11/5/08 FCST: IA/MO/AR/E. KS

[Scott Weberpal]

Current GFS indicates a potential chase day next Wednesday, especially in MO through S. IA. A deep, vigorous trof is progged to eject out of the four corners region into the upper midwest with an attendant deep surface low. Moisture will be a major question mark (when isn't it this time of year?), but cold temps aloft should help offset the moisture issue.

At this point, southwest to southcentral Iowa into W. MO appears to be the favored region, but I'm sure the models will have major mood swings before next Wednesday arrives.

Something to keep an eye on.

EDIT: I completely overlooked the E. NE/SE SD cold-core potential during my original post. Low 50 Td's forecast juxtaposed with -20 to -25 H5 temps, and in the immediate vicinity of the deep sfc low. I may actually favor this area over the typical warm sector play if it pans out.

[Mike Hollingshead]

I think of two days when looking at this one. November 12, 2005... not so great moisture....time of year....mid-level low to some degree, and location of things. That day the sfc low also played out with tors. I think the mid-levels were a bit less backed than the gfs prog's at the moment. But it is something to watch.

The day I could see it turning out more like is the day Van Dewald got that dusty tor in nw IA. I can't remember the date, but I know you chased it too Scott. Surface low position is rather close to both those days if I recall.

Hopefully the ECMWF will slow down from where the 0z run had things, as it's over by the 5th. Unless you like sw WI, lol. If dews could be there by the 4th I'd even take a two day'r.....but getting them worth much by the 5th might be a challenge. Heck a slower mix with the ECMWF would be great, slow it down, but be more open than the GFS shows the low.

[Chad Cowan]

SPC is really bullish with the new 4-8 day outlook. The kinematics are definitely in place, but am I the only one that doesn't see enough moisture there for an "outbreak"?

[Brandon Ivey]

Wednesday does look like a potential cold core event looking at the latest GFS run. Right now it looks like SE Nebraska and Eastern Kansas would be the best location to chase in. I-80 down to I-70. The target location is sure to change with future runs, but this system does look interesting. Going back to standard time tonight does not help. It will make that 2-3 hour window of opportunity occur an earlier in the day. Not good for those of us working. I would expect the 2pm-5pm timeframe to become active if this scenario plays out and I will be taking off early from work if it does! :D

[Michael O'Keeffe]

I noticed that as well, but the 12z GFS looks a lot different. The GFS is justing killing me showing a cold core setup in Nebraska one moment the next it looks like a weak warm sector event. I will likely wait for the ETA tomorrow before really start forecasting for this setup because who knows what's going to happen.

However it really could be interesting if we could get some cold core or even some decent CAPE in the warm sector.

As of the 12z GFS I'd look to SW Missouri as it always seems to perform well in these types of setups. Jan 7?

[Mike Hollingshead]

Apparently the 12z runs are the "crap runs" and 0z runs are the "nice" ones....on the GFS. Night it looks good, morning it looks bad. If you want to see where the NAM is, just compare it with last night's 96hr 500mb run on the GFS and its/NAM's 12z 84hr 500mb run. The current 84hr run of this morning's NAM much more closely matches how the GFS was handling it last night....so that is a good sign. And heck even the 12z GFS I could see some hope in IA and a likely chase day for sure.

[Scott Weberpal]

SPC is really bullish with the new 4-8 day outlook. The kinematics are definitely in place, but am I the only one that doesn't see enough moisture there for an "outbreak"?

It wont take a ton of moisture for a good coldcore event. Even low 50 Td's will be ample under such cold temps aloft. Tornadoes in the warm sector may be more difficult to come by north of the KS/OK border into AR.

[Mike Hollingshead]

As for moisture and November, this might be of some use. Thanks for the link Dick.

http://w1.spc.woc.noaa.gov/exper/ma_archive/

Put in November 12, 2005. T/TD/Wind 23z and Past 6 hours. Then look at central IA where big tornadoes occurred late afternoon.

[Andrew Stoller]

This system though doesn't look to have nearly the kinematic wind field of the Iowa set up 3 years ago. Look at how backed the surface winds were then compared to how they are projected for this setup. This setup looks quite cold front/squall linish as of now. Although with 5 days out, the system might not even be there by Wed!

[Dustin Wilcox]

I have about as much faith in this being a legit chase day as I do the Huskers upsetting the Sooners tonight. 12Z was a sour trend, and that was followed up by the always trusty 18Z which looks just as poor. I'm putting on my rally hat and hoping the thing slows down and that sfc low doesn't kick out so quick, if anything sub 997 is sitting over NE/IA area backing the winds under that upper level energy, I'll be happy. I'd have a hard time drawing up a better week than the skers upsetting the sooners, followed up by a November tornado; though currently both scenarios seem quite unlikely...

[Scott Weberpal]

This system though doesn't look to have nearly the kinematic wind field of the Iowa set up 3 years ago. Look at how backed the surface winds were then compared to how they are projected for this setup. This setup looks quite cold front/squall linish as of now. Although with 5 days out, the system might not even be there by Wed!

