High Plains Drifter

disclaimer:  "The meteorological views/forecast thinking expressed are those solely of the author of this blog
and do not necessarily represent those of official National Weather Service forecast products,
therefore read and enjoy at your own risk and edification!"

April 30, 2009

Chase Forecast: May 1-2, 2009 (Southern Plains)

Filed under: Chase Forecasts/Outlooks,Storm Chasing — Mike U @ 10:52 pm

Friday and Saturday May 1-2 are my days off and after thinking about it for a couple days, I will be chasing.  A fairly aggressive cold front was really worrying me regarding the quality of chaseable supercell thunderstorms, thus resulting in the last-moment decision to go for a 2-day chase.  Friday May 1st looks to be perhaps a spectacular supercell day somewhere along the Red River valley, perhaps along the Highway 287 corridor.  A target centered around Vernon-Seymour, TX has my eye at this point.  There will probably be a dryline/front intersection near here, which is the place to play Friday — right at the nose of the 90+ degree heat intersecting upper 60s to near 70 dewpoints.  Below is a forecast sounding from this evening’s 00z run of the NAM model valid 24 hours from now (when a storm should be in progress) for a location near Seymour, TX.  The hodograph looks very favorable for supercells to go along with the more than adequate CAPE of 3300-4000 J/kg.  This hodograph structure would support slow moving deviant supercell of 10 to 15 knots!  I’ll take that any day of the week :)   This hodograph is not too dissimilar from the hodograph/wind profile of the Garden City/Plymell, KS Supercell just last night (April 29th) which yeilded the incredible "spaceship" supercell and even a few tornadoes.



Saturday, May 2.  This is a little more problematic, but has the potential to be a very nice surprise somewhere across Southwest TX or adjacent southern New Mexico.  I am in favor of playing the area right at the nose of the 300mb jet streak poised to nose right into the Midland, TX area by Saturday evening.  The question is how far west moisture can make it.  The NAM has been very aggressive with the cold wedge nosing down into West Texas, however my gut feeling is that the NAM is probably a bit overdone, and has backed off on this in the latest run… more in line with the GFS and ECMWF.  The ECMWF had me quite excited about Saturday’s prospects when I was looking at it at work earlier today.  The forcing will be very good across the Jal, NM to Midland, TX area by early evening Saturday.  Even if mid 50s dewpoints can sneak back northwest up to Midland-Seminole, TX then that would be enough given the degree of ascent to help get storms going.  The shear profile looks excellent with the west-east oriented jet streak.  The "nose of the upper jet" pattern in the upper levels reminds me of my May 9, 2006 chase in the TX Panhandle, where models struggled in the westward advection of moisture by early evening toward the nose of the upper level jet. 


48-hr GFS forecast valid 00z 5/3 (7pm CDT May 2nd).  300mb Jet streak (in blue) nosing into southern portions of West Texas.

April 27, 2009

Chase Acct: April 25, 2009 (Northwest OK)

Filed under: Chase Accounts,Latest Chases,Storm Chasing — Mike U @ 8:36 pm

It was a last-minute decision to chase, leaving 4:30pm from Dodge City after working an 8am to 4pm day shift.  Since storms would be underway by the time I reached northwest Oklahoma, my thought was just to head to Woodward, getting there by 6:30pm and target a storm by the time I got there.   I intercepted a supercell that tracked northeast along the Canadian River valley north of Cheyenne, OK into Dewey county.  I sat at a location south of Taloga about 6 to 10 miles along US-18, photographing the storm as it approached.  There was another marginal supercell just northeast of the main storm which was fairly photogenic at times as well.  On my way home at around 10:00pm or so, I managed to photograph some impressive staccato lightning.  I have included 8 images below.  A more detailed account will be forthcoming on this blog post soon.

