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Recent Questions

Question: It could just be that there a lot of cool people in Sanford... — Bob H

Answer: For anyone who hasn't been reading recent AskGreg posts, Bob is referring to a recent question from Alex Webb regarding the common morning chill reported there relative to many other nearby locations. You can see that response by using the search tool at the top of the AskGreg page and searching for Alex's name, or the word "Sanford." Bob, we suspect it's a different kind of cool you're talking about! Also of note is the fact that while, for example, the morning low temperature in Sanford averages more than two degrees F colder than at RDU during the winter months, there is typically a larger "diurnal" (daily) range at Sanford, and the high temperature there averages a little under two degrees F warmer than RDU through that same period.
Apr. 3, 2017 | Tags: instruments, normals

Question: How long does the heavy tree pollen in the Fayetteville area tend to last? Any idea when we should expect it to subside? — Jeff Christensen

Answer: We don't have a confident means of predicting exactly when the pine pollen (main producer of the really big yellow-green powder) releases will cease. The pine pollen peak can vary some year to year, but it usually is most noticeable for about 2-4 weeks, typically beginning as early as mid-March and ending as late as early May. Given that many spring indicators responded to the warm January and February temperatures this year around 2-3 weeks early or so, it seems reasonable to think there's at least a chance at pine pollen tapering off a little on the early side this year, perhaps by a week or two into April, although the stretch of cold weather we experienced a little ways into March does seem to have produced two periods of increased pollen production with a lull in between, so the overall span from earliest pine pollen to the last could very well be longer this year than that usual 2-4 weeks we mentioned.

We do make links to some pertinent information available here on our web site. Just click on the "resources" link near the top of the main weather page, and scroll down to select the second page of the resources list. There you'll find links labeled "Daily Pollen Count Forecasts," which takes you to a map where you can click your way to a 5-day forecast of allergen levels and types for a number of cities across NC, and "NC Division of Air Quality Pollen Count," where you can see a graph of recent pollen counts taken in Raleigh (we suspect Fayetteville would be similar, perhaps running a few days ahead of Raleigh due to the average temperatures there being a few degrees warmer). Near the top of that graph is also a link to see the latest available tabular report, which includes a listing of what the top observed pollen species are, and also includes a link to a calendar where you can retrieve previous written reports for any date during the season.
Apr. 2, 2017 | Tags: pollen,

Question: I saw a firefly in the woods next to my house in Raleigh on March 26th. It seemed remarkably early to me. From a weather perspective, is this a normal time for fireflies to be active? — Nick Mullins

Answer: As with many aspects of "spring," from a phenological perspective, things have been running ahead of schedule this year due to the unusually and persistently warm weather we experienced through a good part of January and most of February. In terms of leaf and plant development, we ran about 2-3 weeks ahead of usual, and that may have been reflected in the early appearance of fireflies that you noted as well. We checked reports from the past ten years or so on firefly sightings around the southeastern U.S. and found that most of those years the first reports in central NC occurred generally 1-3 weeks into April. However, this year and in 2012 (which also featured a very "early spring" for much of the country), they were seen around here by the 2nd-3rd week of March.
Apr. 1, 2017 | Tags: normals, weather & health

Question: I was wondering on the "drought" we are seeing if it is really somewhat misleading. I know we are down for the year in rainfall since January 1, but we had a mega surplus of rain thanks to Mathew from last October.... so are we really that dry? — David Jones

Answer: The most recent U.S. Drought Monitor and NC Drought Management Advisory Council information at the time we answered your question indicated abnormally dry, but not drought, conditions from around Raleigh south and southwest, while areas northwest of Raleigh were designated as moderate drought. You make a good point about the large amounts of rain from last fall, and in fact that is thus far translating into near-normal water supplies in major reservoirs. On the other hand, lower than normal rainfall over the past few months has led to stream flow readings over much of central and western NC that are in many cases in the lowest 10th percentile of historical observations. Given this, soil moisture may trend down from current mostly adequate to slightly dry levels, and the drought designation would appear to be based on these "short-term" dry conditions and potential impacts (mainly to soil and agriculture), while the western third or so of the state is considered to be in long-term drought that is severe to extreme for the southern mountains and southern foothills. This implies impacts not just on agriculture and soils, but hydrologic and ecologic impacts (water supplies, power production, effects on wildlife, etc) as well.
Mar. 31, 2017 | Tags: drought, rain

Question: It seems to me that the past few months have had more days with noticeable wind than what is normal. Is this true? — Rick

