532:(TVS) or the tornado detection algorithm (TDA). TVS is then an extremely strong mesocyclone found at very low level and extending over a deep layer of the thunderstorm, not the actual tornadic circulation. The TVS is, however, indicative of a likely tornado or an incipient tornado. The couplet and TVS typically precede tornado formation by 10–30 minutes but may occur at nearly the same time or precede the tornado by 45 minutes or more. Polarimetric radar can discern meteorological and nonmeteorological and other characteristics of hydrometeors that are helpful to tornado detection and nowcasting. Nonmeteorological reflectors co-located with a couplet, can confirm that a tornado has likely occurred and lofted debris. An area of high reflectivity, or debris ball, may also be visible on the end of the hook. Either the polarimetric data or debris ball are formally known as the
504:. A V-notch or "flying eagle echo" tend to be most pronounced with intense classic supercells, the type of supercell that produces most of the strongest, largest, and longest lived tornadoes. This is not to be confused with an inflow notch; which is a lower level indentation in the precipitation where there is little to no reflectivity, indicative of strong, organized inflow and a severe storm that is most likely a supercell. The rear inflow notch (or weak echo channel) occurs to the east or north of a mesocyclone and hook echo. Forward inflow notches also occur, particularly on high-precipitation supercells (HP) and quasi-linear convective systems (QLCS).
770:
determine whether a storm will be enhanced by its presence or the inflow be choked off thus weakening and possibly killing the storm. Thunderstorms may move along slow-moving or stationary outflow boundaries and tornadoes are more likely; whereas fast-moving gust fronts in many cases weaken thunderstorms after impact and are less likely to produce tornadoes—although brief tornadoes may occur at the time of impact. Fast-moving gust fronts may eventually decelerate and become slow-moving or stationary outflow boundaries with the characteristic "agitated area" of cumulus fields previously mentioned.
439:
269:
radar, due to curvature of Earth and the spread of the beam with distance. Therefore, when far from a radar, only precipitations and velocities high in the storm are observed. The important areas might not then be sampled or the resolution of the data might be poor. Also, some meteorological situations leading to tornadogenesis are not readily detectable by radar and on occasion tornado development may occur more quickly than radar can complete a scan and send the batch of data.
399:
336:. Under the storm and closer to where most tornadoes are found, evidence of a supercell and likelihood of a tornado includes inflow bands (particularly when curved) such as a "beaver tail", and other clues such as strength of inflow, warmth and moistness of inflow air, how outflow- or inflow-dominant a storm appears, and how far is the forward flank precipitation core from the wall cloud. Tornadogenesis is most likely at the interface of the updraft and
585:
278:
455:
519:(towards or away from the radar) of the winds in a storm, and so can spot evidence of rotation in storms from more than a hundred miles (160 km) away. A supercell is characterized by a mesocyclone, which is usually first observed in velocity data as a tight, cyclonic structure in the middle levels of the thunderstorm. If it meets certain requirements of strength, duration, and
118:
665:
493:) may then form above and enclosing the WER. A BWER is found near the top of the updraft and nearly or completely surrounded by strong reflectivity, and is indicative of a supercell capable of cyclic tornadogenesis. A mesocyclone may descend or a tornado may form in the lower level of the storm simultaneously as the mesocyclone forms.
797:
satellite data was delayed, but continues to be useful in detecting thunderstorms in stages of development before there is a substantial radar signature or for areas where radar data is lacking. Coming advances in research and observations should improve forecasts of severe weather and increase warning time.
