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Question: Why is it that sometimes the high for a day on the WRAL weather site will be listed as a very different high compared to finding the high through the hourly readings? One example, the high on 3-21-2017 is listed as 80, but scrolling through the hourly temps the highs never exceeds 75. Thanks for the most interesting and accurate weather forecasts. Our family likes watching WRAL weather. — Aylin Regulski

Answer: We appreciate the kind words, and having your family as viewers! There are a couple of things that can contribute to the issue you asked about. First, the highest temperature of the day can occur between hours, so that on occasion any two hourly times may bracket the time of the maximum value. This would usually only result in a difference of a degree or two, though. A more pertinent factor is the manner in which our web site is set to retrieve hourly forecast information. While the main 7-day forecast numbers (highs/lows), weather icons, wind speeds and directions, and text descriptions for the Raleigh area are directly entered by WRAL WeatherCenter meteorologists, the hourly values, in addition to 7-day forecasts that you might use the "change location" feature for, are retrieved from a gridded information resource called the National Digital Forecast Database (NDFD), which is populated through a combination of computer modeling and adjustments by National Weather Service meteorologists. At the time you checked the hourly forecast, that database was indicating a max temperature in Raleigh for that Tuesday around 77 degrees while we were projecting around 80 (of course, while we have to choose a single number for the 7-day forecast, we would not have been surprised at the observed high ending up anywhere in about the 77-83 degree range, as alluded to by the written description portion of our forecast, which called for highs in the "upper 70s to low 80s" - the actual high observed at RDU that day turned out to be 82). Use of the NDFD allows us to include the ability for you to use the "change location" function on our main weather page to check forecasts for distant locations in our state, or anywhere across the United States.
Mar. 23, 2017 | Tags: maps & codes,

Question: During the storm this evening, the sky had an orange appearance, and then yellow. What causes that? — Pat Kowite

Answer: You were likely noticing the effect of the cirrus outflow clouds from the upper portion of the thunderstorm reflecting light from the setting sun. The timing of the storm was right around the time of sunset, and with the sun near or below the horizon, it's light is turned yellow, orange or red somewhat due to the blue end of the spectrum being scattered out be air molecules (sunlight passes through a lot more air when the sun is near the horizon than when it is high in the sky). When this warmly colored light illuminates the base of those thunderstorm anvil clouds, it produces the slightly eerie coloration that you reported.
Mar. 22, 2017 | Tags: atmospheric optics, thunderstorms

Question: There seems to be general dissatisfaction with the twice-yearly time changes -- serving little or no purpose for energy savings and being disruptive to people. Who or what body has the power to discontinue the national time changes? — Robert Weickert

Answer: Under existing national legislation, the dates of time change are set for the country as a whole, but individual states do have the option to draft legislation that opts the state out of switching to DST. Currently, Hawaii and Arizona do not switch to daylight time, and remain on standard time year-round. In that sense, the most direct means for you to lobby in favor of not changing the clocks twice a year would be to contact your state representatives and or state senators and ask them to push for legislation opting NC out of DST. Alternatively, you could make the same suggestions to your congressman or U.S. senators in hopes that they will push for changes to the national time legislation. The problem that seems to arise in switching to a single year-round time is that some people would rather that be standard time, while others would prefer DST, and a legislative stalemate ensues. There have also been suggestions to simply abandon time zones and have everyone switch to using Universal Time (meteorologists use this for weather observations, satellite data times, radiosonde balloon launches, computer model times, etc in order to maintain worldwide coordination), which has the advantage of 1030 or 1345 hours, for example, referring to the same moment in time whether you happen to be in Raleigh, Denver, London or anyplace worldwide.
Mar. 21, 2017 | Tags: maps & codes

