to going SE and then almost due S!  It was training along the boundary and moving very very slowly (10-15mi/h).  It sat over Freer for over an hour with large hail reports (up to tennis balls) was reported from parts of Freer for 1 hour and 5 minutes. 

We stopped to watch the base from the WNW side but it soon was hidden by the RFD.  We tried to punch through the cell (not the RFD so much but moreso the edge of the core) in an effort to get to a SW’ward road option but encountered strong winds, driving rain and some large hail.  The hail started off relatively small (1-2cm) and it wasn’t until we got within 5mi of Freer that it got large.  A few LOUD donks on the car indicated the hail was getting bigger and then we saw some larger stones bouncing on the road.  We estimate these to be about 4-5cm but we saw nothing larger than that and these were quite sporadic.  We did get a blasting of hail in the 2-3cm range which was deafening on the car and we realized that we couldn’t keep going this way so we had to turn back.  It was 40mi back to I-35 (our only south road option other than going further into the hail).  We cut our losses and started heading back to I-35 and the storm kept building westwards along the boundary and moving basically due S.  We headed to Laredo with a few stops for photos of the structure on the way and then as the sun went down, we headed about 5mi east of Laredo to get some lightning pics as the storm moved off to the SE.  While we were there, another storm developed rapidly on the outflow boundary right over Laredo and we were alerted to it only when it put out a flash of lightning.  No more than 5 minutes later, it was dropping CG’s only 2mi away – this made for an AWESOME sight with the precip being lit up by the setting sun and the blue CG’s streaking through it.  They weren’t frequent but they were very nice.  Eventually we retreated to the car and the cell weakened somewhat (but not before radar indicated it had up to 5cm hail – not bad for a storm that was about 30mins old).  We headed back into Laredo and noted some minor road flooding from the storm.  We have stopped here for the night to gather ourselves after a somewhat up and down day.  We discovered this evening that one of our headlights got smashed (most likely by hail) however the car suffered no other damage. 

Tomorrow looks relatively similar to today.  Strong instability (LI’s of -8 to -9 and CAPE of 3000 j/kg) with moderate low level winds of 20-25knts at 850mb and only moderate mid level flow of  30-40knts at 500mb.  Again storms will probably be most severe in the vicinity of outflow boundaries and it will be a matter of trying to find one of those tomorrow.  Our plan is to head N along I-35 – moreso to get back into a reasonably central position but also into the area where the most favourable mix of instability and shear occur.  It also looks like this southern area may be a little “tapped” from today so might not have as much potential tomorrow. 

Will try and post an update in the morning.  This has certainly been quite a hectic start to this trip with 2000mi covered in just 4 days.  2 very impressive storm days to start with.  Chris mentioned yesterday that in comparison to our last trip here in 2005, we got our first storm 6 days earlier than last time so hopefully if this trend continues, we should do ok this year.

Link to some pics from today are here… 

http://macca.bsch.au.com/gallery/20070430

Thanks for the thoughts on the reports peeps…keep them coming…

Macca & Chris

Offline Macca

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Hi all,

In Laredo this morning just doing some washing and taking care of business ;)

Today is looking relatively similar to yesterday although with slightly less upper level support (which is offset by slightly more juice in the lower levels).  LI's are progged to be around -7 to -8 and CAPE is forecast to get into the 3000's across south central Texas.  Overnight (and morning) storms have left a couple of outflow boundaries - both aligned relatively east-west.  One is sitting from about Austin to Junction and another sitting a little further NW from Abeline to around Midland.  Instability is relatively indifferent across these two boundaries (which should be the focus of convection this afternoon) but there are some differences in shear.  Surface winds look to be from the SE at about 15-20knts across both regions, however, the Austin - Junction OFB should see 850mb winds of 25-30knts from the SSW with a moderate low level jet (LLJ) currently running along the I-35 corridor from San Antonio to Dallas.  The Abeline OFB has more slack 850mb winds (and 500mb winds too) so we'll probably focus on the Austin boundary.  500mb winds across the boundary look to be in the 30-40knt vicinity so not overly strong but its about the same as yesterday and with the strong instability, a few supercells shouldn't be too hard to find.  We have some things to take care of in San Antonio this morning but after that, we'll head up I-35 to Austin (or near to there) and see how this afternoon shapes up.