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appear on satellite pictures. This line is likely the point of further convection and storms, especially if it coincides with fronts from other thunderstorms in the vicinity. One can notice it at the leading edge of a squall line, in the southeastern quadrant of a typical supercell (in the northern
651:
of a dry air parcel injected into the storm, plus de motion of the convective cell. S. R. Stewart, from NWS, has published in 1991 an equation relating VIL and the echo tops that give the potential for surface gust using this concept. This is a predictive result that gives a certain lead time. With
268:
from an observer can either verify the threat or determine it is not imminent. The spotter's ability to see what these remote sensing devices cannot is especially important as distance from a radar site increases, because the radar beam becomes progressively higher in altitude further away from the
796:
Lightning data is useful in suggesting intensity and organization of convective cells as well trends in thunderstorm activity (particularly growth, and to a lesser degree, decay). It is also useful in the early stages of thunderstorm development. This was especially true when visible and infrared
642:
is linked to three forces in the vertical, namely perturbation pressure gradient force, buoyancy force and precipitation loading. The pressure gradient force was neglected as it has significant effect only on the updraft in supercells. With this assumption and other simplifications (e.g. requiring
600:
in the reflectivity pattern is an important clue. It is an area of weak reflectivity extending away from the radar immediately behind a thunderstorm with hail. It is caused by radiation from the radar bouncing from hailstone to hailstone or the ground before being reflected back to the radar. The
481:. This is an area within the thunderstorm where precipitation should be occurring but is "pulled" aloft by a very strong updraft. The weak echo region is characterized by weak reflectivity with a sharp gradient to strong reflectivity above it and partially surrounding the sides. The region of the
700:
soundings of the day, and the visible (vis: 0.5-1.1 ÎĽm) ones will show the shape of the storms by its brightness and shadow produced. Meteorologists can extract information about the development stage and subsequent traits of thunderstorms by recognizing specific signatures in both domains.
359:
dips and in nearly all cases by the time it reaches halfway down, a surface swirl has already developed, signifying a tornado is on the ground before condensation connects the surface circulation to the storm. Tornadoes may also occur without wall clouds, under flanking lines, and on the leading
788:
hazard). Currently, most lightning data provided in real-time is from terrestrial sources, specifically, networks of ground-based sensors, although airborne sensors are also in operation. Most of these only provide latitude & longitude, time, and polarity of cloud-to-ground strikes within a
604:
What is needed is a knowledge of the water content in the thunderstorm, the freezing level and the height of the summit of the precipitation. One way of calculating the water content is to transform the reflectivities in rain rate at all levels in the clouds and to sum it up. This is done by an
769:
hours or days after convection and can pinpoint areas of favored thunderstorm development, the possible direction of movement, and even likelihood for tornadoes. The speed of forward movement of the outflow boundary or gust front to some degree modulates the likelihood of tornadoes and helps
563:
network, may provide enhanced warning of tornadoes and severe winds and hail associated with the hook echo due to distinct precipitation drop characteristics. Polarimetric radar boosts precipitation observation and prediction, especially rainfall rates, hail detection, and distinguishing
527:
detection algorithm (MDA). Tornadic signatures are indicated by a cyclonic inbound-outbound velocity couplet, where strong winds flowing in one direction and strong winds flowing in the opposite direction are occurring in very close proximity. The algorithm for this is the
748:
is often intersecting the line and its dry air introduced into the cloud is negatively unstable. This results in drying of the cloudy air in the region where the jet plunge groundward. On the back edge of the line, this shows as clear notches where one can find stronger
136:
Rigorous attempts to warn of tornadoes began in the United States in the mid-20th century. Before the 1950s, the only method of detecting a tornado was by someone seeing it on the ground. Often, news of a tornado would reach a local weather office after the storm.
601:
time delay between the backscattered radiation from the storm and the one with multiple paths causes the reflectivity from the hail to appear to come from a farther range than the actual storm. However, this artefact is visible mostly for extremely large hail.
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Visible imagery permits the most detailed imagery whereas infrared imagery has the advantage of availability at night. Sensors on satellites can also detect emissions from water vapor (WV: 6-7 ÎĽm), but mostly in the middle to upper levels of the
789:
limited range. Increasing in sophistication and availability, and affording data for a very wide area, are satellite-based lightning detectors which initially included optical sensors indicating flash rates and horizontal location but now
611:, or VIL. This value represent the total amount of liquid water in the cloud that is available. If the cloud would rain out completely, it would be the amount of rain falling on the ground and one can estimate with VIL the potential for
390:. Radar is always available, in places and times where spotters are not, and can also see features that spotters cannot, in the darkness of night and processes hidden within the cloud as well as invisible processes outside the cloud.
212:, and ordinary citizens. When severe weather is anticipated, local weather service offices request that these spotters look out for severe weather, and report any tornadoes immediately, so that the office can issue a timely warning.
264:, and satellite images, do not detect tornadoes or hail, only indications that the storm has the potential. Radar and satellite data interpretation will usually give a warning before there is any visual evidence of such events, but
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forming at the overshooting top fan out in a V shape as cloud matter is blown downwind at that level. Both features can be seen on visible satellite imagery, during daytime, by the shadows they cast on surrounding clouds.
