Total Distance: 170 miles
Target Area: South-central OK / North-central TX
Chase Area: Ardmore (BUST)
Maximum SPC Risk category: Moderate

Not much of a log necessary. Surface-based convection never had a chance in the 60-80kts 0-6km shear environment and only ~1000j/kg sbCAPE. A nice supercell did develop after dark and tracked from near Throckmorton to Ada, but that was well after we had arrived back in Norman. The GFS had forecast a near-Armageddon type of outbreak days before, but as the event neared, the trough become progressively more positive-tilt and 57-60F dewpoints just couldn'd allow for significant CAPE to develop and for the CINH to diminish enough to provide for surface-based initiation on a weakly-convergent dryline.

Total Distance: 600 miles
Target Area: Independence (KS)
Chase Area: Near Independence to Fort Scott (KS) to Miami (OK)
Maximum SPC Risk category: High

The models had been forecasting one of those once-a-decade type of March synoptically-evident tornado outbreaks for several days prior to this event. Unfortunately, the GFS had forecast similar high-end setups twice within 7-9 days previous to 3/12, neither of which really panned out. So, there was a little skepticism regarding model forecast verification, which required cautious optimism on my part. In addition, NAM and GFS runs the previous couple of days indicated that the dryline would push into Arkansas by afternoon. Since it was spring break, I was thinking about biting even when it looked like that would be the case.

Total Distance: 300 miles
Target Area: West of Watonga and South of Woodward
Chase Area: Taloga to Oakwood to Watonga to Omega
Maximum SPC Risk category: Slight / None

Well, it was time to test the whole cold-core chase idea... With a very strong mid-level low approaching from the southwest (500mb temps in the -24 to -25F range), and the warm sector well displaced to the southeast, it looked like a semi-classic cold-core mini-supercell event on which Jon Davies has helped shed light. The SPC noted the potential early in the day, but ended up dropping any risk in northwestern Oklahoma by afternoon. With a nice boundary in the area, sufficient shear and dewpoints, and nice insolation along that boundary, it really looked like it'd be worthwhile going on the limb to give the day a chance.

Total Distance: 330 miles
Target Area: Hollis, OK, to Childress, TX
Chase Area: BUST
Maximum SPC Risk category: Slight

Not much of a log needed. It was apparent beforehand that initiation would be an issue. With the upper-level system coming through after dark, I knew we were relying entirely on dryline convergence for initiation. Despite marginal-moderate CAPE and decent shear, forcing and convergence proved too weak to initiate any convection. The Cu field began to dissipate by 5pm, and we turned around soon thereafter.

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Total Distance: 440 miles
Target Area: Duncan
Chase Area: Marlow, OK, to McAlester, OK
Maximum SPC Risk category: Moderate

I waited around OUN to see if the convection in southwestern OK would break up into discrete storms. I (with Jana Lesak, Gabe Garfield, Justin Walker, and *forgot the name,,, sorry!*) were originally planning on hitting up the storm near I40 to the west of OK, as it appeared to be becoming discrete. However, as we were leaving OUN, the cells in southwestern OK looked to be breaking up a bit, so we headed south in hopes that some insolation down there would help the cause.

Total Distance: 390 miles
Target Area: Shamrock, TX
Chase Area: Willow, OK, to Clinton, OK
Maximum SPC Risk category: Moderate

Finally, a more classic dryline setup presented itself, as deep moisture surged northward ahead of a strong shortwave entering the southern plains. As this ocurred, a dryline was progged to setup across the central OK/TX panhandles, south and southeast of a surface low in southeastern Colorado. For the first time this year, models were forecasting strong instability to develop in southwestern Oklahoma (~3000 j/kg CAPE) as dewpoints were progged to be in the 64-69F range (in the end, we saw 59-62F, again a huge model overforecast of dewpoints, as we've seen a few times already this year). While cirrus was an initial concern in the days leading up to the event, a look at the morning visible satellite showed that it would be a problem.

Total Distance: 560 miles
Target Area: Bartlesville, OK
Chase Area: Bartlesville, OK, to Carney, KS, to Pryor, OK
Maximum SPC Risk category: High

Another synoptically-evident severe weather setup today, with a VERY deep cylone along the central NE/KS border (~980mb) associated with an intense cut-off low moving out of the western US. The operational models weren't consistent with the location of the dryline, however. Several days before the event, the models began shifting the dryline forecast position from western MO/AR, westward to near the I35 by afternoon. However, starting the day before the chase, the NAM began shifting the dryline forecast position farther east again, with the 12z 4/5/06 run indicating that the dryline would be in western MO by 0z. With that trend, opposite of what we had seen up to that point in the season, I was feeling quite pessimistic about the chase potential, and I had full plans to stay home.

