by Bruce Haynie
Sep-Oct 1995 Storm Track
© Copyright 1995 Bruce Haynie
Al Moller brought my attention to the developing situation the night before, although, I didn't believe supercells were possible during the month of July in the Texas panhandle. After giving Al a hard time about his forecast, I thought about the possibility that he was right. The following day, I went to the weather office and began to analyze the weather situation. The first thing that caught my eye was the dryline. A closer look revealed a dryline bulge in the surface analysis and mixing ratio chart. What caused this to happen?
A weak surface low had developed in eastern New Mexico in response to an upper level disturbance approaching the region as observed on the water vapor imagery. As surface pressures decreased in eastern New Mexico, east-southeast flow became established across the Texas panhandle creating great moisture convergence and a good low-level turning of the winds. I still wasn't convinced anything was going to happen until I saw the upper level winds upstream. They were quite strong for this time of year and I expected that winds aloft would increase throughout the day over the Panhandle.
I departed Lubbock around 4pm, and headed northwest on Highway 84 to Littlefield, then turned north on Highway 385 and ended up in Hereford. Along and just east of the north-south highway, a line of towering cumulus bubbled continuously with no increase in development for about two hours. I had time for a leisurely dinner around 6 pm. After dinner, I headed north to Vega. I saw the towering cumulus at the north end of the line develop into a cumulonimbus. I also saw a large thunderstorm to my distant northwest with overshooting tops. This storm was located in southeast Colorado moving southeastward into the Oklahoma panhandle.
I had a choice to make. Do I continue north to Dalhart and intercept the well developed storm (a long chase), or do I follow the new convection just to my east. After some thought and meandering, I headed east on I-40 and caught the nearer storm as it moved over Amarillo. A persistent wall cloud grabbed by attention. The cloud base also was rotating. I turned south on FM 1258 just east of Amarillo. Meanwhile, the rotation at cloud base tightened up. I stopped about six miles south of I-40 and took still photographs of the storm which was only five miles to the east. Soon after, a wide funnel developed at the base of the wall cloud. Then, a white, needle shaped tube developed underneath the larger funnel and started working its way to the ground. An orange debris cloud started churning about six miles to my east. Full condensation touched the ground moments later. What a sight! The funnel seemed to evaporate but the debris cloud remained. A couple of minutes passed before the funnel reappeared and a white cone/cylinder formed. The funnel seemed to disappear as the dust cloud enveloped the tornado, then emerged from the dust as a long rope apparently as the rear flank downdraft kicked the tornado out to the south. Finally, the tornado dissipated around 8:20 pm, after taking 65 slides -- some of my best photos ever.
TEXAS/OKLAHOMA PANHANDLES AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO, TX
1020 AM CDT SUN JUL 23 1995
ALL PRECIP HAS LEFT FCST AREA AND MOVED INTO OK AS OF MID MORNING. OVERNIGHT AND MORNING CONVECTION HAS LEFT OUTFLOW BOUNDARIES LURKING ABOUT THE REGION RESULTING IN DISORGANIZED WIND FIELDS AT THIS TIME. WILL TWEEK AS SUCH IN ZONES.
MODIFICATION OF 12Z AMA SOUNDING FOR AFTN TEMP OF 94 AND DEWPOINT OF 55 ALONG WITH A 700MB TEMP OF 13C RESULTED IN FAIRLY UNSTABLE ATMOSPHERE WITH A B+ APCHG 2000. IN ADDITION, LOCAL PROGRAM WAS RUN WITH MODIFIED SOUNDING PARAMETERS AND RESULTED IN HAIL REACHING WELL INTO SVR CRITERIA ALONG WITH HIGH WIND POTENTIAL. THUS, AGREE WITH SELS DAY1 OUTLOOK (SLIGHT RISK) AND WILL RETAIN MENTION OF SVR. HOWEVER, IT WILL TAKE JUST ABOUT ALL AFTN TO BREAK CAP SUFFICIENTLY. BIGGEST THREAT FOR SIG CONVECTION SEEMS TO BE DURG SECOND PERIOD AS A FAIRLY STRONG VORT LOBE APCHS PNHDLS FROM SCNTRL UT. ..ANDRADE..