626:
in the cloud, is a good indicator of the presence of hail when it reach 3.5. This is a crude yes/no index and other algorithms have been developed involving VIL and the freezing level height. More recently,
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and CASA, would further improve observations and forecasts by increasing the temporal and spatial resolution of scans in the former as well as providing low-level radar data over a wide area in the latter.
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Usually in conjunction with data sources such as weather radar and satellites, lightning detection systems are sometimes utilized to pinpoint where thunderstorms are occurring (and to identify
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in a supercell or a multicellular thunderstorm. As for tornadoes, BWER detection and a tilted updraft are indicative of that updraft but does not lead to predict hail. The presence of a
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will be noticeable by a colder temperature region in the thunderstorm on infrared images. Another signature associated with this situation is the
Enhanced-V feature where the cold
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at the surface. These kinds of lines often have a very characteristic undulating pattern caused by the interference of the gusts fronts coming from different parts of the line.
485:
lofted above the WER is the echo overhang consisting of precipitation particles diverging from the storm's summit that descend as they are carried downwind. Within this area, a
656:
happening, but since this a small scale feature, detection algorithms have been developed to point convergence and divergence areas under a thunderstorm on the radar display.
57:
The ability to discern the presence of deep moist convection in a storm significantly improves meteorologists' capacity to predict and monitor associated phenomena such as
1818:
756:
Finally, in any type of thunderstorm, the surface cold pool of air associated with the downdraft will stabilize the air and form a cloud-free area that will end along the
1829:
588:
Vertical cross-section of a thunderstorm at the top and VIL value of 63 kg/m with that cell at the bottom (red one), giving potential for hail, downpour, and/or downdraft
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Usually, spotters are trained by the NWS on behalf of their respective organizations, and they report to them. The organizations activate public warning systems such as
1202:
1152:
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occludes precipitation around the mesocyclone and is also indicative of a probable tornado (tornadogenesis usually ensues shortly after the RFD reaches the surface).
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are associated with tornadoes. By recognizing these radar signatures, meteorologists could detect thunderstorms likely producing tornadoes from dozens of miles away.
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network in the U.S., the probability of detection of tornadoes increased substantially, the average lead time rose from four minutes to thirteen minutes, and a 2005
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1132:
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integrate radar data with reports from the field and knowledge of the meteorological environment. Radar analysis is augmented by automated detection systems called
474:. Meteorologists first look at the atmospheric environment as well as changes thereof, and once storms develop, storm motion and interaction with the environment.
724:(EL) before being pulled back by negative buoyancy. This means the cloud tops will reach higher levels than the surrounding cloud in the updraft region. This
343:
Only wall clouds that rotate spawn tornadoes, and usually precede the tornado by five to thirty minutes. Rotating wall clouds are the visual manifestation of a
1114:
Chance Hayes, National
Weather Service Wichita, Kansas. "Storm Fury on the Plains." Storm Spotter Training. 4H Building, Salina, Kansas. 22 Feb. 2010. Lecture.
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the environment of the air parcel to be static on the time scale of the downdraft). The resulting momentum equation is integrated over height to yield the
224:
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The prediction of pulse-type thunderstorm gusts using vertically integrated liquid water content (VIL) and the cloud top penetrative downdraft mechanism
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are available and used mostly by parks and other outdoor recreational facilities, or meteorologists contracted to provide weather information for them.
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However, the reflectivities are greatly enhanced by hail and VIL is greatly overestimating the rain potential in presence of hail. On the other hand,
1906:
250:
1757:
Instruments and
Techniques for Thunderstorm Observation and Analysis (Thunderstorms: a Social, Scientific, and Technological Documentary, Vol 3)
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report estimates that as a result of improved warnings that there are 45 percent fewer fatalities and 40 percent fewer injuries annually. Dual-
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to identify and report key features of storms which indicate severe hail, damaging winds, and tornadoes, as well as damage itself and
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However, with the advent of weather radar, areas near a local office could get advance warning of severe weather. The first public
1178:
1547:
Haerter, Jan O.; Böing, Steven J.; Henneberg, Olga; Nissen, Silas Boye (May 23, 2019). "Circling in on
Convective Organization".