Total Distance: 175 miles
Target Area: Kingfisher, OK
Chase Area: In and near El Reno, OK
Maximum SPC Risk category: Moderate

The models had been all over the place with the forecast for April 24th, but the general setup involved a surface low in western OK, with a strong cold front diving down the lee of the Rockies (with temps in the 30s in WY/CO/KS/NE during the afternoon). We were going to see (FINALLY!) real mid-upper 60 dewpoints into Oklahoma by afternoon! I was planning on chasing to the east and northeast of wherever the surface low was going to set up. Mid-level flow was strong enough to yield 40-50kt deeplayer shear, and CAPEs were anticipated to be near 4000 j/kg by afternoon. There was a peculiar weakness on the flow near 250mb (south at 20kts across central OK), but that wasn't going to be enough to keep me home, obviously.

Total Distance: 500 miles
Target Area: Childress to Guthrie (TX)
Chase Area: Childress, TX, to Olustee, OK
Maximum SPC Risk category: Moderate

I went out with Robin, Dan, and JR, targeting an area near and south of CDS. We arrived in CDS and hoped that the convection that fired around 1pm west of ABI and south of Quanah wouldn't become a problem. By mid-late afternoon, new convection was developing along the cold front - dryline intersection to the west of CDS. We followed this intersection southward for a bit, but it was becoming quite obvious that the cold front was undercutting the convection. It's never a good thing when you have a southward moving cold front with storms that are moving NE slowly. Storms would develop sw of CDS, but then quickly get undercut.

Total Distance: 330 miles
Target Area: Woodward, OK, to Ashland, KS
Chase Area: BUST
Maximum SPC Risk category: Slight

With a group of high school students visiting from Windom, MN, we opted to head northwest, with the potential for supercells. Long story short -- drove to Woodward, at which time it was obvious initiation was not going to occur anywhere close. Visible satellite imagery showed clear skies, with shallow moisture and a cap preventing much in the way of anything notable. We spent about 15 minutes in Woodward before driving back to OUN. Clear sky bustola.

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Total Distance: 275 miles
Target Area: Seminole to McAlester, OK
Chase Area: Wewoka to Stuart to Atoka, OK
Maximum SPC Risk category: Moderate

Went out with the Windom students again. The first day of true Gulf moisture in the area, with low-mid 70s dewpoints, a nice outflow boundary near and just south of I40, and decent shear led to pretty good optimism about chase prospects. And yeah, and CAPE was >5500 j/kg in places. Initiation was a concern early in the day, but 18z and 19z soundings indicated that this was not going to be a substantial issue.

Total Distance: 780 miles
Target Area: Concordia, KS, to Hebron, NE
Chase Area: Near Concordia, KS
Maximum SPC Risk category: Slight

Well, after a couple of weeks of very deep, persistent troughing in the eastern US, the Gulf of Mexico had been pillaged a couple of times by strong cold fronts. The propsects for getting any >65F dewpoints north of I40 looked tough, but things looked good enough to take the long haul northward. With the next 10 days looking quite poor from a chase perspective, I had extra motivation to grasp at any straws mother nature was holding.

Total Distance: 500 miles
Target Area: Perryton, TX
Chase Area: Arnett to Reed, OK
Maximum SPC Risk category: Slight

Another marginal chase, with mediocre CAPE forecast and marginal shear courtesy of relatively weak (<35kts) 500mb flow. However, given the history of the upper-level pattern the past few weeks, and the prognosis of another big east-coast trough, there really was not other choice than to chase what was given...

Highlights: southward-propagating supercell, half-dollar sized hail (possibly larger), 69mph measured winds.

Total Distance: 500 miles
Target Area: McLean to Clarendon, TX
Chase Area: Groom to Shamrock, TX
Maximum SPC Risk category: Moderate

Another disappointing chase to fit in with the majority of 2006. As a high-amplitude, seasonally-strong trough moved into the plains, strong shear profiles were progged to be juxtaposed with moderate to strong instability. As has been the case for the vast majority of the season, however, low-level moisture was pitiful, resulting in >2000m LCLs and outflow-dominant storms. What a waste of nice wind profiles... I was weary of playing anything north of the Texas panhandle owing to southerly 250mb flow by afternoon as the trough swung out from the west, so we (Dan Dawson and I) targeted the central and southern TX panhandle. Here, midlevel and upper-level flow was going to be more veered given its proximity to the base of the trough. The majority of the time, the low-level veering - upper-level backing wind profiles tend to lead to MCS development, which was indeed the case up in KS and NE.

