Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0317 AM CDT Fri Apr 07 2017 Valid 101200Z - 151200Z ...DISCUSSION... Model consensus is that a relative low amplitude and progressive regime will characterize the upper pattern days 4-5, followed by gradual amplification but with increasing model spreads days 6-8. Monday (day 4) - A cold front will settle south into north and west-central TX during the day. Rich low-level moisture with upper 60s dewpoints will reside in warm sector where the atmosphere will become moderately unstable. Low-level winds are forecast to be relatively weak/modest which may limit frontal convergence to some degree, but winds aloft will undergo a modest increase with the approach of a southern-stream upper trough. Storms are expected to develop in the frontal zone during the afternoon and propagate into the unstable warm sector. Steep lapse rates, moderate instability and modest deep shear will support a threat for a few instances of large hail and damaging wind with the stronger storms. Some severe threat may also exist from the western OH Valley into the Great Lakes. Stronger winds aloft will reside near a northeast-southwest oriented cold front located downstream from an upper trough forecast to be near the middle-upper MS Valley. While instability should remain modest, storms developing in this region will be embedded within strong unidirectional shear and may have potential to organize and pose a risk for large hail and locally strong wind gusts. Tuesday (day 5) - A marginal risk for severe storms might exist over the OH Valley in association with the progressive shortwave trough. However, insufficient instability will likely preclude a more substantial severe threat. Other storms along and south of frontal zone across TX and into the lower MS valley could also pose at least a marginal severe risk. Beyond day 6 predictability or potential appears too low at this time.Read more
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