Last nights run had the sfc winds significantly more backed as did the run the night before. As mentioned, the 12z runs have looked terrible while the 00z runs have looked great. If last nights run comes to fruition, it should be a significant event; if it ends up more like this mornings run, expect a washout.

[Andrew Stoller]

Last nights run had the sfc winds significantly more backed as did the run the night before. As mentioned, the 12z runs have looked terrible while the 00z runs have looked great. If last nights run comes to fruition, it should be a significant event; if it ends up more like this mornings run, expect a washout.

Ahhhhhhhh, makes sense. I hadn't even looked at models or the SPC for the last 3 weeks until this afternoon.

[Scott Weberpal]

Yeah, they've been bouncing around. 2 nights ago it had a 984mb low centered over Sioux Falls with ape**** kinematics to boot. Obviously this mornings run leaves a lot to be desired. I'm placing low confidence in all the GFS runs at this point, and may have to wait until Tuesday night to make a final decision. Good news is I can easily get out of class/work Wednesday and if need be reschedule my Thurs. morning exam. It would be nice to get out one more time this season, but I'm not holding my breath at this point.

Good news is there will be convection, bad news is cold air for Wisconsin after the low passes.

[Scott Weberpal]

Of course the 00z GFS looks good again. Backed SFC flow east of the low and a nice broad warm sector covering most of Iowa. Coldcore looks good in NE, but I'd rather play Iowa if it appears the warm sector will pan out.

I guess I'm in wait-and-see mode now. No point in picking apart each and every GFS run when I probably won't make a decision until Tuesday night anyway.

[Michael O'Keeffe]

Wow I agree the GFS does look good on tonight's 00z! The 6z WRF and GFS this morning though both continue to look good which means maybe the 12z GFS may continue to look good as it is showing 60F dews all the way to the KC metro area! The 6z WRF only shows to 18z Wed, but has 1000+j/kg of cape over C KS by that time as it shows dews projected to be in the 60s at that time all the way north to the KS/NE border and a broad area stretching from C KS into W MO. This setup is really starting to become a nice looking event. Now the question is, do you chase the cold core, or do you chase the dryline?

[Mike Hollingshead]

I'm getting the feeling there isn't going to be any cold core setup with this system, though yeah, lots of time yet for it to lock onto something with one.

Interesting seeing the 0z runs of the ECMWF now as well as Canada's GEM model. Both have a hell of a big trough with similar nice shear over a large region.

Now the 12z NAM is in and it is quite similar to those two. Hopefully it can stay as little 'cold-fronty' as possible. It's a bit of a banana low on there now. That and keep the front from moving too quickly east, as the steering flow as it is should get storms off it once they fire.

Edit: 12z GFS definitely looks less cold fronty/banana low'ish.

http://www.rap.ucar.edu/weather/model/gfs078hr_sfc_mslp.gif

[Dustin Wilcox]

I would definetly like to see something like the 12Z gfs play out. The backing East of the sfc low has me liking the Yankton area (maybe just WNW) on this run, its interesting the GFS is progging >1000j/kg over a large portion of Central SD by 18Z just East and North of the sfc low along the NE stretching WF. Were the GFS to verify I would have some confidence in the possibility for a couple of decent storms just into SD stretching S into NE...

[Andrew Stoller]

The 12Z NAM even looks good for as far south as central KS along the dryline and it doesn't look too cold fronty at all. 1,000-1,500 J/kg CAPE, a few pockets of 60+ degree dewpoints, winds back slightly by 00z, aiding in decent helicity and directional shear. It's nice that the models are slowing the system down a bit which is making it look better/more dynamic.

[Michael O'Keeffe]

I'm with Andrew. I think area of real interest is SC KS from Hutchinson south towards KS/OK border. Very sharp dryline, some 60F tds, nice CAPE values and the shear is obviously there as well. I think there is potential for this setup to really do something nice especially from extreme S South Dakota all the way south into far N Oklahoma. So all in all if the 12z WRF verifies I likely head towards SC Kansas to play the classic dryline.

[Mike Hollingshead]

The 12Z NAM even looks good for as far south as central KS along the dryline and it doesn't look too cold fronty at all. 1,000-1,500 J/kg CAPE, a few pockets of 60+ degree dewpoints, winds back slightly by 00z, aiding in decent helicity and directional shear. It's nice that the models are slowing the system down a bit which is making it look better/more dynamic.

Maybe c KS south it doesn't. SD though NE into KS it does. Not show ender but a bit cold fronty, with wnw or nw winds behind the front. Through the day from 18z-0z you can see the sfc low elongating and weakening.

Everything looks great, it's just that tendancy/look that is of some concern. If it happens like that I could see a similar day to June 11, 2008. Messy line of embedded sups to the north. GFS just looks more promising over a big area. Even at that, 12z NAM still has a sure chase day.

[Brian Stertz]

Looks like the firing line will be along or slightly east of a Kearney NE to Russell KS to Alva OK to Altus OK line by Wed. afternoon (if the 00z ETA is to be believed). The dryline looks like it may be able focus supercells as the strong ascent moves northeast from W.Kansas. Shear looks like it will be decently strong and who knows on the instability forecast. Certainly could see the first supercells firing from C.Nebraska down into NC/C Kansas...with later development by evening south of I-70 down into NW Oklahoma. Looks like a good slight risk set up to me...but my opinions may change if more instability looks to align along the dryline a litle better. Tornadoes a possibility even on this latest ETA forecast.

