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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: Most outlooks for the 2013 Atlantic season indicate a tendency toward above-normal activity. As examples, the forecast from Colorado State University is for 18 named storms, 9 hurricanes and 4 major hurricanes (meaning those reaching category 3 or higher intensity). As a comparison, for the thirty-year period 1981-2010 (used for most climate "normal" calculations) the median observed numbers were 12, 6.5 and 2, respectively. They also indicate the probability of an east coast landfall at 48%, which is above the long term average of 31%.

A local research group at NC State University makes their forecasts in the form of likely ranges, and they are expecting 13-17 named storms, 7-10 hurricanes and 3-6 major hurricanes, generally in good agreement with the group from CSU. The National Oceanographic and Atmospheric Administration's Climate Prediction Center will issue its 2013 projections later in May.
May. 3, 2013 | Tags: hurricanes, preparedness

Answer: You might like to try out a very nice site hosted by NOAA's National Ocean Service. It is an interactive tropical cyclone track database and mapping system. Regarding your question, for example, I was able to simply type "Tortola, British Virgin Islands" into the location box and click GO, which zooms directly to that location, and displays a default 65 nautical mile radius with every cyclone track from the years 1842-2011. This initially looks like a great number of storms, but you can then apply a filter to search for certain time frames or certain groups of years. In your case, I applied a filter to check for July storms from the entire range of years. The result showed that in during that 169-year span, one tropical storm and four hurricanes passed within that distance of Tortola in July. This equates to about a three percent chance, or a nearby storm in July once every 33 years or so. The site address is csc.noaa.gov/hurricanes/# and there is another place you can go to get month-by-month maps of similar probability contours for the Atlantic basin. It is an answer to a frequently asked question at NOAA's Hurricane Research Division web site, located at www.aoml.noaa.gov/hrd/tcfaq/G12.html.
May. 1, 2013 | Tags: cool sites, hurricanes, past weather

Answer: The only weather-related names that we are aware of that are subject to official rules and managed by government agencies charged with weather forecast and warning responsibilities are those for tropical cyclones. Of course, Sandy is an example of such a storm and the name was applied to that storm by the National Hurricane Center, taken from a list of Atlantic Basin names that is compiled and managed by a subcommittee of the World Meteorological Organization. The list includes includes six years worth of names at any time, and those names are re-used every six years unless a storm produces a level of destruction and/or loss of life that would make such re-use insensitive to those who suffered the consequences. In that case, the name is retired from the list and another name starting with the same letter and having the same gender is chosen to take its place. We can be certain that Sandy will be retired from that list and never used again as the name for a tropical cyclone in the Atlantic basin.

The same kind of rules do not necessarily apply to unofficial or informal names that arise by way of social media, journalism, private businesses or popular use.

Apr. 9, 2013 | Tags: Floyd, hurricanes, maps & codes

Answer: There is a lag in the number of Atlantic tropical cyclones such that the peak activity on average occurs from late August to early October or so rather than at the time of the strongest incoming solar radiation of the year (in late June). This is partially related to a similar lag in the maximum sea surface temperature (on average), as well as to some other favorable factors for supporting development of tropical cyclones that also tend to peak in that time frame. These include the frequency and intensity of low pressure disturbances called easterly waves moving out of west Africa and across the tropical Atlantic, and a yearly minimum of vertical wind shear that tends to occur in the tropics through this time frame. The reduced vertical shear allows storms to develop and maintain organization more efficiently, whereas greater amounts of such shear tends to disrupt or weaken, and in some cases prevent altogether, the development of named storms.
Mar. 30, 2013 | Tags: hurricanes

Answer: You're right that the moist, high-wind-shear area in the right front quadrant of a land-falling hurricane often (not always) triggers a swarm of short-lived and usually rather weak tornadoes. It would be overstating things to say a hurricane can never set off a violent EF5 tornado, but the environment around hurricanes is generally characterized by deep moisture and warm air aloft that limits the kind of extreme instability and explosive updrafts that are usually associated with the most intense tornadoes. This is reflected somewhat in the fact that most hurricanes, in spite of being huge convectively-driven storms systems, produce relatively little lightning.
Mar. 4, 2013 | Tags: hurricanes, tornadoes

