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Weather Questions tagged “folklore”

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Question: I'm currently having problems with my T.V. and computer. Is there any way to receive a forecast on my phonograph? — Hugh M

Answer: We probably shouldn't take the bait here, but nonetheless will suggest that it may be possible, on days with a record high.

We now return you to our regular programming...
May. 18, 2017 | Tags: folklore

Question: What can you tell me about Chemtrails? Do you believe we are being sprayed with chemicals? I watch the skies sometime. I am beginning to think this is true, particularly if you watch the streams and the pattern of the flights. Many patterns. — Charlotte Carlton

Answer: There are quite a few web sites and videos that posit a theory that a secret program to alter the climate, depopulate the planet or somehow control people through emission of chemicals is evident in the appearance of long white trails behind high-flying aircraft. However, pretty much every photo and video of the trails, the sky or the lingering cirrus cloud cover on these sites seems to show images of routine contrails (condensation trails), the likes of which have existed since the beginning of high-altitude flight operations. We've delved into this several times in the past few years on AskGreg, and rather than repeating the details here, you can look through those earlier responses by using the search box at the top of the list of AskGreg questions. Just type in "chemtrails" or "contrails" and press "enter" to turn up those answers.
Apr. 5, 2017 | Tags: air quality, controversy, folklore

Question: On Saturday we had a thunderstorm, and I asked you about the chances of frozen precipitation within seven days. So, today is Tuesday, and we had hail. It was not what I expected, but it was definitely frozen, and it's appearance fell within the prediction of "Thunder in the the Winter". Old wives' tale wins again. — John

Answer: Good observation, though it may be pushing the connection just a little! We've always heard the old rules of thumb as specifying "snow" within 7-10 days of a wintertime thunderstorm, which seems more meaningful in the sense that thunderstorms are just as capable of producing hail in August as in February or March, while we are extremely unlikely to ever have a thunderstorm followed by snow a week or so later during the summer.
Mar. 28, 2017 | Tags: folklore, snow, thunderstorms

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

Question: Please please answer my question. I have always known full moon is end of month. Why are we now having full moon around the middle of the month? — Patricia Pender

Answer: We're not sure how the idea that full moons should only occur at the end of months has gotten around, or exactly how pervasive it is, but we've gotten a few questions to this effect recently. Full moons have always been able to occur at any time of a month, and are not restricted to the end of months. Keep in mind that the lunar cycle is such that the moon's orbit puts it into position for a full moon about every 29.5 days, while the length of months varies, mostly between 30 and 31 days, but also with February at 28 (and sometimes 29) days. So, typically the timing of a full moon will move back (earlier) by about a day or so each month. In rare months, a full moon occurs both right at the beginning of the month and another right at the end, giving us two full moons in a single calendar month. In modern times, the second of those has come to be known as a "blue moon."
Feb. 21, 2017 | Tags: astronomy, folklore

Question: Saturday morning (2/11/17) at sunrise, the eastern sky was an intense red and blue. After several minutes, the entire sky was red and blue. It only lasted about 5 minutes then faded. What causes this? How does this fit into the old saying of "Red sky in morning, sailor take warning." — Scott Livesey USN (Ret)

Answer: The conditions that led to the nice colors you noted basically boiled down to the right kinds of clouds in the right places. We had some upper-level moisture flowing in from the northwest, with the airmass being lifted some due to flowing across the mountains to our west. The resulting clouds covered a good portion of NC, but did not extend very far to the east. The base of the clouds was around 20-25,000 feet above the ground, so that when the sun was very low in the sky around sunrise, it was lighting up at least some of the clouds in this area from below. The direct light from the sun was strongly colored red due to preferential scattering of the blue end of the spectrum removing many of the short wavelengths and leaving mainly the red and orange end of the spectrum to strike the clouds. On the other hand, any portions of the cloud that were blocked by either the horizon or by other clouds from receiving direct sunlight were lit instead by some of the scattered light, which is predominantly blue in color. The effect is often rather fleeting, as the sun continues to rise, with its light quickly becoming less filtered and less reddened as it gains altitude. As to the "red sky at morning" rule of thumb, it arises from the idea that the typical west to east motion of midlatitude storm systems can leave the eastern horizon clear in the morning, while an approaching storm from the west may first produce some high cloud cover overhead that can be reddened in the manner that you saw. If this is the case in the morning, then a system approaching from the west may arrive later in the day, with lowering clouds, precipitation and perhaps increasing winds. On the other hand, if the western horizon is clear at night and there is a dry high pressure area approaching, clouds overhead associated with a departing storm system to the east may be reddened by the low sun in the west, and with those clouds and the associated storms system pulling away to the east, sailors may take "delight" in fair weather to come. While this is the physical basis for the old saying, the atmosphere is complex enough in reality that the saying will prove true at times, and will be unfounded at others. In the case of Saturday morning, the nearest significant storm system was passing by well to our north, and the high clouds we saw here at that time were associated with the upper moisture crossing the mountains rather than with an approaching low pressure system that would bring active weather a short time later.
Feb. 16, 2017 | Tags: clouds, folklore, general meteorology