[Mike Hollingshead]

Given a storm I would prefer the further south target in western Oklahoma.

JWG 0z via NAM (http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=072&STATIONID=kjwg)


CNK in nc KS ain't bad either (http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=072&STATIONID=kcnk)

If I had to guess now I'd wind up in nc KS....and quite possibly upset about not ending up in sc KS. Of course now the 0z GFS is the one leaning more cold fronty than the NAM. Pointless still at this point, but damn it's going to be hard to wait and not get excited over the next 4 runs.

What could be interesting if something like the GFS pans out would be possible snow with the same system in areas it produced the severe weather and any tornadoes if they happen.

[Connor McCrorey]

I have to agree that NW OK would be my favorite spot right now based off of the 0z NAM. Every time I have chased a setup with such great shear but such low instability I have busted completely. If a storm could really get going near Alva I could see some tornadoes late in the day, when instability is at it's greatest, but I just haven't had enough luck on my short time chasing with similar setups to get excited yet.

[Jason Boggs]

I think staying in an area to intercept north or south might be a good idea for Wednesday. In other words, don't commit too far one way or another. As of right now, and it will change, I like the area between Wichita, KS and Enid, OK. Say the area near Caldwell, KS which is a few miles NE of Wakita, OK. I think the better moisture and instability will be a bit better in that area. From the NAM perspective, it looks to bring Td of 60 or so east of the dryline along with CAPE of around 1500 and possibly higher. Obviously, daylight will be a problem this late in the season but I will sure keep my eye on things as the possible event gets closer.

http://img230.imageshack.us/img230/7008/analysismapyz5.png

[Andrea Griffa]

I think staying in an area to intercept north or south might be a good idea for Wednesday. In other words, don't commit too far one way or another. As of right now, and it will change, I like the area between Wichita, KS and Enid, OK. Say the area near Caldwell, KS which is a few miles NE of Wakita, OK. I think the better moisture and instability will be a bit better in that area. From the NAM perspective, it looks to bring Td of 60 or so east of the dryline along with CAPE of around 1500 and possibly higher. Obviously, daylight will be a problem this late in the season but I will sure keep my eye on things as the possible event gets closer.

http://img230.imageshack.us/img230/7008/analysismapyz5.png

GFS is forecasting less cape with values of 500-800J/Kg and convections starting by 00Z. I trust more Wrf model within 72 h and so far south central
Ks is a very good option. Moreover I wouldn't be surprised to see a tornado or two in Colby-Wakeeny zones.

[Rodney Price]

There's still some slight timing issues between the NAM and GFS. The NAM has the cold front aligned from northcentral through westcentral Kansas with the dryline east of there by 00Z THU. The 12Z GFS is much faster, with cold front overtaking the dryline right along the I-135 corridor by 00Z THU. If the GFS is right, the potent dynamics and lift, along with unidirectional flow just scream "linear". We'll see what happens.

[Chris Allington]

There's still some slight timing issues between the NAM and GFS. The NAM has the cold front aligned from northcentral through westcentral Kansas with the dryline east of there by 00Z THU. The 12Z GFS is much faster, with cold front overtaking the dryline right along the I-135 corridor by 00Z THU. If the GFS is right, the potent dynamics and lift, along with unidirectional flow just scream "linear". We'll see what happens.

I tend to agree with the NAM because all too often the GFS doesn't realize the depth of the low and seems to want to push things a bit too fast. Its done it a couple of times this season with the big upper lows over the rockies. If I could go Wednesday I'd be checking things over morning of and seeing how far I needed to get south into KS.

[Brian Stertz]

Looks like the firing line may be a little further east than I thought, and a maybe not get rocking until at/after sunset. I like the target showing up around Medford OK the best. Just far enough away from squall-linesville and very near a dryline/cf intersection. Not too much overbearing ascent and just the right convergence. After dark...it begins to look more interesting in the Wichita-Emporia KS area if the MesoEta is right. Shear gets pretty strong and could see some bows/lewps going on as the wind fields strengthen. Tomorrow could be a sneaky tornado day if things can cut loose by 4pm instead of 6-7pm. Agree with Jason's target 110%.

[Greg McLaughlin]

I just looked over current dewpoints and comparing them to model forecasts, and it appears the NAM is a little too bullish with dewpoints while the GFS looks to be more in line with current trends. I think the tornado potential is still up in the air for WED (talking about southern target OK/KS), but if the cold front doesn't overtake the dryline early on we might see a few photogenic LPs.....assuming the updrafts are strong enough to survive the shear.

