As to what types of forensic weather research can be done—or put another way, what types of weather reconstruction a forensic meteorologist can do—the answer may surprise you: a lot.
But first, a caveat: A lot of weather reconstruction takes more time than in this case. Basically, the sooner you decide you need an expert and tell your expert what you need to know, the better.
The sheer size of our state notwithstanding, we now have decent coverage of automated weather stations, making frequent observations and sending them electronically to the National Weather Service (NWS) switching center, from which they are distributed to interested parties and permanently stored. These weather observations normally include air temperature, dewpoint (from which relatively humidity can be derived), wind direction and speed, cloud cover (height above the ground and extent of coverage), horizontal visibility, and present weather (i.e., rain, snow, fog, mist, thunderstorm, etc.). These observations are made at least hourly.
Even if the location in which you are interested isn’t close to one of the stations, it is often possible to interpolate between several stations with reasonable accuracy. And most of the state is within range of the network of nexrad radar sites, from which we can assess whether precipitation was occurring, and in many cases, provide an estimate of how much was falling. The only portion of Texas that has very limited nexrad radar coverage is the Big Bend area.
To select a weather reconstruction expert witness, I should mention that you need not waste time asking one of the local NWS forecasters to testify. Federal regulations prohibit NWS employees from testifying in any case wherein the federal government is not a party. Nor can I make a blanket endorsement of other meteorologists in the media. There are some obvious advantages to using the local TV meteorologist who is “in” hundreds to thousands of homes every day or night; potential jurors develop a sense that they know these people personally, and they also develop strong opinions about who they like and who they don’t like. But not all media meteorologists are equipped to do the kind of reconstruction I have mentioned in this article, and you might be better served by someone from a private company that specializes in weather reconstruction.
If you choose to use a local media meteorologist, look for certain minimal qualifications. It isn’t required that a media meteorologist have a degree in meteorology. Years of study, training, and research can certainly make a person qualified to be a meteorologist, and some media meteorologists have taken 40 hours of course work from Mississippi State University (MSU) in a distance learning program. Two national associations of meteorologists, the National Weather Association (NWA) and the American Meteorological Society (AMS), offer some type of certification for broadcasters. At a minimum, a weather expert ought to have completed course work leading to either a B.S. degree in meteorology or atmospheric science or completed the 40-hour MSU program and hold a Certificate in Broadcast Meteorology. The expert also should be a member of one or both of these organizations and hold a certification, such as the AMS Certified Broadcast Meteorologist designation.
Both organizations publish scholarly journals composed of articles written by members or non-members, which appear in print only after passing a peer-review process in which the article is examined by other meteorologists with expertise in the field covered by the article. It is icing on the cake if a weather expert has published a peer-reviewed article in a professional journal such as those published by NWA and AMS. You will find that it is very rare that an active broadcast meteorologist has published in a peer-reviewed journal. (As an aside, the last time I checked, I was the only active media meteorologist in the country who has published in a peer-reviewed journal recently.)
Also consider the fees for professional services. If you hire a private company to perform weather reconstruction, plan on fees consistent with what other forensic experts charge. I did not charge a fee for researching and testifying in Beth’s trial, but I was able to obtain the data she needed quickly, and I considered my work to be worthy of handling on a pro bono basis. Likewise, when I can find information quickly and easily, I don’t charge local police agencies, which is not to say that I would not have to charge fees for weather reconstruction for a Texas prosecutor who required more work than in this case. For the forensic work I have done for attorneys handling personal injury cases in other states, I have a fee schedule that must be agreed to in advance.
Finally, keep in mind that local media meteorologists are under all sorts of pressure from management regarding how they spend their time. In all television markets, there are ratings periods (called “sweeps”) that each last four weeks, during which it may not be possible to depend on local meteorologists to be at a prosecutor’s beck and call. To media companies, the outcome of sweeps is crucial to profitability because the ratings govern how much the station can charge for advertising going forward. Most media companies prohibit on-air talent from being absent during sweeps.
As a closing note, you might think that having tried hundreds of felony trials to juries and having spent over 12 years on-air as a meteorologist, testifying in court in Beth’s trial would have been a piece of cake, but not so! I found myself strangely nervous sitting outside the courtroom waiting to testify, not to mention being a little jittery while on the stand. I was reminded of the respect I had for all of those witnesses who testified in my trials years ago and did so without appearing nervous. When I heard from Beth about the outcome of her trial, I was elated to have had a small part in seeing that justice is done.