1416:
1302:
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500:(precipitation intensity) data, a tight echo gradient (particularly on the inflow area) and a fan shape generally indicate a
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228:
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Personal lightning detection systems are also available, which may provide strike time, azimuth, and distance. In addition,
382:, which remains the main method of detecting signatures likely associated with tornadoes and other severe phenomenons as
126:
837:
607:
1896:
801:
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1456:"Development of Warning Criteria for Severe Pulse Thunderstorms in the Northeastern United States using the WSR-88D"
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An early step in a storm organizing into a tornado producer is the formation of a weak echo region (WER) with a
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meteorologists have found that the VIL density, that is to say VIL divided by the maximum height of the 18
1911:
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220:
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27:
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adjacent to a corner of a wall cloud. A tornado often occurs as this happens or shortly after; first, a
325:
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to users such as emergency management, storm spotters and chasers, the media, and the general public.
1613:
1566:
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997:
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1061:
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779:
317:
313:. The vast majority of intense tornadoes occur with a wall cloud on the backside of a supercell.
39:
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network. There are more than 230,000 trained
Skywarn weather spotters across the United States.
1602:"Lightning and Severe Weather: A Comparison between Total and Cloud-to-Ground Lightning Trends"
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hemisphere), or different regions around other thunderstorms. They may also be visible as an
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321:
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869:. Meteorological Monographs. Vol. 28, No. 50. Boston, MA: American Meteorological Society.
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capable weather radar stations are used. These devices are capable of measuring the radial
1833:
1822:
1722:
1455:
1228:
1093:
1065:
790:
373:
141:
1671:
The
Tornado: Its Structure, Dynamics, Prediction, and Hazards (Geophysical Monograph #79)
709:, as it illustrates the placement and movement of air masses and of moisture, as well as
1617:
1570:
1515:
1001:
957:
942:"Early Severe Thunderstorm Forecasting and Research by the United States Weather Bureau"
913:
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receivers that can identify intra-cloud flashes with the addition of altitude, as well.
760:. This mesoscale front, when moving into a warm and unstable air mass, will lift it and
1886:
705:, so thunderstorms are only seen after being well developed. It is, however, useful in
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1019:
865:(2001). "Severe Convective Storms – An Overview". In Doswell, Charles A. III (ed.).
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185:
43:
31:
30:(DMC). DMC describes atmospheric conditions producing single or clusters of large
1865:
1428:
1340:
454:
1805:
1500:"A Quantitative Analysis of the Enhanced-V Feature in Relation to Severe Weather"
245:
In Europe, several nations are organizing spotter networks under the auspices of
54:. Those two types of clouds can produce severe weather at the surface and aloft.
741:
702:
612:
556:
524:
344:
293:
Storm spotters are trained to discern whether a storm seen from a distance is a
189:
173:
74:
23:
898:"Storm Spotting and Public Awareness since the First Tornado Forecasts of 1948"
672:
in the eastern United States with arrows pointing to the enhanced-v signatures.
1859:
745:
693:
653:
333:
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features such as a hard and vigorous updraft tower, a persistent and/or large
310:
282:
94:
1626:
1601:
696:) images permit estimation of the top height of the clouds, according to the
1843:
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750:
729:
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of severe convective and tornadic storms. These images are available in the
639:
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of the parcel on descending to the surface and is found to be the negative
442:
A classic hook echo. The tornado associated with this echo was part of the
347:. Barring a low-level boundary, tornadogenesis is highly unlikely unless a
105:, consisting of prediction, detection, and dissemination of information on
720:. The rising air parcels in that column accelerate and will overshoot the
664:
1578:
1498:
Brunner, Jason C.; S.A. Ackerman; A.S. Bachmeier; R.M. Rabin (Aug 2007).
697:
689:
512:
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Evidence of a supercell comes from the storm's shape and structure, and
717:
668:
Infrared weather satellite image at 23Z 7 April 2006 associated with a
652:
the
Doppler velocity data, the meteorologist can see the downdraft and
593:
403:
298:
239:
181:
177:
90:
58:
51:
1524:
1499:
223:, and forward the reports to the NWS, which does directly disseminate
1693:
Severe
Convective Storms (Meteorological Monographs, Vol. 28, No. 50)
1389:"Tornado identification and forewarning with VHF windprofiler radars"
560:
548:
261:
235:
122:
1735:
Significant
Tornadoes 1680-1991: A Chronology and Analysis of Events
1401:
1388:
360:
edge. Spotters monitor all areas of a storm and their surroundings.
