Chris Hovanic
EF0
0z NAM has rolled in this evening and depicts an interesting situation for northern MO, southern/central IA, and western IL on Sunday...
Large MCS should evolve late Saturday night into Sunday morning across eastern NE and western IA, as several weak shortwaves emanating from the large subtropical moisture plume through Mexico and Texas interact with an area of significant moisture convergence along the nose of a 45-50 kt low-level jet. This convection should organize and traverse around the edge of an upper-level ridge positioned across the Gulf Coast states, moving into northern IL by early afternoon.
0z NAM depicts a fairly significant outflow boundary that will either be left behind the departing MCS or perhaps outline its southern extent. A moderately to very unstable airmass should develop along the southern and western perhipery of the OFB as the day progresses thanks to breaks in the clouds and a very deep moisture profile. MLCAPEs of 1500-2000 J/KG should be attainable given the depth of the moisture.
Scattered thunderstorms should develop in the vicinity of the OFB, likely across S IA and N MO by mid-late afternoon, perhaps in association with another weak subtropical impulse notching through the area. 500mb flow increases to 30-35 kts as this impulse swings through, and given 10-15 kt SE'ly flow at the surface, should result in enough deep layer shear for supercells, or at least well organized multicells. Low-level shear will be maximized along the boundary, and could result in a few tornadoes given low LCL heights and the potential for storms to ride the boundary with expected slow SE or ESE storm motions.
Will certainly be keeping a close eye on this potential sleeper setup given that I'll be in Mercer, MO for a buddy's birthday party on Saturday night, and have the day off on Sunday.
Large MCS should evolve late Saturday night into Sunday morning across eastern NE and western IA, as several weak shortwaves emanating from the large subtropical moisture plume through Mexico and Texas interact with an area of significant moisture convergence along the nose of a 45-50 kt low-level jet. This convection should organize and traverse around the edge of an upper-level ridge positioned across the Gulf Coast states, moving into northern IL by early afternoon.
0z NAM depicts a fairly significant outflow boundary that will either be left behind the departing MCS or perhaps outline its southern extent. A moderately to very unstable airmass should develop along the southern and western perhipery of the OFB as the day progresses thanks to breaks in the clouds and a very deep moisture profile. MLCAPEs of 1500-2000 J/KG should be attainable given the depth of the moisture.
Scattered thunderstorms should develop in the vicinity of the OFB, likely across S IA and N MO by mid-late afternoon, perhaps in association with another weak subtropical impulse notching through the area. 500mb flow increases to 30-35 kts as this impulse swings through, and given 10-15 kt SE'ly flow at the surface, should result in enough deep layer shear for supercells, or at least well organized multicells. Low-level shear will be maximized along the boundary, and could result in a few tornadoes given low LCL heights and the potential for storms to ride the boundary with expected slow SE or ESE storm motions.
Will certainly be keeping a close eye on this potential sleeper setup given that I'll be in Mercer, MO for a buddy's birthday party on Saturday night, and have the day off on Sunday.
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