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Recent Questions

Question: I was wondering what are the oldest high temperature record and the newest low temperature record and what year, on average, was each type of record set for the entire year. — Michael

Answer: We're answering your question based on data from the RDU airport rather than a longer database that joins that data with reports from several other sites that served as the "official" Raleigh site back into the late 1800s, so that all the records would apply to roughly the same physical location. That being the case, we found that the oldest high temperature record still standing at RDU (where records began in the mid 1940s) is the 94 degree reading for May 21st, which was set in 1944. The newest low temperature record at the airport was the 32 degrees that was measured on October 19th in 2015. Assuming we interpreted the second part of your question correctly, we found the average year of maximum daily temperatures records for RDU to be 1987, while the average year of minimum temperature records is 1976.
Nov. 24, 2016 | Tags: past weather, records/extremes

Question: Why does your hourly forecast rain prediction (% chance of precip) not match the corresponding graph? — Nathalie

Answer: We assume you're asking about the first page that appears when you click on "Hourly" from any of our weather pages, or "View Hourly Forecast" just above the main 7-day forecasts display. If so, there is a list of hourly temperatures, sky condition symbols and precipitation probabilities, and then farther down the page is a graph with a box above it that allows you to select from several different variables to display. The default page for that graph shows traces of both temperature (in dark blue) and precipitation chance (in light blue). The code for that page is such that the values shown on the graph should match those in the hourly listing above. If you notice them showing different values again, please consider capturing a screen shot and noting the date and time so we can troubleshoot. Also, note that if the precipitation chance is zero, the light blue trace nearly blends in with the bottom of the graph. Do be sure to check that you weren't reading precipitation chances from the dark blue (temperature) line by mistake. The graph has a temperature scale on the left side and a precipitation probability scale on the right.
Nov. 23, 2016 | Tags: maps & codes, wral.com

Question: Should someone with asthma be outside tomorrow? Is this smoke danger what would cause difficulty breathing for them? Is there an alert out for this? — Judy

Answer: Unfortunately, this is the kind of question that we can't necessarily get to and post in this forum in time to address the particular instance being asked about. However, we wanted to pass along that there were some air quality alerts that stretched into central NC associated with smoke from the wildfires to our west, and that the concern was that those with serious respiratory illnesses, along with the elderly and very young children, should avoided strenuous exertion outdoors in those conditions. For anyone with questions about upcoming air quality issues, we maintain a couple of sources of information that can help. First, there's a link on our "Weather Resources" page (www.wral.com/weather/asset_gallery/13051669/) titled "NC Air Quality Forecast." Also, you can click the "Alert Center" link near the top of any page on our site, then click the "View active alerts" box to see every current weather or air quality alert in the state.
Nov. 22, 2016 | Tags: air quality, wral.com

Question: How do you see and report a fireball on 11/20 when today is 11/16? — Tim

Answer: That's a very good question, and the answer of course boiled down to a typographical error. The folks who wrote in to ask us about that fireball mis-typed the date. We were able to determine pretty confidently based on their description and the timing of their observation, that it matched up well with the fireball of late Saturday evening on November 12, as logged by the American Meteor Society at www.amsmeteors.org/members/imo_view/event/2016/4422. Our intent was to fix the date in the posted question, but after copying their question into the AskGreg database, we forgot to make that edit. We apologize for the mistake.
Nov. 21, 2016 | Tags: astronomy, cool sites, wral.com

Question: I have been watching you guys for 30 some years now. I love watching the weather because you are so accurate. My question is how do you think our Winter will look here in NC? I live in Fayetteville and was just wondering. — Jutta

Answer: We wish we could give you a good definitive answer, but seasonal outlooks by nature are quite general and somewhat low in confidence, and this year the signals that play into modulating our wintertime patterns are somewhat weak and mixed in nature. There is a weak La Nina pattern under way that appears it may weaken further and dissipate around mid to late winter. La Nina patterns tilt the odds toward an overall warmer and drier than normal result in our area, but is not a perfect predictor by any means, and also doesn't correlate very well in terms of seasonal snow which depends highly on short-term weather patterns and small variations in storms tracks. Another possible influence is the areal coverage of snow pack across Eurasia, which can affect the jet stream and resulting strength of the Polar Vortex. The snow cover is well above normal there this fall, which has been related to colder than normal winters for the northeastern U.S. - this effect is stronger off to our north, and leaves a lot of variability as to the results in central NC, so all we can really do is note that if La Nina dominates, we could well have a winter with temperatures a little warmer than normal overall, and perhaps somewhat suppressed precipitation, but even if this happens it tells us very little about how much snow or ice could occur.
Nov. 20, 2016 | Tags: el nino/la nina, winter weather

Question: Please explain why the Cape Fear did not have significant flooding from Matthew, while river basins to the north and South did. — Marsha O'Hare