(edit 5/19, 11:55pm CDT):

Full account:

April 25, 2009:  Roll-Camargo-Taloga, OK Evening Supercell & Woodward, OK Staccato Lightning

25 April 2009 had the makings of a potentially impressive mid-late evening tornado event across western Oklahoma as a strong front was expected to stall by late afternoon from the TX Panhandle northeast into northwestern OK.  The front was then expected to lift back north as a warm front by early-mid evening with a very impressive low level jet expected to develop by 8:00pm CDT or so.  I was working the day shift on the 25th, and since no storms were expected across southwestern KS, I was able to get off work right at 4:00pm.  All along, I had no intention of chasing this day, but a last-moment decision was made to go ahead and go after this event.  In some ways, this reminded me of the 9 May 2003 chase I had in central OK — a day in which I also departed Dodge City rather late in the afternoon following a day shift.

Storms were going to be underway by the time I reached northwest OK, and my plan was just to head to Woodward then target a storm upon reaching town.  I was expecting to reach Woodward by 6:30pm, which would give me a good hour and a half of decent light.  There were numerous storms to my east through southeast through south by 6:30pm or so upon my arrival to Woodward {2333}.  Given the storm motions, it was a lot easier to incercept storms to my south or south-southwest then anything east of me.  Hwy 270 (the “Northwest Passage”) goes southeast from Woodward, which would make life very easy for me from a positioning standpoint.  The most interesting storm by the time I reached Woodward was a storm along the Canadian river valley to my south-southwest, near Roll.  There were many chasers on this storm, per SpotterNetwork icons.  In fact, by 6:42pm {2342}, the storm west of Roll was tornado-warned.  This was by far the easiest intercept for me, assuming that no additional storms took over between now and the time I could reach this area.  As the Roll storm headed east-northeast, I headed southeast on Hwy 270 from Woodward {0004}.  Another storm developed northeast of the primary Roll storm, off to my south-southeast.  When I reached Mutual, the sky was getting quite dark, and I could begin to make out a rain-free base well off to my southwest as I continued southeast closer to Seiling {0031}.  I stopped briefly to watch this, however I figured I needed to continue south to get into better position of not only this, but the larger storm farther southwest.

I headed south on Hwy 183 through Taloga, ultimately stopping at what would be my primary stopping place, a few miles south of Taloga, until darkness set in.  I was in a very good position here {0044}, able to monitor both the storm to my northwest and west-southwest.  Both storms had radar rotation.  I was near the Canadian River, and the rolling hills/terrain in this area is quite scenic.  The high spot I found a few miles south of Taloga suited me well and I did not feel like I needed to move from this spot… just letting the westernmost storm approach me.  It was a battle against time, though, as darkness was really beginning to set in after 8:00pm.  I managed to get a few cloud-to-ground (CG) images from the northern storm with my lightning trigger on the Nikon D200.  The western storm was getting closer, and was revealing a nice lowered area beneath the rain-free base.  I was getting rather excited about the prospects of a tornado in the not-too-distant future given the inflow winds I was experiencing, plus the fact the low level jet was expected to be inreasing rather markedly by about this time.  There was one problem, though.  One big problem.  The front was not exactly warm-frontogenetic.  It still had cold front characteristics — it was not lifting north.  As the storm continued to approach between 8:10 and 8:20pm, it was becoming increasingly clear that it was at least slightly undercut by outflow and/or the front itself.  I noticed quite a bit of north-to-south cloud motion with an inflow/outflow interface at the southern edge of the lowered area that was approaching.  Nevertheless, this storm had incredible rotation with it, and it still had an opportunity at tornadogenesis if it could deal with only slight undercutting problems.  A more compact wall cloud formed at the southern periphery of the rain-free base off to the west at around 8:25pm {0124}.  I managed to get a number of decent images of this feature, and I picked a good location to shoot from with a windmill sitting right in front of me.  There was just a brief moment between 8:25 and 8:30pm where I thought tornadogenesis was imminent, but that did not last long.  A massive amount of precipitation was about to wrap around the southern edge of the circulation obscuring my view (as of the impending darkness was enough of a problem).  It wasn’t long before the whole thing was rain-wrapped.