Question: I live in The Villages, Florida and it appears that weather, particularly thunderstorms, tend to go around the Villages. We don't get as much rain as the surrounding area. I am told that radiation from the roofs of 50000 closely packed homes can affect weather patterns. — Barry Connell

Answer: It's certainly the case that the character of the surface can impact the lower atmosphere and therefore weather patterns in any given location, especially in the way of microclimates. However, it can be difficult to attribute something like the sense of storms going around a given location to a particular cause without a very detailed investigation. More commonly, there is a perception that storms often go around any given point because of the frequently scattered distribution of thunderstorm cells and clusters, their rapid variability in terms of size and intensity, and the tendency for radar depictions of those storms to make them appear to cover more area than they really do. We find here in central North Carolina, that people from almost every part of our viewing area perceive that storms preferentially split or dissipate when approaching their location, and reform farther downstream. We did note than in the Florida peninsula, there is a drier axis that stretches from a little north of your location all the way to the southern end of the state, with higher average rainfall closer tot he coasts to either side. We suspect this is a reflection of thunderstorms that often form along the sea breeze, progress inland and deplete some of their initial moisture and energy before reaching the interior sections of the state. For someone centrally located like yourself, this could result in a number of times when storms approaching from either the east or west would diminish in coverage before arriving.
Aug. 9, 2016 | Tags: folklore, general meteorology, thunderstorms

Question: When is the thermal Equinox in Raleigh? — Don Wollum

Answer: We aren't aware that there is a physical or statistical property called thermal equinox, and the only thing that turned up in a web search was someone's informal, kind of joking, definition on a chat page. That being said, we wonder if you're looking for something along the lines of that person's take on the term, which was the halfway point during the year between warmest and coldest average temperatures. If that's what you had in mind, then for Raleigh those points come on April 16th and Oct 18th, when our average temperature is closest to 60.4 degrees. This number arises from splitting the difference between our warmest average temperature of the year (80.3, which occurs July 14-17) and our coldest (40.5, which occurs from January 5-12).
Jul. 21, 2016 | Tags: folklore, normals

Question: I was searching some weather facts and I found this: (not sure how realistic this is... On this date (April 16, 1851) The Famous Lighthouse storm hit Boston Harbor, MA. Said it destroyed the Minot Lighthouse and its keepers and the tide exceeded a staggering height of..get this...1,723 feet??? really??..I'm not sure a cat five hurricane and two 8.o magnitude earthquakes at the same time could do anything like that... so is this real..or really been told a loooottttt of times and you know how those things go. — David

Answer: We appreciate you calling our attention to an interesting story about about an intense nor'easter that swept the Massachusetts coast in April of 1851. This occurred Just four years after the start of construction on Minot's Ledge Lighthouse, and only about a year after it was completed, and resulted in the toppling of the light and loss of two assistant keepers. Strong nor'easters and tropical cyclones tend to lead to the highest tides in the region, and the 1851 event is one of the highest on record for the area. However, as you surmised, 1723 feet would be an impossibly high surge, or storm tide level. We think you misread a date as a tide level in this case, since the 1861 storm, which resulted in a storm tide that reached about 10.4 feet above mean sea level, was remarked upon at the time as the highest water seen since a powerful February nor'easter produced a storm tide of about 11.4 feet in the year 1723.
Apr. 22, 2016 | Tags: flooding, folklore, past weather

Question: Over the Christmas holiday, we had several claps of thunder with lightning. Everybody loves to say, "Thunder in winter means snow in 10 days (number varies)." I recall that you explained the science behind this old saying. Would you mind sharing it again? — Liz

Answer: As you noted, there is some physical reasoning behind that old saying. It doesn't make for all that reliable a predictor, but 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.
Dec. 18, 2016 | Tags: folklore, snow, thunderstorms

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