Chase log written by David Reimer. For Jenny’s separate chase log for March 25 click here.
The days you don’t expect much are the ones that too often become memorable. Wednesday, March 25 was a category 4 severe weather risk day (a Moderate Risk) – the first of the 2015 storm chase season. After our first chase of 2015 the previous day in Missouri and a quiet 2014 season we were ready to get back out into the field. Tornado potential for the day looked marginal but ingredients were coming together for organized hail-producing storms. Our plan was to stick around home in Norman for the day and await thunderstorm development about 30 miles west of Oklahoma City. The local nature of the storms allowed for a casual schedule and to lounge around until the mid-afternoon hours. When it appeared thunderstorm initiation was imminent we headed west to Blanchard, Oklahoma to time-lapse the developing storms. It took a while for the storms to become organized and even then they looked outflow dominant thus resulting in a diminished tornado risk.
When storm chasing there are a few different modes we use depending on the situation. For days where the tornado risk is pretty much zero we’ll plan on playing in the hail or conducting storm photography. With a tornado risk we’ll position ourselves in a good spot to observe the storm’s updraft and any potential tornado development keeping outside hail cores with plenty of escape options. With the tornado risk looking NIL and an impressive storm west of El Reno, Oklahoma we decided to head up there to intercept it at close range. Around 6 PM we made it to the south side of El Reno on Highway 81. The same area was impacted by the May 31, 2013 violent tornado and this was my first time back chasing in that area since that event. Ironically we ended up on the same roads this day as we did back on 5/31.
As the storm approached from our west it was obviously a supercell – albeit elevated and high-based. Radar data along with visual indications showed this storm was producing serious hail – both in size and quantity. Very strong outflow winds were also being detected on radar. Around 6:10 PM the radar showed a hook-echo on radar but with outflow well ahead of the storm. We weren’t concerned about any tornado risk at this time. However, this storm did something unusual. It had a rotating wall cloud as it approached our position and rain curtains below it were obviously rotating. While we couldn’t determine much in real-time visually due to the rain our enhanced dash cam video does suggest there may have been a brief, very weak tornado. Evidence is not conclusive enough for me to count it as a tornado – but still it is not something you’d expect from a storm undercut by cold air. Shortly thereafter we needed to reposition back east to Highway 81 just south of Interstate 40.
Having purchased a new vehicle during the off-season I wanted to add some hail dents to the car. Storm chasers often consider the number of hail dents on a car as a matter of pride. We elected to core punch and see what the storm had to offer. It certainly did not disappoint! We experienced about five minutes of golf ball size hail being driven horizontally by 60-70 MPH winds. Video included with this log will show that it looks/sounds like were driving as we sit still. If not for the hail it would have been nearly identical to riding out a strong tropical storm with little visibility due to all the rain. This storm had serious punch to it and was moving east quickly towards the Oklahoma City metro. Once the brunt of the hail core passed to our east we elected to follow it on Interstate 40. We never could get back ahead of it but we spent 30 minutes driving in the hail core as it tracked over Oklahoma City.
Something rare occurred as the storm moved into Oklahoma City and Moore. The supercell caught up to the outflow boundary that was keeping it undercut – likely catching back up thanks to its accelerated storm movement and widespread damaging winds being produced. A focused area of rotation was able to develop and produce a tornado over Moore – impacting some locations that were levelled on May 20, 2013. This tornado was comparatively weak to the 2013 tornado but still caused damage, including on Interstate 35. We arrived at where the tornado crossed Interstate 35 in Moore about 5-10 minutes after it occurred. Several vehicles had been flipped and a tanker carrying gasoline was leaking. After briefly recording ENG (Electronic News Gathering) video we continued south a few miles to Norman where we concluded our chase by documenting a new storm moving over the city. It produced some hail and wind but our chase was concluded.