Plains forecast update for April 19
The trend of great-looking systems in the medium-to-long ranges tanking as they come into short-range focus continues. Today's setup has ended up in western-central Iowa rather than in the Plains, with a too-narrow window for tornadoes for the 9+ hour drive. Meanwhile, Friday's setup has devolved into an ill-timed passsage of the upper wave, promoting early-day convection followed by a cold front sweeping across the warm sector in Oklahoma. It's not a complete wash, but definitely not the clear-cut chaseworthy opportunity it had been protrayed earlier this week. It has mostly dropped off of my radar for a trip barring a last-minute recovery.
The next couple of systems shown following for the middle of next week and beyond hold some potential, as general western US troughing and increasingly deep Plains moisture is shown. But again, given the poor performance of long-range forecasts this month, I'm not very confident on anything panning out at this point.
The following table charts the probabilities for a Plains chase expedition taking place for the date ranges shown:
|2017 Plains Chase Expeditions - Probabilities as of April 19|