FORENSIC WEATHER CONSULTANTS, LLC

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1 SAMPLE, CONDENSED REPORT DATES AND LOCATIONS HAVE BEEN CHANGED FORENSIC WEATHER CONSULTANTS, LLC Howard Altschule Certified Consulting Meteorologist 1971 Western Avenue, #200 Albany, New York (P) FORENSIC WEATHER INVESTIGATION OF THE WEATHER CONDITIONS AND THE OCCURRENCE OF HAIL FOR THE PERIOD JUNE 6-7, 2010, AT 20 MAIN STREET IN DOTHAN, COLORADO December 14, 2014 CASE NAME: Homeowner v. Insurance Company DATES OF INCIDENT: June 6-7, 2010 PREPARED FOR: Mr. Esquire, Esquire ASSIGNMENT: This case was assigned to me by Mr. Esquire, Esquire. I was asked to perform an in-depth weather analysis and forensic weather investigation at 20 Main Street in Dothan, Colorado in order to determine the weather conditions and the occurrence of hail. 1

2 METHODOLOGY: Forensic Weather Consultants, LLC uses only the most trusted and reliable sources of weather information that can be certified by the federal government. The location of the incident was plotted by our office and is indicated by a red pushpin. This map will help give you an approximate location of the weather stations we used in this study. In order to perform my analysis of the weather conditions that existed, I obtained and reviewed official copies of the following weather records: a. National Weather Service Hourly Surface Weather Observations/Quality Controlled Local Climatological Data (QCLCD) from Centennial Airport in Denver, Colorado (approximately xx miles southeast of the incident location). b. Cooperative observer weather station reports from Marston Filter Plant, Colorado (approximately xx miles west-northwest of the incident location). c. The publication entitled Storm Data 2

3 d. Super-resolution Base Reflectivity and Storm Relative Velocity Doppler Radar images from the Denver, Colorado radar site were zoomed in over the incident location. e. Probability of Severe Hail (POSH) and Maximum Estimated Hail Size (MESH) Algorithm images from the Denver, Colorado radar site were zoomed in over the incident location. f. Volume Scan Reflectivity Data Zoomed In Over the Incident Location g. Various weather bulletins, advisories and statements that were issued by the National Weather Service in Denver, Colorado. h. Upper air sounding and text data from Denver, Colorado Storm Data publications from the National Climatic Data Center and Local Storm Reports from the Denver, Colorado National Weather Service office were obtained and plotted on a Google Earth Pro program. The weather data and Climatological records used for this analysis are the official records that Meteorologists rely upon every day during the normal course of business and are either kept in our office or at the National Climatic Data Center. Super-resolution Doppler radar images were used in this study. Doppler radar images are useful for locating precipitation. As the radar unit sends a pulse of energy into the atmosphere and if any precipitation is intercepted by the energy, part of the energy is scattered back to the radar. These return signals, called radar echoes, are assembled to produce radar images. Doppler radar images are received approximately every 6 minutes. It should be noted that the radar image date and time stamps that are given on the Doppler radar images are given in GMT, which is Greenwich Mean Time. In order to convert GMT to Mountain Daylight Time (MDT), a subtraction of 6 hours is necessary. METEOROLOGICAL ANALYSIS FOR JUNE 6, 2010 On June 6, 2010, Doppler radar images that were zoomed in over the incident location and nearby surface observations indicated that numerous showers and thunderstorms with light to occasionally moderate, heavy and torrential rainfall occurred from approximately 7:40 p.m. through 11:33 p.m. Within this timeframe, strong thunderstorms occurred between 11:01-11:28 p.m. The following severe weather warnings were issued for the incident area in Southwestern Sample County, Colorado on June 6, In addition, LSR s were also received from the area and are listed below. 3

