N aschi-
The Arabic name for a northeasterly wind that ocurrs in winter on the Iranian coast of the Persian Gulf, especially near the entrance to the gulf and also on the Makran coast.
Narbonnais-
(Also spelled narbone.) In France, a wind coming from Narbonne; a north wind in the Roussillon region of southern France resembling the tramontana. If associated with an influx of arctic air, it may be very stormy with heavy falls of rain or snow. It is especially violent in the region of Perpignan where it blows in a succession of squalls for several days. In Provence it is rarer and blows from the west. In lower Languedoc and the southern Cévennes, the narbonnais is an infrequent, mild, moist, moderate southwest wind in winter and early spring, sometimes bringing thunderstorms.
Near gale-
Wind with a speed between 28 and 33 knots or force 7 on the Beaufort wind scale.
Night wind-
Dry squalls that occur at night in southwest Africa and the Congo. It is likely that this term is loosely applied to other diurnal local winds such as mountain wind, land breeze, midnight wind, etc.
Nimbostratus-
A principal cloud type (cloud genus), gray colored and often dark, rendered diffuse by more or less continuously falling rain, snow, sleet, etc., of the ordinary varieties and not accompanied by lightning, thunder, or hail.
Noctilucent clouds-
(Rarely called luminous clouds.) Thin silvery blue cirrus like clouds frequently seen during summer twilight conditions at high latitudes (above 50 degree) in both hemispheres. They are the highest visible clouds in the atmosphere, occurring in the upper mesosphere at heights of about 85 km, and are closely related to the polar mesospheric clouds seen in satellite observations at similar altitudes over the summer polar cap. Noctilucent clouds are now known to consist of tiny ice particles with dimensions of the order of tens of nanometers, growing in the extreme cold of the summer polar mesopause region. The condensation nuclei on which the particles grow are thought to be either smoke and dust particles of meteoric origin or large hydrated positive ions. Strong upwelling of air from below, associated with a pole to pole meridional circulation in the upper mesosphere, is responsible for both the extreme cold and the upward flux of water vapor. Although water vapor mixing ratios are very low (less than 10 parts per million by volume) in the region, the temperatures are also low enough to produce a high degree of supersaturation at times. Anomalously strong radar echoes from the region, known as polar summer mesospheric echoes, are also associated with the clouds. Compare nacreous clouds, polar stratospheric clouds.
Nocturnal boundary layer-
The cool layer of air adjacent to the ground that forms at night. At night under clear skies, radiation to space cools the land surface, which in turn cools the adjacent air through processes of molecular conduction, turbulence, and radiative transfer. This causes a stable boundary layer to form and grow to depths of a few hundreds of meters, depending on the season. Many interacting processes can occur within the statically stable nocturnal boundary layer: patchy sporadic turbulence, internal gravity waves, drainage flows, inertial oscillations, and nocturnal jets.
Nocturnal cooling-
The lowering of temperature during nighttime, due to a net loss of radiant energy.
Nonsupercell tornado-
A tornado that occurs with a parent cloud in its growth stage and with its vorticity originating in the boundary layer. The parent cloud does not contain a preexisting midlevel mesocyclone. Landspouts and gustnadoes are examples of the nonsupercell tornado.
Nortada-
A strong, persistent northerly wind in the Philippines.
Norte-
The winter north wind in Spain. 2. A strong cold northeasterly wind in Mexico and on the shores of the Gulf of Mexico. It results from an outbreak of cold air from the north; actually, the Mexican extension of a norther. See chocolatero. 3. A norther in Central America.
North foehn-
A northerly foehn wind blowing down the Italian side of the Alps. The northern slopes are normally cooler than the southern slopes, and the dynamic warming is often insufficient to overcome the difference of temperature. Hence a warm dry northerly wind of foehnlike character occurs less frequently than the south foehn.
Northeast storm-
A cyclonic storm off the east coast of North America, so called because the winds over the coastal area are from the northeast.
Northeaster-
A northeast wind, particularly a strong wind or gale.
Norther-
A northerly wind; in general, a cold windstorm from the north.
Northwester-
(Often contracted norwester.) A northwesterly wind (as Canterbury northwester).