Question: How do wind gusts (of 40 mph) impact flights? — Monique May

Answer: Flights are affected by gusty winds to varying degrees and in different ways depending on the phase of flight, the size and type of aircraft and in some cases the direction of the winds. When aircraft are in steady flight at fairly low altitudes, strong gusty winds can lead to a bumpy ride due to the turbulence involved, which causes sharp upward and downward motions in addition to the rapid increases and decreases in horizontal wind speed. Gusty winds can be more of an issue when an aircraft is in takeoff or landing mode. If the winds are blowing along the direction of the runway, sudden surges or lulls in wind speed can cause sudden changes in the effective airspeed of the plane, causing lift to be suddenly gained or lost (potentially leading to stalls), and there are techniques pilots can use to anticipate and partially offset these effects (such as adding part of the difference between steady winds and gust speeds to the approach or takeoff speed that they use). If the wind direction is largely perpendicular to the runway, strong gusts can cause sudden variations in the crosswind speed, making it difficult to remain properly lined up for takeoff or landing. Winds gusting beyond the crosswind limits of the aircraft can lead to aborted landings and go-arounds, and if they are persistent enough, can force the pilots to choose to proceed to an alternate airport where winds are lighter or are more favorably aligned with the runway.
Mar. 20, 2017 | Tags: weather & health, winds

Question: I have to know the answer,and I always heard when you don't know..ask a pro, so here goes. Why don't we get those "old timey electric storms" like we use to get 35 yrs ago when I was a kid? You know,those bad storms where the sky would get black, sharp lighting that use to strike everything like houses, trees, the ground, antennas, even people, and the thunder would be so loud it would rattle the pictures on the wall and usually the lights would go out. So..why don't we get those kind of storms here anymore? — Archer5

Answer: While the number, frequency and intensity of thunderstorms certainly varies a good bit from year to year in a given location, we aren't aware of an overall trend toward fewer of them in our state, and it remains the case that there are occasions when storms here produce especially copious amounts of lightning. In fact, in recent years the local National Weather Service office in Raleigh has carried out an interesting research program to develop better methods for identifying days when storms are like to produce "excessive" lightning. We can't be certain, but we would guess that like ourselves, your perception may be based on how much more intense an experience like a heavy thunderstorm seems when you are very young, along with the fact that nowadays we tend to know more often when storms are coming, how long they will last, etc, and unless they happen to be severe cells that produce damaging winds or tornadoes, they don't carry quite the same sense of awe that similar storms might have when we were small children.
Mar. 19, 2017 | Tags: lightning, thunderstorms

Question: I have a small organic vegetable farm and could use a good home weather station. Can you folks recommend a good home weather station? I would like to track daily precip, temp, pressure, etc. It would be nice to be able to download the information to a spreadsheet so that I could look back at things over time. — David Higginbotham

Answer: There are several reputable companies (Davis, La Crosse, Rainwise, Acurite, Oregon Scientific, etc) that make complete home weather stations that range from quite basic to to very advanced (and from inexpensive to rather costly as you move up the quality/accuracy/convenience scale), to include wired or wireless installations and data transfer. Most include software for archiving and displaying the data on a PC, tablet or laptop, which would serve the function you mentioned regarding looking back at the history of your site. You can find a number of suppliers for these systems by doing a web search for the phrase "home weather station," and most of the sites include customer reviews that may help you decide on the system best for your farm. We would recommend going with one that falls in the "complete" category, so that it includes instruments to measure wind and precipitation.
Mar. 18, 2017 | Tags: instruments

Question: I work for the Town of Fuquay-Varina and I was wondering what it would take to set up a WRAL weather station here in one of our downtowns? Thanks! — Matthew

Answer: We weren't quite sure if you are asking about one of our SkyCams or if you meant you'd like to have a weather station that we can tap into to show current temperatures, wind or precipitation totals. So, we'll provide some information about both here.

Our SkyCam network requires a particular brand of camera, and we’d be happy to provide you with specifics on what some other towns have installed to become SkyCam locations. We can provide some installation assistance as well, if needed. We're contacting you separately by e-mail to keep the process going, and invite other towns that are interested to contact us as well. We do have new SkyCam sites in the works for a couple of other local cities.

