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: There isn't a weather station we can check for an exact rainfall amount in your immediate neighborhood. However, there is a National Weather Service product that combines nearby gauge readings with radar-estimated rainfall amounts to make a contour map of rainfall amounts. We checked that map for your location and it gives an estimate of roughly 6-7 inches for May 2012. The contours indicate that rain in your area was little higher than right around Goldsboro itself, and three stations in the Goldsboro vicinity showed rain for that month of 5.05", 4.23" and 4.53". There is also a volunteer precipitation reporting site several miles east of Goldsboro that reported 6.85". That's about as much as we can check from here, and seems to indicate that you had a very rainy month, but more than likely not quite to the level in your charts. Of course, in situations involving heavy or convective precipitation, there can be large differences in rainfall over short distances, so we can't completely rule out that 11-inch value.
May. 16, 2013 | Tags: past weather, rain

Answer: You can check all that for a single site (the RDU airport) right on our web site. Just scroll down to the "data" section of our main page, find the "Historical" column and click the "RDU Rainfall" link. There you'll see accumulated rain versus normal for several different time spans, and above the graphs there is also a selection box you can use to access some other ways of viewing the rain, including a 50-year span of annual totals.

When you're more interested in how rain has varied across the region, you might like to check out the National Weather Service precipitation analysis page at water.weather.gov/precip/. There's lots to explore at that page. To zoom in to central NC, just click the "NWS WFOs" radio button under "location" and select Raleigh. Turning on the county line overlays can also help in orienting yourself. Here you can plot contours of observed rainfall over varying period, or compare the rain to normal by way of anomalies and percentages of normal precipitation.
Apr. 15, 2013 | Tags: cool sites, past weather, rain

Answer: This was a new piece of weather folklore to us, but we did find just a couple of isolated mentions of something along these lines in a quick web search. On the other hand, we also turned up an old English rhyme that stated "If a cat washes her face over her ear, 'Tis a sign the weather will be fine and clear," showing that the same feline behavior seems to have been interpreted to have opposite meanings. We can't think of any reason why either of those would successfully predict rain, or a lack thereof. There are a few of the old weather "wives tales" that have an underlying grain of truth or physical reasoning behind them, but many do not and it can be difficult to understand how they initially came to exist.
Apr. 14, 2013 | Tags: folklore, rain

Answer: That is not only possible, but has happened many times in our area due to the fact that we are often on the borderline for transitions between different precipitation types. In addition to having rain and snow (and sometimes sleet and/or freezing rain as well) in the same day, it is occasionally the case that a mixture of rain and snow can fall at the very same time in the same location. Usually this only occurs for a fairly short time before changing to either all rain or all snow.
Apr. 12, 2013 | Tags: general meteorology, rain, snow, winter weather

Answer: There are a few things that play a role in this. Of course raindrops and the rainwater itself typically would be odor-free, but that is not the case with materials that may exist on the ground or on other surfaces that the rain drops fall onto. The most common odor associated with rain is produced by spores from a microorganism in the actinomycetes family, which develop during dry periods and are splashed into the air in the form of a fine aerosol when rain begins. This odor actually has a name, "petrichor," and is a kind of dank, woodsy smell. There area sometimes also aromas associated with the rain falling on roadways and lofting bits of tires and petrochemicals into the air, and finally, when thunderstorms are nearby there can also be a faint odor of ozone, which is created along the lightning channel and has a sharp, somewhat chlorine-bleach-like character. Under the right circumstances, the wind can carry some or all of these odors ahead of a moving area of rain, giving an olfactory alert that precipitation may soon begin!
Mar. 31, 2013 | Tags: folklore, rain

Answer: The radar return by itself actually can not tell us with certainty what kind of precipitation is occurring at the ground, so there are a number of techniques that have been applied in radar display software over the years to color-code echoes to show the estimated precipitation type at the surface. This has usually been done with an algorithm that combines nearby recent surface observations (precipitation type and temperature) with data collected from sounding balloons or aircraft, and also considers computer model projections and/or analyses of the vertical temperature and moisture structure of the atmosphere. By using all these inputs, a reasonably good selection of precipitation type can be made for most areas, but it is not a perfect solution and has to be treated as an approximation.

Newer radars with dual-polarization capability, such as our Dual Doppler 5000 and recent upgrades being installed at National Weather Service sites, do have some capacity to more directly make those determinations. The precipitation type being sampled by the radar beam can be reasonably well estimated based on several parameters measured by the combination of horizontally and vertically polarized signals, but is subject to some ambiguity. In addition, while dual-polarization is pretty good at estimating the type of precipitation at the height of the radar beam (which increases with distance from the radar site), it can not determine whether that precipitation type changes between the altitude sampled and the ground below, so combining the dual-pol technology with the other methods mentioned above is usually a good idea.
Mar. 29, 2013 | Tags: rain, snow, weather radar

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: In recent weeks we've transitioned to a pattern that features more frequent development of upper level troughs to our west, which then generate low pressure waves at surface that travel along fronts moving through the region. All of this has made rain and occasional wintry precipitation more common than it had been (but not to 40 days & nights magnitude!). Before we launched into this pattern, parts of the area were in moderate drought, so with any luck the wetter period will help get us back to more normal levels of soil moisture, stream flows, reservoir volumes and groundwater status.
Mar. 3, 2013 | Tags: rain, water resources

Answer: We can only surmise that you've been a little unlucky with respect to being in the right place and time to see rainbows for a while, as the conditions that lead to them haven't really changed all that much and they continue to be frequently seen and photographed. The basic ingredients for seeing a nice rainbow are for the sun to be fairly low in the sky, for there to be some breaks in the cloud cover on the side of the sky where the sun is located, and for there to be some rain falling on the opposite side of an observer from the sun, with the rain illuminated by direct sunlight. For much more on rainbows, see www.atoptics.co.uk/bows.htm.
Mar. 1, 2013 | Tags: atmospheric optics, cool sites, rain

Answer: You didn't say exactly where you were, but as you imply most of the time if rain falls into a layer of air near the ground that is as cold as 28 degrees, elevated objects and even some surfaces in contact with the ground will develop a glaze of ice. However, there are many variables that can play a role. As you mentioned, the temperature of the air can vary greatly with height, and it is possible you were seeing rain that fell through a very warm layer before reaching the surface. This can delay freezing as the raindrops may carry some of their heat to the surfaces in question. There can also be a question of how long the air temperature has been at 28 degrees - if it was a rapid drop, then the cars and concrete may still be at or above freezing. The duration and intensity of precipitation can also play a role - usually, if the air temperature remains below freezing and the precipitation continues, eventually most objects will cool enough to begin to accrue a glaze of ice.
Jan. 31, 2013 | Tags: rain, winter weather