Royce Sheibal
EF3
12Z Nam just came out and I couldn't believe what I saw, a very respectable 0Z sounding for Nebraska City. SPC has a slight, but it sounds like that might get upgraded tomorrow based on the location of the MCS that forms tonight. The SPC's ensemble puts a giant bulls-eye between Omaha and Topeka, moving into NW Missouri between 21Z and 03Z Saturday. Forecast STP's are in the 6-8 range, and SCP's up to 25 or 30? 0-3's SRH in the 400 range, 4-5k Cape possible (if clearing occurs). Td's near 80 and a cap that it forecasts to break near the triple point and along the warm front? Yes plz.
Other Factors to consider: Very solid Theta-E advection is forecast into the area. Moisture convergence along the warm front is looking good. High Res models pull the MCS out of the area by 9am, but will cloud cover clear? Trend this year (due to insanely high local humidity I'm guessing) is no. That being said, we've got solid mid level and upper level support for this system, which may help push the MCS out of the way faster. DPVA is forecast in the region, pretty uncommon this time of year. This isn't exactly a spring-type setup, but rather more likely a fall type setup were the triple point (and the area of best vorticity) is likely the spot were supercells will focus, meanwhile multi-cells will be prevalent further form the triple point. Yesterday (8/6/15) there were several possible tornadic supercells in SD/MN in a similar position close to the vort max.
NAM 4k and GFS both push the low a bit further east, meaning that NW Mo and SW IA would have the best chances, but both of those models have been far too fast this year. For now I'll go with good old NAM, which pushes the MCS up further north than most models (likely why it predicts better clearing and cape as well).
Target: Lincoln Nebraska 21Z (With possible routes East on HWY2 or South on 77). Storms seem to be going earlier than later vs the models recently. That being said, NAM 4k doesn't breakout storms with any decent updraft until 03z, but I haven't been able to trust NAM 4k at all this year. If it's a blue sky bust, I blame the models for getting me all excited. If it's a no-cape rain-out, I blame El Nino. And sadly, my driver is busy Saturday, so I'll be armchair chasing.
Other Factors to consider: Very solid Theta-E advection is forecast into the area. Moisture convergence along the warm front is looking good. High Res models pull the MCS out of the area by 9am, but will cloud cover clear? Trend this year (due to insanely high local humidity I'm guessing) is no. That being said, we've got solid mid level and upper level support for this system, which may help push the MCS out of the way faster. DPVA is forecast in the region, pretty uncommon this time of year. This isn't exactly a spring-type setup, but rather more likely a fall type setup were the triple point (and the area of best vorticity) is likely the spot were supercells will focus, meanwhile multi-cells will be prevalent further form the triple point. Yesterday (8/6/15) there were several possible tornadic supercells in SD/MN in a similar position close to the vort max.
NAM 4k and GFS both push the low a bit further east, meaning that NW Mo and SW IA would have the best chances, but both of those models have been far too fast this year. For now I'll go with good old NAM, which pushes the MCS up further north than most models (likely why it predicts better clearing and cape as well).
Target: Lincoln Nebraska 21Z (With possible routes East on HWY2 or South on 77). Storms seem to be going earlier than later vs the models recently. That being said, NAM 4k doesn't breakout storms with any decent updraft until 03z, but I haven't been able to trust NAM 4k at all this year. If it's a blue sky bust, I blame the models for getting me all excited. If it's a no-cape rain-out, I blame El Nino. And sadly, my driver is busy Saturday, so I'll be armchair chasing.