[Michael O'Keeffe]

Well I wouldn't call this a bust yet. The moisture appears to be an issue right now, but we have 48 hours for the moisture to get up here and with low 60s in southern Texas already the very strong south winds we are expected to see tomorrow and wednesday I wouldn't be surprised to see at least low 60s over portions of the region (OK/KS). The GFS also shows the moisture over a higher region of the atmosphere from 0-30 km. While the NAM shows the lowest 0-2km which always tends to be a bit more moist. However if you look at the NAM's 0-30 km dewpoint map you will see it is nearly identical to the GFS except a bit further west and it isn't as cold front looking. Just a thought.

The main problem I see is initiation after dark, but a tornado is a tornado after dark or not. How many times can you chase with gas under $2.00? Not much in this day and age, so if there is a decent to good shot of some tornadoes, which appears likely I'd go for it. But that's just me.

[Greg McLaughlin]

Based on current models, I am not sure how one would be concerned with initiation after dark. The NAM and GFS both have precip broken out by 00z. Considering the placement of the mid/upper jets and pva I would assume convection would be going before dark. Now if we get supercells by late afternoon we might now get tornadoes until right after sunset....assuming there is even a risk of tornadoes.

Concerning moisture, I am a little pessimistic about moisture return considering current surface obs have some mid-upper 50s Tdps in the GOM. Its not like the GOM is loaded. Meager moisture will be a concern for the southern target, but not as much of a concern if you get a cold-core setup way up north.

[Scott Lincoln]

Based on current models, I am not sure how one would be concerned with initiation after dark. The NAM and GFS both have precip broken out by 00z.

Well it is November. Sunset is from 5:00pm-5:15pm now in eastern Kansas/Nebraska and Iowa/Missouri.

[Mike Smith]

Sunset in ICT on Wednesday = 5:27pm

[Robert Rohloff]

Well it might bust however gas is $1.80 and droping in OK, it is time to get out for a drive.....might get wildfire footage if all else fails. Heading west and north towards Ponca City and start out there.

Looks like a night event in this area at this point

[Greg McLaughlin]

Sunset is at 5:30pm and 00z is at 6pm. If the models are showing QPF by
00z then that likely means storms have fired at least an hour or two before dark. I think things get going sometime between 2-4pm. The latest runs of the NAM and GFS have precip breaking out by 1pm.

[Mike Hollingshead]

Cap starts going bye bye really early, at least according to the NAM. I wouldn't think darkness would be an issue either. I've thought that plenty of times before though and been very wrong, lol.

http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=045&STATIONID=ksln

Cap very gone at Salina by 21z/3pm. It's gone even before that to the west, and of course north.

http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=042&STATIONID=kear
Kearney at noon.

Enid and OKC gone by 3pm as well.

[Brandon Ivey]

The last two or three WRF runs have been pretty consistent on developing a target near the Kansas/Oklahoma border on Wednesday. It looks like this system won't really become a cold core low until it moves into the Midwest. GFS did pretty good though, about a day fast, as usual. I think the I-35 coridor from Wichita to Oklahoma City, currently looks good for Wednesday afternoon. The moisture gradient along the dryline will be the sharpest along the KS/OK border with dewpoints approaching 60 to be expected. The forecast soundings from KICT and KOUN look really good by Wednesday evening. 0-3km CAPE values are forecast to range from 63 at Norman to 176! at Wichita. 0-1km SRH should be around 300 with 0-6km shear of 50-55kts and overall CAPE values of 1,000-1,500. Everything is looking good for supercells to develop along the dryline with a few tornadoes possible. The cold front will help everything become linear during the evening as it overtakes the dryline.

[Andrew Ryan]

The 0z NAM still paints a better picture than the GFS. I agree with the target around the OK/KS border. The NAM progs CAPE values aoa 1500 at 21z and just about the same as what has been said before. I agree that moisture is still a problem. But dewpoints of 60F+ are slowly making there way north from the gulf. I don't think it's hard to imagine dews near 60 by Wednesday afternoon/evening. But as always, time will tell.

[Chad Cowan]

http://img87.imageshack.us/img87/6989/115otlkhp9.jpg

This is my preliminary target map, using the 03/12z model suite and 21z SREF as main guidance and refined with the 0z runs. Note that this map is my forecast for tornadoes only and not general severe weather which will extend well east into the night. The GFS has been unsurprisingly more progressive with the trough and subsequent sfc features. A quick glance at the ensemble members shows the Operational GFS as the progressive outlier (Black line), so this fcst will lean towards a blend of the slower NAM and Euro.
http://img265.imageshack.us/img265/1482/ensemblegfsmm6.jpg
I am not convinced the moisture return will be anything near what the 0z NAM is advertising, with 60 dews up into NE. In fact, I wouldn't be surprised to see the 60 degree isodrosotherm not make it into OK on Wednesday. The SW low level flow prior to the event will not favor deep, quality moisture return- but given a narrow tongue of mid-upper 50 dps, the seasonably cold temps aloft and unseasonably warm temps at the sfc, instability will be sufficient for supercells and tornadoes as far north as the sfc low in SD. Hodographs will enlarge throughout the afternoon as the LLJ backs and strengthens with time across the warm sector. This will be vital to the low-level turning in an otherwise unidirectional flow. I agree with Brian Stertz that we could see some LEWPs/embedded sups after everything goes linear.

