LEGAL, INSURANCE, CERTIFICATION
What is "certified" data?
Most states require all records that are to be submitted as evidence in a court of law to be authenticated in some way, typically called certification. There are several types of certification available. The MRCC can certify copies of climate records archived at the MRCC. As an archiving facility, the only fact the MRCC can attest to is that exact duplicates of climatic records on file at this center have been provided to those that requested such data. The National Climatic Data Center, the official United States archive for climatic records, can provide two types of certification. For more information on certification, please check our Certification page.
What can you testify to in court (and where can you testify)?
Generally, it is not necessary for us to appear in court to testify about the data we supply. The certification we provide serves the purpose of authenticating data. If we are subpoenaed to testify, we appear only as a Friend of the Court, and can testify only that the data come from our archives. We cannot testify as to the accuracy or appropriateness of the data and cannot appear as an "expert witness". For more information see the NOAA document "Weather Records in Private Litigation" (http://lwf.ncdc.noaa.gov/oa/documentlibrary/pdf/eis/C-1.pdf ). If expert testimony is needed, the services of a forensic meteorologist should be retained. The American Meteorological Society [http://www.ametsoc.org/AMS/ ] and the National Weather Association [www.nwas.org/] maintain listings of consulting meteorologists.
An inspector said that I have had hail damage to the roof of my home. I've lived in my house since 1995. Can you tell me all of the dates that hail was reported in my area?
That depends. First of all, hail is typically a very localized phenomenon. It may hail in one location, and a half mile away no hail may be observed. Because it can occur in a relatively small area, not all hail that falls is observed or reported. One of the criteria for a severe thunderstorm is observed hail ¾ inch or more in diameter, so if severe storms have occurred at your location there may be a record of hail if it occurred. These reports include the size of the hail, location where it occurred, and time it occurred.
For events less than three months old, check the preliminary daily storm reports on the Storm Prediction Center web site [www.spc.noaa.gov].
For events greater than three months old, check the on-line Storm Data [http://lwf.ncdc.noaa.gov/oa/climate/severeweather/extremes.html]
database maintained by the National Climatic Data Center
The only source of hail data that the MRCC can provide are copies of the pertinent storm event pages found in the publication Storm Data. Storm Data is compiled and published by NCDC. There is about a six-month lag in the publication of the monthly Storm Data publications. The minimum cost for receiving copies of Storm Data pages is $22.00. Certified copies of Storm Data must be requested through NCDC. If you have questions or need assistance in acquiring storm information, please contact our Service Climatologists.
Lightning struck my house and damaged my TV and personal computer. The insurance company said that I need to provide documentation in order to process the claim. Do you have such information?
No, the only source for lightning data is Global Atmospherics, Inc. [www.globalatmospherics.com] . They operate the National Lightning Detection Network, and provide custom reports on lightning strikes, and can locate strikes usually to within 500 meters. The MRCC may be able to tell you whether or not a thunderstorm was reported in your area, depending on the availability nearby reporting stations.
I had wind damage to my roof during a recent thunderstorm, and the insurance company needs documentation of the wind speed before it will process the claim. Can you tell me what the wind gusts were during the storm?
Wind speed can vary greatly over short distances, and is affected by such things as trees, buildings, and other obstacles. Most wind speed and direction data is obtained from airport observations sites. Usually these have an unobstructed exposure to the wind and may not accurately represent the wind conditions at, for example, an urban location. If an airport observing station is located near your home, this data may be available and be sufficient evidence. How applicable this data may be to your location depends on your proximity to the observation site. If there is no wind observation site nearby, we would have to rely on the Local Storm Reports gathered by the National Weather Service or the Storm Data publication published by NCDC. Local Storm Reports are listings of storm-related tornado, hail, and wind gust/wind damage events. Wind speeds reported are often estimates and usually not at "official" observing sites. However, these reports may provide evidence that a severe storm occurred in your area.
HOW TO OBTAIN DATA
How do I request data from the MRCC?
There are a number of ways to request data from us. You may call us at (217) 244-8226. Our office hours are from 8:00 - 5:00 (Central Time) Monday through Friday. However, we have a voice mail system that is available 24-hours a day. You may also fax us at (217) 244-0220, or email us at mrcc@isws.illinois.edu.
No matter how you contact us, please leave us your name, telephone number (with area code), and details concerning your data request such as the date, city and state, and the weather data you are interested in (hourly, daily, monthly, temperatures, precipitation, wind speed, etc.).
