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Answer: If you click the "Hurricanes" link at the upper right hand portion of our main weather page, and then scroll down the right hand side of that page, you'll find a "printable tracking map" image that will take you to a pdf format tracking map covering the Atlantic basin. The map includes a list of all the storm names for the 2009 season.
Sep. 5, 2009 | Tags: hurricanes, maps & codes

Answer: Lightning can travel between charge centers in separate clouds (cloud-to-cloud, CC), those within a single cloud (in-cloud, IC) and between the cloud and surface (cloud-to-ground, CG). There tend to be many more IC and CC flashes than CG strikes, though the ratio can be highly variable. On average, there are about three IC or CC flashes for every one that strikes the ground. CG flahes are generally more dangerous and destructive, as they may strike people, cause fires, interrupt power or damage electrical devices, while flashes aloft only rarely cause problems, for example by striking aircraft. However, any storm producing flashes aloft should be assumed capable of also producing some ground strikes.
Sep. 4, 2009 | Tags: lightning, thunderstorms

Answer: A tropical wave is characterized by an elongated trough of low pressure, with winds flowing through it in a curved manner (counterclockwise and usually toward the west in the Atlantic basin) but not in a closed circulation. When the system develops a low pressure center and a closed circular flow, it is then a cyclone that is called a tropical depression if sustained wind speeds are below 39 mph, and called a tropical storm when the winds reach that threshold.
Sep. 3, 2009 | Tags: hurricanes, winds

Answer: When two tropical cyclones close within about 900 miles, they sometimes exhibit something called the Fujiwhara effect, which involves the two systems beginning to "dance" around one another, effectively orbiting a common centerpoint. Rarely, a stronger storm may also disrupt the organization of a weaker one, with the less intense system eventually absorbed into the circulation of the other.
Sep. 2, 2009 | Tags: hurricanes

Answer: If your question is "why wasn't it a dark cloud?" then the answer is it is all a matter of perspective and lighting. Even the darkest of storm clouds as seen from underneath or with the sun behind the cloud, will appear white if it is lit by the sun on the side facing you. If the sun is very low or has just set, it may also appear light in color by contrast if there are more distant clouds behind it that are not being lit as brightly and thus appear darker. In either case, if the cloud has the proper characteristics of moisture, height, temperature distribution, and vertical motions, it can produce in-cloud, cloud-to-cloud or cloud-to-ground lightning that may be visible.
Sep. 1, 2009 | Tags: clouds, lightning

Answer: There doesn't appear to have ever been a hurricane Kathy in the Atlantic basin since the practice of using human names for the storms began in 1953. Since 1979, when male names were added to the mix as well, the only female names starting with "K" in the Atlantic have been Katrina (now retired due to the deadly 2005 storm), Kate, Katia and Karen. Those last three names will be reused every six years unless one of them also warrants retirement. Kathy also does not show up on the list of names for other basins around the world at this time. All current tropical cyclone name lists are available at www.nhc.noaa.gov/aboutnames.shtml.
Aug. 31, 2009 | Tags: cool sites, hurricanes

Answer: No. The tires on automobiles do not act as effective insulators in this case. However, the metal skin and frame of many cars can act to diffuse and direct current from a strike around the outside of the vehicle, protecting those inside. As a result, lightning safety experts consider most hard-top, fully enclosed cars, trucks and buses to be relatively safe locations, with the caveat that it is best if you avoid touching any metal objects that have a conducting pathway to the outside. Open-top or soft-top vehicles are not considered good protection, and there are question marks regarding cars with non-metallic exteriors like plastic or fiberglass.
Aug. 30, 2009 | Tags: lightning, weather & health

Answer: As you noted, the customary "official" reference for named storms with sustained winds of 74 mph and up in the Atlantic and eastern Pacific basins is "hurricane," while in some other basins they are referred to as typhoons, tropical cyclones, severe tropical cyclones, or severe cyclonic storms, all followed by the name assigned to that specific storm. However, in a more generic sense, a cyclone is any closed low pressure circulation that exhibits counterclockwise rotation in the northern hemisphere and vice versa in the south. The reference by NWS in the map you saw, then, was to the fact that an open tropical wave was intensifying and developing into a closed circulation. By this generic reference, all tropical depressions, tropical storms, hurricanes, typhoons, and the rest are "tropical cyclones."
Aug. 29, 2009 | Tags: hurricanes

Answer: Tornadoes certainly do occur in both those areas, but geographic factors lead to a much lower prevalence there than in parts of the United States. For example, a French study of significant (F2 and stronger) tornadoes there identified 58 between 1960 and 1988, and established that the frequency of such tornadoes was about 1/15th that of the U.S. Great Plains region. Notable tornadoes have been reported in most other European countries as well. It's likely we don't hear about more of them because they are both infrequent and often deemed of primarily local rather than international news value.
Aug. 28, 2009 | Tags: tornadoes

Answer: Clouds that are deep enough to produce heavy rain, lightning and hail contain a tremendous amount of water in the form of cloud droplets, rain drops, ice crystals and hail, all of which can scatter, reflect and absorb light. If you happen to be on the opposite side of such a cloud from the sun, it will appear dark due to the lack of light passing though it, and likewise it will become rather dark underneath the storm. On the other had, if you see the same storm cloud, but you are between the sun and the cloud, it will appear bright white due to the light it reflects and scatters back toward you.
Aug. 27, 2009 | Tags: atmospheric optics, clouds, thunderstorms