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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 DEF

A... radar precipitation echo which appears as a hook in the southwest sector of a thunderstorm.  2, record 1, English, - tornado%20echo

Record number: 1, Textual support number: 1 CONT

... the development, growth and movement of a tornado echo and its associated thunderstorm echo were observed on the plan-position indicator (PPI) of [a radar] as the storm crossed east-central Illinois into Indiana. ... Included in this report are: ... a large number of selected radar photographs depicting the history of the tornado echo and its associated thunderstorm echo ...  3, record 1, English, - tornado%20echo

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 DEF

[...] écho radar de la précipitation en forme de crochet qui apparaît dans le secteur sud-ouest de l'orage.  1, record 1, French, - %C3%A9cho%20de%20tornade

Record 1,  Textual support,  Spanish

Record number: 1, Textual support number: 1 DEF

[...] eco radar de la precipitación que aparece como un gancho en el sector sudoeste de una tormenta.  1, record 1, Spanish, - eco%20de%20tornado

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 DEF

A thunderstorm with negligible precipitation reaching the ground.  2, record 2, English, - dry%20lightning%20storm

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 DEF

Orage électrique s'accompagnant d'une précipitation négligeable.  3, record 2, French, - orage%20%C3%A9lectrique%20sec

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 DEF

... the rotating, localized lowering of the cloud base beneath the rain-free portion of a thunderstorm that often precedes tornado development ...  2, record 3, English, - wall%20cloud

Record number: 3, Textual support number: 1 CONT

Wall clouds can range from a fraction of a mile up to nearly five miles in diameter, and normally are found on the south or southwest(inflow) side of the thunderstorm. Even though this cloud is lowering, it remains attached to the rain free cloud base of the thunderstorm. It is usually located south or southwest of the visible precipitation area, and marks the strongest updraft in the thunderstorm. The wall cloud develops as the strong updraft draws in surface moisture from several miles away.  3, record 3, English, - wall%20cloud

Record number: 3, Textual support number: 1 OBS

"Wall cloud" also is used occasionally in tropical meteorology to describe the inner cloud wall surrounding the eye of a tropical cyclone, but the proper term for this feature is "eyewall."  3, record 3, English, - wall%20cloud

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 CONT

Le précurseur typique de la tornade est le mur de nuages. C'est une partie de la base du nuage qui semble s'abaisser vers le sol. On le trouve normalement sur le flanc arrière droit de l'orage. Autrement dit, si l'orage arrive de l'ouest, il faut regarder vers sa partie sud-ouest. Le mur de nuages se forme dans la zone sans précipitations et montre généralement un mouvement de rotation, sous la base du nuage.  3, record 3, French, - mur%20de%20nuages

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 CONT

Winter thunderstorms, also known as "thundersnow, "are a somewhat rare type of thunderstorm during which snow, rather than rain, falls as the primary form of precipitation.  3, record 4, English, - thundersnow

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 CONT

Un orage de neige, «thundersnow» en anglais, est un orage dont les précipitations tombent principalement sous forme de neige.  2, record 4, French, - orage%20de%20neige

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 DEF

A term ... that may be used in air-ground communication when meteorological information is being transmitted to aircraft.  1, record 5, English, - CAVOK

Record number: 5, Textual support number: 1 OBS

CAVOK refers to the simultaneous occurrence, at an airport, of the following meteorological conditions :(a) no cloud below 5000 ft, or below the highest minimum sector altitude(MSA), whichever is higher, and no cumulonimbus;(b) a visibility of 6 SM [statute miles] or more; and(c) no precipitation, thunderstorm, shallow fog or drifting snow.  1, record 5, English, - CAVOK

Record number: 5, Textual support number: 2 OBS

CAVOK: This term is pronounced "KAV-OH-KAY" and is derived from the words "ceiling and visibility OK."  2, record 5, English, - CAVOK

Record number: 5, Textual support number: 3 OBS

CAVOK: term standardized by the Glossary for Pilots and Air Traffic Services Personnel Committee.  2, record 5, English, - CAVOK

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 DEF

Terme [...] pouvant être utilisé dans les communications air-sol lors de la transmission de renseignements météorologiques aux aéronefs.  1, record 5, French, - CAVOK