Tomorrow is looking potentially potent as a vigorous shortwave upper trough moves into western Texas.  Not only does the mid level flow increase to 40-50knts from the west and the low levels maintain their 20-30knt SE'ly trend, the instability increases even moreso than today as the upper trough starts to have an influence.  The   latest GFS run shows LI's of -11 to -12 and CAPE in excess of 4000j/kg.  It could be quite a day tomorrow if this comes off.  There are a few differences in the models as to the timing of the upper trough but I wouldn't be suprised to see a moderate risk upgrade for tomorrow.

Will keep you all posted as to our happenings today. 

(Long term model runs do not look like giving us a break for at least 6 more days...hehe).

Macca & Chris

Offline Jimmy Deguara

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1st May 2007

Target region seems to be near Austin to Waco though I would not be surprised if initiation occurs in the baked up region near San Angelo. In discussion with Macca, I do believe that storms will require to drift S in order to maintain some clean inflow. Shear is moderate and instability is high - near 3500 - pretty nice for early May.

2nd May shows slightly in different shear though high CAPEs. I would not be surprised seeing over the 5000 CAPE mark on this day so it can help provide a focus for some explosive development if the strong cap holds things down. Watch out west Texas.

Regards,

Jimmy Deguara
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Offline Michael Bath

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Interesting right mover south of Brownwood Texas after 5pm. Wonder if any of the tourists are on to it !





EDIT: is it a right mover ?  Almost stationary with backbuilding
« Last Edit: 03 May 2007, 03:23:59 AM by Michael Bath »
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Offline Macca

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Yep - we were on it.  No tornadoes (only 1 reported early in its life), no hail (reports of 4.25 inch hail about 3 miles from where we were) but some fairly nice structure.  Report and pics to come soon (slightly distracted by the lightning outside atm).

Macca & Chris

Offline Macca

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Hi all,

Ok so we took care of some business in San Antonio early this afternoon after doing some washing at our hotel in Laredo.  After having to change cars (due to previous day’s damage), we set up the laptop again to see the first cell of the day go up along the Austin boundary (which had drifted N from where it was in the morning).  The cell exploded rapidly and was tornado warned with a confirmed tornado after just 90 minutes.  Unfortunately it was still quite a ways off to our NW.  So we blasted N along US 281 to Round Mountain before heading NW to Llano along SR71 and then W along SR29 to the intersection of CR405.  We made our first stop just past CR405 where we watched as the storm put down a nice wet RFD to our N and the wall cloud wrapped up very nicely.  Mid and low level inflow bands were present and the structure was quite nice.  (We later found out that this RFD to our N produced 4.25 inch hail not too far from where we were!!). 