I am favoring the southern target ATTM for a few reasons. First of all there is the potential for early-mid day convection in nrn-KS and NE as the strong forcing arrives a tad early. This could kill any instability, but the screaming storm motions up there would quickly take this convection away from the initiating boundary. Secondly there is the issue of the cold front and how much it will push east during daylight potentially mashing potential supercells into a congealed mess. Depending on which model to believe, the CF won't undercut the dryline until after dark in the southern target. Lastly, storm motions in the northern target under the 70+kt H5 jet streak will not be fun to chase. I miss spring.

[Michael O'Keeffe]

Wow moisture looks impressive now! Just checked the latest surface obs and dews are already in the mid-upper 50s across much of Oklahoma with low 60s right on their tail near the Red River. The moisture "problem" appears to be diminishing as winds are expected to increase through day across OK and KS.

[Paul Knightley]

A stout upper trough is forecast to dig in from the NW over the next 24-36 hours, inducing lee cyclongenesis and pulling Gulf moisture northward as a result. However, the moisture does not look too high, around 13-15C dewpoints, perhaps a 16C in N OK/S KS. A cold front/dryline intersection should form around about DDC by around 18Z, and then sharpen by 21Z/00Z, and being located (if you believe ECMWF) in a triangle bounded by DDC, GBD and P28. Storms would want to form close to and east of this, making the corridor from OKC to Salina a target area, although the more northern area would be overtaken with the cold front. However, further to the south, storms may not fire until close to or after dark, with a risk of some evening tornadoes for NE OK/SE & E KS. I think I'd be in Wichita for the morning, and then see what happens thereafter, with a tendancy towards Salina.

Whilst I think some probability exists for storms further east, I suspect it may be dark by then, so I'd hold to the west.

As always away from vacation time in May, this is all just practice on my part!

[Chad Cowan]

Wow moisture looks impressive now! Just checked the latest surface obs and dews are already in the mid-upper 50s across much of Oklahoma with low 60s right on their tail near the Red River. The moisture "problem" appears to be diminishing as winds are expected to increase through day across OK and KS.

I wouldn't be too quick to write off the moisture concerns for tomorrow, Mike. This is the initial northward moisture surge in response to the lee cyclogenesis that unfortunately gets 'pinched off' thanks to the anticyclonic flow over the southeast. Note the sub-50 dp sfc obs circled in red that will mix westward. This current moisture surge will be good for those targeting the northern Plains tomorrow.

04/16z sfc obs on left, 04/12z WRF 24hr dps on right

http://img208.imageshack.us/img208/7586/2008110416metarsabicn1.gif http://img407.imageshack.us/img407/3080/moisture1sp1.jpg

[Andrew Stoller]

Is anyone else worried that there is a lack of backing to the surface winds basically everywhere along the dryline? Looking at forecast skew Ts, it does seem to improve the further south you go. Ponca City looked the best from all the ones I looked at by 21Z. The winds also back more closer/east of the surface low, say by Wayne, NE by 00Z, but that far north, the 500 mb winds are more out of the south, so you basically get less degree of turning between surface and 500mb compared to the southern Target area. Lack of a backing component with the cold front really swooping in by 00z is my only concern; everything else looks great.

[Skip Talbot]

Forecasted effective SR helicity values over 300 in southern Kansas are more than enough to support discrete supercells and tornadoes. Thanks to the veering midlevel winds, we don't need completely backed surface winds for good directional sheer.

[Greg McLaughlin]

Right now I like the area between Wichita and Ponca City. I will be playing close attention tomorrow to any moisture tongue and try to be on the nose of it.

[Aaron Gerhardt]

Looks like I get to start my first post here perfectly, storm chase on my birthday week!

Looks like the forecasting models started with some cautious optimism, to some very favorable conditions. Tim Jones and I are teaming up and targeting the central Kansas area, but from the looks we're a bit all over the place as to where exactly we're going to see our best chances. I know moisture was an issue earlier, but looks like we're looking better every update. I looked at the SPC outlook and it looks a bit more cautious compared to last nights one, some early supercell development to squall out and then kick it into gear and outrun us. Hopefully we get out there early enough to track the storms as they fire, and not have to miss out on initial development

Need to be on the ball on this one, first abroad chase for me. Can't beat the gas prices even if it's a bit of a bust.

[JF Massicotte]

Well if I had the chance to chase, I'd start the day in Wichita and refine my target from here, sure looks good for supercells and shear seems supportive of tornadoes... Wish you all good luck!

[Angie Norris]

Things are looking interesting for tomorrow afternoon. Moisture looks to be tolerable with the WRF (or whatever it's name is this week ;)) showing Td's near 60 by 0Z, CAPE 1000-1500J/kg, nice speed shear, and a Theta-e nose in the mid 330's. Vertical velocities are persistant in showing something blowing up just SW and N of the OKC metro by 0Z, before things line out by 6Z. Storm motion will be NE at about 45kts. It will just be a matter of hoping an isolated storm or two fires before dark before the line forms.
Current target: Chickasha, OK.