Answer: While the term superstorm became widely used by journalists, politicians and some others, most meteorologists refer to the storm as either Hurricane Sandy (during the time when it had tropical characteristics and sustained winds 74 mph or higher) or Post-Tropical Storm Sandy (covering the period when it had transitioned to a more extratropical structure). There is no definition that we're aware of for a superstorm, so that should probably be considered an informal/unofficial term that refers to an especially, large, intense or destructive storm.
Jan. 19, 2013 | Tags: controversy, hurricanes

Answer: Sandy did have a very low central pressure, but due to the difficulty in relating central pressure to wind speed, storm surge and overall damage potential in hurricanes (due to a poor correlation between them and many exceptions to any generalized rules), there actually is no such thing anymore as a "Category 4" pressure. Due to the issues mentioned, pressure (and storm surge) were removed from the Saffir-Simpson Hurricane Intensity Scale, and it was renamed the Saffir-Simpson Hurricane Wind Scale, beginning operationally with the 2010 season.

Sandy was a good example of a storm that only reached Category Two and then made landfall as a post-tropical storm with Category One equivalent winds, but it's large size, the long duration of strong winds, it's direction and speed of motion, and the shape of the shoreline where it struck all yielded high storm surges and the accompanying damage. There is a lot of work underway in post-storm assessments to address whether any changes are needed in the way warnings and advisories are communicated, and how, if possible, the process can be improved.
Dec. 19, 2012 | Tags: flooding, hurricanes, weather & health, winds

Answer: So far, one has not been recorded for historical purposes, though we can't say with certainty that it has never happened. The vast majority of the time, tropical cyclones develop at latitudes 5 degrees or more away from the equator due to the requirement for a stronger Coriolis force (which arises from the rotation of the earth and is strongest near the poles and zero at the equator) to organize the rotating flow of winds toward the center (counterclockwise in the northern hemisphere and vice versa). In addition to assisting the development of these cyclones, the gradient of the Coriolis force tends to cause them to drift toward the poles in the absence of notable steering winds, which tend to be quite light near the equator. This probably plays a role in the lack of observed storms crossing over. If a well-developed tropical cyclone did somehow get steered across the equator, the changes in Coriolis force would oppose the direction of its winds, but would probably not be a strong enough effect compared to other factors (like conservation of angular momentum) to disrupt the storm. You can see a map with the known tracks of most past storms at en.wikipedia.org/wiki/File:Global_tropical_cyclone_tracks-edit2.jpg, where you'll see the absence of paths moving across the equator.
Dec. 8, 2012 | Tags: cool sites, general meteorology, hurricanes, maps & codes

Answer: Classically organized tropical storms and hurricanes do indeed draw their primary energy from warm ocean water below, together with the moisture that transfers from the ocean surface into the storm. However, when these storms move far enough north and begin interacting with other mid-latitude weather features, as Sandy did once it reached about the latitude of Florida, the picture becomes more complex, as the storm can become a hybrid, with part-tropical and part-extratropical characteristics and energy sources. As Sandy swung around the NC coast and then started driving in toward the mid-Atlantic coast, it continued to transition toward a more extra-tropical organization that allowed it to intensify based on horizontal temperature contrasts and upper-level divergence associated with a deep upper level trough it was interacting with. These processes would be referred to by meteorologists as "baroclinic" in nature, and this was referred to a number of times in National Hurricane Center discussions (well before it happened) as a likely reason for intensification despite increased wind shear and cooling water temperatures.
Nov. 14, 2012 | Tags: general meteorology, hurricanes

Answer: We can't speak directly to the decision-making on the part of other media sources, but would speculate that it is a means of combining the fact that Sandy was a high-impact storm that was hurricane first, a hybrid storm as it made landfall and a lingering extratropical storm after landfall that also had high impacts in the form of wintry weather in parts of the Appalachians. At WRAL, we chose to refer to the storm as Hurricane Sandy, unless specifically referring to its effects after landfall, when it would be referred to as Post-tropical Storm Sandy, or simply "Sandy."
Nov. 10, 2012 | Tags: hurricanes, wral.com