Weather Monitoring Options
Jon Clements
MSU Extension Berrien County Horticulture and Marketing Agent
June 1999
Knowing weather conditions in your orchard is an important component of practicing IPM because many disease and insect life cycles are intimately tied to temperature (degree-days), precipitation, and leaf wetness. In addition, weather has a profound impact on many of your day-to-day orchard management decisions, particularly when it comes to spraying.
Clearly, an on-site weather station is the best for getting a handle on potential disease and insect pest conditions in your orchard. Recently, better and more cost-effective options for monitoring on-farm weather have become available. For forecasts, however, you also need access to other weather information sources. Here is a quick review of the latest weather monitoring options you ought to consider:
‘Traditional’ Weather Forecasts/Current Conditions – these include newspaper, radio, television, etc. Unfortunately, lots of variability exists in these products—you probably have your own favorite that is familiar and has proven reliable over the years. If you have cable or a satellite dish, ‘The Weather Channel’ is the most frequently updated, and arguably the most accurate source of current conditions and forecasts.
Weather Radio – the National Weather Service (NWS) broadcasts frequently updated weather information that can only be received via the special ‘Weather Radio’ broadcast band. These originate from several National Weather Service offices throughout Michigan (Grand Rapids, Detroit, Traverse City) and the rest of the United States. Weather Radio is broadcast at a frequency of 162.400 or 162.550 Mhz. Therefore, you need to invest in a special weather radio to receive it. Weather Radio has the added benefit of audible warnings/alerts when severe weather is imminent.
Internet – the Internet has become a good resource for up-to-date weather information. Numerous World Wide Web sites prominently feature weather information. Noteworthy sites include ‘The Weather Channel’ (www.weather.com); ‘Accuweather’ (www.accuweather.com); the National Weather Service (www.nws.noaa.gov) and the MSU Agricultural Weather Office (www.agweather.geo.msu.edu).
Of particular note are Accuweather and the MSU Agricultural Weather Office. Accuweather offers Personal Accuweather, which for a subscription fee, customizes weather observations and forecasts for a location specified by zip code. A thirty day free trial subscription is available.
The MSU Agricultural Weather Office posts frequently updated observational weather data and forecasts for Michigan based on National Weather Service information, and it’s own ground-collected weather data, which is part of the Michigan Automated Weather Network (MAWN). As a part of the GREEEN initiative, MAWN "will eventually provide high quality, detailed weather data as input into Integrated Pest Management (IPM) and other weather-related decision-making activities as well as updated meteorological and climatological information available via the Internet." The MSU Agricultural Weather Office site also has useful links to National Weather Service 60-hour detailed and specific minimum temperature forecasts.
Commercial Weather Services – Perhaps the commercial weather service growers are most familiar with is the ‘Data Transmission Network’ (DTN, www.dtn.com). They offer frequently updated satellite weather images and forecasts, as well as commodity information, for a monthly or annual fee.
Another commercial weather service is ‘SkyBit’ (www.skybit.com). SkyBit offers detailed (hourly) and site-specific (down to one meter square, based on latitude/longitude and elevation) weather observations and forecasts. SkyBit has also taken basic weather data and applied the value-added approach to products that are of particular interest to fruit growers, including spraying ‘keys’ and apple disease/insect predictions. SkyBit has a monthly subscription fee, and they also offer a free trial period. Their products can be delivered via fax or e-mail.
On-Site Weather Stations – Growers have traditionally been reluctant to purchase farm-based weather stations because they were expensive and difficult to calibrate and maintain. Now, however, there are some inexpensive and accurate weather monitoring stations available. Often, they are paired with a personal computer application that helps visualize the collected weather data and uses it for pest and disease models that aid decision-making.
For example, Spectrum Technologies (www.specmeters.com) sells a ‘Mini-Weather Station’ that records temperature, relative humidity, leaf wetness, and precipitation. Coupled with a laptop computer and the appropriate software, weather data can be graphed, and scab or fireblight infection models can be run.
Davis Instruments (www.davisnet.com) is another producer of moderately priced agricultural weather stations that are reliable, and simple to set-up and use. Their weather equipment also interfaces with a computer application that allows easy manipulation and graphical viewing of collected weather data.
Although powerless to change the weather, when armed with one or several of these weather monitoring options, you should be able to get a pretty good handle on the weather conditions on your farm that impact insect and disease pressure. Without good weather data, however, your pest management program takes on more of a ‘shot-in-the-dark’ approach. Hence, weather monitoring is implicit in practicing good IPM.