Basic summary of storm:
April 15, 8:00 PM - Interception and observation of an extremely severe and tornadic thunderstorm that paralleled Highway 54 and to its northwest from near Dalhart, Texas in Dallam and Hartley Counties and points northeastward as far as Hough, Oklahoma in Texas County. The storm was a cyclic classic to HP supercell storm. The core of the storm was not penetrated directly. At least 3 tornadoes were observed with this storm near Eva, Oklahoma in Texas County around 8 PM, CDT from along Highway 412. The first tornado was an elephant trunk, which lasted a few minutes. The second, forming just N of the first was a large stove-pipe tornado lasting about 5 minutes. The third west of the first two (that formed on the forward flank of the mesocyclone), was farther west and became a wedge tornado. This tornado quickly became rain wrapped and view of it was lost as the storm continued to the NE. Very heavy rains, hail to 1" (during indirectly penetrating the storm), lightning, and winds near 70 MPH were encountered as well. The storm inflow SE of the storm was at least 60 MPH, pulling dirt and dust off the ground near Stratford, and ingesting it into the storm main updraft prior to cyclic tornado genesis. The storm core had hail to baseball sized or larger. The storm had a striking visual appearance, with a "stacked plates" effect, inflow / beavers tail features, mammatus, and RFD clear slot. The storm remained over mainly rural areas, with damage being mainly to powerlines. The storm eventually continued NE after dark to the NW of Liberal, Kansas, before weakening and merging with a storm cluster. The storms were caused by a low pressure area, surface heating, strong upper level low, and advancing dryline. A 2016 Toyota Rav4 was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was also valid for the area until 10 PM CDT.
Pictures:
1). View of supercell storm in Texas County (just before it started to produce tornadoes)...
2). First tornado SE of Eva, OK.
3). Second (with weaker twin to it's left) stove-pipe tornado SE of Eva, OK.
4). Third wedge tornado behind the forward flank / in the main meso!
Below is the detailed chase log:
This was a "spot" chase trip during the late week / weekend of April 14 through 17, 2016 with April 15 and 16 being the days available for chasing. After clearing my work schedule for Friday (April 15), the plan was to fly out to Denver, Colorado (late on April 14) and target the areas from SE Colorado into the Oklahoma and Texas Panhandles, and return to Chicago early on April 17. The anticipation of chasing these days started a week in advance, with a strong upper air low (after crossing the Northern Pacific ocean) forecasted to be over the western USA by Friday, April 15. Models progged this upper low to stall and weaken due to a blocking ridge eastward over the US Midwest and upper MS river valley. With a time constraint and pretty much April 15 being the "main" chase day, I opted to fly out and rent a vehicle instead of driving my own.
The initial plan was to leave Chicago late evening on 4/14. After getting a report my flight was delayed, I quickly changed for an earlier on-time flight and arrived into Denver during the evening of April 14. I picked up the rental vehicle, a 2016 Toyota Rav4 SUV, and spent the night near Aurora, CO east of Denver. With heavy snow forecasted later in the period, I opted for an upgrade to the SUV rental. I also changed my morning return flight on Sunday (April 17) to the afternoon to avoid any issues with the predicted heavy snow that was to affect Denver on April 16 through the morning of the 17th. Upon waking up early on April 15th, I forecasted and decided the right place to chase would be in an area from SE Colorado (around Springfield), southward into the Oklahoma Panhandle and as far as the area north of Amarillo, Texas.
I started out by heading east on I-70 to Limon, then southeast on Highway 287 / 40 through Kit Carson and eventually through Lamar and Springfield (having lunch there). Meanwhile, the Storm Prediction Center (SPC) had an area in a enhanced risk, with a 5% tornado, 15% wind, and 30% hatched hail in the outlook, which extended from SE Colorado and into Texas along an axis centered north of Amarillo and as far south as Lubbock. A developing dryline, and low pressure area in NE New Mexico were becoming apparent, with a dewpoint axis in the 50's. While heading south near Lamar on Highway 287, a cluster of highly sheared, agitated cumulus was noted to the west. This was not the primary target area, but this later formed into a tornadic thunderstorm that would produce the first tornado of the day near Eads, Colorado in upslope wind flow to the south of a slow moving cold front.
