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Answer: There were clearly thunderstorms in the area on the afternoon and evening of 22 Sep 09, as documented by a series of METAR observations from the Raleigh-Durham airport (see www.wunderground.com/history/airport/KRDU/2009/9/22/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA for a listing). As far as specific lightning strike data goes, that information is not publicly available and must be requested in the form of a fee-based "lightning forensics" report from one of two private companies. See the following addresses for more information. You may want to request that the insurance company provide a report, or cover your cost to obtain such a report, from one or both of these sources that shows whether lightning was observed by their networks within 5-10 miles of your address. If it was, the combination of lightning data and the diagnoses from your telephone and air conditioning repair personnel would seem to make a strong case that lightning caused the damages in question. See www.uspln.com/forensics.html and www.vaisala.com/weather/products/lightning/dataarchivereports/strikenetfax (click the "FAQ" link at this address for more details).
Oct. 16, 2009 | Tags: cool sites, lightning, past weather, thunderstorms

Answer: In the United States, mountains that are affected by hurricanes are far enough inland that the hurricanes have usually weakened considerably in terms of wind speed, though there can be some instances of wind damage. Storm surge is only an issue in coastal areas. Flooding, however, has had a major impact in the Appalachian mountains from decaying hurricanes and their remnants, as the storms often remain moisture-laden and may produce very high rain rates that can be enhanced by air forced upward by the rising terrain. In addition, the rugged topography in the mountains can concentrate and channel the rainwater in such a way as to create intense flooding and sometimes very destructive landslides.
Oct. 15, 2009 | Tags: flooding, hurricanes

Answer: As is often the case in meteorology, there are notable exceptions to a broad generalization like this, but typically a surface high pressure center is associated with gently sinking air, which tends to result in fair skies, fairly low humidity and little or no precipitation. Low pressure centers, on the other hand, are usually regions in which air is forced upward, leading to the development of clouds and sometimes precipitation.
Oct. 14, 2009 | Tags: fronts & airmasses, general meteorology

Answer: The center of Hurricane Hugo sped into North Carolina the morning of September 22, 1989 after crossing the South Carolina coastline around Charleston the evening before. You can see details of its track by selecting it from the "Major NC Storms" box on our interactive hurricane tracker in the "hurricanes" section of our web site. The devastating tornado that reached F4 intensity, destroyed the northwest Raleigh K-Mart, and killed 2 people each in Wake and Nash counties, touched down around 1 am on November 28, 1988 in Umstead State Park and then followed an 84-mile path toward the northeast that ended near Jackson in Northampton County. As the dates illustrate, these two systems were not related. You can see much more about the Raleigh tornado in a National Weather Service event summary at www4.ncsu.edu/~nwsfo/storage/cases/19881128/.
Oct. 13, 2009 | Tags: cool sites, hurricanes, past weather, tornadoes

Answer: If you are referring to linear or curved lines extending from high-altitude aircraft, the cloud involved is typically composed of a combination of frozen droplets or directly deposited ice crystals that form as water vapor in aircraft exhaust mixes with very cold ambient air, and low concentrations of combustion products such as soot and oxides of carbon, nitrogen and sulfur. These are called condensation trails, or contrails, and they are quite common, existing in a variety of forms depending on the temperature, moisture, stability and wind shear characteristics of the layer of air in which the aircraft is traveling. In especially dry air, they can fail to form or can be so short-lived as to be nearly invisible, while in especially humid air they may be sufficiently persistent to spread, merge and form a layer of cirrus cloud covering much of the sky. The term chemtrails has been applied to trailing clouds by some web site owners who believe materials other than exhaust products are being deliberately released by aircraft in what they purport to be covert and widespread government or corporate projects.
Oct. 12, 2009 | Tags: air quality, clouds

Answer: They can definitely be a little difficult to interpret, since the river "level" does not directly tell you the depth. For rivers, gage stations are established at various points, which measure the height of the river surface above a "zero datum" unique to that location, and the river flow is then estimated from that measured height, or stage. Also, certain heights relative to the datum are designated as flood stage, again unique to the specific site. For example, along the Tar River, there is a gage at Louisburg. The zero height there is 175.75 feet above sea level and flood stage is 20 feet above that point, or 195.75 feet above sea level. Downstream at Rocky Mount, the gage zero is at 52.8 feet above sea level, with flood stage 15 feet above that zero point. You can check the latest measurements and get much more info on these and other gages in our area, at newweb.erh.noaa.gov/ahps2/index.php?wfo=rah. You might also find the info an links at water.usgs.gov/nsip/definition9.html helpful.
Oct. 11, 2009 | Tags: cool sites, lakes and rivers

Answer: Because meteorology careers span such a wide variety of specialties and very different types of organizations to work for, from consultants to broadcasters, from academia to the military and more, it is tough to cover in a small space like this in any detail. However, there is an excellent set of links covering a broad array of information on employment opportunities and working conditions for meteorologists at www.nssl.noaa.gov/faq/faq_careers.php. You may find the resources under "Profile of Atmospheric Science Careers" and "Career Guidance" on that page especially helpful.
Oct. 10, 2009 | Tags: careers & education, cool sites

Answer: A glance at data for Hammonton on the NWS Precipitation Frequency Data Server confirms that you were directed toward the right ballpark on the 20-hour rainfall return interval, as the resulting graphs appear to place that amount of precipitation over that time frame at about a 3-4 year return period. A similar check for 2.2 inches of rain over a a 2.5 hour span turns up a rather similar return period of about 4-5 years. If you'd like to explore that site yourself, it is located at hdsc.nws.noaa.gov/hdsc/pfds/. Just click on the state of interest and select the location you want to research.
Oct. 9, 2009 | Tags: cool sites, past weather, rain

Answer: The track of tropical cyclones is influenced by the rotation of the earth and by the position of the storm relative to other weather features such as large scale pressure troughs, ridges, highs and lows, along with the distribution of sea surface temperatures and surrounding areas of colder or warmer, or drier or more humid air. Many of these factors are accounted for to varying degrees by a large suite of computer models that project the future path. Some of these models are specific to tropical systems while others are also more general weather forecasting tools. Sometimes, a group of models will produce an average or consensus result that is more accurate than any single model alone. Over the past couple of decades, track forecasts have improved greatly due to improved models and better methods of collecting data with which to initialize those models.
Oct. 8, 2009 | Tags: hurricanes

Answer: The number that you see given as a current lake level is the elevation of the lakes surface above mean sea level, and for each lake there area a series of such levels that have meaning in terms of water supply, recreation, wildlife management, flood control and in some cases power generation. The levels do not directly give you a water depth. As one example, at Falls Lake, a level of 251.5 feet is established as the "conservation pool" or "guide level," and is the target elevation considered ideal by the Corps of Engineers. For an idea of the various levels that have other meanings, and how they relate to water volume and surface area of the lake, see epec.saw.usace.army.mil/FALLPERT.TXT. For more general information about the lake projects in our area, go to epec.saw.usace.army.mil and click on any of the lake names listed toward the bottom in the blue-shaded boxes.
Oct. 7, 2009 | Tags: cool sites, lakes and rivers