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Question: I live in Raleigh and am building homes in Fuquay. I am trying to find the map with rainfall totals for various cities and have searched your site. I cannot find it so I will have to go see how much mud is in the bottom of my footings. How do I find this chart that was once so simple to find? — Anonymous

Answer: The 24-hour rainfall totals map that your asking about was removed from our web site for a while due to a change in the manner in which some of the data is accessed and maps are plotted. however, we expect it to be back soon, possibly by the time you read this. At that time, it should again be available in our "Map Center" section. We can suggest a couple of alternative sources as well, especially if you're interested at times in longer period totals or comparisons to "normal." First, for a simple 24-hour map of precipitation ending around daybreak each day, see the "precipitation" tab at www.weather.gov/rah/dailymaps. There is also a map of 24-hour precipitation available at water.weather.gov/precip/ that can be displayed in a variety of ways using the control panel below the map. In addition to the 24-hour rain estimate, based on a combination of rain gauge and radar measurements, the data can be plotted for a number of time spans (7-day, 30-day, etc) and can be plotted as a difference between observed and normal amounts, or a percentage of normal, for each period.
Feb. 8, 2016 | Tags: cool sites, past weather, rain, wral.com

Question: What's the difference between snow flurries and snow showers? I have always thought it was snow flurries, and rain showers. — Frederick C.

Answer: The essential difference is one of intensity. In both cases, the snow is expected to occur in start and stop, off and on fashion, with rather variable intensity. In the case of snow showers, the intensity may be great enough to cause notable accumulations if the showers are sufficiently frequent and persistent. Flurries can be thought of as a subset of snow showers, those in which the intensity is very light, and from which accumulating snow is usually not expected. In a warmer situation when only liquid precipitation would be expected, one could similarly refer to sprinkles and rain showers.
Feb. 7, 2016 | Tags: general meteorology, rain, snow

Question: What was the temperature range in Cary, NC from 12/17/15 - 1/20/16? — Joann Martin

Answer: We checked for the warmest and coldest temperatures reported at two personal weather stations located in different parts of Cary, as well as the official readings from the Raleigh-Durham airport for the period of dates you asked about. We found during that time that the Cary stations reported maximum temperatures as high as 77 and 79, respectively, while the RDU airport reached 77 degrees for its maximum reading. As for the coldest temperatures during the period, the two Cary stations both dipped as low as 19 degrees, while RDU reported a minimum temperature of 18 degrees.
Feb. 6, 2016 | Tags: past weather

Question: Why did the snow storm last week in Washington and New York area have a name (Jonas) like hurricanes? — Marilyn Farmer

Answer: One media company (the Weather Channel) decided leading into the 2012-13 winter season to start naming winter storms for purposes of their broadcasts. This differs from tropical cyclones, which are named by committees of the World Meteorological Organization, with those names recognized and utilized in an official capacity by government organizations such as the National Weather Service and National Hurricane Center. Government organizations and most other media sources (including WRAL) do not currently use names for winter storms.
Feb. 5, 2016 | Tags: controversy, hurricanes, winter weather

Question: I seem to be one of the few people that actually like it pretty cold. It's almost the beginning of February and it's getting close to 70 degrees! I can't believe it! It does look like the temps are going to drop again by next Saturday though. In your personal opinion, do you think there is any chance we'll have some more snow before spring? — Yuki

Answer: By the time you read this, a cold front should have begun to spread chiller air back into the region, and it appears we'll stay seasonably cool for the most part out through mid February. With a very strong El Nino still in force (albeit on a slow weakening trend now), our prospects for more than normal precipitation should remain fairly high through the remainder of winter. We'd expect there's a chance of more measurable snow as we go along, but there is simply no way to be certain about that, as it depends so heavily on the particular arrangements of cold air, moisture and lift as each storm system traverses the area. These factors can only be forecast with any confidence a few days in advance.
Feb. 4, 2016 | Tags: cold, el nino/la nina, snow

Question: How does a layer of ice cling so fiercely to my car's windshield? — John Coppersmith

Answer: The underlying reason for this is a property of water called hydrogen bonding, which leads water to become more or less spherical or to bead due to surface tension when it is in suspended in the air or in contact with hydrophobic surfaces like certain plants, waxes or oils, but conversely causes it to spread out onto and "wet" certain hydrophilic surfaces. In contact with such surfaces, ice can be a very sticky substance. Unfortunately on cold, humid mornings or in ice storms, clean glass is such a surface, having numerous hydrogen-oxygen groups that are highly attractive to the hydrogen bonds in water. This can be seen when liquid water encounters clean glass, in which case it will spread out into a thin film and stick to the glass. When there's a lot of it in smooth contact with glass and it is also frozen solid, the molecular bonds between glass and ice are similarly strong, but you also add the strength of the bonds within the sheet of frozen ice itself to resist the efforts of a person trying to scrape the ice off. Of course, as the temperature of the glass and the interface between the ice and glass approach and exceed the melting point, it becomes easier to overcome those bonds and remove the ice. There are products designed to spray or wipe on windshields to prevent or minimize the ice/glass bond from forming and to make it easier to remove frost or glaze ice.
Feb. 3, 2016 | Tags: dew/frost, winter weather