Total Distance: 500 miles
Target Area: Kismet to Moscow, KS
Chase Area: Ashland, KS, to Gates, OK
Maximum SPC Risk category: Slight

We (Robin, Dan, and I) decided to give 2006 another try. Pfff. High-based convection developed owing to high dewpoint depressions. Flow aloft was relatively weak as well, so shear wasn't overly impressive, except for areas along and northwest of an outflow boundary that stretched from the western Texas panhandle north-northeastward into northcentral KS, where low-level flow was backed to easterly. The best chances for tornadic development appeared to be in far eastern CO and western KS, but I wasn't willing to make the 6+ hour drive from Norman for what was still a rather marginal setup.

Total Distance: 520 miles
Target Area: Arnett to Canadian to Meade
Chase Area: Gate, OK, to Ashland, KS, to Coldwater
Maximum SPC Risk category: Slight

Wow, apparently Ma' Nature switched May with September. A very nice, deep trough in the western US was the instigator for the first chase day in September 2006. The next day was supposed to be "THE day", so this day was more of the "day-before-the-day" type of event. Moisture wasn't terribly impressive, but we were hoping it'd be enough to result in sufficient CAPE in the very strongly-sheared environment. With intense deep-layer and low-level shear in place, we were just hoping the dewpoints and CAPE would be sufficient. A leading shortwave trough wasn't enough to initiate convection through the mid-afternoon, but we noted a rapidly-approaching secondary shortwave-trough rotating through CO and NM -- I just hoped it would make it into the area before the sun set. It was close...

Total Distance: 510 miles
Target Area: Arnett, OK, to Coldwater, KS
Chase Area: Coldwater, KS, to north of Pratt
Maximum SPC Risk category: Moderate

I hadn't planned on chasing this day, since Kim and I were going to go to the state fair, and it looked like veered surface flow would negate any tornado threat in an otherwise highly-sheared environment. The main action looked to be farther north into NE, SD, MN, and IA. By Saturday morning, however, it was apparent that surface flow wasn't going to be terribly veered, and it looked like a setup that I couldn't miss. Dan, Gabe, Robin, Kim, and I charged up the northwest passage. The overall environment was looking quite good for tornadic supercells.

Total Distance: 420 miles
Target Area: Denton, TX, to Gainesville to Sherman
Chase Area: Ardmore, OK, to Antlers
Maximum SPC Risk category: Moderate

I sat with Gabe, Dan, and a few other chaser-friends in Ardmore for several hours this afternoon, waiting for one of the TCu along the dryline to take hold. I became quite discouraged by 6pm, after having watched TCu after TCu lose the battle of initiation. We meandered southward a little based on satellite observations of persist "clumping" of TCu just across the Red River in northern Texas, before heading eastward to catch up with a shower that had developed southeast of Ardmore. It appeared as though a new cell developed to this cell's southwest, so we dropped southward to get into better position to watch this new cell. A bad road option near Coleman (red dirt+rain=bad) resulted in us having to drop southward to Kenefic and Caddo; in hindsight, we should have gone north to Wapanucka instead (as Amos and Eric did).

Total Distance: 323 miles
Target Area: Blackwell to Ponca City, OK
Chase Area: Near Arkansas City, KS
Maximum SPC Risk category: Slight

A nice, compact, powerful bowling-bowl type of upper low was forecast to approach the southern plains. Early model runs indicated that it was pass through Oklahoma during the overnight hours, minimizing any local severe threat and pushing the main threat into the southern Mississippi River valley. As the time neared, models slowed down the progress of the storm system, enough so to get me excited to chase again. Shear would be very strong (00z OUN sounding verified nearly 80kts 0-6km shear!), but marginal moisture and relatively weak lapse rates would limit instability. By mid-morning on the day of the chase, a wind shift made its way a couple of counties to the east of I35, which dropped dewpoints and made the worry about limited instability even more of a worry. Gabe and I briefly discussed a possible cold-core play in southwestern Kansas, but we liked the shear profiles along the warm front near the Oklahoma / Kansas border enough to stick with warm-sector activity.

Total Distance: 360 miles
Target Area: Denton to Gainesville to Paris, TX
Chase Area: South of Gainesville, TX (Bust)
Maximum SPC Risk category: Slight

Not much a log necessary... Very intense cold front was to come plowing through the Plains. Sufficient moisture had returned to the area (Tds >60) to support marginal to moderate CAPE (~1000-2000 j/kg) in the warm sector, while strong wind fields at all levels created rather substantial shear. However, the cold front moved quick enough, and the storm motion relative to the front was aligned, such that the front undercut any cellular convection that tried to persist in the warm sector. A couple of discrete cells did develop near the DFW metroplex, but they dissipated or moved behind the front, killing any tornado threat.