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Recent Questions

Question: What is your best estimate for a dry (or lowest chance of rain) Thursday - Sunday in the next 30 days? Looking to schedule an outdoor event. — Cheryl

Answer: It would be nice if we could give you some real meaningful long-term guidance that would help in your planning in a forum like this, but unfortunately, there is a rarely any good way to foresee an especially dry pattern more than a week or so ahead of time, and this overall tendency becomes even more noticeable heading through late spring and early summer, as we head into the time of year where many days will have at least some chance of a passing shower or storm, though often on a rather scattered basis. We don't know how far ahead you have to select your date, but we'd suggest checking our 7-day forecasts and looking for days with a 10% or less chance of rain, or simply choosing a couple of dates a week or so apart and setting one of them as a primary date and the other as a back-up/rain date, if that is practical for your event.
Jun. 2, 2017 | Tags: normals, wral.com

Question: What does localized damaging winds mean? — Vincent

Answer: That phrase indicates we expect the possibility that some storms could produce wind gusts strong enough to topple trees, take down power lines, and perhaps cause some structural damage, especially to outbuildings or mobile homes. In many cases, such damage occurs over very small portions of our overall viewing area, hence we might refer to the potential damaging winds as isolated, or "localized." Of course, regardless of how isolated or localized wind damage might be, if it happens to occur in your location it can be very impactful.
Jun. 1, 2017 | Tags: preparedness, severe weather, winds

Question: Personally, I prefer the dew point. Just so you know, some of us take the opportunity to learn when you use a term we don't understand. — Tim

Answer: We're glad you appreciate the use of dew point - we certainly understand that some others like to consider relative humidity instead, and we do include it in our current conditions and detailed hourly forecasts on the web site. On air, we lean toward dew point for the reasons discussed in a recent post - mainly that when the dew point value changes, you know that the amount of moisture in the air has gone up or down, whereas the relative humidity can change even if the amount of moisture stays the same, since that variable depends on temperature as well as water vapor content.
May. 31, 2017 | Tags: humidity/dew point

Question: In the 11:00 PM newscast on 5/3 you were describing the weather watches that had been issued for portions of the viewing area and you stated that bordering counties that are not included in the watch areas should consider themselves part of the watch. Don't the organizations that issue the warnings include a buffer area in the issued watch? — Rick

Answer: That's an interesting question. We aren't aware that the Storm Prediction Center includes any formally designated buffer in the watch areas that they issue. Rather, they attempt to identify and outline areas where there appears to be a reasonable chance of organized thunderstorm activity that will produce instances of hail 1-inch in diameter or greater, winds gusting to 58 mph or greater, and/or tornadoes. There is inherently some uncertainty associated with the forecasts used to determine the area to be outlined. The small chance that storms will be a little farther east, west, north or south of expectations, or move a little faster or slower, is the reason we occasionally suggest that people near the borders of a watch or warning pay extra attention to the weather, rather than considering the edge of the outlined area a hard and fast cutoff for possible severe weather.
May. 30, 2017 | Tags: maps & codes, preparedness, severe weather

Question: When a tornado is imminent, should you open windows to lessen the pressure in your home? — Susan

Answer: There was an old belief that low pressure associated with tornadoes could cause a house to explode due to higher pressure trapped inside, and that opening windows would allow this pressure to equalize. However, this has been proven an insignificant factor in tornado damage, since even tightly constructed and well-sealed homes have plenty of places for pressure to quickly balance out, and the destruction that occurs during tornadoes is due to high winds rather than pressure differentials. It is far better to stay away from windows and outside walls if a tornado is approaching.
May. 29, 2017 | Tags: folklore, severe weather, tornadoes

Question: Would you consider adding the forecasted dew point to your 7-day? Since that can make a big difference in how comfortable a temp can feel, it certainly would be helpful for viewers planning activities. — A V Walker

Answer: We'll certainly give it some thought, although it may be that we conclude that adding another number in addition to the lows, highs and precipitation probabilities that are already on that graphic would be a little too much. We do occasionally highlight upcoming significant changes in dew point, or unusually low or high values, using a separate graph or a "pullout" graph that we access during the 7-day portion of the TV forecast. Also, for those who visit our web site, you can get projected dew point values out through 7 days by clicking the "View Hourly Forecast" link above the 7-day section, and then looking just below the hour-by-hour forecast that appears, and clicking the "More Details" link.
May. 28, 2017 | Tags: humidity/dew point, wral.com

