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Recent Questions

Question: We have a home on Cameron Hill Rd in Cameron, and the storms that hit last Friday cut a path of destruction at our house and the surrounding area that looks like a tornado hit here, but I did not get a tornado warning. Was there a tornado? — April

Answer: A cluster of thunderstorms late that afternoon and early evening cycles rapidly through development and dissipation over parts of Moore, Chatham, Lee, Harnett, Cumberland and Hoke counties. While they did not produce any tornadoes, they did generate some downdraft/outflow winds that were strong enough to cause pockets of damage. There were three severe thunderstorm warnings issued by the NWS in association with these cells, the first two covering parts of Chatham and Lee counties, and the final one covering the southeastern corner of Moore, along with parts of Hoke, Cumberland and Harnett counties. It appears a few damaging wind gusts did extend outside the boundaries of the warning area over eastern Moore County, and that the northwestern corner of the warning area was just a little south of your location, leaving you out of the warnings that were issued.
Jul. 31, 2016 | Tags: past weather, severe weather

Question: Why is lightning often associated with volcanic eruptions? I visited Kyushu two years ago and saw the Sakurajima volcano then. In online photos of eruptions since then they often had lightning within the smoke plume. — Charlie Smith

Answer: Many volcanoes that generate large ash and/or condensed steam clouds during energetic eruptions likewise produce an array of lightning discharges, some very similar to thunderstorms and others in the form of very small discharges that may only travel a few feet. The precise mechanisms of charge separation that produce lightning in any form remain poorly understood, but the general idea is that particles (in the case of volcanoes, pulverized bits of glass, minerals and rocks, sometimes together with water droplets and ice particles formed from a combination of water vapor released from the volcano itself or from lakes, snow cover or glaciers on or around it) that are violently and turbulently lifted into the air can become electrically charged by transferring electrons from one to another so that a surfeit or deficit develops in individual particles. Then, a separation process occurs that concentrates particles having negative charges in some layers or pockets of the cloud and results in other pockets or layers favoring positive charges.

When the difference in charge becomes great enough between a positive area and a negative one, the insulating properties of air are overcome and a "spark" occurs, carrying current from one point to the other, often within the cloud but sometimes to an oppositely charged point on the ground (the earth's surface is, on average, negatively charged, but positively charged "shadow areas" on the surface can form underneath strong negative charge centers in the lower levels of clouds).

As you noted in your message to us, there is a nice photo of a bolt from the Sakurajima cloud in an article at www.asahi.com/ajw/articles/AJ201607260026.html.
Jul. 30, 2016 | Tags: cool sites, lightning, volcanoes

Question: I'm curious about the LOWEST dewpoint ever recorded for this area? — James

Answer: The lowest dew point ever observed at the RDU airport was a very dry -28 degrees Fahrenheit on Jan 21, 1985, while for comparison purposes the highest was a steamy 82 on Aug 10, 2007. Those numbers are known to us thanks to a special search of hourly observations carried out by the State Climate Office to identify a few of the highest and lowest hourly dew point readings in the airport database.
Jul. 29, 2016 | Tags: humidity/dew point, records/extremes

Question: Amazing lightning storm in the north. How do we email video to you? — Faye Draper

Answer: We're always happy to receive interesting weather videos and photos from viewers. The best way to send them these days is though the "ReportIt" section of our web site, which includes a place for you to provide a text description as well as attach your movies or images. The form is located at www.wral.com/wral-tv/aboutus/page/4519353/, or you can enter "reportit" in the search form on any page on our site, or you can send an e-mail to reportit@wral.com with the image or video files as attachments.
Jul. 28, 2016 | Tags: cool sites, wral.com

Question: When does it usually start to cool down, with temps in the 70s during the day? — Todd Fair

Answer: While an odd day with a high in the 70s has been observed anytime through the summer, they are quite rare. As we head into early September, however, there is a slowly increasing chance of having some days with highs that cool, as indicated by the fact that the standard deviation around the normal for high temperature on a given date by then is about +/-6 degrees, and by Sep 2nd our normal high is down to 86 and declining fairly steadily week to week. On September 23, our normal high drops below 80 degrees (to 79.8) and remains in the 70s through October 25th, when it is 70.2 degrees. Of course, due to increasing variability through the cooler parts of the year as compared to the warmest, we have a number of days with highs in the 70s well outside that period where highs in the 70s are "normal."
Jul. 27, 2016 | Tags: normals, past weather