I need climate data on a monthly basis but I don't want to have to call and order it each month. Is there way to obtain data on a regular basis?
Yes. The Midwestern Applied Climate System (MACS) is a subscription-based service that gives users access to a large variety and quantity of climate data. If your regular data needs can be met by a MACS subscription, this may be the most cost-effective way to obtain your data. Contact one of our Service Climatologists to discuss your needs. If you have data needs that cannot be met by a subscription to MACS, our Service Climatologists will work with you to determine the best means to provide you the data you require.
I want the daily rainfall for a location. Can I just call the observer and get the data?
The observers in the U.S. Cooperative Network are volunteers. We do not provide the names, addresses, or phone numbers of observers. Many observers report their observations each day (near real-time), and this data is available from the MRCC or from the National Weather Service. However, near real-time data has only minimal quality control. Other observers send their information to the local National Weather Service office once each month. All data is sent to the National Climatic Data Center where it is quality controlled.
TYPES OF DATA AVAILABLE
What is the difference between hourly data, daily data, and monthly data?
Hourly data are the values observed each hour, usually at airport stations. Hourly values typically include temperature, dew point temperature, wet-bulb temperature, relative humidity, barometric pressure, and wind speed and direction. Daily data refers to values that represent the character of the weather for a particular day. These usually include maximum temperature, minimum temperature, mean temperature, and total precipitation, but may include other values, such as snowfall. Monthly data refer to values the represent the character of the climate for a specific month and are typically averages or sums. Monthly data may include average maximum and minimum temperatures, average mean temperature, total precipitation, and total snowfall. Daily and monthly values are available for most airport stations as well as cooperative observer stations.
Do you provide sunrise and sunset data? Do you also provide information on the phases of the moon?
No, the U.S. Naval Observatory [http://aa.usno.navy.mil/data] is the official source for these data. They provide this information for free on their web site.
I'm traveling to Minneapolis next week and would like to know what the weather is going to be like. Can you help me with this?
No, the MRCC does not provide weather forecasts, just historical data. Weather forecasts are the responsibility of the National Weather Service [www.nws.noaa.gov]. NWS forecasts and other information can information can be found on the Interactive Weather Information Network [http://iwin.nws.noaa.gov/iwin/graphicsversion/rbigmain.html] web site.
I'm an attorney who has a trial coming up next month. We need to know what the official National Weather Service forecast was for the date of interest, not just the actual weather. Do you provide documentation of past weather forecasts?
No, the MRCC does not have this information available in their archives. Archives of past forecasts are only available from the National Climatic Data Center (NCDC) [www.ncdc.noaa.gov]. They also have past severe weather watches, warnings and advisories available in their archives as well.
ABOUT THE DATA
What does the "T" mean in the precipitation column of the data listing?
The "T" stands for "trace." A trace of precipitation is precipitation that was observed but accumulates to less than .01 inch.
The observe time column in the daily data listing shows MID, AM, or PM. What do these mean?
Most cooperative stations take observations in the early morning or in the late afternoon. These abbreviations indicate at what time the observations are taken. MID stands for midnight, and indicates that the data listed represents the 24 hour period ending at midnight. AM indicates a morning observation, usually 7:00 a.m., but sometimes 8:00 a.m. PM indicates an afternoon observation, usually 4:00 p.m. The data represent the 24 hour period ending at the observation time. This does present some problems when comparing data between two stations with different reporting times, and users need to be aware of these differences. For example, a maximum temperature occurring around 2:00 p.m. will be reported on that same day by the afternoon observer, but on the next day by the morning observer.
FEES
Why do you charge for the data?
We do not charge for the data. Fees are assessed to cover costs of information delivery, including processing, reproduction, and the computer systems necessary to maintain and process the data. For more information on our fees, please see our Climate Data Services/Pricing Policies page on this web site.
What can I get for free?
The MRCC provides generalized climate information at no charge on our web site. The Midwest Climate watch provides temperature and precipitation maps of the Midwest for the current month. These are updated automatically each day. In addition, narrative descriptions of the past week's weather are included. Historical climate summaries are also available for more than 750 Midwestern locations. These summaries include tables and graphs of temperature, precipitation, snowfall, and degree days. There is also an abundance of weather and climate information available on the web. Check our Weather Resources/Links page for access to other interesting weather and climate sites.