Answer: We should start by noting that flooding along the Cape fear was quite substantial in some areas, especially southeast of Fayetteville and Elizabethtown. Most gauges from Fayetteville downstream recorded water levels that reached in the the "major flood" category, though for Fayetteville it was a brief excursion. On the other hand, a gauge just upstream from Wilmington recorded its second highest level historically. Upstream from Fayetteville, most gauges topped out for a short time in the moderate flood category. The rivers to the north and south in the Neuse and Lumber basins did have more extensive major flooding that lasted a bit longer. All of this relates to the shape of the individual watersheds and the pattern, or footprint, of the heaviest rainfall. Looking at contours of rain shows that while our entire region got very heavy rain from Matthew, in a relative sense some of the lower amounts fell near the headwaters of the Cape Fear, and along the Cape Fear basin as far east as about Fayetteville, with higher totals concentrated farther north and south in the adjacent basins. Those higher amounts did extend a bit into the Cape Fear basin from around Fayetteville eastward, helping to explain why major flood levels were more likely downstream as water in various tributaries collected into the main stem river.
Nov. 19, 2016 | Tags: flooding, hurricanes, past weather

Question: Does all the Hurricane Matthew runoff dilute ocean salinity? Does reduced salinity affect weather? — Chris

Answer: We took a look at salinity measurements from a couple of offshore stations in the period following Matthew and did find that there appeared to be a dip of around 1-2 Practical Salinity Units (PSU, from around 36 to 34) that was somewhat delayed, as you might expect from runoff that took some time to make its way from the areas that saw the highest rainfall totals. That dip was followed by a recovery to previous, pre-storm levels after a week or so, by late October. We suspect more notable decreases in salinity probably occurred in the sounds, but did not have access to similar salinity readings there. Generally speaking, less saline water is not as dense as saltier water and will tend to remain near the surface initially. In theory, this might reduce evaporation rates for a given temperature, and have some small effect on cloud formation or stability, but we doubt there were major changes in weather that resulted due to the temporarily lowered salinity values. It seems more likely that larger impacts from the Matthew runoff would have been biological in nature, especially in the shallower sounds where salinity changes, variations in nutrient levels and dissolved oxygen, and sedimentation from runoff would have been more concentrated and perhaps persistent. While updated info on these impacts from Matthew are not immediately available, significant impacts were noted in the wake of Dennis and Floyd in 1999, with salinity in the Pamlico Sound, for example, decreasing by about three-quarters, from around 20 PSU to 5 or so, for a couple of months following those storms.
Nov. 18, 2016 | Tags: Floyd, hurricanes, water resources

Question: How do I send you a weather photo? — Lyn

Answer: There are a couple of ways. When we see a question like this, we often write back and suggest simply responding to our e-mail with the image attached. You can also submit photos, videos and the like by going to the "Report It" section of our web site, where you can upload attachments. Just be sure to include in the text description that you'd like to have the image passed along to the WeatherCenter. You can jump to that section by typing "report it" into the search box in the upper right corner of any page on our site.
Nov. 17, 2016 | Tags: wral.com

Question: Did anyone report a meteor/fireball around 10:20 EST Saturday night, November 20? It moved south to north in the western sky,relatively slowly, and ended in a green fireball about half the size of the moon. So slow in fact that it could have been space debris. — David King

Answer: There were quite a few reports right in that time frame that are logged on the Fireball Reports section of the American Meteor Society web site. The address is
www.amsmeteors.org/members/imo_view/event/2016/4422, where you'll also find a "report a fireball" button at the top of the page in case you'd like to add your observations to the database. It seems likely this was a meteor, rather than a debris re-entry, unless it was an unpredicted re-entry not covered in the list at www.aerospace.org/cords/reentry-predictions/upcoming-reentries-2-2/.


Nov. 16, 2016 | Tags: astronomy, cool sites

Question: Could the Triangle be seeing a drier, warmer winter this year? — Stephen

Answer: There are some conflicting signals that make any confidence about how our winter will play out difficult to come by. It appears the Pacific favors a weak to near-neutral La Nina lingering into and through the coming winter. This weakly correlates to a higher than normal chance of drier than normal conditions for our area, as well as warmer than normal conditions, along the lines of what you noted in your question, but historically there is a good deal of variability in how winters turn out from one La Nina season to another. A different climate signal that has been in the news recently is the extent of Eurasian snow cover at the end of October, which has been linked to frequent cold outbreaks across the northeastern half or so of the USA, especially in the area of the Great Lakes and the northeast. This could be an indicator of some notable cold air outbreaks, though it doesn't do much to help determine whether we will happen to have significant precipitation during those episodes. We ran a very simple correlation of Eurasian snow cover versus seasonal snowfall, mean seasonal temperature and the number of days with an inch or more of snow at the Raleigh-Durham airport. The resulting correlation values suggested very little if any systematic relationship between October Eurasian snow extent and seasonal snow at RDU, a very weak correlation between greater snow cover there and cooler mean winter temperatures at RDU, and a small but positive correlation between that snow extent and the number of days an inch or more of snow occurred at RDU. Taken together, all that means we can't make any real definitive statement about how winter is likely to turn out.
Nov. 15, 2016 | Tags: el nino/la nina, normals, winter weather

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