Useful Links To Past Weather
The NCEI archives all National Weather Service records for the United States. Much of the data can be accessed online, free of charge. Certification services are available for some data sets.
The NCEI also manages 6 regional climate centers that provide data and certification services.
I include a link to the Weather Underground's website because I am aware that many already visit it for a preliminary look at past conditions. It is fast and easy to access that data, however I must strongly caution that unless you are familiar with some of the idiosyncracies related to automated weather stations (most stations are fully automated) you may come away with a misleading impression of what occurred. For example, private weather stations linked on The Weather Underground website frequently do not have all of their equipment properly situated to record accurate atmospheric conditions. For example, anemometers should be located at a height of 10 meters and there should not be any trees or buildings nearby blocking or affecting the airflow. This is rarely the case with many private weather stations that you will find online, so in general, I would not trust most wind-related data. Some private stations do not have their thermometer properly screened from the sun, so at certain times of day the temperature reading is not accurate. Even the official ASOS stations managed by the National Weather Service have difficulty sometimes determining what type of precipitation is falling or whether or not it is snowing out. The most accurate way to determine past conditions is by interpolating data from several nearby data sources.
I have specialized in determining past weather conditions for attorneys, insurance companies, and engineers for over 25 years. I can perform an assessment for any U.S. location. Most situations require the interpolation of data from several different sources. If you need to determine what weather conditions existed at a specific time and place in the past, contact me. Initial consultations are free. I would be happy to give you a general idea of what it was like. If you have a weather related legal case or insurance claim, I can be retained to perform a detailed, site-specific analysis of the situation. The results can be conveyed to you via verbal or written reports, or in any way you prefer. Written reports include copies of the data that I used in the analysis. I will back up my findings in court, if necessary, and am available for deposition testimony prior to that. I can get you data sets that are government-certified with a ribbon and seal if you would like to present them in court, as evidence. I have testified as an expert witness in depositions and trials over 100 times.