The Value of Adding a Meteorologist To The Investigative Team

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Doppler radar tower over the Fort Lawton Air Defense
Command Operations Building seen from Discovery Park,
Seattle, WA. (Photo by Joe Mabel, Wikimedia Commons.)
Many of the losses roof
consultants, engineers,
and building consultants
are asked to investigate
involve weather. When
handling a weather-related
loss, there are two main areas that can lead
to erroneous or inaccurate conclusions:
selection of weather data and do-it-yourself
analysis.
A tremendous amount of time is spent
trying to find accurate sources of weather
information and data. The amount of “junk”
weather data that exists has grown exponentially
with the arrival of the Internet. For
the layperson, it is not an easy task to determine
which data are accurate and which are
not appropriate for use in an investigation,
particularly one that is currently in litigation
or is headed that way.
Clients often seek the assistance of a
forensic meteorologist after having based
their professional opinion on data that
appeared to be scientifically sound but, in
fact, turn out to be from a source that is not
certifiable. When an insurance claim turns
into a litigated matter, all the data that are
used to form opinions must be able to be
traced to a certifiable source. When you rely
on a professional weather service to select
and procure your data, you are assured
that the weather information you receive is
accurate and current, comes from approved
sources, and can be certified for use in legal
proceedings and trials.
One of the advantages of using a professional
weather service is access to a
very large body of data that provides many
pieces of information from which a weather
reconstruction is born. Approved information
sources that are used in a meteorological
evaluation are the National Weather
Service’s (NWS) hourly reporting stations,
special weather statements, local storm
reports, cooperative reporting stations,
and climate summaries, as well as data
from the National Oceanic & Atmospheric
Administration (NOAA).
Hourly weather data are provided by
the Automated Surface Observing System
(ASOS) and the Automated Weather
Observing System (AWOS). This program
serves as the nation’s primary surface
weather observing network, containing over
800 sites nationwide (mostly at airports),
and is designed to support weather forecasting
and the aviation, meteorological,
hydrological, and climatological research
communities.
Cooperative weather sites are usually
operated by volunteers trained by the NWS
who observe a limited number of weather
variables. Typically, these are daily maximum
and minimum temperatures, precipitation
amounts, snowfall, and snow depth.
The cooperative observer network currently
has over 10,000 active sites nationwide.
The National Climatic Data Center database
of worldwide weather
stations records daily and/
or hourly weather conditions
such as temperature, precipitation,
wind, and snowfall.
Data are reviewed by the
National Climatic Data Center
for a reasonable level of quality
assurance.
The question of when to get
a professional opinion about
past weather conditions is a
complex decision, often influenced
by budgetary restrictions,
customary procedures,
and company policy. However,
it can be the choice that will
determine the validity of your
opinion as to the cause of
a structural failure. The best
way to illustrate this point is
by sharing an example from
our case files.
Case Study
A business owner in
Missouri filed a claim with
his insurance company stating
that the roof of his building
had been heavily damaged by
a severe hailstorm. As a result
of that barrage of hail, rain was
able to pour into the building,
causing extensive damage
to walls and equipment. The
insurance policy stipulated
that damage to the interior of
the building due to rain would
be covered only if rain entered
the building due to natural
causes, such as damage to the
roof or exterior walls by virtue
of strong winds or hail.
The hailstorm that
occurred in that section of
Missouri on that day was well
documented. It caused extensive
damage to homes, vehicles,
and businesses. The insurance investigator
found a hail report on the Internet
that showed the size of hail in the area of
this building to be approximately one-half
inch in diameter. In addition, the weather
data he looked at from the nearest airport
showed maximum winds that day of 15
mph, certainly not high enough to be considered
damaging winds.
Based on his findings, the company
denied the claim. The building owner was
not satisfied and hired a consultant to
investigate further. We were asked to provide
an analysis of all weather conditions
that occurred at the site of the loss.