[Chris Lott]

Ponca City doesn't look like too bad of a target tomorrow afternoon, with a little more instability showing up in that area. It also seems the cap should be gone as well allowing for a few sups to take off quickly. According to the models I believe a few cells fire between the 1-3 timeframe tomorrow afternoon before quickly racing off to the east and turning linear. I'm still questionable about the moisture that some of the models show to be in place over parts of Ok. As Angie said, some forecast soundings are showing almost 1500 j/kg CAPE in parts of OK. Shear shouldn't be a problem with this one.

[mikegeukes]

Reading some AFD,HWO, Springfield MO mentions low level shear pose a risk of a few embedded tornadoes. Kansas City, mentions a few spinups with bows, Topeka says, I cannot rule out a few weak tornadoes, Wichita if any storms discrete, brief transient tornadoes a remote possibility. Tulsa mentions possible tornadoes with supercells. Summary, if a few discrete cells can form along and ahead of the dry line, there is a possibilty of tornadoes. Cold front overtakes dry line, squall line with damaging winds, and hail.

Tornado Climatology for November 1950-2007. (58 years of Data)
Number of Years with tornadoes for the following states of: IA, KS, MO, NE, SD, OH
Iowa: 7 years, Kansas: 12 years, Missouri: 20 years, Nebraska: 3 years,
Oklahoma: 23 years and South Dakota: 0 years.

Number of Tornado Days for November 1950-2007 (58 years)
Iowa: 9 days Kansas: 15 days, Missouri: 25 days, Nebraska: 3 days,
Oklahoma: 39 days, South Dakota: 0 days

Mike
Your source for weather links
http://geukesweather.blogspot.com

[Andrew Stoller]

Looks to me like one would need to stay fairly far south (south of Wichita) to stay out of the cold front. Forecast soundings for Wichita don't look all that great for supercells, but much better further south. The 00Z WRF (NAM, whatever you're supposed to cal it...) barely has any precip broken out and everything pops after that (after dark!). As it stands, I'd target Ponca City, OK.

[Bill Schintler]

Chase target (south):
El Reno, OK (10 miles west of Oklahoma City).

Timing and storm mode (south):
Storms will fire along the dry line by 3 PM CST. Supercells and a few tornadoes will be likely early in storm evolution. The best target may be the “tail-end Charlie”.

Chase target (north):
20 miles east of Yankton, SD (I-29 mile marker 31).

Timing and storm mode (north):
Elevated convection will be ongoing west of the area during the morning hours, and this will develop east and become surface or nearly surface based through 3 PM CST. A few embedded supercells along with a tornado or two will be possible; however, chasing conditions will be poor at best due to limited visibility from low cloud cover and widespread precipitation.

Synopsis:
A trough continues to dig S and E while a 80kt H5 streak rounds the base late in the period. Overnight, a 60kt LLJ will aid in the northward transport of moisture with 13C H85 dewpoints noted, although this will also result in a large region of ST in northern areas, which will inhibit insolation in the weak November sun. BL moisture will also be meager except in S TX. Soundings from TX through NE indicate SFC moisture of 50-55F and a 100-200mb moist layer.

By late afternoon, a CF will arc S and then SW from low-pressure in NERN NE, while a DL will extend SWRD from a CF/DL intersection near Salina, KS. Two areas will serve as a focus for severe WX, the first of which is just northeast of the SFC low where backing LLVL flow beneath a SWRLY LLJ will result in strong directional shear. Further S along the DL, discrete storms are likely early in storm evolution before a transition to a squall line.

Discussion (south):
Briefly: impressive shear parameters will couple with weak instability. As a result, updrafts will tend to be sheared off. Additionally, a nose of dry air between 3 and 8 Kft will override the DL, and may be detrimental to updrafts. A 100 mile wide axis of SC will extend along and E of the DL from KS S to the Red River, however sufficient SFC heating should still take place for MLCAPEs to increase to 750J/kg.

Discussion (north):
Diurnal heating will be weak with a large area of ST persisting over all of MN, the Dakotas, and eastern NE throughout much of the period. After 20Z, a slot of clearing will develop along and W of US-81 in NE while allowing for a narrow axis of MLCAPE AOB 500J/kg. Elevated convection will be ongoing by 12Z west of US-281 in SD and NE within the region of strong forcing beneath the left-exit region of the ULVL jet. Inhibition will rapidly decrease during the afternoon hours as H7 temperatures cool several degrees with the approach of the upper-level system.

A 50 kt LLJ will retrograde slowly westward as the upper-level system winds up, and SFC-3km SRH’s in excess of 300m2/s2 will result as this LLJ surges over backed SFC flow along and N of the NE/SD border. Deep-layer shear will increase to 50 kts by 22Z as the strongest ULVL flow overspreads the area. An SPC Supercell Composite parameter of between 1 and 2 is indicated, while a modest tornado probability may exist in areas with strong LLVL directional shear where parcels can become SFC or near-SFC based.

