Bill Schintler
EF4
Chase Target for Tuesday, May 27
Blackwell, OK.
Timing and storm mode:
Storm initiation will be 2 PM CDT. A few supercells will be possible early in storm evolution, with a trend towards a multicell or linear storm complex by late afternoon.
Synopsis:
The WRN CONUS trough will weaken and while slowly retrograding over the next 24 hours while broad, weak anticyclonic flow develops over the SRN plains. Widespread, ongoing convection over KS has worked over the air mass to the extent that recovery necessary for SFC-based convection is unlikely by tomorrow afternoon. Further S, area soundings indicated a moisture layer nearly 200mb deep over OK with SFC dewpoints AOA 70F. At 00Z, a CF bisected KS from SW to NE, and this feature will continue to slowly push S.
Discussion:
FCST is difficult due to uncertain evolution of ongoing convection in SRN KS and WRN OK. Resulting boundaries will determine the location and evolution of tomorrow’s convection in an environment of weak synoptic features. Current reasoning is that the MCS over WRN OK will continue to track slowly to the S into a strengthening LLJ until weakening after 06Z. Early in the period tomorrow, a large MCS will be ongoing in NERN OK, and this will push an OFB S to about a Stillwater to Tulsa line in ERN OK by 18Z. Directional shear should be enhanced along and N of this boundary as 25kt WSWRLY LLJ overspreads ERLY SFC flow. Strong instability will develop with steep mid-level lapse rates over a very moist BL. Wind fields will be weak, however a 30kt mid-level jet will surge through SRN KS, with NRN OK on the SRN periphery the stronger flow. The most likely location for storm initiation will be along the intersection of the OFB and an advancing CF, where the SFC flow should locally back.
- bill
www.twistertoursusa.com
9:20 PM CDT, 05/26/08
Blackwell, OK.
Timing and storm mode:
Storm initiation will be 2 PM CDT. A few supercells will be possible early in storm evolution, with a trend towards a multicell or linear storm complex by late afternoon.
Synopsis:
The WRN CONUS trough will weaken and while slowly retrograding over the next 24 hours while broad, weak anticyclonic flow develops over the SRN plains. Widespread, ongoing convection over KS has worked over the air mass to the extent that recovery necessary for SFC-based convection is unlikely by tomorrow afternoon. Further S, area soundings indicated a moisture layer nearly 200mb deep over OK with SFC dewpoints AOA 70F. At 00Z, a CF bisected KS from SW to NE, and this feature will continue to slowly push S.
Discussion:
FCST is difficult due to uncertain evolution of ongoing convection in SRN KS and WRN OK. Resulting boundaries will determine the location and evolution of tomorrow’s convection in an environment of weak synoptic features. Current reasoning is that the MCS over WRN OK will continue to track slowly to the S into a strengthening LLJ until weakening after 06Z. Early in the period tomorrow, a large MCS will be ongoing in NERN OK, and this will push an OFB S to about a Stillwater to Tulsa line in ERN OK by 18Z. Directional shear should be enhanced along and N of this boundary as 25kt WSWRLY LLJ overspreads ERLY SFC flow. Strong instability will develop with steep mid-level lapse rates over a very moist BL. Wind fields will be weak, however a 30kt mid-level jet will surge through SRN KS, with NRN OK on the SRN periphery the stronger flow. The most likely location for storm initiation will be along the intersection of the OFB and an advancing CF, where the SFC flow should locally back.
- bill
www.twistertoursusa.com
9:20 PM CDT, 05/26/08