Answer: We could not confirm that based on observed winds compared to normals at the RDU airport, although because of the way long-term records are kept it can be difficult to compare the number of days in a given month with winds that would seem especially high to the normal number of those days. What we were able to do is check the mean wind speeds for December, January and February and compare those to historical averages. It turned out that each of those three months has mean wind speeds this year that were lower than average (5.2 mph in December, compared to 6.2; 6.6 mph in January, compared to 6.9); and 6.3 mph in February, compared to 7.3). We suspect that since the lowest mean speed of the year for our area occur during the fall months, the increase in wind speeds that is typical of winter into early spring creates the perception that it is unusually windy.
Mar. 30, 2017 | Tags: normals, winds

Question: It's World Meteorological Day, and it's being officially recognized with a new cloud named Asperitas. Is this a new type of cloud because of climate change? — Dunrovin

Answer: Asperitas is one of a number of new designations for describing certain cloud types and sub-types. This all comes as the World Meteorological Organization issued the first update to its International Cloud Atlas since 1987 on World Meteorological Day. The 2017 update adds a number of new designations, although the clouds themselves are not new, or a result of climate change. The "asperitas" label is now applied as a subtype (known as a "supplementary feature" in the cloud atlas), for example, stratocumulus asperitas or altocumulus asperitas. This type of cloud formation, which can have a very dramatic appearance under the right circumstances, was proposed as a new type called "undulatus asperatus" a number of years ago, with that description giving way to the new feature designation in the updated atlas. The only new cloud species in the updated atlas is "volutus," which is now an official name for the phenomenon that's been commonly referred to as a "roll cloud." There are a number of other new designations, and they are highlighted at, where you can also make your way back to the main site for the new cloud atlas. We've published a couple of blog posts about these types of clouds here on our site in the past. You can see those posts at, which discusses the initial effort to apply a new name to the clouds, and, in which we discuss the physical reasoning behind their appearance in response to photos sent in by a local viewer.
Mar. 29, 2017 | Tags: clouds, cool sites

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: I have noticed that Sanford is usually cooler than surrounding areas in the morning. Any ideas why? Seems pretty consistent. — Alex Webb

Answer: The temperature for Sanford that is included on our weather maps on TV and the temperature maps and current condition page here on our web site comes from the weather station located at the Sanford-Lee County Regional airport and is maintained by the NC DOT Aviation Division following FAA guidelines. The airport there is in an area that features fairly sandy soil favorable for strong cooling at night and heating by day, and is topographically located with somewhat higher terrain just to the northeast, northwest and southeast, which can result in pooling of denser, cooled air, especially on nights with light winds and relatively clear skies. On early mornings with light winds and low humidity, temperatures may fall more precipitously there than some other airport locations, although there are times the Erwin and Southern Pines airports are similarly cool. Daytime temperatures often more closely match nearby locations, and overnight values come closer to doing so as well when cloudy and breezy conditions prevail.
Mar. 27, 2017 | Tags: cold, general meteorology, instruments, maps & codes

Question: I live in Clayton, and I would like to build a run in shed for the horses. Which way should I face the opening so that the prevailing winds don't blow in? — Liz

Answer: There can be some very localized terrain influences on wind directions such that your prevailing winds could differ a bit from those on the broader scale across the region, but most weather reporting sites around the area, which use "surface" wind measurements that are taken about 10 meters above ground level, consistently show our prevailing direction to be southwesterly for most of the year, with the exceptions being September and October, when the prevailing direction reverses to northeasterly. There are also some fairly common occurrences of gusty, cold winds from the northwest during the winter in the wake of passing cold fronts or departing coastal low pressure systems. If all that holds reasonably well for your property, you might be well-served to face the opening toward the southeast.
Mar. 26, 2017 | Tags: normals, weather & health, winds

Question: Greg, you are slipping. LOL, the chart you showed at 6 comparing cold to 1960 was "March Madness!" Keep up the good work. — Gene W Berg

Answer: A missed opportunity, indeed, but as you mentioned, the real madness was how cold March of 1960 was (or maybe, having all but one ACC team out of the tournament after the first weekend this year)! We've taken a chillier turn this March in the wake of a record warm February, but we're not even remotely as cold as that year. For reference, the "normal" average temperature for March at RDU is 51.1 degrees. Through the first three weeks of this March, we've averaged about 46.8 degrees, and will probably finish the month with an average a little warmer than that. March 1960, though, ended with an average temperature of 37.6 degrees. This was a full 4.4 degrees colder than the second coldest March since 1887, which was 1947 with 42.0 degrees. The third coldest March was in 1915, with 42.7 degrees. Not coincidentally, perhaps, 1915 was also notable for the 10-inch snow that occurred in Raleigh on April 3rd. Also of interest is that the very cold March of 1960 featured observed snowfall in Raleigh on the first three Wednesdays of the month!
Mar. 25, 2017 | Tags: cold, past weather, records/extremes

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