- bill, KD0DJG
8:45 PM CST, 11/05/08

[Brandon Lawson]

Since I don't have an opportunity to drive all the way up to the surface low, I will probably stick around home and see what happens around here. Latest NAM run has me thinking about going into northern Texas of all places. It shows precip. breaking out in an area of 1k-1500 CAPE values. This same area has slightly better dewpoints, almost southerly 850 flow, and slightly more veered 500 flow. Of course this is all based on the NAM and will probably change by tomorrow morning. Not to mention, the GFS does not agree with the NAM. But the latest RUC also shows a tongue of moisture poking its way into Southwest Oklahoma. At this point, the best southern target is anybody's guess. Will see what tomorrow's model runs have to offer.

The 00z sounding out of Gainesville, TX looks okay.

EDIT: The 4km WRF shows no precip. breaking out in Texas, perhaps I should reconsider lol :)

[Connor McCrorey]

I agree with Brandon. IF I can chase tomorrow, it will be here in North Texas. Instability is as good as anywhere, and nice, slow storm speeds around 25 kts will be great. Unfortunately I doubt I will be able to get out tomorrow, since I don't get out of school until 4:15 and sunset won't be too long after that. It sure would be nice...

[Erik Burns]

The Red River region ( Gainsville Tx- Ardmore OK and a bit further west )
I have been liking this region since yesterday runs.. Better Terrain, storm motions should be slower then further north, storm mode will be more discrete, better day time heating, better instability... I am going with the NAM on this one.. Not the best setup, but for November I will take it.

Precip broke out this morning in central TX and none of the models picked up on it.. So I will take my chances on the Tail end charlie.. Keep my fingers crossed.:cool:

[Aaron Dooley]

I second that and I'm glad someone brought it up. Erik Burns and I were talking about the lack of focus for that area earlier. If the GFS swings more towards the eta/wrf in a few hours then good. If not, I'll be watching the mesoanalysis page for the parameters as I drive north tomorrow morning.

See some of you out there.

[Angie Norris]

I'm holding out for the Chickasha area. WRF is persistant in breaking out precip by 0Z. CAPE continues to look good at about 1000J/kg, and moisture looks adequate (not impressive, but ok...this ain't May, after all). I'll be checking out what RUC thinks in the morning, and adjusting from there.
Good luck to all heading out!!

[Jason Young]

I think I am going to stay in SC Ok. ( Davis to Duncan area ) . Even thought I feel I will end up in the NE part of the state . I do get the feeling this area will be more hail / wind down here.

[Andrew Stoller]

The forecast soundings for Oklahoma city and points to the south and northeast look pretty darn good! OKC at 00Z shows 1,600 J/kg CAPE, the winds finally have a backing component at the surface and quickly veer out of the southwest by 800 mb, SRH is 225.

I wouldn't be surprised one bit if there was a concentrated cluster of tornadoes tomorrow evening in northeast OK.

Anything north of OKC, more towards Wichita, and the cold front has already come through by 00Z.

Good lord, i can't believe I'm even contemplating chasing tomorrow. LOOOOOOOOOOOOOOOOOONG drive...

[Adam Penney]

I will be out chasing tomorrow for one last hoorah for the season. Will be targeting the area near Ponca City, OK as of now, but will readjust in the morning once I get a good look at the RUC. SE KS through NE OK looks to be the hotspot for any possible tornado action for the southern target. Best of luck to all that will be chasing tomorrow!

[Matthew Fischer]

Well I just made my decision for 2008, i'm going to chase in November. Maybe the last chance this year til my chasecation in may. Target for the time being is between Fremont down to Lincoln to I-29, in NE. Have to pay the northern play since I'm in Chicago. Going to be leaving in an hour or more. Depends on when Adam Lucio and Danny Neal get here so we can all chase. I missed the June storm here in Chicago and missed the August stuff too. I'm not going to miss this. So the jet is going to right in the area, dews are somewhat there. But with the south winds in place already there shall be a nice moisture tongue there. Time to get other things ready.

[Mark Farnik]

The SPC Day 1 Outlook is out and it looks somewhat promising. There is mention of the potential for tornadic supercells, but this is tempered by the fact that the storms will not remain isolated for very long because of the strong low level convergence and large scale ascent, which will force the development of a squall line fairly quickly.
Looking at the Skew-T chart for KTUL (Tulsa) at 03Z tonight, it shows 1400 j/kg of CAPE, a 3 km EHI of 4 and SRH of 395, with a somewhat respectable hodograph and backing S/SE surface winds veering to SW at 850 mb and W/SW at 500 mb.

As of this time, it looks as though there will be about a 2 to 3 hour window of opportunity for several discrete tornadic supercells along and ahead of the dryline. I wouldn't be surprised to see a cluster of 6-10 tornadoes across portions of north central and northeastern Oklahoma into far southeastern Kansas late this afternoon and evening, roughly in an area bounded by Edmond, OK/Wellington, KS/Elk City, KS/Okmulgee, OK.
But these tornadoes will likely occur right at or just after dark, and this setup's chaseability is going to be lessened even further by storm motions, which will be northeast at or in excess of 45 knots.
Not exactly what you'd call an optimal setup...