Record number: 5, Textual support number: 1 OBS

CAVOK indique la présence simultanée, à un aéroport, des conditions météorologiques suivantes : a) aucun nuage au-dessous de 5000 [pieds] ou au-dessous de la plus haute altitude minimale de secteur (MSA), selon la plus élevée des deux, et aucun cumulonimbus; b) visibilité de 6 SM [milles terrestres] ou plus; c) absence de précipitation, d'orage électrique, de brouillard au sol ou de chasse-neige basse.  1, record 5, French, - CAVOK

Record number: 5, Textual support number: 2 OBS

CAVOK : Ce terme est prononcé «KAV-O-KÉ» et est dérivé de l'expression «ceiling and visibility OK» («plafond et visibilité OK»).  2, record 5, French, - CAVOK

Record number: 5, Textual support number: 3 OBS

CAVOK : terme normalisé par le Comité sur le Glossaire à l'intention des pilotes et du personnel des services de la circulation aérienne.  2, record 5, French, - CAVOK

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 DEF

A low-level, horizontal, wedge-shaped arcus cloud associated with a convective storm’s gust front (or occasionally a cold front).  2, record 6, English, - shelf%20cloud

Record number: 6, Textual support number: 1 CONT

Shelf Cloud... is usually attached to the thunderstorm base and forms along the gust front. The leading edge of the shelf is often smooth and at times layered or terraced. It is most often seen along the leading edge of an approaching line of thunderstorms, accompanied by gusty straight winds as it passes overhead and followed by precipitation. The underside is concave upward, turbulent, boiling, or wind-torn. Tornadoes rarely occur with the shelf cloud.  3, record 6, English, - shelf%20cloud

Record number: 6, Textual support number: 1 OBS

Roll clouds are ... completely detached from the convective storm’s cloud base, thus differentiating them from the more familiar shelf clouds.  2, record 6, English, - shelf%20cloud

Record number: 6, Textual support number: 2 OBS

Roll clouds and shelf clouds are both types of arcus clouds.  3, record 6, English, - shelf%20cloud

Record 6,  Textual support,  French

Record number: 6, Textual support number: 1 OBS

Les nuages en rouleau et étagère sont des types d'Arcus.  1, record 6, French, - nuage%20en%20%C3%A9tag%C3%A8re

Record 6,  Textual support,  Spanish

Record 7,  Textual support,  English

Record number: 7, Textual support number: 1 DEF

A supercell thunderstorm characterized by a relative lack of visible precipitation.  1, record 7, English, - low%2Dprecipitation%20storm

Record number: 7, Textual support number: 1 CONT

An LP supercell is characterized by a very long anvil, a small core region, a wall cloud at the back, and a thin precipitation curtain that usually lets some light through. Tornadoes can occur, but the main severe threat is usually large hail.  5, record 7, English, - low%2Dprecipitation%20storm

Record number: 7, Textual support number: 2 CONT

Visually similar to a classic supercell, except without the heavy precipitation core. LP storms often exhibit a striking visual appearance; the main tower often is bell-shaped, with a corkscrew appearance suggesting rotation. They are capable of producing tornadoes and very large hail. Radar identification often is difficult relative to other types of supercells, so visual reports are very important. LP storms almost always occur on or near the dry line, and thus are sometimes referred to as dry line storms.  1, record 7, English, - low%2Dprecipitation%20storm

Record number: 7, Textual support number: 3 CONT

LP supercells ... have little VISIBLE precipitation and most regions of the storm base are visible. The word VISIBLE is stressed here because these storms often contain very large hail which does not block light as much as rain as if issues from the cloud. LP storms usually have a striking visual appearance with corkscrew or "barber-pole" striations on the updraft tower. LP supercell tornadoes are often unobscured from viewing around the storm. Sometimes called LP’er.  3, record 7, English, - low%2Dprecipitation%20storm

Record 7,  Textual support,  French

Record number: 7, Textual support number: 1 CONT

L'orage supercellulaire à faibles précipitations comporte une enclume très allongée, un petit noyau, un mur de nuages à l'arrière et un mince rideau de précipitations qui laisse habituellement filtrer de la lumière. Il peut présenter un risque de tornade, mais il se contente habituellement de produire de gros grêlons.  1, record 7, French, - orage%20supercellulaire%20%C3%A0%20faibles%20pr%C3%A9cipitations