After watching this for a short while, it got a little close so we headed back to CR405 where we headed south about 1mi to Castell where we stopped again for more photos.  The inflow band had become quite large and the wall cloud had wrapped up very nicely.  We were sitting quite close to the vault region downwind of the main updraft and we were cautious of hail after yesterday.  The rotation at this point was very impressive, however, the lack of low level winds probably prevented this cell from dropping more than just one tornado.  The storm was quite a way further west than we’d hoped things would develop and as such, the better low level shear was off to the east, however, the only action out to the east was linear.  After a while, and then tried to go further S along CR105 (an extension S’wards of CR405) but it turned to dirt about 200m along the road.  A quick U-turn saw us make it back to Castell just as the rain started.  Again we were worried about hail but we managed to escape along FM152 to the east back up to Llano through the less intense part of the storm.  We lost a bit of ground on the storm here due to the storm cutting off a few more ideal road options but we scooted southwards to Fredricksburg and then NW along US87 for about 8 miles where we again intercepted the storm as it wrapped up in spectacular fashion.  Inflow striations wrapped around the updraft, a low level inflow band extended off to the east and the guster marking the front of the RFD was wrapping around towards us from the W.  We were basically looking into the notch which is the only place you can be on a HP to see anything.  We didn’t see anything…hehe.  This was the last gasp for this cell as it become more outflow dominated.  We dropped back into Fredricksburg so as to avoid another hail pummeling and then dropped SW where we stopped and watched as the storm pushed out towards us (in a very much outflow dominated manner).  We then dropped down to Kerrville where we have shacked up for the night.  The storm moved over here a while ago and gave some really heavy rain and some awesome lightning.  I managed to get a few CG’s on the digicam – one was quite impressive but I was disappointed I didn’t get the other half of this CG which hit a radio tower about 100m from here (behind me)…the instantaneous crack of thunder that followed nearly required a change of underwear for me. 

The storm is still flashing away off to the S and SW (and W) but its into the anvil crawler phase now and they are too distant for photography. 

I’ll post more on tomorrow’s set up either later tonight (its nearly midnight) or tomorrow morning.

Link to today’s pics are here…

http://macca.bsch.au.com/gallery/20070501

Macca & Chris

Offline Jimmy Deguara

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Hi Macca,

Awesome structure - pity it could not hold down longer so we could arrive there from DFW airport. We left 3:30pm so we arrived 8pm ish  given it slowed down and then back built. I guess my target initiation was in that region well San Angelo region.

So I see base ball hail warnings yesterday on that storm and then this morning more base ball hail warnings. Wow!

We are in Junction, Texas - Macca and Chris were at Kerrville not far away at all. Awaiting for things to begn firing across the border or in Texas NW of here. An existing complex that produced the very large hail is moving SE hopefully it does not ruin the day.

Regards,

Jimmy Deguara
« Last Edit: 03 May 2007, 09:35:24 PM by Jimmy Deguara »
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Offline Macca

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Hey Jimmy,

Yeah - there was one report of softball hail from yesterday from fairly close to where we were. 

Today is an interesting one.  A vigorous short wave upper trough is moving across southern New Mexico and into western Texas.  Ahead of this, a very moist airmass is in place.  We are in Kerrville at the moment.  Its 12:30pm and its drizzling and has been all morning.  A dryline has set up across far NE'rn Mexico with DP's in the low 70's ahead of it and in the high 40's behind it.  Very well defined.  There is a bulge in this dryline which is fairly close to Del Rio.  There is also an outflow boundary which is pushing quite quickly SE which could interact with the dry line in about 2 hours right near Del Rio!  This will probably become our target to start the day as storms should develop where these two boundaries intersect in the next 2-3 hours and move eastwards towards Texas.  500mb temps are quite cold (-15C) and with surface temps possibly getting into the mid 80s' combining with low 70's DPs, CAPE values should exceed 3500j/kg.  This bodes well for some very very large hail.  Shear is adequate for strong supercells as well and if storms can make it across into Texas, a moderate southerly LLJ of 20-30knts is waiting to feed these storms.  Mid and upper level jets are entering the south central Texas region this afternoon with 500mb winds forecast to increase to 40-50knts from the west and the upper level jet is forecast to increase to 80-90knts.  There is some nice divergence aloft too just incase there wasn't enough lift already. 

SPC just issued an updated convective outlook for today and have a 5% chance of tornadoes and 30% hatched area for hail (meaning 30% chance of hail greater than 2 inches within 25 miles of any given point in the area).  They mention that they considered upgrading to moderate risk but a few uncertainties have kept it to a slight risk only.  CAPE values are currently around 5000jkg over Mexico where the cloud has cleared.

