Air Density Report w/ @Syracuseeee – 7.31.17


In this article I will break down the top teams and players that are affected the most by VMI and ADI today.  Many of you might ask what is VMI and ADI is so below I have written a brief description of what they mean and how they affect baseball games.

Air Density Report w/ Cuse

Visual Memory Index aka VMI in baseball is used to track how players perform under different air density’s. The easiest way to explain this is that depending on the weather temperature, humidity, or air density the batters swing will be affected.  You might ask yourself how is that possible?  Have you ever tried to swing a bat in the winter compared to a humid summer day?  It’s not the same and VMI tracks each batters muscle memory to various weather conditions.  A batter’s muscle memory takes time to adjust to certain weather conditions.  When taking VMI into effect I avoid teams or players with a number less than -5 which simply can be explained as they haven’t been hitting pitches with the type of movement that they will face on that day.  As far as what’s good for teams or players, I try and target +5 or greater because they will be used to pitches with high movement and their Visual memory will be good.

Air Density Index aka ADI is very simple to explain.  It’s a scale that goes 0-100 and is affected by three things (Elevation, temperature, and Humidity).  The Air Density is important in baseball because it will let you know how much movement the baseball will have in that ballpark on that day.  The higher the ADI the more movement on the pitch.  Typical 60 is the number people use to decide if the pitcher’s movement will be good or bad.  The lower an ADI is from 60 the less movement the pitchers ball will have and the higher it is from 60 will show the increase in the pitcher’s ball movement to the batter’s eye.


Todays Top Pitchers per VMI/ADI

Danny Duffy-  Duffy will be in a great spot to pitch tonight against the Orioles.  The Orioles come into today with the worst VMI on the slate at -4.31 and a ADI of 63.15 which is better than average.  The other thing to consider is Duffy’s exit velocity has been excellent of as late and the Orioles havn’t hit Duffy much (20 for 107).

Oakland Pitcher- As of this morning Sonny Gray is listed but I’m pretty sure he won’t be pitching as teams have asked the Athletics not to pitch him till after the trade deadline.  Regardless of who the pitcher is play them today.  The SF Giants have a team VMI of -5.15 and the ADI listed in Oakland will be 68.51 which is the best on the slate for pitching.  Lets also add it’s a pitchers ballpark, winner winner chicken dinner.


Top Teams to use for hitting per ADI/VMI

  • Seattle Mariners- The Mariners have the best team VMI on the slate at +7.20 and the conditions in Texas will be HOT as usual.  The Mariners have done very well versus LHP this year.  Seattle has already roughed up Haels once this year (5 IP/ 3 ER)


  • KC Royals- The Royals have a nice bump up in Team VMI today at 2.75 and face Mr. Jimenez


  • Tampa Bay Rays- The Rays Team VMI looks very interesting today at 3.78 in an environment that looks below average for pitching tonight. The ADI tonight in Houston will be 60.81 which is still above average but below what we usually get in Houston.  The Rays would be an interesting Contrarian stack with a lot of people on Morton tonight.