Record 7,  Textual support,  Spanish

Record 8,  Textual support,  English

Record number: 8, Textual support number: 1 DEF

A supercell thunderstorm in which heavy precipitation(often including hail) falls on the trailing side of the mesocyclone.  2, record 8, English, - high%2Dprecipitation%20storm

Record number: 8, Textual support number: 1 CONT

High precipitation supercells ... have a large precipitation core with heavy rains and possible hail. The rain can completely wrap an HP supercell tornado and obscure it from view on any side of the storm. Sometimes called HP’er.  5, record 8, English, - high%2Dprecipitation%20storm

Record number: 8, Textual support number: 1 OBS

Precipitation often totally envelops the region of rotation, making visual identification of any embedded tornadoes difficult and very dangerous. Unlike most classic supercells, the region of rotation in many HP storms develops in the front-flank region of the storm (i.e.,usually in the eastern portion). HP storms often produce extreme and prolonged downburst events, serious flash flooding, and very large damaging hail events.  2, record 8, English, - high%2Dprecipitation%20storm

Record 8,  Textual support,  French

Record number: 8, Textual support number: 1 CONT

Les orages supercellulaires à fortes précipitations sont observés le plus souvent dans le centre et le sud-est des États-Unis. On en voit à l'occasion en Ontario et au Québec, mais rarement dans l'ouest du Canada.  1, record 8, French, - orage%20supercellulaire%20%C3%A0%20fortes%20pr%C3%A9cipitations

Record number: 8, Textual support number: 2 CONT

Orage supercellulaire (HP-haute précipitation). Un orage supercellulaire est un orage qui a une très forte précipitation (pluie et grêle) et qui inclut aussi un mésocyclone. La forte précipitation enveloppe et cache le mésocyclone (et possiblement une tornade) ce qui fait son identification difficile. Les orages supercellulaires produisent aussi des vents descendants très forts. Les fortes précipitations peuvent causer des inondation soudaines et peuvent aussi produire de la très grosse grêle.  2, record 8, French, - orage%20supercellulaire%20%C3%A0%20fortes%20pr%C3%A9cipitations

Record number: 8, Textual support number: 3 CONT

orage supercellulaire à haute précipitation : l'on dit plutôt orage supercellulaire à fortes précipitations.  3, record 8, French, - orage%20supercellulaire%20%C3%A0%20fortes%20pr%C3%A9cipitations

Record 8,  Textual support,  Spanish

Record 9,  Textual support,  English

Record number: 9, Textual support number: 1 DEF

A supercell with "text-book" like features such as a well-defined hook echo on a radar scope and the precipitation core downwind of the wall cloud and rain free storm base.  2, record 9, English, - classic%20supercell

Record number: 9, Textual support number: 1 CONT

Supercell [is] a thunderstorm with a persistent rotating updraft. Supercells are rare, but are responsible for a remarkably high percentage of severe weather events-especially tornadoes, extremely large hail and damaging straight-line winds. They frequently travel to the right of the main environmental winds(i. e., they are right movers). Radar characteristics often(but not always) include a hook or pendant, bounded weak echo region(BWER), V-notch, mesocyclone, and sometimes a TVS [Tornado Vortex Signature]. Visual characteristics often include a rain-free base(with or without a wall cloud), tail cloud, flanking line, overshooting top, and back-sheared anvil, all of which normally are observed in or near the right rear or southwest part of the storm. Storms exhibiting these characteristics often are called classic supercells; however HP(High Precipitation) storms and LP(Low Precipitation) storms also are supercell varieties.  3, record 9, English, - classic%20supercell

Record number: 9, Textual support number: 2 CONT

The severe version of a worst-last storm is also a supercell type, and is either called a "classic supercell" (the standard supercell type) or an "LP (low-precipitation) supercell" - a dry-weather, high wind shear version. ... The classic supercell has a larger, darker appearance and accounts for most of the major tornado events everywhere.  4, record 9, English, - classic%20supercell