Question: What is the bright star in the eastern sky down low? — Charles Suit

Answer: We assume you're asking about the very bright light near dawn in the east-southeastern sky in the morning. If so, you're seeing the planet Venus, currently located along its orbit so that we see it just before sunrise, when it is often referred to as the "morning star." At other points along its orbit, it can be seen in the western sky in the hours just following sunset instead, in which case it is often referred to as the "evening star." In either position, it is very noticeable due to being the brightest object in the night sky apart from the moon.
Feb. 2, 2016 | Tags: astronomy

Question: Because trees/branches weighed down with ice is our major source of power outages, is there a brine solution that could be sprayed on branches near power lines to prevent that or would it be fatal to the trees? — Tim

Answer: We suspect that most brine or other anti-icing solutions would be impractical for application to trees for a few reasons. As you noted, most that concentrated enough to prevent accumulation of ice would likely be harmful to the trees. In addition, freezing rain sometimes begins as rain, which would wash the solution off the branches, needles or leaves before it could do its job. It is also the case that the exact locations of significant freezing rain are difficult to pin down in forecasts, making it very possible that extensive application of a solution would often be done in the wrong locations. It seems likely as well that it would be much more labor intensive and expensive to apply effectively to trees, when compared to application to road surfaces. Instead, the usual approach of power companies is to carry out programs of tree trimming to reduce the amount of impacts falling or drooping trees/branches will have. Of course, in fairly widespread icing scenarios, even these preparations often yield to the fact that every possible conflict between trees and lines can't be resolved or prevented. Of course, when the ice becomes thick enough, lines can be affected directly such that their own weight, causes transformers to trip or lines to arc or even snap. We suspect that if lines could be treated or manufactured with a coating that would prevent ice accretion, they already would be.
Feb. 1, 2016 | Tags: winter weather

Question: Just wondering the similarities with this storm compared to the January storm of 2000 where we had 18 inches in Wake Forest. Also thank you for keeping us informed and the hard work and long hours your team does for us. — Nathan Redinger

Answer: There were certainly similarities and themes in common that many winter storms that evolve into powerful nor'easters share, but in looking over some surface, mid-level and upper-level analyses through the course of each storm, a couple of things stood out. In 2000, there was a stronger upper level ridge over the northern plains that led a deepening upper level trough (and eventually cutoff upper low) to move into position much farther southeast than one the deepened into a cutoff low over the Mississippi and Tennessee Valleys areas this time. Corresponding to that, an initial primary surface low this year formed well to our southwest, over LA, then was steered northeast to eastern TN where it weakened as a secondary low formed near the NC/SC coast. This "energy transfer" from an inland low to a coastal storm is called a "Miller Type B" pattern. The 2000 storm, given the more southeastward push of the upper trough, saw a single primary surface low develop over FL and track north/northeast along the coast, where it explosively deepened as it moved along our coast. This type of pattern, involving a more defined single intensifying surface low, is called a "Miller Type A." While all storms have their complexities and can be difficult to forecast, the precipitation type organization with the "A" storms usually involves a sharp transition from rain south/east to snow north/west due to fairly deep cold air funneled in from the north on the west side of the surface low, while the "B" storms, like this year's, have a more pronounced component of warm air flowing in over top of colder air, due to the initial surface and lower atmosphere circulation located to our west. That can lead to broad transition zones, and even pockets of varied precipitation type, that add substantial areas of sleet and freezing rain to the mix, as we saw with this year's storm. By the time this year's storm had more completely transitioned to a single intense surface low, it's main effects had moved a little north of us and it proceeded to drop very heavy snow on a swath from northern VA to southeastern NY, before pulling away into the Atlantic well southeast of MA. The 2000 storm, with a more negatively tilted upper-level trough/low, meaning the southern part of the trough was farther east than the northern sections, saw the surface low hug the Atlantic seaboard more tightly, with the surface low tracking along the coast of Maine.
Jan. 31, 2016 | Tags: general meteorology, past weather, winter weather

Question: Was there a 57 inch snowfall on top of Mt Mitchell with this latest snowstorm? — Clarence Caldwell

Answer: You're asking about the storm of January 21-22, and the short answer is we don't quite know yet, but it seems quite doubtful. An initial report from the site went on a list of reported snow totals posted by the Greenville-Spartanburg NWS office, showing all other western NC totals as ranging between about 8 and 18 inches, with the one value at Mt Mitchell listed as 57 inches. This includes 41 inches on Saturday the 22nd, which would shatter the previous one-day record for NC, also from Mt Mitchell, of 36 inches on March 13, 1993. The State Climate Office of NC, together with the NWS, will be investigating this report to determine if the numbers are valid, or if there may have been problems associated with high wind and heavy drifting, to see if these values should be accepted and a new record established.
Jan. 30, 2016 | Tags: controversy, records/extremes, snow

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