The process employed by the forensic
meteorologist involved analysis of surface
weather observations, storm reports, and
other special weather statements, as well as
Doppler radar images. The analysis showed
that during the hail-producing thunderstorm,
wind speeds were in the range of
D e c e m b e r 2 0 1 3 I n t e r f a c e • 3 1
An ASOS all-weather precipitation accumulation gauge (AWPAG) at Eureka Airport, Nevada. (Photo from
Wikimedia Commons.)
3 2 • I n t e r f a c e D e c e m b e r 2 0 1 3
60-70 mph, causing the hail to hit the
building with increased force. Based on
these findings, the business owner was
able to prove to his carrier that wind-driven
hail was responsible for the damage to his
building.
Meteorologists often use Doppler radar
in their analysis to fill in the gaps found in
other more traditional data. In the hands
of a trained, experienced expert, Doppler
radar analysis may offer additional insight
and facts that would not be considered in
a traditional analysis. Doppler radar may
be used to determine wind speeds up to 74
mph at the exact location of loss. It can also
be used to see if the “hook echo” or tornado
vortex signature (TVS) was present, and
this is an important clue for determining
whether a tornado may have formed in a
particular area.
The Next-Generation Weather Radar
system (NEXRAD) is composed of 159 landbased
Weather Surveillance Radar-1988
Doppler (WSR-88D) sites throughout the
United States and select overseas locations.
This system is a joint effort by the United
States Departments of Commerce (DOC),
Defense (DOD), and Transportation (DOT).
The controlling agencies are the NWS, Air
Force Weather Agency (AFWA), and Federal
Aviation Administration (FAA), respectively.
Radar scans at radial distances typically
greater than 100 miles, covering
an area larger than 30,000 square miles
around each radar site. It helps provide estimates
of several weather elements that aid
in weather forecasting and meteorological
research—some of which include location
and intensity of precipitation, storm attributes,
storm track and speed, and precipitation
amounts.
National Weather Service forecasts and
advisories are often overlooked by nonprofessionals,
but they—along with warnings
and watches that may have been issued
for a specific area—are important in the
reconstruction process. Analyzing what type
of weather was expected in an area can
provide validity as to whether atmospheric
conditions were favorable to support certain
weather conditions.
In summary, the analysis of weather
conditions at a specific location on a specific
day is a complex process, one best left to
a professional who can add value to your
investigation and subsequent report.
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Patricia Robertson is an account executive with CompuWeather, the FleetWeather
Group. CompuWeather is the largest worldwide provider of forensic weather data.
Established in 1976 in Hopewell Junction, NY, the company has managed over 67,000
insurance claims and legal cases.
Patricia Robertson
RCI has released a Call for Papers for the 2014 Symposium on Building
Envelope Technology to be held in Tampa, Florida, October 20-21, 2014.
Abstracts of no more than 200 words in length should be received at RCI by
April 28, 2014, with papers due July 14. All submitted abstracts and papers must
be original to the author and not previously published or presented nor scheduled
for publication or presentation in any other publication or venue.
Topics sought include: innovative technologies and practices, façade systems
and technologies, the building envelope as a design statement, energy conservation
design, designing façades that will improve indoor air quality, economics and
life cycle analysis, panelized stone or masonry systems, sealants, hygrothermal
analysis in façade designs, facades designed to achieve sustainability, curtain
walls, double-wall facades, roofing, brick masonry, stone masonry, waterproofing,
stucco, EIFS, metal wall panels, air barrier systems,
testing wall systems, and construction processes.
For further information regarding the
process for abstract and paper submittal,
contact RCI Director of Conventions and
Meetings Karen McElroy, 1500 Sunday
Dr., Ste. 204, Raleigh, NC 27607. Phone:
800-828-1902; fax: 919-859-1328;
e-mail: kmcelroy@rci-online.org.
Call for Papers for RCI 2014
Building Envelope Symposium
in Tampa, Florida