By mid to late afternoon, I entered Oklahoma via 287 / 385, through Boise City, and eventually the northern Texas Panhandle near Stratford. SPC issued mesoscale discussion 385, and subsequent tornado watch box 91 valid until 10PM CDT for my area. While mulling over the intense tornadic storm far to the north in SE Colorado, I noted convective initiation to my southwest just east of the TX / NM border. I headed southwest through Dalhart along 54 where I intercepted the cluster of strong and severe storms. One very intense cell intensified and became the main storm of the day. This supercell storm would track northeast back near Dalhart and continue northeast into Oklahoma and eventually produce tornadoes from near Eva, OK in Texas County and northeast of there at dusk. The storm remained NW of, and paralleled Highway 54, which made that route helpful.
Tornadoes were intercepted with this storm on Highway 412 near Eva, OK. I continued with the storm to near Hough, OK along Highway 136 and ended the chase after dark. I headed back down 136 to 54, spending the night back in Dalhart, Texas. Hail (up to 1") was also observed during an overnight severe storm in Dalhart. April 16 was another chase day, although not expected to be as active as the day before. The target area was pretty much near Amarillo and points east and southeast of there. A Pacific cold front and dry line interaction was involved with this days setup, and after forecasting it was apparent I did not have to travel very far. I left Dalhart via Highway 87 to Dumas, then south to Amarillo for lunch at the Big Texan steakhouse (a must for chasers in that area whether you catch tornadoes or not)!
A strong thunderstorm (due to an on-going line of strong and severe storms) passed over the restaurant and dropped marble sized hail. The SPC again had a similar outlook for this area, maybe shifted a bit east or southeast, with a tornado probability of 5%, and hail and wind probabilities both at 15%. Mesoscale discussion 395 and subsequent tornado watch box 93 valid until 9 PM CDT was also issue for this area, with the lower 2/3 of the watch area having the highest tornado threat. After lunch, I headed east on I-40 to highway 207, observing a rotating storm NW of White Deer. This storm weakened as outflow under-cut it, so I headed back to I-40 east, then to Mclean, and south on 273 to Hedley. The "tail-end Charley" supercell was intercepted from SE of Clarendon near Lelia Lake and acquired intense rotation (with a possible broad / brief tornado).
This storm was followed back north and northeast by back-tracking along highway 273 until it weakened NW of Shamrock. I ran into many storm chasers, including Randy Hicks while on 273. The chase was completed near Shamrock and back on I-40. I headed back west to 273, and NW through Pampa and Borger, picking up 152 West to meet highway 87 and eventually 287 / 385 north out of Dalhart and back across the Oklahoma Panhandle and into SE Colorado. I continued as far as Lamar, Colorado, by 11 PM for the night. As I arrived in Lamar, I was pulled over briefly for a mistaken U-Turn, but wound up having a great talk with the officer (no citation issue), who was amazed on my storm chasing endeavors! I got a drink at the local bar in Lamar, and stayed at the hotel on the north side of town. April 17 was pretty much a travel day back to Denver.
I headed back up 287 to 40 and eventually I-70 via Limon. Near Hugo, CO, the snow swath "gradient" was encountered. By Limon and into Denver on I-70, heavy blowing snow and wintry travel was encountered. This was the tail end of a major winter storm that dumped up to 3 (or even 4) FEET of snow in the Denver area. I progressed slowly on I-70 (roads were not that bad) back into Aurora. After having lunch, I headed to the airport, returned the rental vehicle, and flew back to Chicago (luckily my flight wasn't one of many cancelled). This was the end of this chase trip. Total mileage was around 1,120 miles.
