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Umpire Analysis: Factoring In Weather

Patrick Kaiser

Patrick Kaiser has been competing in Daily Fantasy Sports since it originated in 2007, under the username Kaiseroll13. He is one of the pioneering players in the industry and reached top overall player status as well.

April showers bring...a lot of unruly Daily Fantasy owners. One of the harshest lessons to new Daily Fantasy Baseball players is the (sometimes) adverse effect of weather. This is especially true for those that transitioned from NBA, where it takes an elevator fire in Mexico or an asbestos scare in Madison Square Garden (2010) to postpone a game. Hopefully you weren't victimized this past week after eight games were rained out in the last six days (and a whopping four on Wednesday!). Brighter days are ahead, and what feels like a fickle beast to overcome can actually be a competitive advantage for users that learn how to predict and react appropriately.

I can still remember the initial pain of Mother Nature hanging some zeroes in my lineups six years ago. After a couple days of cooling off to the apparent unpredictability of this MLB crapshoot I came to terms with what had to be done to push forward. At the time, there were zero websites dedicated to Daily Fantasy news & info, so I went straight to and checked each city in which games were played on a given day. The benefit to accurate weather reaction is twofold: both avoiding players at high risk to get rained out and also to gauge if there is an increased edge to playing FanDuel based on opponents selecting players that could be postponed.

A key mistake people make is merely looking at the overall % chance of precipitation. Many oddsmakers and MLB-related sites use a single percentage as the barometer for rain effect on a game, but trusting that will put you at a disadvantage. To say that there is a 75% chance of rain today for Chicago, or even 75% chance at gametime doesn't tell us the actual risk of that game not being played. The most prudent move is to look further into the games that appear to have any chance of rain moving through, usually 40% or higher is worth knowing more information. Personally, I use hour-by-hour forecasts as the best informant for weather risk.

The first thing to look for is steady rain forecasted before, during, and after a scheduled game. It's amazing how much the rain can update throughout the afternoon leading into FanDuel's contests locking, and we are focused on whether or not there will be a solid 3-hour window to play a full 9 innings. In my experience, if a stadium is predicted for 70%+ rain each hour throughout the day then you can just write it off. The tarps will be on the field for hours before the game and likely an announcement can be made in the afternoon that the game will be rescheduled to help prevent the fans from bothering with travel to the park.

Anything outside of the previous rain forecast scenario is where it gets tricky. At noon on a day of a 6 p.m. game it may say that solely for the 2-3 hours of the game that 70+% showers are predicted. More often than not, as the gametime approaches the clarity of the weather sharpens and a window for the game will seemingly appear out of nowhere. The last thing you want to do is discount players with a ripe matchup (and/or severely underpriced) because of rain risk that turns out to be much lower than you thought. For any games that show 50%+ at some point during the gametime I would recommend keeping that hour-by-hour forecast open and refreshed every half hour or so as the gametime nears.

Scattered showers almost never result in an effect on a game. So, even if the forecast is showing 80% scattered showers during a game, the chances of those rainclouds happening upon the exact location of the ballpark for even an hour are unlikely to say the least.

It is also worth noting that intradivisonal games are more likely to be postponed because the teams face each other many more times throughout the season, allowing for rescheduling to go much smoother. Interleague games offer the opposite end of the spectrum as these matchups are for a single series, meaning the umpires will hold out longer in any hopes of getting the game in the books.

So now that we know the process to assess the risk of a rainout, how do we apply it to lineups and player selection? First, rain risk affects pitchers more than hitters. A game can be played through some light rain (and sometimes heavy leading into a delay), but I wouldn't trust a pitcher's grip and command as much in these conditions. I've never heard a pitcher say they prefer to throw in the rain. The other aspect to consider with pitchers is the effect of any rain delay. Hitters can go sit in the clubhouse and come out ready to play after however long of a delay, but pitchers run the risk of getting yanked if their arm was already warm before the stoppage. The specific risk can vary from player to player based on their injury history and current physical shape. An hour delay can be enough to send any given starter to the bench when play resumes, and that is not a chance you want to take in your lineups if heavy rain is expected early or in the middle of a game.

As for hitter selection, you can afford to be a little more liberal as long as you feel good about there being 3 hours of baseball able to be played in a 5-6 hour window starting at gametime. Most games start at 6 or 7 p.m. so a 2-3 hour delay still has the game finishing around midnight, with the hitters getting their full 4-5 at bats. Once in awhile a team may play it safe with an injury-riddled player (mostly outfielders) and rest them due to field conditions but that is extremely rare.

If after all of the correct research, debate and internal dialogue you still aren't sure about whether to pick players from a weather-affected game? Err on the side of caution and mental health and seek out alternatives from safer environments. An automatic zero is one of the worst feelings in all of Daily Fantasy and you will forgive yourself sooner for picking players that will surely see their full IP and AB's than if you allow Mother Nature to manhandle your FanDuel MLB experience.

Bonus Round: Here's a ranking of my Top 10 offenses to target Friday based on matchups and recent performance.

Top Tier
Rays at Vidal Nuno
Orioles at Ricky Nolasco
Athletics at Clay Buchholz

Middle Tier
Red Sox vs. Dan Straily
Rockies vs. Zack Wheeler
Twins vs. Ubaldo Jimenez
Rangers at Hector Santiago
Mets at Jorge De La Rosa
Angels vs. Colby Lewis
Mariners at Brad Peacock
The author(s) of this article may play in daily fantasy contests including – but not limited to – games that they have provided recommendations or advice on in this article. In the course of playing in these games using their personal accounts, it's possible that they will use players in their lineups or other strategies that differ from the recommendations they have provided above. The recommendations in this article do not necessarily reflect the views of RotoWire.