Time to get today's thread started.
I thought the parameters yesterday looked incredible. Those numbers are already being surpassed today! Anywhere at and south of the OFB being laid by the current MCS tracking across N MS/N AL/S TN and east of the dryline, which currently sits in far western LA, looks to be under a high risk of significant severe weather. Sig tor is already above 5 over most of LA, SE AR, S MS, S AL, and maxes out at 12 in LA! EHI is very large in the same area, with 0-3 km EHI values maxing out at 15 in SE LA, and 0-1km EHI values maxing at 12 in S LA. Effective shear is just as high as it was yesterday, with a noticeable gradient southward towards the coast. That will probably limit the sigifnicant severe threat down towards New Orleans if shear does not increase there. However, low-level shear is extreme, with 30 - 60 kts region wide (60 kts area is over the ongoing MCS). SBCAPE is in the 3000 - 4000 J/kg range across much of LA, S MS, S AL, and 0-3 km CAPE is currently upwards of 125 J/kg in LA, but is minimal east of there (I assume it is building eastward). Given current visible satellite imagery trends, I would say the atmosphere is not quite yet ready to go over much of S/E LA and into MS and AL, but clearing is occurring from the west just ahead of the dryline and rapid destabilization is underway there as well.
ADD: Unfortunately, the 13Z HRRR shows a supercell going right though Jackson at 19Z and the 14Z run shows a storm going just south of town early in the afternoon. Given the amount of severe weather central Mississippi has had in the last 12 months, if I lived there I would be quite nervous today.
I thought the parameters yesterday looked incredible. Those numbers are already being surpassed today! Anywhere at and south of the OFB being laid by the current MCS tracking across N MS/N AL/S TN and east of the dryline, which currently sits in far western LA, looks to be under a high risk of significant severe weather. Sig tor is already above 5 over most of LA, SE AR, S MS, S AL, and maxes out at 12 in LA! EHI is very large in the same area, with 0-3 km EHI values maxing out at 15 in SE LA, and 0-1km EHI values maxing at 12 in S LA. Effective shear is just as high as it was yesterday, with a noticeable gradient southward towards the coast. That will probably limit the sigifnicant severe threat down towards New Orleans if shear does not increase there. However, low-level shear is extreme, with 30 - 60 kts region wide (60 kts area is over the ongoing MCS). SBCAPE is in the 3000 - 4000 J/kg range across much of LA, S MS, S AL, and 0-3 km CAPE is currently upwards of 125 J/kg in LA, but is minimal east of there (I assume it is building eastward). Given current visible satellite imagery trends, I would say the atmosphere is not quite yet ready to go over much of S/E LA and into MS and AL, but clearing is occurring from the west just ahead of the dryline and rapid destabilization is underway there as well.
ADD: Unfortunately, the 13Z HRRR shows a supercell going right though Jackson at 19Z and the 14Z run shows a storm going just south of town early in the afternoon. Given the amount of severe weather central Mississippi has had in the last 12 months, if I lived there I would be quite nervous today.
Last edited by a moderator: