WRAL.com: Raleigh, Durham, Fayetteville

The most direct way to find your question is to search for the name you used when you submitted it (first name, last name or both). If you did not include a name, then you can search using keywords from your question. Of course, since many weather-related terms are common to a lot of the questions we receive, this may turn up a number of others in addition to your own.

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Answer: For Raleigh and most of central North Carolina, prevailing wind directions are from the southwest (from a compass direction of 230 or 240 degrees) ten months out of the year. The months of September and October are the exceptions, with a prevailing wind for those months from the northeast (030 to 040 degrees). Keep in mind that these are long-term averages, and there can quite a bit of short-term variability of wind direction in any given year.
May. 13, 2013 | Tags: normals, winds

Answer: One easy way is to just click on our "Almanac" link, where you will then see a drop-down date selector marked "Get Historical Data." Enter the date you're interested in, click go and you will see a page detailing that day's weather observations from the Raleigh-Durham airport. In the top section, there is a summary sections that includes the average wind speed for the day along with the highest sustained (2-minute average) and peak gust (instantaneous) speeds. Farther down the page you will find both a graph of wind speed and gusts, and then an hour-by-hour text listing that includes wind speeds and directions along with gust levels. Near the upper right hand portion of the page there is also a box where you can select a different location using an airport identifier (for example, KFAY for Fayetteville, KRWI for Rocky Mt-Wilson, KBUY for Burlington, etc). You can also change to a weekly or monthly listing for a quick one-page review of winds for many days at once.
May. 12, 2013 | Tags: cool sites, past weather, winds, wral.com

Answer: Ideal winds for an activity like kite-flying would lean toward those that are fairly steady over time, not too strong and not too weak (say a range of about 5-15 mph). One of the factors that would work against this, even in the case of otherwise steady winds, is turbulence. Turbulence can be mechanically driven, for example by wind blowing across a building or line of trees, or thermal, caused by pockets of heated air rapidly rising. In each case (or a combination) turbulent swirls and eddies can cause the air around the kite to suddenly flow up or down, speed up or reverse direction, all making control difficult. The sources of turbulence provide some clues as to the best overall conditions for flying - mechanical turbulence can be minimized by finding an open location with flat ground, while thermal turbulence can be minimized by choosing times when solar heating of the ground is reduced, for example on cloudy days or by flying before mid-morning or late in the afternoon when the sun is at a relatively low angle. Another thought regarding thermal turbulence is that you could sometimes minimize this by flying near shore in a seabreeze or lake breeze that would flow from water toward land from about mid-morning to mid-afternoon on bright, warm days that are otherwise lacking in winds. The air flowing in off the water should be relatively stable and turbulence free compared to that farther over land. If there are buildings or tree lines or other significant obstacles in the area, trying to ensure that you are located on the order of 10 to 20 times the height of the obstacle downwind will minimize the turbulent flow associated with those obstacles.
Apr. 16, 2013 | Tags: winds

Answer: Gusts have many contributing factors, but the more routine gusts that we experience on days with moderate to strong winds derive largely from the passage of turbulent eddies that result from mechanical and thermal mixing. Winds flowing across topographical or man-made obstacles develop vortices and rolls that can alternately oppose (and weaken) or reinforce and add to the mean wind as they travel past a point leading to rapid surges and lulls in the wind. If a passing eddie or vortex happens to be stretched along its axis as it moves along, it's rotation speed will increase even more, adding to the strength of gusts it may produce. Similarly, thermals (bubbles of air heated by the surface that become buoyant and rise) lead to upward motion and compensating downward motion that can capture air with greater momentum from several hundred to several thousand feet above the ground, and transport it rapidly to the surface where it can produce sudden increases in wind speed.

A somewhat different mechanism can be involved in the production of severe gusts of wind from some thunderstorms, in which heavy precipitation in the storm can drag air from above downward at rather high speeds, spreading out and producing strong horizontal winds that oftent take on a gusty character. This process is sometimes enhanced if there are layers of dry air being entrained into parts of the storm, or a layer of relatively dry air below the cloud base. In these cases, the precipitation may partially evaporate, cooling the downward rushing air, making it denser and increasing its fall speed - this is often a factor in severe thunderstorm wind gusts.
Mar. 24, 2013 | Tags: general meteorology, severe weather, winds

Answer: In terms of direct effects, wind of course will cause snow or rain to fall at an angle rather than straight down, so that if the precipitation is falling from a rather high-based cloud, it can change the location where the precipitation ends up reaching the surface. On a larger scale, wind patterns have an influence on the formation of rain and snow due to, for example, winds blowing across water bodies picking up moisture than can be transformed into clouds and precipitation, and in a kinematic sense, winds that converge toward a line or point in the lower atmosphere can force some of the air and the air above to rise (cooling it and potentially condensing out cloud droplets and precipitation). Similarly, winds in the upper atmosphere that diverge from a point or along a line can create a mass deficit that leads air below to rise, with similar results.
Mar. 11, 2013 | Tags: general meteorology, rain, snow, winds

Answer: This is a speculative answer, since we don't know any details of your location and the surrounding topography, but a good guess would be that you are experiencing some form of drainage wind, also known as "katabatic," in which air in contact with a cooling ground surface becomes cooler and more dense, resulting in a downslope flow. If there is a hill or mountainside somewhere close to you that is in a position to be among the first areas to start cooling noticeably via outgoing radiation as the sun sets, air descending that slope may cause the breeze that you are noticing in otherwise calm conditions. Under similar conditions, there would sometimes be a reverse, "anabatic" wind that flows upslope once the sun begins heating the same sloping ground.
Jan. 30, 2013 | Tags: fronts & airmasses, winds

Answer: It appears the term equinoctial gales arose in the mariner community and possibly derived from the experiences of sailors who encountered hurricanes or their remnants in the vicinity of the West Indies in September. In the mid-latitudes in general, there does not seem to be any real concentration of gale-force storm systems near the vernal or autumnal equinox, though outside of hurricane season (which includes the autumnal equinox), large, organized storms with gale-force winds are generally at a minimum in the summer and a maximum in the winter, with the equinoxes marking very roughly the time frame where they decrease in frequency in the spring and increase again in the fall. We would deduce that Doyle simply liked the sound of the phrase!
Jan. 21, 2013 | Tags: winds

Answer: You are probably thinking of the rough rule of thumb that winds tend to more or less flow parallel to isobars, which are lines of equal pressure. However, as with many rules of thumb and approximations, the reality is somewhat more complex. Winds would blow parallel to isobars if the isobars were straight lines, did not change with time, and there was no influence on the moving air from friction with the ground below. In the real atmosphere, winds at higher altitudes often conform reasonably well to this approximation, with some exceptions in strongly curved or rapidly changing isobaric patterns. However, near the surface, friction causes the actual winds to blow across the isobars at an angle which depends in part on the roughness and nature of the surface below, as well as on the curvature and rate of change of the isobar pattern. The net result is that northern hemisphere winds in the lower atmosphere (most often shown on our wind arrow/temperature projections) tend to flow clockwise around and outward from high pressure areas, and counterclockwise and inward toward low pressure areas.
Jan. 18, 2013 | Tags: coriolis, winds

Answer: In general, either level (and the 200 mb chart as well) will give a reasonable depiction of how the Jet Stream is organized, where it is located and how strong the winds are within the stream or its segments. It is true, however, that the height of the jet stream varies with latitude and with the average temperature of the air below jet stream level, so in a given situation, one of the chart levels above may come closer to intersecting the core of the jet and its highest wind speeds than the others. For that reason, if you are trying to conduct a detailed analysis of jet stream conditions, having a look at all three levels isn't a bad idea.
Jan. 16, 2013 | Tags: general meteorology, winds

Answer: You wrote on the evening of Saturday Dec 29, 2012. On that day we had a pair of upper level systems cross the area, the first creating areas of rain that diminished during the morning. A follow on system brought a surface trough and upper level front across the region during the late afternoon. By then, the atmosphere had become too dry for precipitation (so not much would be seen on radar), but rapidly cooling temperatures aloft destabilized the air enough to enhance cloudiness along a line that corresponded to the surface trough. This axis of instability also increased vertical mixing of the lower atmosphere, which helped to bring stronger winds to the surface. Winds were already increasing due to a tightening pressure gradient between low pressure leaving the area and high pressure to our southwest, and the added mixing brought wind gusts in the later afternoon and evening that reached around 30 mph.
Jan. 4, 2013 | Tags: past weather, winds