Things may go a little linear later today but hopefully some nice supercells will develop before that happens  :) .

Macca & Chris

Offline Michael Bath

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Quite a strong meso showing on the base reflectivity and base velocity scans from Laughlin Air Force Base Texas Radar @ 1.23z (8.23pm CDT)




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Offline Macca

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Hi all,

Today had the potential to go crazy and it did.  But not for us.  We made a decision during the early afternoon to head S from Kerrville to Uvalde.  At the time, we figured the OFB and the dryline would intersect pretty close to Del Rio.  CAPE was also much higher further S and the cap was somewhat stronger so we figured storms would remain discrete for longer.  All of this happened…a massive storm blew up about 40mi over the border into Mexico.  We saw this on radar from Uvalde and we figured that with the 40knt mid level jet from the west and relatively weak low level flow over in Mexico, that this storm would move in a generally eastward direction and cross over into Texas somewhere around Eagle Pass (which was hit by a tornado only just over a week ago).  But…the storm took a HARD right turn and moved SSE with a massive hook echo showing up on radar.  The storm basically paralleled the Texas/Mexico border for hours with the storm sitting about 25-30mi over into Mexico.   We tried to go S to intercept it if it was eventually to cross the border but we rain into dirt roads so we basically had to give up on this storm.  What made things worse was that many of the places we had driven through earlier today were subsequently hit by some very nice supercells (Kerrville, Uvalde).  I’m guessing that the OFB stalled across the southern Hill Country and supercells just developed along this as the airmass destabilized late in the afternoon (it was still 8/8 and drizzling at 4pm in Uvalde).   We eventually got some minor redemption finally getting onto the tornado-warned storm near Frio about half an hour after sunset.  We managed to get into a decent position which allowed us to look into the notch of this HP supercell which was relatively frequently lit up by lightning – we didn’t see anything.  We also met another chaser who had also gone for the Mexican stuff (making us feel not quite so bad).  We were treated to a pretty nice lightning display (which is still going as I type this as we are driving N along I-35 – its 11:35pm). 

In hindsight, our forecast was pretty spot on.  The most isolated storm/s developed further S (ie away from the MCS) and were probably the most impressive in terms of radar echoes.  The “target” cell developed just ahead of the dryline/OFB intersection and remained discrete for its entire life pretty much (its still going!).  The HUGE problem was that it was in Mexico and we weren’t (not a visa/passport issue – but again the rental car issue).  I’m still quite surprised at how hard this storm turned to the right – I would’ve thought this would be more likely on a day like yesterday with weaker mid-level flow.  Overall a fairly frustrating day but if the only reason for a semi-bust is an international border, then things can’t be too bad ;).

We are making tomorrow a driving day.  We are going to boot N along I-35 as far as we can as Friday onwards looks very nice.  A strong cap looks to be in place S of about I-70 so we’ll try and head for say Wichita, KS tomorrow (about 550mi) with the thought of wanting to be in the vicinity of Hayes, KS by cap breaking time on Friday. 

Macca & Chris

Offline Macca

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Day 7

Although all reports may not yet be in, SPC is showing that no tornadoes were reported from the storms over south western Texas yesterday (not sure about the Mexican storm yet although it is highly likely that it was tornadic).  So even though we missed a lot of the action and probably some great structure in Texas, we didn’t miss out on tornadoes. 

Today was a designated driving day to get into a good position for tomorrow (more on that below).  We left San Marcos (between San Antonio and Austin, Texas) at about 10am and basically drove all day and we have stopped for the night in Wichita, Kansas (yep – we drove through a lot of Texas and ALL of Oklahoma today – about 580mi (925km). 

