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Question: Can I get the Weather sent to my email? — Cathy Bromiley

Answer: Yes, to do so click on the "e-mail alerts" link near the very bottom of most pages on our site, and it will take you to a management page where you can select from a variety of weather and news feeds to be delivered to your e-mail address. Note that you do need to be a registered user of WRAL.com, and logging into your account provides you with the access needed to select and deselect your desired e-mail alerts.
Nov. 15, 2009 | Tags: wral.com

Question: The average barometric pressure at mean sea-level (MSL) is? — Kata

Answer: Standard sea level pressure can be expressed in a number of different ways. For example, 14.7 pounds per square inch, 760 mm Hg, 29.92 inches Hg, 1013.25 millibars, 101.325 kiloPascals, 1 atmosphere and so on. Since they all represent the same pressure, you can use those values to convert between units.
Nov. 14, 2009 | Tags: general meteorology, normals

Question: Did anyone report a meteor or fireball around 8:30 Friday night Nov 6 2009? While looking east from Surf City NC, I saw a strange bluish light moving vertically "downward." It appeared to have the width of a half moon and it appeared to flutter or oscillate side to side as it moved. I thought it might have been a relatively close (half a mile?) falling deflated weather balloon illuminated for some reason from below (why I don't know) but my sister-in-law saw the same event from about 50 miles inland. It was visible for maybe 0.5 to 1.5 seconds, about the same time as a meteor. — Steve

Answer: Unfortunately a fireball sighting log hosted by the American Meteor Society has not been updated since late October due to problems with the reporting form. Based on the time of year of your reports, and the overall description, it sounds as if you and your sister witnessed a fireball (very bright meteor), quite possibly associated with the Taurid meteor shower. On the following evening, a Taurid fireball was widely seen in California, and some photos and videos were captured, which you can peruse in the "Weekend Fireballs" section at http://www.spaceweather.com/archive.php?view=1&day=09&month=11&year=2009.
Nov. 13, 2009 | Tags: astronomy, cool sites

Question: You say that we are on course for one of the driest years on record. But it seems to have rained often. How does 2009 compare for number of days with measurable rain? — Paul MacDougal

Answer: As you imply with your question, it is certainly possible to have below normal rainfall while receiving rain in trace or rather small measurable amounts fairly often. This year has fit into that category to some extent. Through the end of October, we had six months with above normal number of days with at least one hundredth of an inch of rain, while four months were below normal. In total during that time, 104 days brought measurable rain, when the normal for the first ten months of the year is 95.
Nov. 12, 2009 | Tags: normals, rain

Question: How hot does air have to be to evaporate water? How cold does air have to be for it to be condensed? — Ashley

Answer: The answer all depends on how much water vapor is in the air already, as indicated by the dew point. Water can evaporate as long as the temperature of the air above it or surrounding it (in the case of suspended drops) has a dew point lower than the temperature of the water. If the water and air are at the same temperature, then as long as the temperature is higher than the dew point, water can evaporate. On the other hand, water vapor will condense into liquid water if the temperature of the air containing the water vapor is cooled to the dew point or below, or can condense onto an adjacent surface if that surface is cooled to the dew point or below.
Nov. 11, 2009 | Tags: general meteorology, humidity/dew point

Question: Why is is that last night I could see the State Fair fireworks from my house as usual, but for the first time in history I could not hear them at all? What atmospheric condition caused me not to be able to hear them? — Sheila Alston

Answer: Sound waves traveling horizontally through the atmosphere can be and usually are refracted, or bent, upward or downward depending on the vertical profiles of temperature (and the associated variations in density) and wind. Depending on the shape of the temperature profile and the origin point of the sound, it can be a simple matter of bending the sound upward and away from the surface so that sound can't be heard very far from the origin, or a simple matter of bending downward at a curvature close to that of the earth's surface so the sound can be heard very far away. There can also be more complex scenarios that create concentric shadow and amplification zones in which you might, for example, find yourself in a location where no sound is heard, while someone a mile closer to the source and someone a mile farther away hears it more loudly than usual. Conditions appeared to be conducive for a temperature inversion to form on the night you mentioned, but we would have to have detailed vertical profiles above the fairgrounds to work out any of the specifics of how the sound may have been distributed.
Nov. 10, 2009 | Tags: general meteorology

Question: On the central NC radar, can you indicate the approximate direction that a front or weather system is moving? I frequently check the web site and central radar for planning but the image is still and I can't see if the front is moving towards Rocky Mount or going north toward Virginia, etc. — Billy

Answer: The central NC radar image, along with the other more zoomed-in views, can be looped by clicking the 1-hour or 8-hour loop links. This will provide a visual indication of the direction and speed of movement of precipitation echoes, as well as some sense of whether they are intensifying or weakening. You can also lapse images from Dual Doppler 5000 or a composite of National Weather Service radars on a scalable map background by using the iControl radar feature.
Nov. 9, 2009 | Tags: weather radar

Question: About 7:10 PM om Friday October 23, 2009 in Pinehurst I was out walking, and in the east-southeast sky was a large yellow light slowly descending. As is came towards the horizon there was a distinctive tail. Would it have been a meteor, comet, or space junk? — Anonymous

Answer: Your description pretty firmly rules out a comet, as they are distant objects that do not appear to move immediately across the sky at a rate any different than stars, planets and so forth. While a piece of re-entering space debris can't absolutely be ruled out, it seems much more likely you saw a meteor. On that date, three different meteor showers are active, although not at their peaks, and of course a "sporadic" meteor not associated with a particular shower is always possible as well. It is interesting that you noted fairly slow movement and a yellow color. That description is quite consistent with meteors produced as part of the Southern Taurids shower. You can read about that and other showers throughout the year at www.namnmeteors.org/appendixA.html.
Nov. 8, 2009 | Tags: astronomy, cool sites

Question: Was there ever snowfall on record for the month of October here in Raleigh NC? — Keith Myatt

Answer: Climate records from the Raleigh-Durham airport do not show any snowfall in October, with the earliest trace of snow there reported on November 2nd, 1954, while the earliest measurable snow there was on November 6th, 1953, when .6" was recorded. A different station in Raleigh with a much longer period of record did record a trace of snow as early as October 24th, back in 1910.
Nov. 7, 2009 | Tags: past weather, records/extremes, snow

Question: I read your answer from March 8, 2009 to "what is it called when fog freezes," but am still a little confused. When the air temperature is below freezing, why doesn't fog freeze into a solid mass in mid-air? — Wayne Smith

Answer: Since fog is composed of tiny droplets, or in the case of ice fog tiny frozen crystals, separated by significant amounts of air, it could not and does not form a solid mass in the air, even when the particles themselves are frozen. The point regarding the air being less than freezing, though, is that water needs an appropriate surface upon which to initiate freezing at 32 degrees F, and droplets suspended in air will not typically freeze at that temperature unless they encounter something called an ice nucleus. Even then, with small droplets the ice nuclei are usually most effective at causing the droplets to solidify at temperatures below about 14 degrees F.
Nov. 6, 2009 | Tags: clouds, cold, visibility/fog/dust

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