1561:
1033:
1669:
Church, C.; D. Burgess; C. Doswell; et al., eds. (Dec 1993).
663:
583:
453:
437:
397:
352:
276:
116:
1737:. St. Johnsbury, VT: The Tornado Project of Environmental Films.
1651:
Severe
Convective Storms and Tornadoes: Observations and Dynamics
631:
of weather radar have shown promising direct detection of hail.
552:
383:
329:
77:. It relies on direct eyewitness observations, for example from
70:
66:
62:
1600:
Schultz, Christopher J.; W.A. Peterson; L.D. Carey (Oct 2011).
576:
may also provide detection capabilities for tornadic activity.
1052:
1050:
410:, showing four products used to detect active tornadoes: high
305:. Under the updraft is a rain-free base, and the next step of
242:, helps spot severe weather, with more than 1,000 volunteers.
1790:
1362:
351:
occurs, which is usually visibly evidenced by evaporation of
93:
measurements are used for direct detection as well, notably,
1799:
1427:
Forecast Office Albany, New York. June 2009. Archived from
1011:
10.1175/1520-0493(2002)130<0852:HEARFD>2.0.CO;2
967:
10.1175/1520-0434(1992)007<0564:ESTFAR>2.0.CO;2
923:
10.1175/1520-0434(1999)014<0544:SSAPAS>2.0.CO;2
340:, and requires a "balance" between the outflow and inflow.
676:
Most populated areas of the earth are now well covered by
564:
precipitation types. Proposed radar technologies, such as
238:, a similar network of volunteer weather watchers, called
1085:
458:
Vertical cross-section through a supercell exhibiting a
260:
Storm spotters are needed because radar systems such as
297:. They typically look to its rear, the main region of
26:
observation, and short-term prediction, of deep moist
466:
In short-term prediction and detection of tornadoes,
253:(TORRO) has maintained a network of spotters in the
1281:"Precipitation properties of supercell hook echoes"
1844:An Introduction to Storm Observation and Reporting
378:Today, most developed countries have a network of
986:"Hook Echoes and Rear-Flank Downdrafts: A Review"
888:
886:
834:, a pioneer in the field of forecasting tornadoes
430:, and the strong opposing velocity values form a
1454:Carl S. Cerniglia; Warren R. Snyder (Jun 2002).
507:In the United States and a few other countries,
1695:. Boston, MA: American Meteorological Society.
1175:National Oceanic and Atmospheric Administration
1166:Doswell, Moller, Anderson; et al. (2005).
1133:National Oceanic and Atmospheric Administration
1673:. Washington, DC: American Geophysical Union.
1124:Edwards, Moller, Purpura; et al. (2005).
634:VIL can be used to estimate the potential for
8:
1759:. Norman, OK: University of Oklahoma Press.
1201:: CS1 maint: multiple names: authors list (
1151:: CS1 maint: multiple names: authors list (
1850:An Online Meteorology Guide: Severe Storms
1110:
1108:
1106:
1104:
1102:
1625:
1560:
1523:
1487:. Technical Memorandum, NWS SR-136. NOAA.
1400:
1058:"Tornado Detection at Environment Canada"
1009:
965:
921:
152:in 1952. In 1953 it was confirmed that
1217:"Questions and Answers about Tornadoes"
896:; A.R. Moller; H.E. Brooks (Aug 1999).
854:
251:Tornado and Storm Research Organisation
1862:(NOAA Technical Memorandum NWS SR-145)
1718:
1708:
1449:
1447:
1445:
1194:
1144:
1868:(NWS JetStream Online Weather School)
1387:Hocking, Anna; W. K. Hocking (2017).
572:In certain atmospheric environments,
168:(NWS) increased its efforts to train
7:
289:clear slot evident to its left rear.
1860:Weather Glossary for Storm Spotters
559:radar, being implemented to the US
1279:Kumjian, Matthew R. (2011-10-05).
713:and areas of vorticity and lifts.
