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Answer: If there is not a designated ground-level or basement shelter area that is readily accessible and that you have time to get to based on prior forecasts or the timing of warnings and speed of the approaching system, then the next best action is to take cover in a small interior room of the apartment. The idea is to be as far as you can from the outside walls and to have as many walls between your location and the outdoors as possible. This reduces your exposure to debris associated with any window or outside wall breaches that may occur if the tornado makes a direct strike or drives any outdoor objects through the walls. If there is time and it is practical, it can also be useful to surround yourself with coverings like cushions or mattresses.
Apr. 21, 2013 | Tags: tornadoes, weather & health

Answer: As you imply in your question, tornadoes fall very much into the category of very high impact, but very low probability for any individual location. When it comes to statistics, rare and sporadic events like tornadoes present a number of difficult questions to those attempting to quantify the risk in a meaningful way, and thus a range of efforts have yielded a range of estimates that depend on the specific techniques and on whether the probabilities relate to the likelihood of striking some part of a county, a city, an individual structure, etc, and in some cases weaker tornadoes that are likely to produce only cosmetic damage are excluded. All that being said, for central NC the estimates from a sampling of studies by personnel from NOAA,DOE and others point to probabilities of striking a particular point in a given year (for any strength tornado) ranged from about .2% to .03%, corresponding to one tornado striking a given property about every 500 to 3300 years. When these studies limit the tornadoes to the more destructive and injurious tornadoes having intensities of F2 and higher, the probabilities drop to .02% to .005%, yielding one strike of that magnitude on a particular site about once every 5000 to 18,000 years.
Feb. 25, 2013 | Tags: past weather, preparedness, tornadoes, weather & health

Answer: Because that temperature is 16 degrees above the freezing point of water, you would not freeze. However, 48-degree water is still quite cold relative to a human's body temperature and, assuming you were not wearing special protective clothing and remained in the water, you would rapidly lose heat to the water and either perish from exhaustion and drowning within about 45 minutes to an hour, or from hypothermia in 1-3 hours. For a brief overview of what happens upon immersion in cold water, see www.ussartf.org/cold_water_survival.htm.
Feb. 15, 2013 | Tags: cold, lakes and rivers, weather & health

Answer: Most people experience frequent changes in barometric pressure as high and low pressure centers and front pass though, or larger ones when flying, scuba diving or traveling in mountainous areas, and do not experience vertigo. However, there have been documented cases of some more sensitive individuals experiencing vertigo with strong pressure changes (divers and pilots, for example), and it seems reasonable to think those with diseases or syndromes involving the inner ear could have vertigo attacks that are triggered by the smaller variations associated with weather systems. For any particular person, though, it would be best to consult a doctor about whether there could be a connection between vertigo and air pressure.
Feb. 13, 2013 | Tags: weather & health

Answer: That bit of folklore seems to rest on the idea that the first snow will remove contaminants from the air that could be bad for someone consuming snow cream made with it. However, that ignores the fact the the "second snow" or any that follow are likely to have had as much of an interval since the first one as the first snow had since the most recent rain, which should have accomplished the same sort of contaminant removal, or that any pollutants in the air that are scoured out by precipitation are likely to recover to their typical background levels quite rapidly once a precipitation system has moved out of the area. Bottom line is, so long as the snow is deep enough and "fluffy" enough to make otherwise aesthetically pleasing snow cream, there is very little likelihood that freshly fallen snow collected from an open area, and otherwise undisturbed, would contain pollutants or contaminants in sufficient quantity to be a health hazard, regardless of whether it is the first of the winter or not.
Feb. 6, 2013 | Tags: folklore, snow, weather & health

Answer: A fairly strong low pressure center did move quickly across the area from southwest to northeast that day, with the pressure falling rapidly from around midnight out to about 2 PM, becoming fairly steady for about 3 hours, then rising slowly after 5 PM. You can see a graph and the associated hourly numbers for pressure at www.wunderground.com/history/airport/KRDU/2012/12/26/DailyHistory.html.
Jan. 13, 2013 | Tags: cool sites, past weather, weather & health

Answer: The storm you mentioned was crossing the northeastern U.S. on the day you wrote (Friday, Dec 21, 2012) and at the time had a central sea level pressure of 981 millibars. To give a sense of scale to this, the average sea level pressure is about 1013 mb, while a typical high pressure center may have a central sea level pressure around 1030 mb. What's going on near the center of a low is air that spirals in toward that center is rising at a rate that depends on how fast air at higher altitudes is being removed from the vertical column of air above the point near the center. If air is being removed more rapidly aloft than it spirals in below, then the surface low deepens, and the pressure becomes lower. In addition, of course, if the low is moving fast, a person in an area that it approaches will experience rapidly falling barometric pressure and vice versa when it moves away.

Some people do report a flare-up of physical symptoms such as joint pain and headaches in these situations. This can be thought of as somewhat similar to the effects of driving or flying through various altitudes, and of course many of us have felt the effect of pressure changes in these situations, often without much discomfort, but sometimes an illness may exacerbate the effects, and some people appear to be much more sensitive than others. The pressure changes involved with a passing low of the sort that was active on the day you wrote, if a person was under a high pressure center one day and the center of the low the next, would be about the same as changing altitude by about 1300 feet or so over that same amount of time. When people dive underwater, a much greater potential pressure change has to be dealt with, as the pressure increases by about 1013 mb for every 33-34 feet of increasing depth below the surface.
Dec. 31, 2012 | Tags: fronts & airmasses, weather & health

Answer: Around 1700 Zulu, maybe? We don't really know, but it sounds like a nice place to escape the pressures of the day, shoot the breeze with other weather folks, clear the mental fog and generally un-wind. Maybe those thoughts will precipitate a few other puns from the folks who suffer through reading this response!
Dec. 30, 2012 | Tags: folklore, weather & health

Answer: Sandy did have a very low central pressure, but due to the difficulty in relating central pressure to wind speed, storm surge and overall damage potential in hurricanes (due to a poor correlation between them and many exceptions to any generalized rules), there actually is no such thing anymore as a "Category 4" pressure. Due to the issues mentioned, pressure (and storm surge) were removed from the Saffir-Simpson Hurricane Intensity Scale, and it was renamed the Saffir-Simpson Hurricane Wind Scale, beginning operationally with the 2010 season.

Sandy was a good example of a storm that only reached Category Two and then made landfall as a post-tropical storm with Category One equivalent winds, but it's large size, the long duration of strong winds, it's direction and speed of motion, and the shape of the shoreline where it struck all yielded high storm surges and the accompanying damage. There is a lot of work underway in post-storm assessments to address whether any changes are needed in the way warnings and advisories are communicated, and how, if possible, the process can be improved.
Dec. 19, 2012 | Tags: flooding, hurricanes, weather & health, winds

Answer: That should be the case, with either an e-mail, phone call or letter to indicate it is time to choose whether to renew. If you need to check with the WeatherCall provider on the status of your account, you can log in, or contact them by phone, e-mail or letter using the information provided on our main WeatherCall page at www.wral.com/weather/page/3567856/.
Nov. 27, 2012 | Tags: severe weather, weather & health, wral.com