Record 9,  Textual support,  French

Record number: 9, Textual support number: 1 CONT

Les orages de queue qui sont violents sont aussi de type supercellulaire; on les appelle des orages supercellulaires classiques ou à faibles précipitations (caractérisés par la présence d'air sec et d'un fort cisaillement du vent). [...] Les orages supercellulaires classiques sont de plus grande étendue et plus sombres; ce sont eux qui produisent la plupart des tornades, quelle que soit la région.  1, record 9, French, - orage%20supercellulaire%20classique

Record 9,  Textual support,  Spanish

Record 10,  Textual support,  English

Record number: 10, Textual support number: 1 CONT

An issue of considerable interest is the so-called multicellular thunderstorm system, as opposed to supercells, which are often presumed to be unicellular. A form of multicellular convection that has already been simulated extensively is the squall line. The typical method for simulating this form of deep line-oriented convection has been to release a number of laterally-aligned IB’s. After the initial storms develop, their outflows merge, producing a line of convection resembling a squall line. Squall lines are not the only type of multicellular convection observed, however. In isolated multicell storms, a succession of updrafts is typical.  1, record 10, English, - multicellular%20thunderstorm%20system

Record number: 10, Textual support number: 1 OBS

Thunderstorms are often classified into a spectrum based on their cell structure : single cells, multicellular storms, and supercells. The type of storm depends on the instability and relative wind conditions at different layers of the atmosphere(shear). The "single-cell"(unicell) thunderstorm is [a] three-stage situation... usually lasting about 30 minutes from the start of significant precipitation. A severe unicell storm is often referred to as a pulse thunderstorm.... In a multicell thunderstorm, several thunderstorm cells merge into a larger system. The cloud becomes divided into updraft and downdraft regions separated by a gust front. The gust front may extend for several miles ahead of the storm, bringing with it increases in wind speed and atmospheric pressure, decreases in temperature, and shifts in wind direction. The storm itself will have different portions sequentually going through the various thunderstorm stages. In many cases the immature cells develop along a line known as a "flanking line, "resulting in what is known as a line multicell.  6, record 10, English, - multicellular%20thunderstorm%20system

Record number: 10, Textual support number: 2 OBS

storm system: Often refers to "thunderstorm system" (in French: "système orageux"), which is a frequent type of storm system but not the only one; an elliptic form which can be used when there is no risk of ambiguity.  3, record 10, English, - multicellular%20thunderstorm%20system

Record 10,  Textual support,  French

Record 10,  Textual support,  Spanish

Record 11,  Textual support,  English

Record number: 11, Textual support number: 1 DEF

The middle and most intense phase in the life cycle of a thunderstorm cell; begins when precipitation reaches Earth's surface and is characterized by both updrafts and downdrafts.  2, record 11, English, - mature%20stage

Record number: 11, Textual support number: 1 CONT

The life cycle of a thunderstorm cell can be divided into three stages which are determined by the magnitude and direction of the predominating vertical motions within the cell. These stages include (1) the cumulus stage, (2) the mature stage, and (3) the dissipation stage. ... The mature stage is characterized by the existence of both updrafts and downdrafts in the lower half of the cell. The start of this stage is marked when the rain first falls distinctly out of the bottom of the cloud. It is during this stage that the most intense lightning occurs, the heaviest rains are recorded at the surface, and the strongest winds are observed. If present, hail will occur during this stage.  3, record 11, English, - mature%20stage

Record 11,  Textual support,  French

Record number: 11, Textual support number: 1 CONT

Le stade de maturité commence lorsque les précipitations commencent à tomber de la base du nuage. [...] Ce stade de maturité constitue la période d'orage; il dure de quinze à vingt minutes. On y observe des éclairs soit au sein même du nuage (horizontaux, dits «crawler») soit dirigés vers le sol (éclairs Cloud-Ground ou CG) accompagnés de tonnerre et d'averses (de pluie, de neige ou de grêle en fonction des circonstances). Les températures sont plus basses dans les courants descendants en comparaison avec l'air environnant et contrastent spécialement avec les températures dans les courants ascendants [...]  3, record 11, French, - stade%20adulte

Record number: 11, Textual support number: 2 CONT

Un orage est composé de différentes cellules qui se trouvent à un stade de développement différent. Le cycle de vie d'une des cellules comporte trois stades : cumulus (ou naissance), adulte et dissipation. [...] Le stade adulte est [...] caractérisé par la présence simultanée de courants ascendants, de courants descendants et de pluie.  1, record 11, French, - stade%20adulte