Question: Early the morning of April 24th (6:00 a.m. ish) there was what sounded like an explosion and it continued for what seemed like a minute. There was no other thunder or any lightening before this or after. It was just once and was the strangest thunder(?) I have ever heard. I was speaking with my mom who lives about 10 miles away and she said they heard the same thing at the same time. How is this possible and was this indeed thunder? — Patricia Vaughn

Answer: We weren't sure of your exact location based on the wording of your question, but did take a look at radar data for that time frame, which was available for visualization at gis.ncdc.noaa.gov/maps/ncei/radar. We found that there were showers and possible thunderstorms in the general region, spreading in from the south. Your description of the thunder you heard did sound unusual, but it does appear at least possible there could have been a lone strike in your vicinity. If you had a strike nearby, but from a lightning flash that happened along a lengthy path that ran from close to your location to a significant distance away, you could have heard thunder for a considerable time, as the sound from successively more distant parts of the path would arrive in sequence, stretching the duration of the resulting thunder. If you happened to be in an area where rain was not currently falling, that can make the thunder seem especially loud, and there is also at least the chance you heard a positive strike, which transfers positive (rather than the more common negative) charge to the surface. If so, these strikes tend to be more powerful and to have a bit longer duration than typical negative strikes. Of course, this is all somewhat speculative, and we can't entirely rule out that there was some other, non-meteorological source of the sound you heard.
May. 27, 2017 | Tags: cool sites, lightning, past weather

Question: Since the broadcast area of WRAL covers an area that could produce a wide range of weather, particularly north to south but also west to east, what specific area are you predicting on your online forecast? — Rick

Answer: When you come to our default main weather page, the forecast shown there applies to the Raleigh-Durham area. Of course, in some situations there can be a range of conditions across even that small region, and if that's the case we attempt to highlight that in the written description of the forecast. For purposes of the 7-day forecast image, we have to choose a single temperature value as a forecast high or low, and a single icon to capture as best we can the prevailing expected weather condition. Because the expected conditions can vary even more widely, as you noted, across our entire viewing area, our web site is set up with a box above the 7-day forecast that allows you to enter a town name or a zip code and click "change." This will replace our local forecast with one that is specific to the location in question. Registered users of our web site who are signed in will see that location on future visits unless they change it to someplace else. Those forecasts for other locations are based on gridded forecast data that accounts for expected differences in temperature, precipitation chance, cloud cover and so on, and under the appropriate circumstances may be very different from our local Raleigh-Durham area forecast.
May. 26, 2017 | Tags: maps & codes, wral.com

Question: Just an interesting note. My Dad is a 1959 or 1960 Gradute of Elon College. One of his professors told the class that if we don't stop paving the earth, flooding will become an increasing problem. I think he hit the nail on the head. — Dina Grinstead

Answer: Replacing permeable, natural areas with more urbanized development featuring significant impervious surfaces and drainage systems has long been recognized as contributing to increased flooding problems. Water that may have soaked into the ground and either recharged groundwater or slowly traveled to creeks and streams instead rapidly runs off or is carried to streams it wouldn't otherwise run into, and in a much shorter time. This has been observed to cause rapid increases in water levels for streams in and near urban areas, while similar rainfall amounts produce slower rises and lower peak levels in rural streams subject to similar rainfall rates. There is a good U.S. Geological Survey fact sheet on the effects of urbanization on flooding, including some ways for developers and municipal planners to mitigate these effects somewhat, at pubs.usgs.gov/fs/fs07603/.
May. 25, 2017 | Tags: climate change, cool sites, flooding

Question: Dear Greg....I am a fellow Pennsylvanian, been here since 1981. Do you remember the tornado event from 1985? — Jane Newberry

Answer: Yes, indeed - you're referring to an outbreak that formed south of a powerful low pressure area, and along or ahead of an especially strong and active cold front, on May 31, 1985. The storm led to tornadoes that formed over Ohio, New York and Ontario as well, with most of them following a west to east track. Overall, there were 43 tornadoes in the outbreak, with 23 of those affecting parts of Pennsylvania. The storms resulted in 89 fatalities, including 22 in Pennsylvania, and since that day there have only been two more tornado days in the entire U.S. with a higher number of deaths. Only once have we in North Carolina had a greater number of tornadoes in our state than Pennsylvania did on that day (there were 30 in NC on April 16, 2011). It's also notable that one tornado in that 1985 outbreak was rated F5, the only twister of that intensity in Pennsylvania history. So far, there has never been an F5 or EF-5 tornado recorded in the Tar Heel state. For more on the 1985 outbreak, including some maps and satellite images illustrating the weather pattern that spawned the tornadoes, see www.weather.gov/ctp/TornadoOutbreak_May311985.
May. 24, 2017 | Tags: cool sites, past weather, severe weather, tornadoes

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