144:were issued in 1950 and the first
14:
1285:Electron. J. Sev. Storms Meteorol
1225:National Severe Storms Laboratory
814:National Severe Storms Laboratory
716:Severe storms have a very strong
692:domains. The infrared (IR: 10-13
408:2021 Naperville–Woodridge tornado
131:1965 Twin Cities tornado outbreak
1806:Supercell Structure and Dynamics
1800:Warning Decision Training Branch
1689:Doswell, Charles A. III (Editor)
1465:Forecast Office Albany, New York
1168:"Advanced Spotters' Field Guide"
826:Warning Decision Training Branch
547:After the implementation of the
446:. It reached F5 strength on the
324:, a hard anvil (especially when
1907:Weather warnings and advisories
1816:Tornadogenesis cascade paradigm
1184:from the original on 2006-08-23
309:is the formation of a rotating
1838:San Francisco State University
1791:NOAA Hazardous Weather Testbed
444:1999 Oklahoma tornado outbreak
422:returns, when paired with low
229:NOAA Weather Radio All Hazards
180:, and the spotters were local
1:
1882:Severe weather and convection
1126:"Basic Spotters' Field Guide"
592:Hail forms in a very intense
125:) displaying supercells over
1549:Geophysical Research Letters
1303:"Polarimetric Doppler Radar"
1227:. 2006-11-15. Archived from
1064:. 2004-06-02. Archived from
838:Tropical cyclone observation
802:lightning prediction systems
670:significant tornado outbreak
608:Vertically integrated liquid
580:Hail, downburst and downpour
434:. The tornado was rated EF3.
101:stations. It is part of the
1654:. London: Springer-Praxis.
707:convective storm prediction
332:), and a corkscrew look or
328:against strong upper level
1928:
1036:. National Weather Service
777:
367:
20:Convective storm detection
16:Meteorological observation
1250:"Radar Operations Center"
1096:, retrieved on 2007-05-18
540:feature is formed as the
530:tornadic vortex signature
424:differential reflectivity
176:. The program was called
164:In the mid-1970s, the US
103:integrated warning system
1796:Tornado Warning Guidance
1627:10.1175/WAF-D-10-05026.1
1463:National Weather Service
1425:National Weather Service
867:Severe Convective Storms
620:National Weather Service
534:tornado debris signature
487:bounded weak echo region
432:tornado vortex signature
428:tornado debris signature
225:information and warnings
166:National Weather Service
127:Minneapolis – Saint Paul
121:1960s radar technology (
1221:A Severe Weather Primer
894:Doswell, Charles A. III
863:Doswell, Charles A. III
820:Storm Prediction Center
420:correlation coefficient
338:forward flank downdraft
198:amateur radio operators
42:, the latter producing
1854:University of Illinois
1483:Stewart, S.R. (1991).
673:
589:
463:
451:
435:
290:
221:Emergency Alert System
133:
667:
587:
457:
441:
401:
280:
120:
1646:Bluestein, Howard B.
1579:10.1029/2019GL082092
1333:"Phased Array Radar"
1313:on 10 September 2012
638:, too. A convective
426:returns, indicate a
349:rear flank downdraft
287:rear flank downdraft
206:emergency management
34:clouds ranging from
1731:Grazulis, Thomas P.
1618:2011WtFor..26..744S
1571:2019GeoRL..46.7024H
1516:2007WtFor..22..853B
1260:on 15 December 2016
1002:2002MWRv..130..852M
958:1992WtFor...7..564G
914:1999WtFor..14..544D
843:Weather forecasting
774:Lightning detection
680:, which aid in the
515:, including radial
406:radar image of the
150:convective outlooks
99:surface observation
1897:Weather prediction
1832:2005-11-09 at the
1821:2007-07-07 at the
1721:has generic name (
1092:2009-09-17 at the
1062:Environment Canada
1034:"What is SKYWARN?"
982:Markowski, Paul M.
780:Lightning detector
678:weather satellites
674:
590:
523:, it may trip the
464:
452:
436:
291:
182:sheriff's deputies
134:
32:vertical extension
1902:Radar meteorology
1781:Tornado Detection
1555:(12): 7024–7034.
1525:10.1175/WAF1022.1
938:Galway, Joseph G.
722:equilibrium level
660:Satellite imagery
629:dual polarization
605:algorithm called
257:since the 1970s.