Question: If a Supercell hits, what would happen? — Aiden Hatch

Answer: Like a lot of meteorological phenomena, it depends on the particulars of that supercell and the environment it forms in, as supercell thunderstorms can have a range of intensities. The term describes a thunderstorm that has a particular structure that involves a rotating updraft and an organization that maintains a different location for strong inflows and updrafts as compared to downdrafts and outflows. Under ideal conditions, this can allow for a self-sustaining storm that has a long life span and con travel great distances. When a rather intense supercell passes over a location it is capable of producing very strong and perhaps damaging straight-line wind gusts, large hail, frequent lightning, very heavy rainfall and in some cases tornadoes. The great majority of notable tornadoes are produced by supercell thunderstorms.
Jul. 26, 2016 | Tags: severe weather, thunderstorms, tornadoes

Question: Is there a simple way to gather barometer readings over a period of time (week, month, etc.)? For the first time in my life I'm getting headaches and my doctor has run some tests but has told me to make a chart of air pressure to see whether changes influence to frequency of my headaches. — Einar Bohlin, Wake Forest

Answer: We're sorry to hear about the headaches, and wish you success in treating them. You can use the "Almanac" section of our web page to access data on barometric pressure, including hourly observations that can be graphed over a day, a week or a month's time. Just go to the Almanac page, then click the blue "send" button under "Get Historical Data." At the resulting page, you have the option to change to any date, and also can choose to display data in daily, weekly or monthly format. When you scroll down from the top of the page, you'll see a number of graphs, including one that shows pressure readings. On any daily page, you can also scroll down farther and see a listing of hourly observations that includes pressure. The pressure trace for the RDU airport should be reasonably representative for your purposes in Wake Forest, but if you'd like to check for consistency you can also use the "Search for another location" box along the right hand side of the page and choose to view data from the Louisburg airport. In either case, take care to pay attention to the vertical scale of the pressure graph, as it may vary some depending on how big a spread of pressures is covered during the span of time shown on the graph.
Jul. 25, 2016 | Tags: cool sites, past weather, weather & health, wral.com

Question: WRAL used to have temperature and heat index graphs for the entire day. Where can I find the max temp and heat index for a particular day? — Julia George

Answer: If you're referring to the graphs that project a forecast temperature and heat index for about two and a half days in to the future, those are now available by clicking the "hourly forecast" link on our main weather page, and then scrolling down a bit to see the graph. The graph defaults to show hourly temperature and precipitation probability, but you can click a blue selector box at the top of the graph to choose between a number of other variables to plot. One of those is called "feels like," and shows the heat index or wind chill value, whichever is appropriate to the season.
Jul. 24, 2016 | Tags: apparent temperature, wral.com

Question: Sometimes the hour by hour forecast says there is 50-50 shot at storms but nothing happens. Is there a reason? — Amy

Answer: Part of interpreting a probabilistic forecast like that is keeping in mind both potential outcomes that are implied. In this case, over the period that you see a 50% chance of thunderstorms, you would expect that given the weather pattern in place, about half the time storms would develop and impact your area, and half the time they would not (and so, nothing happens). Another way to look at it is that if you have ten days with a stretch of hours having a 50% chance of storms, storms should occur on about 5 of those days sometime during the period of the 50% chance, and should not occur on the others. Likewise, a 30% chance of rain implies that there is a 70% chance that it will not, and so on.
Jul. 23, 2016 | Tags: maps & codes, thunderstorms, wral.com

Question: Do you have a clip of the radar view of the purple martins showing up on radar leaving their perch early in the morning? I think it was somewhere around Beaufort and it was the most amazing site on the radar. Just wanted to share it with friends. I saw it during the Saturday morning broadcast with Mike Moss. — Ginger Mangum

Answer: We don't have that particular clip, but you can usually see the expanding purple martin "roost ring" on radar starting around sunrise on radar loops from about mid-June through early September or so. The sites can vary a bit over the years - right now, the most visible is just south of the Pamlico River in Beaufort County, and it shows up best in lapses of the Morehead City NWS radar. Mike did a blog post about these roosts and their appearance on radar a number of years back, and you can still access it by typing "radar birds" in the search box on our site, which should turn up a link labeled "Radar that's for the Birds!" That post includes a radar still image that includes radar rings from three roosts that were active around southeastern NC that summer.
Jul. 22, 2016 | Tags: weather radar, wral.com

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