UPDATE: 19 May 2010 / 11:30p.m.
A damaging tornadic Supercell tracked about 80 miles from Duncan in Stephens County to Stonewall in eastern Pontotoc County Wednesday night. Our own Doug Drace reported golfball hail from the storm in western Garvin County before the tornado formed..and saw it on the ground during a lightning flash at about 9p.. near Joy, OK.
Considerable damage was reported from the twister in Joy (Murray County).
The were also widespread reports of heavy rainfall, intense lightning, and hail to golfball size with this storm.
Meanwhile, other portions of Texoma received not so much as a drop of rain.
Such is the nature of severe storm formation and forecasting. For me, I'm glad it wasn't any worse...it easily could have been.
UPDATE: Wed 19 May 2010 / 1:36p.m.
Texoma is in a moderate to high risk area through Thursday morning (map above).
Huge hail is possible along with a significant tornado threat through late tonight.
Increasing wind shear and lift provided by upper low are part of a new severe threat taking shape mid-week.
Mon 17 May 2010 / 6pm
A turbulent late spring pattern continues as we move deeper into May. The Storm Prediction Center (SPC) says there could be a “significant severe” scenario late Wednesday afternoon through the overnight hours, mainly west of I-35.
This is somewhat similar to the conditions preceding the major tornado outbreak of May 10:
1) Increasing low and mid-level wind shear by Wednesday morning (crossing of green and blue arrows)
2) Deep moisture source from the Gulf (green stream)
3) Well defined upper wave with jet stream support (big blue “L”)
Two factors that appear to be in question (compared to last week) are the timing of the upper wave’s passage, and the position of a surface dry line.
During last week’s event, the dry line punched well to the east and acted as a focusing point for storm growth, which was explosive. They began to fire along it by 4pm around Wichita Falls and Lawton. Racing along at 50-60mph, it didn’t take them long to get into Texoma from their starting point, and quickly become tornadic Supercells.
This time, the dry line will probably be about 100 miles further west, and steering winds will be slower. This means storms will probably arrive in Texoma after sunset, when the air is becoming a little more stable.
Secondly, if the upper wave comes in overnight this will also deprive the system of maximum lift; if it tracks a bit further north this would also lower the risk.
Despite these uncertainties, it seems that portions of Oklahoma and Texas will get some severe storms Wednesday into Thursday.
So I’m not saying we’ll have a repeat of last week, but tornado-producing weather is a possibility for mid-week. Right now, the highest risk seems to be just to our west.
I’ll keep you posted with daily updates.
Below: Storms drop out of forecast once upper low axis moves to east.
This should happen by Friday morning at the latest.