Just a little bit of info on today…the “action area” of the upper trough from yesterday was still hanging around eastern Texas into Louisiana and Arkansas and the centre of the weakening upper level circulation was sitting over central Oklahoma and moving eastwards.  A considerably moist boundary layer was present over the eastern half of Texas and there was still some reasonable (but weakening) shear.  LI’s were around -7 to -8 over south eastern Texas and getting up to about -4 to -5 over north eastern Texas so there was still quite a bit of instability around.  A few isolated storms (possibly short-lived supercells) developed near DFW late this afternoon but we had already left by that stage.  Two or three more lines of storms developed over far eastern Texas, Louisiana and Arkansas and these had plenty of storm warnings on them but that area isn’t the greatest to chase and it was very linear.   We basically decided to make today a “relaxing driving day” as opposed to a full on chase day followed by a 6 hour drive after chasing and then another 6-8 hour drive tomorrow to the target area.  From what we saw on radar today, this probably was a decent move as I don’t think we missed out on too much over Texas. 

We did run into a line of storms which formed along some sort of boundary near Oklahoma City.  Hail of up to 4cm was reported from these storms quite close to where we were but these storms were relatively high based.  Given that they were located near the centre of the cold pool, the updrafts were quite crisp.  We also got a fairly AWESOME sunset here in Wichita tonight.  It was nice to have a “day off” today (even though we saw plenty of storms on the drive N).  We have plenty of time to watch things begin to evolve for tomorrow. 

Ok – now for tomorrow.  The first thing to note is a significant upper level trough digging into the central high plains tonight and tomorrow.  This upper level feature is forecast to stall over the high plains for the next 4 days (Fri – Mon) with GFS finally pushing it eastwards by day 5 (to the eastern parts of the plains states) and then into the Mississippi River valley area on Day 6 in a weaker state.  This finally sees a ridge push into the plains, giving us some time to recover from this somewhat hectic but at the same time very welcome start to our trip.  If this upper level scenario comes off, we will have had significant chase days on 9 of the first 10 possible chase days. 

So…this upper level trough – the timing of its arrival tomorrow and its impact on surface features is still in question with GFS and NAM varying somewhat as to the outcome for tomorrow’s convection.  It is currently having an effect on NE’rn Colorado and eastern Wyoming where storms developed along the front range today.  This evening, a well mixed boundary layer sees dew points in the low 60’s (16-17C) across all of eastern Oklahoma and Kansas with a warm front currently moving slowly northwards through central Kansas.  Higher DP’s (65-70f’s) are present over central Texas at the moment.  Both GFS and NAM are showing slight increases in moisture levels tomorrow so that DP’s should be around the mid 60’s (18-19C) by prime time. 

With the approaching upper trough, a dryline is progged to set up across south western Nebraska extending down through western Kansas, western Oklahoma and into west north central Texas.  Significant pressure and temperature gradients between the upper level trough and the developing upper level ridge over the great lakes/missisippi river vally region is set to cause some very nice shear late tomorrow (and even more insane on Saturday).  Sharpening of the dryline in response to the approaching upper trough is going to result in a low level jet (LLJ) of 30-35knts (at 850mb) from the SE.  This is being overlayed by strongly diverging winds at 700 and 500mb’s and also in the jet stream (lets say 250mb).  700mb winds are SSW’ly at 40knts, 500mb winds are SW’ly at 45knts at 250mb winds are SW”ly at 70ktns.  Instability is not an issue with CAPE’s extending from 2000j/kg over south western Nebraska up to 4500j/kg over Texas and LI’s of -4 to -7. 

