MTC TURF NEWS: Brad Jakubowski, Assistant Teaching Professor, Center for Turfgrass Science, Penn State University

Keeping an eye on the weather is something professional turfgrass managers have ingrained into our systems. Can I mow today? We check our phones for the most recent forecast. Should I spray today? We monitor dewpoints, humidity and temperatures. Will I pull the tarp prior to today’s game? We study the weather radar. There is a tremendous amount of weather information out there and nearly all of us have some form of a weather app on our phones, or a link to our favorite weather website, to help us make day-to-day management decisions. Let’s take a journey, to see what is out there and what information will help us make the best weather-based decisions possible.

Which app is the best?

Honestly, there is no one best app. It is important to find an app or a number of apps that provide you the most reliable and quickly available information. Basic Information that is important to have available with the least number of clicks would be: High and Low Temperatures (including overnight lows), Dewpoint, Relative Humidity, and Short-Term Weather forecasts. Intermediate information includes: Radar (Base and Composite Reflectivity), Satellite Imagery, and Severe Weather (especially lightning). Advanced information would be: Echo Tops, Vertically Integrated Liquid, Digital Storm Accumulation and Forecast Discussion.

Basic Information

When looking for basic information, it is best to have most or all important data on the first screen, or within one or two clicks from the first screen. That is often a good way to judge how well your app will benefit you over time. As an example, The National Weather Service includes much of the basic data (Figure 1). At a glance, you can get a good idea of what is happening now and what will happen in the immediate future. High and low temperatures provide a quick mental image of how the day (and night) may influence your maintenance plans. Winds, dewpoint and relative humidity provide a quick insight on irrigation requirements, disease potential, and infield skin management requirements.

It is beneficial to see both relative humidity and dewpoint together. Viewing only either limits your view of the big picture. For example, a relative humidity of 95% with dewpoints near 70 degrees indicate that less time may be spent scouting for wilt and instead used scouting for diseases. The same relative humidity with dewpoints under 30 may indicate a majority of the day may be dedicated for scouting wilt or watering an infield skin.

The Hourly Forecast – The Turf Manager’s Secret Weapon!

The Hourly Forecast on Weather.gov (Figure 2) is the turf manager’s secret weapon. In one image, a turf manager can make plans for multiple issues and tasks. For Example, The Heat Index: potential high heat indexes aids in planning for employee safety; Temperature and Dewpoint: Matched high overnight dewpoints and temperatures means extended leaf wetness and high disease potential. They also indicate heavy dew until at least 8am, which may require a syringe cycle to limit mower clumping, or to make sure greens are whipped post-cut; Wind Speed and Direction (Surface Wind): predicted light southerly winds meaning even higher probability for disease potential and dew, as well as for good spraying conditions in the early morning, but gusts in the teens starting around 11am; Relative Humidity: indicates conditions will be wet early, but dry quickly throughout the day; Sky Cover: indicates it will be partly cloudy throughout the day providing some relief, while Precipitation Potential indicate a 50% chance of rain throughout the day.

Intermediate Information

When making game-time decisions such as tarp pulls, or field evacuations, due to severe weather, radar becomes an important tool.