Bill Schintler
EF4
Chase target for today, May 17
Chase target:
McCook, NE.
Timing:
4 PM, CDT.
Storm type:
Isolated high-based storms with hail to golf-ball size and winds to 80mph.
Discussion:
300mb analysis showed negatively-tilted trough over ID with zone of divergence spreading towards ERN CO/WY and WRN NE. Two shortwaves lifting through the SWRLY upper flow were evident in 700mb analysis and WV imagery. The first was lifting through SD while an upstream wave was diving through CO and WY. A 50kt LLJ was pulling 10C dewpoints N into KS/NE. Moisture was fairly shallow – about 50mb deep – as noted at both LBF and DDC 12Z soundings. DDC indicated a large hodograph loop below 700mb, although this zone of high helicities was lifting away from the target area. Last night, WWA resulted in an MCS as well as widespread precipitation in SD and MN, which is ongoing ATTM. Skies are mostly clear in NE and KS, with some CI spreading into the WRN areas. SFC dewpoints were meager, generally in the mid-50’s throughout the region.
Today,
Storms will fire along the surface trough which will be lifting E out of CO. The area will be strongly capped through the mid-afternoon, with 700mb temps AOA 10C, however rapid mid-level cooling will commence with the approach of the S/WV with 6hr temperature drops of 5C in the target area. Expect ample instability, with MLCAPE’s AOA 1500J/kg and LI’s around -6C. Straight hodographs along with deep layer shear of around 40kts will support decent storm organization.
- bill
Chase target:
McCook, NE.
Timing:
4 PM, CDT.
Storm type:
Isolated high-based storms with hail to golf-ball size and winds to 80mph.
Discussion:
300mb analysis showed negatively-tilted trough over ID with zone of divergence spreading towards ERN CO/WY and WRN NE. Two shortwaves lifting through the SWRLY upper flow were evident in 700mb analysis and WV imagery. The first was lifting through SD while an upstream wave was diving through CO and WY. A 50kt LLJ was pulling 10C dewpoints N into KS/NE. Moisture was fairly shallow – about 50mb deep – as noted at both LBF and DDC 12Z soundings. DDC indicated a large hodograph loop below 700mb, although this zone of high helicities was lifting away from the target area. Last night, WWA resulted in an MCS as well as widespread precipitation in SD and MN, which is ongoing ATTM. Skies are mostly clear in NE and KS, with some CI spreading into the WRN areas. SFC dewpoints were meager, generally in the mid-50’s throughout the region.
Today,
Storms will fire along the surface trough which will be lifting E out of CO. The area will be strongly capped through the mid-afternoon, with 700mb temps AOA 10C, however rapid mid-level cooling will commence with the approach of the S/WV with 6hr temperature drops of 5C in the target area. Expect ample instability, with MLCAPE’s AOA 1500J/kg and LI’s around -6C. Straight hodographs along with deep layer shear of around 40kts will support decent storm organization.
- bill