I'm definitely sitting this one out - my SDS isn't bad enough to justify making a 1,500 mile excursion for a fast moving marginal nocturnal event like this. I'll put the gas and motel money I would have spent on this chase towards buying a new HD camcorder in a few weeks :D

Best of luck to all those who choose to go out today - have fun keeping up with those storms :cool:

[Michael O'Keeffe]

Looking at the 6z WRF it is showing the dryline further west than it has been the last few runs keeping Wichita in the warm sector through 00z and keeping the cold front back towards Great Bend at that time. I am still liking today's chase op so my dad and I will be leaving later this morning for somewhere between Wichita and Ponca City.

Good luck to everyone chasing!

[Adam Penney]

I will also be heading out within the next hour or so to get into position for today's chase. Agree with Michael that the dryline may hang a bit further west, so will head for ICT and then check things out from there. 10% hatched tornado from SPC is certainly promising for a chase day in november. With gas prices at $1.85, I cant pass up this oppurtunity!

[Mike Smith]

For planning purposes, gas prices in ICT are $1.97.

Be safe today and good luck.

[Chris Lott]

SPC is going to upgrade to a moderate risk for the areas of NE OK and SE KS. It looks like Ponca City might be a pretty good spot after all.

[Angie Norris]

I'm still thinking the best chance for daytime storms is going to be central OK. Granted, yes, there will probably be tornadoes up north, but that is going to be after dark...which gets here about 5:45pm or so. The best dynamics are holding back until after 0Z...the dryline doesn't even come through until around 6Z.
WRF and RUC are both breaking out precip in the 21-23Z time frame in central OK and is lining it out by 0Z. Adequate moisture and CAPE should be in place. Shear is quite nice this morning...just look up ;). We've got surface winds out of the SE and lower level clouds are riding quickly out of the SW.
I still like the area S and SW of the OKC metro for daytime convection. For after dark, Ponca City could be a good place to be.

[Mark Farnik]

Son of a... of course, since I decided to not go out after this, it's now evolved into a very tasty looking Moderate Risk setup. My target area I outlined in my earlier post (Edmond, OK/Wellington, KS/Elk City, KS/Okmulgee, OK) is right in the center of the 15% hatched area for tornadoes. Grrr...

But despite that, I'm still somewhat ok with my decision. It would have been a royal b**** of a drive to get down to central OK from Denver and I would have been absolutely dog tired by the time I got down there, and adding in the fact I don't currently have a video camera, having just given my 'old' video camera to my younger sister for a birthday present on Sunday with the expectation that I wouldn't need a video camera until late February:rolleyes: so it really wouldn't have been a fun chase for me anyway.

Sigh. Should have just gone out...

Best of luck to all who are out and about, and I look forward to seeing some nice November tornado footage from y'all! :)

[Andrew Stoller]

Holy crap! I'd say there's a good chance of stronger long lived tornado today in northeast OK, especially after dark. The RUC now shows a secondary 1000 mb surface low by Woodward by 00z which really helps back the surface winds, and it shows up bigtime on all the forecast soundings. Tulsa shows 555 m2/s2 SRH at 06Z with 1,300 J/KG CAPE. RUC pops what looks like 2 supercells southwest of Oklahoma City by around 21Z, so if I were out chasing today (and I'm about to kick my own ass for not going), I'd want to be out by Chikasha by 21Z and follow everything northeast.

:edit: the only inhibiting factor is mid level cloudiness over central/eastern OK, which reinforces my notion of heading southwest where it's clear.

[ablaser]

I too will be heading out today, am liking the upper wave now entering SW KS at 11am. looking more likely that initiation could occur as early as 2pm. will be stationed in arkansas city. and when the storms blast by --i can hit the casino --storms and slots = a good day.

[Chris C Sanner]

A lot of the parameters I like to see will be maximized according to several models in a SW to NE trajectory along I-44 in central Oklahoma. I'm thinking that we should get a storm or two to pop along the dryline in the next 2-3 hours in a moderately unstable environment. If the secondary surface low forms in NW/WC Oklahoma as projected, winds will be locally backed in this area and will enhance the low level shear. Dealing with the metro will be an issue, so it makes the target area rather undesirable for that point alone...either way I fully expect to see a few tornadoes across C/NC Oklahoma and SC Kansas today.

FWIW the record for Tornadoes in Oklahoma in a day (in Nov) is 11 set on November 17, 1958. There were three F3s and six F2s on that day.

EDIT: I want to add that I much prefer the hodograph shape in Central Oklahoma compared to areas further north. The PNC hodo is that dreaded "s" shape, which I have never had any real success with.

[ablaser]

i think you meant record for a day IN NOVEMBER...since 5/3/99 is 11 x 6.


FWIW the record for Tornadoes in Oklahoma in a day is 11 set on November 17, 1958. There were three F3s and six F2s on that day.

.

[Andrew Stoller]

If a storm goes through the atmospheric environment at Tulsa by midnight tonight, things could get ugly. 3Km EHI is 5.1!

http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=018&STATIONID=KTUL

[Chip Redmond]

Storms finally popping west and north of OK city along the dryline. Dewpoints finally in the low 60s out ahead are going to help new storms rapidly develop. The next hour should be very interesting.

Chip