4 NATIONAL WEATHER SERVICE WARNINGS ON JUNE 6, 2010 FOR THE LOCATION OF THE INCIDENT: On June 6, 2010, the National Weather Service in Denver, Colorado issued a Severe Thunderstorm Warning that was in effect from 11:02 p.m. through 11:45 p.m. on June 6, 2010 which stated: WUUS55 KBOU SVRBOU COC /O.NEW.KBOU.SV.W T0502Z T0545Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DENVER CO 1102 PM MDT WED JUN THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... NORTHEASTERN DOUGLAS COUNTY IN NORTHEAST COLORADO SOUTHWESTERN SAMPLE COUNTY IN NORTHEAST COLORADO * UNTIL 1145 PM MDT * AT 1102 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING HALF DOLLAR SIZE HAIL... AND DAMAGING WINDS UP TO ABOUT 60 MPH. THIS STORM WAS LOCATED NEAR SURREY RIDGE...OR 15 MILES SOUTH OF DENVER...ANOTHER STORM WAS LOCATED SOUTH OF LITTLETON...BOTH STORMS WERE MOVING NORTHEAST AT 10 MPH. At 11:11p.m. on June 6, 2010 the National Weather Service in Denver, Colorado issued an update to the Severe Thunderstorm Warning that was in effect: WWUS55 KBOU SVSBOU SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 1111 PM MDT WED JUN COC /O.CON.KBOU.SV.W T0000Z T0545Z/ DOUGLAS CO-SAMPLE CO PM MDT WED JUN A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1145 PM MDT FOR SOUTHWESTERN SAMPLE AND NORTHEASTERN DOUGLAS COUNTIES... AT 1111 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO GOLF BALL SIZE...AND DAMAGING WINDS UP TO ABOUT 60 MPH. THIS STORM WAS LOCATED 3 MILES SOUTHWEST OF FOXFIELD...OR 13 MILES SOUTHEAST OF DENVER...MOVING NORTHEAST AT 10 MPH. NATIONAL WEATHER SERVICE LOCAL STORM REPORT S (LSR S) FROM JUNE 6, 2010 At 11:44 p.m. on June 6, 2010 the National Weather Service in Denver, Colorado issued the following Preliminary Local Storm Reports Summary NWUS55 KBOU LSRBOU PRELIMINARY LOCAL STORM REPORT...SUMMARY NATIONAL WEATHER SERVICE DENVER CO 1144 PM MDT WED JUN TIME......EVENT......CITY LOCATION......LAT.LON.....DATE......MAG.....COUNTY LOCATION..ST.....SOURCE.....REMARKS PM HAIL 3 SW CENTENNIAL 39.57N W 4

5 06/06/2010 M0.50 INCH SAMPLE CO TRAINED SPOTTER HAIL COVERED THE GROUND TO A DEPTH OF THREE INCHES 1112 PM HEAVY RAIN 4 NNW CASTLE ROCK 39.43N W 06/06/2010 M3.50 INCH DOUGLAS CO TRAINED SPOTTER HAIL ACCUMULATIONS RANGED FROM A DEPTH OF TWO TO FIVE INCHES 1110 PM HAIL CENTENNIAL 39.60N W 06/06/2010 M1.00 INCH SAMPLE CO TRAINED SPOTTER 1108 PM HAIL LONE TREE 39.54N W HAIL COVERED THE GROUND TO A DEPTH OF TWO INCHES 1100 PM HAIL CENTENNIAL 39.60N W 06/06/2010 M2.00 INCH SAMPLE CO TRAINED SPOTTER HAIL COVERED THE GROUND TO A DEPTH OF THREE INCHES 1055 PM HAIL LONE TREE 39.54N W 1035 PM HAIL HIGHLANDS RANCH 39.55N W 06/06/2010 M1.75 INCH DOUGLAS CO TRAINED SPOTTER 1029 PM HAIL 5 ENE PERRY PARK 39.30N W 06/06/2010 E0.88 INCH DOUGLAS CO TRAINED SPOTTER HAIL COVERED THE ROAD TO A DEPTH OF 8 INCHES DEEP. POWER OUT WITH SNOW PLOWS PLOWING ROADS 0940 PM HAIL PARKER 39.51N W 06/06/2010 M1.25 INCH DOUGLAS CO PUBLIC 0930 PM HAIL HIGHLANDS RANCH 39.55N W 0903 PM HAIL HIGHLANDS RANCH 39.55N W 0858 PM FLASH FLOOD 8 S MANILA DOTHAN 39.64N W 06/06/2010 SAMPLE CO TRAINED SPOTTER QUINCY ROAD CLOSED DUE TO FLOODING OVER ROAD 0857 PM TSTM WND GST DENVER INTL AIRPORT 39.87N W 06/06/2010 M66.00 MPH DENVER CO MESONET 0856 PM HAIL 9 NNE PARKER 39.63N W 06/06/2010 M1.00 INCH SAMPLE CO TRAINED SPOTTER HAIL COVERED THE GROUND TO A DEPTH OF TWO INCHES 0854 PM HAIL 1 W THE PINERY 39.46N W NICKEL TO QUARTER SIZED HAIL COVERED THE GROUND TO A DEPTH OF SEVERAL INCHES 0851 PM TORNADO 9 E PARKER 39.51N W 06/06/2010 ELBERT CO TRAINED SPOTTER ON THE GROUND FOR SEVERAL MINUTES ATMOSPHERIC SOUNDING DATA FROM DENVER, COLORADO The following atmospheric sounding diagram was calculated during the late evening hours of June 6, This sounding depicts the atmospheric temperature profile amongst other variables. Analysis of the textual data indicates that the environmental freezing level was located at 15, 302 feet above the ground. It is well known amongst the meteorological community that Severe Hail is often associated with 50 dbz values that are present in the atmosphere above the freezing level. DOPPLER RADAR ANALYSIS The Following Doppler radar images were processed by the Denver, Colorado radar facility and contain Base Reflectivity, Storm Relative Velocity, Probability Of Severe Hail (POSH), Maximum Estimated Hail Size (MEHS) and in addition to Volume Scan data. The images were zoomed in over the incident location which is indicated by a red dot on the radar map. 5