As for weather readings, the majority of stations we plot in our on-air graphics are official sites operated by government agencies like the NWS, FAA, State Climate Office of NC and so on. However, there are a few sites we show that are part of the "Meteorological Assimilation Data Ingest System" (MADIS) that also incorporates some stations that are part of the "Citizen Weather Observer Program" (CWOP). While we can't guarantee whether we'd show your data, we'd be happy to have it as an option from the MADIS database. You can get more info on becoming a contributor to that by checking the information at (see "Becoming a Provider" which includes a link to CWOP (where you'll find a "Join" link) and an alternate contact link in case you encounter any problems with the CWOP process. There are also a couple of helpful documents on getting connected as a Davis Instruments station owner, at and Once you become a provider for CWOP and MADIS, feel free to contact us through the "feedback" section of our web site and let us know where your station is located and what your assigned identifier code is (typically, this would be a unique 5-character combination of letters and numbers). That will make it available for automatic plotting and updates on our maps if we choose to use it. Thanks for checking with us, and good luck!
Mar. 17, 2017 | Tags: instruments, maps & codes,

Question: I know we've had warm springs and cold springs in the past... but have we ever had pollen and snow at the same time in Raleigh? — Mira Abed

Answer: We doubt the combination that occurred the weekend of the 12th is very common, but it's a little difficult to check as historical pollen readings more than about ten years back are not as readily available as snow observations. We did quickly find that some measurable snow in early March 2009 corresponded to the dates of moderate concentrations of tree pollen, but the species listed were juniper and elm. While these pollens can aggravate allergies in people who have them, they are very fine grained and we usually don't notice them visually the way we do the larger yellow pine pollen grains, which were active at the time of our recent snow. We suspect that if we had more access to long-term pollen data, there would also be a couple of other rare periods when snow and pine pollen also occurred around the same dates.
Mar. 16, 2017 | Tags: past weather, pollen, snow

Question: Any chance this weekend will be like the weekend of march 11, 1993? — Paul Morgan

Answer: Due to the delay of a couple to a few days between answering these questions and the time they show up on the site, the weekend you were asking about is already over, and as expected the snow-producing upper level disturbance that brought anywhere from nothing to a little over an inch of snow to our part of the state on Sunday, March 12 was very different from the "Superstorm" of March 1993. Oddly enough, given the monster storm that one turned out to be, we actually had almost as much snow here in central NC from the modest system that passed through over the weekend as from the 1993 event. Back then, the surface low with that system followed a somewhat inland track up through the southeast U.S. compared to many nor'easters, and in the process kept temperatures warm enough over central NC that only about a half-inch to two inches of snow occurred in the Triangle and nearby areas, with just a trace to the south and east. On the other hand, that storm remains a record-setter for western NC, and some of the higher elevations in our mountain counties got as much as 40-50 inches, compared to anywhere from a trace to about 4 inches this past weekend. You can see a map of snow totals in our state from the March 1993 storm at
Mar. 15, 2017 | Tags: past weather, snow

Question: How many times has it snowed 14 days after a thunderstorm as the old wives tale say? — Sue Jimenez

Answer: We'd usually heard that saying using 10 days, or sometimes "within ten days" as the time frame involved. Nonetheless, while it doesn't make for all that reliable a predictor, there is some truth to the idea that snow is more likely when we have recently had a pattern that produces wintertime thunderstorms. This has to do with the same kinds of very wavy (we call them "meridional flow") upper-level patterns being able to both pull warm, moist air into the region from the south to fuel instability and storms with lightning, and as the waves move along, subsequently being able to draw cold air from the north far enough south to give us a chance at wintry precipitation. When we are in patterns with flatter, generally west to east, upper-level winds (called "zonal flow"), we may have some cloudiness at times and occasionally some rain or light showers, but in that pattern our temperatures don't tend to stray too far above or below normal, and we rarely have thunder or snow.

A while back, we worked with the State Climate Office of North Carolina to look into some statistics relating to this old "rule of thumb," and found, for example, that on any given day in the winter at the RDU airport, there is about a 1 in 16 chance that snow will occur in the window of 7-10 days later. On the other hand, for a day when thunder is observed, the chance of snow 7-10 days later is about 1 in 8. So, the occurrence of thunder in the winter appears to roughly double the chance that snow occurs in the next 7-10 days. However, that chance is still low enough that many times it will not happen.
Mar. 14, 2017 | Tags: folklore, lightning, snow

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