1730Z Discussion

A splendid day in Storm Lake with the wind making things feel a tad cooler than the current 81. Last night's rainfall totaled 1.12".

...Severe Weather Outlook...Today...
Latest day 1 outlook has brought down the tornado probabilities and forecast soundings up in ND/MN have QC /quality control/ issues. Recalling from last night what the soundings looked like in Fargo, things looked fairly favorable for tornadoes as there is/was sufficient shear and the cap had eroded by mid-afternoon. Simulated radar was overdoing the thunderstorms that are currently in ND and northern MN; but looks as if the warm front may offer up best chance for tornadic development later this afternoon.

17z subjective analysis placed the warm front in southern ND eastward through MN into northern WI. A deepening low will move into central ND early this afternoon along with the warm front moving northeastward. Dewpoints in the warm sector are in the 60s with a small pocket of 70s east of the Twin Cities. A surface cold front forming in western SD will overtake some of the warm front throughout the day. Currently, western SD is strongly capped with 700mb temps 13/14+ so don't anticipate convection to form until evening. With winds advecting /moving/ in warmer temps at 700mb further to the NE, this should mean convection should be withheld until late afternoon.

Currently, SBCAPE values are around 2500J/kg south of the warm front in SD and southern MN. CIN is fairly strong over the Dakotas, but less so further east into MN. 0-1km shear is fairly impressive with 200m2/s2 /max of 600/ and 0-3km shear values of 300m2/s2 /max of 700/ over northern MN. Supercell and tornadic composite charts impressive over northern MN and SE ND.

The main show should be along the cold front with thunderstorms developing an hour or two before sunset. I was feeling that the warm front may be able to get some thunderstorms going by late afternoon, but there may be too much inhibition to do so. Nonetheless, storms that may form along warm front will do so in SE ND, where there will be a CIN gradient with weak values and better CAPE/shear. These storms may be surface based with possibility for isolated tornadoes.

1744Z/12:44PM