I stayed at that location until about 8:35pm, and then I continued back to the north approaching Taloga.  I wanted to get a few more long-exposure structure images, which I did with some success between about 8:40 {0142} and 8:55pm {0155} or so.  It was clear at this point the storm was outflow-dominant given the elongated shelf cloud structure.  This was the last I would shoot of this storm, so I waited out the passage of the core to the north before beginning my trek back to Dodge {0213}.  I finally headed back north around 9:20pm or so, heading in the direction of Woodward when other storms began to develop in front of me on the highway to the northwest {0244}.  Surprisingly, brilliant staccato CGs were occurring in front of me and to the right of the road, so much so that I just had to stop to setup to photograph.  I photographed CGs between roughly 10:00 and 10:20pm southeast of Woodward {0302, 0319}.  A couple of the staccato CG images from this set were definite keepers, which will be added at some point to my fine-art portfolio.  After that, I began my trek home to Dodge, getting home about 1:45am.


April 26, 2009

Chase Acct: April 24, 2009 (KS-NE Border)

Filed under: Chase Accounts,Latest Chases,Storm Chasing — Mike U @ 11:01 pm

I photographed a couple severe thunderstorms, one of which becoming a marginal supercell with striated updraft structure, near the Kansas-Nebraska border from near Belleville, KS points east towards Washington, KS. A more detailed account will be written on this blog post, but for now, here are a few images from the chase:

(edited 5/20/09 at 12:20am CDT):

Full chase account:

April 24, 2009:  Cold Front Severe Storms Along Kansas-Nebraska Border (Chester, NE to Mahaska, KS to Hollenberg, KS)

I targeted the Kansas-Nebraska border on 24 April 2009 where I thought the western extent of severe storm development would occur along an advancing cold front.  Typically, cold front storms are not exactly photogenic, but I thought I would try my luck.  “Tail-end Charlie” storms, regardless of whether they are along a cold front or not, can sometimes be fairly productive from a photography standpoint with at least decent storm structure.  I wanted to target the nose of the warmest air, also at the nose of the mid-60s dewpoints that were expected to move up into the area from south-central KS.  A look at the forecast hodograph showed a clockwise curved wind profile on the hodograph, which was promosing for perhaps supercell structures.  I left Dodge City late in the morning for a target between Belleville, KS and Hebron, NE by 4:00pm or so.

I arrived in Hebron, NE to a clear sky devoid of any cumulus growth at 3:00pm {2001}.  Where was the western extent of development going to be?  The latest RUC and NAM models seemed to suggest that the western edge would be just a bit east of Hebron, so once cumulus did finally grow along the front to my northeast, I began to head in that direction at about 4:20pm {2126}.  I guess part of this decision was based on the fact that after sitting in one place for over an hour, you start to second-guess your target.  I drove east to Fairbury, reaching that location at 5:00pm or so.  By this time, small storms were beginning to develop — first to the northeast of my location, then north.  Once I reached the small community of Harbine, I took a few photos of the initial cumulus congestus growth to my north {2223}.  Looking back to the west-southwest, all of a sudden there was fairly substantial towering cumulus growth in that direction…as far west-southwest as the Hwy 81 corridor to the south of Hebron where I was sitting between 3:00 and almost 4:30pm {2236}.  I quickly realized that I should have just stayed there, but there was no time to dwell on that — it was time to get back southwest.  I decided to take Hwy 8 through Reynolds and Hubbell, NE to get back to my original target.  There was fairly aggressive development into a severe thunderstorm between 5:40 and 6:00pm very near the Kansas-Nebraska border southwest of Chester, NE {2300}.  The storm was moving to the northeast, which made for a perfect intercept given my location to the northeast of the storm.  The problem was, the storm was moving in an unfavorable direction with respect to the cold front.  While the storm was moving northeast, the cold front continued to move south, and rapid undercutting was inevitable.