Record 11,  Textual support,  Spanish

Record 12,  Textual support,  English

Record number: 12, Textual support number: 1 DEF

The final phase in the life cycle of a thunderstorm cell; features downdrafts throughout the system and vaporization of clouds.  2, record 12, English, - dissipation%20stage

Record number: 12, Textual support number: 1 CONT

The life cycle of a thunderstorm cell can be divided into three stages which are determined by the magnitude and direction of the predominating vertical motions within the cell. These stages include(1) the cumulus stage,(2) the mature stage, and(3) the dissipation stage.... The dissipating stage is characterized by weak downdrafts throughout the cell. In this stage there are no longer the updraft currents which provided the condensing water(precipitation) in the previous stage. When complete dissipation has occurred, only stratified clouds will remain.  1, record 12, English, - dissipation%20stage

Record 12,  Textual support,  French

Record number: 12, Textual support number: 1 CONT

Le stade de dissipation [est] caractérisé par des mouvements descendants. [...] Le stade de dissipation commence dès que les courants ascendants disparaissent et que les courants descendants ont envahi l'ensemble de la cellule. Le nuage commence à se dissiper. La dissipation totale ou la stratification intervient dès que la pluie (ou la neige) et les courants descendants cessent. Le sommet du nuage prend la forme caractéristique d'une enclume (cb incus) qui peut s'étendre horizontalement sur plusieurs kilomètres. Dès le début de ce stade, qui dure environ 30 minutes, les risques d'orage disparaissent. Lorsque les mouvements descendants cessent, les températures à l'intérieur de la cellule deviennent égales à celles de l'air environnant à même altitude.  2, record 12, French, - stade%20de%20dissipation

Record number: 12, Textual support number: 1 OBS

Un orage est composé de différentes cellules qui se trouvent à un stade de développement différent. Le cycle de vie d'une des cellules comporte trois stades : cumulus (ou naissance), adulte et dissipation.  3, record 12, French, - stade%20de%20dissipation

Record 12,  Textual support,  Spanish

Record 13,  Textual support,  English

Record number: 13, Textual support number: 1 DEF

A thunderstorm... in which negligible precipitation reaches the ground.  1, record 13, English, - dry%20storm

Record 13,  Textual support,  French

Record number: 13, Textual support number: 1 DEF

Orage électrique accompagné d'éclairs, ne déversant sur le sol qu'une pluie négligeable.  1, record 13, French, - orage%20sec

Record 13,  Textual support,  Spanish

Record number: 13, Textual support number: 1 DEF

Tormenta eléctrica sin precipitaciones.  2, record 13, Spanish, - tormenta%20seca

Record 14,  Textual support,  English

Record number: 14, Textual support number: 1 CONT

The precipitation from this cloud is very weak, and most rain evaporates before reaching the ground. But this causes one more severe feature : A dry downburst. Great damages to property and life in the Middle-East have occurred as a result of dry downbursts. The surface air under the alto-Cb is extremely hot and dry(humidity less than 10%). The rain falling from the thunderstorm under the downdraft evaporates as a result of the dry air. Evaporation causes the air to cool, which increases the speed of the downburst. Sustained winds can reach 160 km/h(100 mph) or more, for a few minutes. In Israel, the dry downbursts usually occur over the desert regions, in the south and east, when the humidity is very low.  2, record 14, English, - dry%20downburst

Record number: 14, Textual support number: 2 CONT

Downbursts occur in regions of a severe thunderstorm where the air is accelerated downward by exceptionally strong evaporative cooling occurs (a dry downburst) or by very heavy rain which drags dry air down with it (a wet downburst). When the rapidly descending air strikes the ground, it spreads outward in all directions in a circle, like a fast-running faucet hitting the sink bottom.  3, record 14, English, - dry%20downburst

Record 14,  Textual support,  French

Record number: 14, Textual support number: 1 CONT

Une rafale descendante sèche est produite par l'évaporation des précipitations dans un environnement aux basses couches très sèches.  1, record 14, French, - rafale%20descendante%20s%C3%A8che

Record 14,  Textual support,  Spanish