Skip Talbot
EF5
I've seen some pretty goofy hodos, but this is right up there:
The NAM for the past couple runs has been deepening and ejecting a surface low on Saturday over eastern SD/western MN. Low level veering and shear looks very impressive on these solutions. Huge curving hodographs, insane SRH values. Moderate instability south of the warm front, a sub 1000 low, and tornado parameters are spiking pretty high right on the front.
That's the NAM though. Huge differences on the GFS, which is later and weaker with the low.
We've got a serious shot at tornadoes if the NAM is close, but the GFS looks like another lackluster MCS play with weak forcing, shear, and little focus for initiation. I'm more inclined to side with the higher resolution NAM at this time range, even though it's been leading us on the past couple setups. I'm already up in South Dakota, and will hang around just to see if this verifies since I've already made the trip. The NAM solution would just several tornadoes on the warm front, although the upper level support isn't there, so storm mode and maintenance might be a problem. Still, the effective shear is more than enough to maintain supercells near the warm front (>40 knots) and we should have some forcing off the dryline and trailing cold front with an open cap. More meridional flow suggests north moving storms. They might overrun the relatively narrow instability axis fairly quickly unless they can turn right on the warm front, or mature quickly and come off the dryline/cold front further south. The surface pattern isn't too shabby in itself though even with this fairly narrow instability axis. We saw a similar pattern last fall put down the Wayne EF4, close to the low, on the warm front, but that day had more robust UA flow I believe.
The pessimist would say this is the outlier, wishcasting solution, and we're going to have another round of ongoing MCS play.
The NAM for the past couple runs has been deepening and ejecting a surface low on Saturday over eastern SD/western MN. Low level veering and shear looks very impressive on these solutions. Huge curving hodographs, insane SRH values. Moderate instability south of the warm front, a sub 1000 low, and tornado parameters are spiking pretty high right on the front.
That's the NAM though. Huge differences on the GFS, which is later and weaker with the low.
We've got a serious shot at tornadoes if the NAM is close, but the GFS looks like another lackluster MCS play with weak forcing, shear, and little focus for initiation. I'm more inclined to side with the higher resolution NAM at this time range, even though it's been leading us on the past couple setups. I'm already up in South Dakota, and will hang around just to see if this verifies since I've already made the trip. The NAM solution would just several tornadoes on the warm front, although the upper level support isn't there, so storm mode and maintenance might be a problem. Still, the effective shear is more than enough to maintain supercells near the warm front (>40 knots) and we should have some forcing off the dryline and trailing cold front with an open cap. More meridional flow suggests north moving storms. They might overrun the relatively narrow instability axis fairly quickly unless they can turn right on the warm front, or mature quickly and come off the dryline/cold front further south. The surface pattern isn't too shabby in itself though even with this fairly narrow instability axis. We saw a similar pattern last fall put down the Wayne EF4, close to the low, on the warm front, but that day had more robust UA flow I believe.
The pessimist would say this is the outlier, wishcasting solution, and we're going to have another round of ongoing MCS play.