I managed to make it to Hwy 81 at Chester, NE about 10-15 minutes prior to the core making it to the highway, and off to the south I went.  I crossed the frontal zone about 5-7 miles to the south of the strongest radar echoes, so this storm was very undercut by the cold front by this time.  At the interface, I noticed a few gustnadoes swirling in the farm field to my immediate southwest, but they were extremely short-lived and very weak at that.  I called the Topeka NWS office to let them know of this observation.  I stopped a few times south of Belleville to get some structure photos between 6:35 and 7:00pm.  By 7:00pm, the development to my west was becoming a bit more interesting to my northwest {2356}, although north of the front.  I finally headed east on a farm road between Belleville and Agenda, following the eastern storm (there were two storms of interest by this time:  one northwest of Belleville and one near Narka {0009}).  I liked the overall structure of the Narka storm so I continued to blast east to stay in a somewhat reasonable position.  I got back on paved Hwy 148 and continued east toward Agenda.  I stopped just east of Agenda to shoot structure to the north, some 20 miles away {0028}.  I had to be at this distance to get the structure shots I wanted since the storm was undercut by the cold front.  Even though the storm was undercut by the cold front, it still revealed some marginal supercell structure with a somewhat tiered elongated updraft structure.  The storm looked less supercellular with time as the structure was becoming more linear in appearance as another cell was forming in the immediate wake of the first.  Nevertheless, there was still decent, somewhat photogenic storm structure at sunset as I was positioned southwest of Washington {0105}.  I photographed the structure of this elongated activity up until shortly before 8:20pm {0115} when darkness was beginning to set in and the best of the structure was fading.  All in all, not too bad of results considering what I was up against (fairly strong cold front causing severe undercutting problems).



April 24, 2009

Chase Forecast 24 April 2009

Filed under: Chase Forecasts/Outlooks,Storm Chasing — Mike U @ 8:59 am

I will be chasing this Friday, as it will be my only opportunity to chase this upcoming pattern due to work.  It isn’t the best setup in the world, but I do envision at least some photogenic storms given the pristine skies out there.  A cold front is pushing south through central Nebraska this morning, but should slow down due to surface heating both sides of the front.  Storms should form in a quasi-linear fashion along the northeast-southwest oriented front.  There is a very small possibility of non-supercell type tornadoes if storm updrafts form in a southwestward propogating manner along the front in a "zipper" type fashion.  The cold front must stall out, though, for this to pan out.  It is not out of the question, though.  Will try to play the western edge of the 55-57F dewpoints where 1700-2200 J/kg CAPE may be realized.  Target:  Belleville KS-Hebron NE by 21z (4pm CDT)

April 20, 2009

Chase Acct: April 16, 2009 (Southwest KS)

Filed under: Chase Accounts,Latest Chases,Storm Chasing — Mike U @ 4:20 am

April 16, 2009 — Daytime lightning images near Sitka, KS

I set out from Dodge City to chase some elevated thunderstorms with the sole objective to capture some daytime lightning images.  I had just arrived home from a very long road trip to Las Vegas, NV for a bowling tournament at around 7:00am.  After about 3.5 hours of sleep, I woke up and noticed decent thunderstorms on radar to the southwest of Dodge City with rather prolific lightning production.  I was immediately intrigued and with the activity moving closer to Dodge City, I decided to make a go at some lightning photography.  I left Dodge around 12:30pm, and about 10 miles south of town, realized I had forgotten my tripod.  Obviously, for the kind of images I wanted, I absolutely needed the tripod, so I went back home to retrieve it.  On the way back home, I briefly visited with Robin Lorenson, Mike Phelps, and Aaron Blaser in town as they were on their way to Colorado for a late afternoon/evening storm chase.  Since I had to be at work at midnight, I could not chase that far from Dodge.   I decided to intercept storms moving north out of far northwest Oklahoma into Clark County, so I drove to Bucklin then south to Sitka.  I reached the storms of interest just south of Sitka where I set up at a location for about 20 minutes.  I did manage to capture a few cloud-to-ground flashes using the Lightning Trigger, although I overexposed one of them at f/11 since the flash was so close!


April 18, 2009

Chase Acct: April 17, 2009 (Southeast CO)

Filed under: Chase Accounts,Latest Chases,Storm Chasing — Mike U @ 6:14 am

This post will be brief — I will write a more detailed account soon, but for now here are a couple images of the partially rain-wrapped tornado I observed near the Colorado-Kansas border yesterday evening at around 8:00pm CDT (7:00pm MDT).  The time stamp on the first image is 8:03:45 and the second image is 8:04:33.  I was photographing this tornado using a telephoto lens anywhere from 80 to 150mm focal length at roughly 1/30 of a second on the tripod.  My observing location was 4.5 miles east of Coolidge about a mile or two north of Highway 50 on an unpaved road.  The view was looking due west in these images toward Holly, CO.  I would estimate this tornado being very close to Highway 50 somewhere not too far from Holly based on radar data at the time.  Even though the primary condensation funnel never fully made it the surface, there were occasional “whisps” of condensation very close to the ground beneath the funnel… as well as at times concentrated rain curtains beneath the funnel, which gave me confidence of at least low-end tornadic circulation at ground level.  More later.

April 17, 2009

Chase Forecast: 17 April 2009

Filed under: Chase Forecasts/Outlooks,Storm Chasing — Mike U @ 6:34 am

"cold core" event in southeast CO/far southwest KS?

I plan to depart DDC at 1330 UTC (8:30am) for Highway 50 corridor of southeastCO somewhere between La Junta and Lamar. -23 to -25C at 500mb (wow!)with lower-mid 40s dewpoints and temperatures rising into the mid toperhaps upper 50s along/south of east-west boundary which is expectedto become more defined (supporting corridor of ~ 800 to 1000 J/kgCAPE). I think an arc of low-topped supercells may develop from west toeast along or near Highway 50 corridor as early as 17z as far west asPueblo. This could be an interesting event for southeast CO andadjacent far southwest KS.


April 10, 2009

Thoughts on 9 April 2009 “cold-core” event (or lack thereof!)

Filed under: General Weather & Forecasting — Mike U @ 6:28 pm

My sudden mid-afternoon pessimism regarding the "cold-core" setup across south-central Kansas yesterday was realized.  Storms did develop in the target area as mentioned in the forecast blog posts, but none of them were tornadic based on any reports.  I say "based on any reports", because between 2205 and 2215 UTC (5:05 and 5:15pm), KICT WSR-88D revealed a very interesting, very small scale shear couplet with at least 3 volume scans of temporal continuity.  The 2210 volume scan revealed what I believe is a TVS signature about 6 miles northwest of Goddard.  It was only on one volume scan, and the entire shear signature was gone after 2215 as it evolved very quickly.  Was there a brief tornado here?  That brief TVS was only 11 miles from the KICT radar (with the center of the beam hitting an altitude of only ~ 500 feet above radar level at that range), and since the storm was so close to the KICT radar, the reflectivity looks unorganized and messy at best.  A look from KDDC at that time revealed a 50dbz core extending up to about 20 thousand feet above this area.  That brief TVS was interesting to say the least and is very convincing given temporal and even elevation angle continuity.  Whatever happened, happened fast, probably less than a minute, and since there were no chasers out there that I know of west of Wichita at that time, if an event occurred there, it probably wasn’t observed.  Who knows.  I’m not aware of any damage reports from this location.  See the 3-image composite below:

Storm chaser Dean Cosgrove sent me a couple links to images he captured of a well-defined funnel cloud from one of the storms along the occluded front in northeastern Pratt county near Preston at around 2135 UTC (4:35pm CDT).  Below is one of the images.

Why weren’t storms more productive tornado wise?  This is very difficult to answer with any degree of confidence since I haven’t done an in-depth post analysis of the event yet, however I think that southwesterly dry winds were converging too close to cooler northeasterly winds just to its north.  There wasn’t a wide enough favorable airmass in between the dry southwest winds and cool northeast winds for storms to thrive long enough in order to take advantage of the rich ambient vorticity that was around.  I think storms simply became undercut too quickly by cool northeast winds that resided immediately north of southwesterly surface winds.  There really wasn’t much of a corridor of easterly or southeasterly winds (all that’s needed is about 20 to 40 mile wide corridor based on my experience from 26 October 2006 and 10 November 2008), and on 9 April there wasn’t even that, I don’t think.  Again, I will have to look at the mesoscale data in order to help answer this.  I also think the advancing cold front from the northwest was too much for the surface-based storms as well.  Intense convection simply didn’t last that long.  I also think this event lacked "converging boundaries".  Both on 10 November 2008, and 26 October 2006, it was interesting to see on satellite imagery hours before the event occurred, the presence of cumulus cloud lines marking surface boundaries…which ultimately converged on one another in a constructive manner favoring tornadogenesis.  I don’t think this occurred yesterday from what I saw in the data.  I think this may have to do with the positioning/evolution of the 400mb PV anomaly.  On 10 November and 26 October, the 400mb PV anomalies were very focused and even more mesoscale than yesterday.  Yesterday’s 400mb PV anomaly was broader as it moved east, leading to a much broader surface response in the wind field.  I don’t think the vertical vorticity axis was tightly concentrated over one specific area, but was rather strung out all along the occluded front without much room for storms to take advantage of before becoming overwhelmed by either chilly northwest surface winds or northeast surface winds.  I’m thinking out loud here, but these are my early impressions on yesterday.  These are very mesoscale details that make a huge difference in whether a "cold core" event is productive or not.  This kind of detail can not be forecast with much ease at all.  I more than likely would have busted yesterday had I chased, as I targetted Kingman.  Congrats to Dean Cosgrove for at least intercepting something somewhat interesting from one of these short-lived storms.


UTM Photo of the Month — April 2009

Filed under: Photography,UTM Updates — Mike U @ 1:18 pm

April 2009

The Rear-Flank Downdraft (RFD) Clear Slot

On myfirst chase of 2009, March 23rd, I intercepted a small supercellthunderstorm near Kingman, KS. This storm, albeit small, revealedinteresting supercell structure as it tracked north toward CheneyReservoir. A nebulous wall cloud is also seen here in this image on thecyclonic shear side of the RFD clear slot. Details of this image: NikonD3 body, 22mm focal length, 1/5000s @ f/3.2, ISO 200.


April 9, 2009

Update #3 on 9 April 2009 “cold-core” setup forecast

Filed under: Chase Forecasts/Outlooks,General Weather & Forecasting — Mike U @ 2:05 pm

Below is a visible satellite image as of 1930z.  I am NOT a fan of all the mid level cloud that has developed over my target area in the zone of maximum surface vorticity at the nose of the west-northwest surge in dewpoints toward south-central KS.  I’m not sure what to make of this.  The nose of surface heating is displaced south of the moist axis by a fair distance, which is something I’m also not a fan of.  I remember at this time of the day both on 10 November 2008 and 26 October 2006, there was NOT a large area of mid level cloud that spontaneously developed across my target with the best heating displaced south.  I expected a surge in warm air northward toward Kingman-Wichita, but it is not happening.  19z obs show 70 at Alva, 71 at Medicine Lodge, and 73 at Wichita.  The best warm surge is south of ICT across far north-central OK…thus am now thinking that the western limit of tornadic storms may be I-35 south of Wichita, perhaps.  If I was in Kingman right now (like I probably would be at this time), I would seriously be considering heading southeast toward I-35 corridor down into Sumner County.  This isn’t an easy virtual chase, and is not as "obvious" to me all of a sudden as I thought it may be like 10 November 2008 and 26 October 2006.  No two "cold core" events are the same, that’s for sure, which is why it is a dangerous game to use comparisons to historical events like I do, LOL!  History never repeats itself, but it does like to follow a rhythmic beat, which is why I think conceptual models and events of the past are helpful in forecasting.  If this event busts, it isn’t the first time and certainly won’t be the last!  That being said, it is still 20z at the time of this writing, so a lot can happen between now and 00z.  In fact, I’m interested in the cyclonically rotating echoes on the DDC and ICT radars south of Pratt.  There’s a 45 dewpoint in Pratt at 20z, so who knows.  There could be a fluke brief tornado in Kiowa or Pratt counties since it’s so cold at 500mb.


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