So, we have shear, we have instability…what is left in our equation?  Trigger.  We have one of those too…the convergence on the dry line.  So we should have some freaking awesome storms right?  Well…yes…BUT…there are two other things we need to consider.  These two things are where GFS and NAM have some interesting differences (interesting given we are only 24hrs out).   The two things we need to look at (which are linked) are the cap and focus points for convective initiation given the varying strength of the cap along various parts of the dryline.  GFS has some very warm 850mb temps sitting over the dryline from Texas up into central Kansas.  850mb temps of 24C extend all the way up to northern Kansas (lets say Hays) but north of there, the cap weakens to 21C and then 18C in quite a short distance.  A quick look at surface RH (basically the DP), GFS has a dryline bulge right near Hays.  A bulge in the dryline is often the focus of convection and frequently results in any supercells becoming tornadic.  The reason for the focus of convection is that it acts as a convergence zone for moisture and as a result is often the place where a strong cap can be broken.  The reason for supercells becoming tornadic is that the bulge in the dryline causes the surface winds to curve around into the corner created by the bulge, giving the low level flow a more easterly component and increasing the SRH in the vicinity of any storms that develop in this area.  (Feel free to correct me if this is not totally right or if there is a better way to describe this).  So GFS has the bulge sitting up on or just north of I-70 (which runs E-W across Kansas about 2/3rds of the way up).  The place to be in this situation would be to sit just NE of the dryline bulge and wait for convection to develop.  It is not uncommon for supercells to fire south of the dryline bulge too if the cap can be broken and when this does happen, these supercells tend to be very isolated and photogenic.  If the GFS scenario comes off, I have significant doubts as to whether any convection will initiate south of the bulge with the very warm 850mb temperatures (ie 24C+).  Some chasers are convinced that the significant lift associated with the approaching upper trough will be enough to break the cap but I made a rule when I was here last time (after 3 clear sky busts) that I wouldn’t chase an area which had 850mb temps of >20C.  Tomorrow will be no different.  The NAM scenario is similar to the extent that it also has a dryline bulge however, it situates it about 60-70mi further S near Great Bend, Kansas (almost right in the middle of Kansas).  This results in the main area of convergence being in a higher moisture area and thus instability is quite a bit higher (2000-2500j/kg with GFS compared to 3500-4000j/kg with NAM).  The main difference arises with the 850mb temperatures extending S of the dryline being in the 20-22C range.  This is more likely to be breakable than the GFS scenario.  If this was to come off, a few isolated very strong supercells would probably develop S of the bulge in southern Kansas into central western Oklahoma. 

Given the combination of shear and instability tomorrow, I think we can expect to see some very strong supercells develop with tornadoes quite likely with any supercells which form (whether in the bulge or S of there).  Very large hail is also likely (3-4 inches/6-10cm) as are damaging winds.  SPC has currently only gone for a slight risk due to the uncertainty regarding the cap strength (and thus how widespread storms will be tomorrow), however, I think we will see an upgrade to a moderate risk at least for central/north central Kansas and probably southern Nebraska for tomorrow, possibly extending quite a way to the east (moreso N of I-70).  Convection should evolve into an MSC in the late evening as the LLJ (850mb winds) strengthens futher to 50-60ktns.  This should move eastwards across northern Kansas and southern Nebraska overnight tomorrow and through Saturday morning.  The likely development of this MSC and the potential for this to have severe weather all night across the border regions of Kansas and Nebraska should only strengthen the case for a moderate risk to be issued for tomorrow. 

At the moment, there is really no way of telling which of the two scenarios is going to be in place by prime time tomorrow afternoon, however, either way, we will most likely be playing the dryline bulge (about 95% sure).    This is going to be the best chance of getting convection to initiate before dark and also the best chance of tornadoes (there is a decent chance the dryline could fire further S after dark as the lower levels cool and the cap weakens…this could be nasty if this happens given the strengthening LLJ…).

We will check data tomorrow morning (we have to check out of here by about 10-11am) and it should be clearer by then where exactly this bulge is going to be.  Every chaser and his/her dog will be out an about tomorrow and Saturday as this is looking to be one of the best set ups for the year so far.  We are expecting significant chaser convergence in the vicinity of the dryline bulge tomorrow although the chance of more isolated convection further S along the dryline will draw some chasers away from the crowds.  We should have time to post an update tomorrow morning. 

For now…we just sit and wait. 

Macca & Chris