6 Dual Panel Base Reflectivity and Storm Relative Velocity from 12:52 a.m. on June 7, 2010 The following dual panel Doppler radar image was processed at 06:52:38 GMT (12:52 a.m. MDT) on June 7, 2010 and depicts Base Reflectivity (left) and Storm Relative Velocity (right). This image indicates severe squall line with very intense precipitation about to move over the incident location. Dual Panel POSH and MEHS from 12:52 a.m. on June 7, 2010 The Following Doppler radar image was processed at 06:52:02 GMT (12:52 a.m. MDT) and depicts Probability Of Severe Hail (left) and Maximum Estimated Hail Size (right). This image shows a 45.8 percent Probability Of Severe Hail and a Maximum Estimated Hail Size of approximately 0.42 over the incident location. 6

7 According to a quality-controlled and confirmed Storm Data report, at 12:55 a.m. on June 7, 2010, hail to 1.00 in diameter fell 2 Miles South-Southwest of Glenn. The image above indicates that the Maximum Estimated Hail Size was 1.07 (~1.00 ) 3 minutes before the hail occurred. Given the ground-truth measurement of 1.00 and that the MEHS was also indicating 1.00 diameter hail over the same area, the MEHS algorithm was doing an excellent job and is deemed reliable. Volume Scan from 12:57 a.m. MDT on June 7, 2010 The following Doppler radar image was processed at 12:57 a.m. MDT on June 7, 2010 and depicts a Volume Scan over the incident location. This image indicated reflectivity well over 50 dbz reaching a height of approximately 29,000 feet over the incident location. In addition, values over 60 dbz were reaching 18,000 to 23,000 feet over the incident location. Not only is this indicative of Severe Hail, but it is indicative of very large, severe hail. 7

8 CONCLUSIONS In conclusion, it is my opinion that: Several strong and severe thunderstorms moved over the incident location on June 6 th and 7 th, Numerous Severe Thunderstorm Warnings were issued for Southwestern Sample County, Colorado during the late evening on June 6 th, 2010 and in the early morning hours of June 7 th, 2010 with specific reference to Dothan, Colorado. Various Doppler radar images indicated that the severe squall line strengthened less than 1 miles west of the incident location and contained very large, severe hail over the incident location. Given the ground-truth measurement of 1.00 hail and that the MEHS was also indicating 1.00 diameter hail over the same area at the same time, the MEHS algorithm was doing an excellent job and is deemed a very reliable resource in this investigation. Hail as large as in diameter occurred at the incident location between 12:56 to 1:05 a.m. on June 7, 2010 as the severe squall line passed overhead. Given the severity of the squall line on Doppler radar and the information on the National Weather Service Warnings, wind gusts of MPH occurred. CERTIFICATION I certify that the above information contained in this report is true and accurate to the best of my ability and that all of my opinions, findings, estimations and interpolations expressed in this report were made with accuracy as a professional meteorologist within a reasonable degree of meteorological certainty. By: Howard Altschule Certified Consulting Meteorologist Forensic Weather Consultants, LLC Certified Consulting Meteorologist (CCM) Certificate #693. Awarded by the American Meteorological Society. 8