194:ambulance drivers
36:cumulus congestus
1919:
1770:
1748:
1726:
1720:
1716:
1714:
1706:
1684:
1665:
1632:
1631:
1629:
1606:Weather Forecast
1597:
1591:
1590:
1564:
1544:
1538:
1537:
1527:
1504:Weather Forecast
1495:
1489:
1488:
1480:
1474:
1473:
1471:
1470:
1460:
1451:
1440:
1439:
1437:
1436:
1413:
1407:
1406:
1404:
1393:Atmos. Sci. Lett
1384:
1378:
1377:
1375:
1373:
1359:
1353:
1352:
1350:
1348:
1339:. Archived from
1329:
1323:
1322:
1320:
1318:
1309:. Archived from
1299:
1293:
1292:
1276:
1270:
1269:
1267:
1265:
1256:. Archived from
1246:
1240:
1239:
1237:
1236:
1213:
1207:
1206:
1200:
1192:
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1189:
1183:
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1163:
1157:
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1115:
1112:
1097:
1083:
1077:
1076:
1074:
1073:
1054:
1045:
1044:
1042:
1041:
1030:
1024:
1023:
1013:
990:Mon. Weather Rev
978:
972:
971:
969:
946:Weather Forecast
934:
928:
927:
925:
902:Weather Forecast
890:
881:
880:
859:
832:Robert C. Miller
767:outflow boundary
744:, the mid-level
726:overshooting top
322:overshooting top
142:tornado warnings
46:associated with
1927:
1926:
1922:
1921:
1920:
1918:
1917:
1916:
1872:
1871:
1834:Wayback Machine
1823:Wayback Machine
1777:
1767:
1751:
1745:
1729:
1717:
1707:
1703:
1687:
1681:
1668:
1662:
1644:
1641:
1639:Further reading
1636:
1635:
1599:
1598:
1594:
1546:
1545:
1541:
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1496:
1492:
1482:
1481:
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1466:
1458:
1453:
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1443:
1434:
1432:
1415:
1414:
1410:
1402:10.1002/asl.795
1386:
1385:
1381:
1371:
1369:
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1331:
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1234:
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1215:
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1187:
1185:
1181:
1170:
1165:
1164:
1160:
1143:
1137:
1135:
1128:
1123:
1122:
1118:
1113:
1100:
1094:Wayback Machine
1088:, Archived at:
1084:
1080:
1071:
1069:
1056:
1055:
1048:
1039:
1037:
1032:
1031:
1027:
980:
979:
975:
936:
935:
931:
892:
891:
884:
877:
861:
860:
856:
851:
810:
791:radio frequency
782:
776:
662:
582:
402:Dual-polarized
396:
376:
374:Lemon technique
368:Main articles:
366:
275:
273:Visual evidence
162:
146:tornado watches
115:
17:
12:
11:
5:
1925:
1923:
1915:
1914:
1909:
1904:
1899:
1894:
1889:
1884:
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1873:
1870:
1869:
1863:
1857:
1847:
1841:
1813:
1803:
1793:
1788:
1776:
1775:External links
1773:
1772:
1771:
1765:
1753:Kessler, Edwin
1749:
1743:
1727:
1701:
1685:
1679:
1666:
1661:978-3642053801
1660:
1640:
1637:
1634:
1633:
1592:
1539:
1490:
1475:
1441:
1408:
1379:
1367:casa.umass.edu
1354:
1343:on 24 May 2008
1324:
1294:
1271:
1241:
1208:
1158:
1116:
1098:
1086:Skywarn Europe
1078:
1046:
1025:
973:
929:
882:
875:
853:
852:
850:
847:
846:
845:
840:
835:
829:
823:
817:
809:
806:
778:Main article:
775:
772:
762:cumulus clouds
661:
658:
645:kinetic energy
581:
578:
574:wind profilers
479:tilted updraft
468:meteorologists
395:
392:
380:weather radars
365:
362:
307:tornadogenesis
274:
271:
255:United Kingdom
247:Skywarn Europe
186:state troopers
174:flash flooding
170:storm spotters
161:
160:Storm spotting
158:
114:
111:
107:severe weather
83:remote sensing
79:storm spotters
75:flash flooding
24:meteorological
15:
13:
10:
9:
6:
4:
3:
2:
1924:
1913:
1912:Storm chasing
1910:
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1900:
1898:
1895:
1893:
1890:
1888:
1885:
1883:
1880:
1879:
1877:
1867:
1866:Thunderstorms
1864:
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1779:
1778:
1774:
1768:
1766:0-8061-2117-3
1762:
1758:
1754:
1750:
1746:
1744:1-879362-03-1
1740:
1736:
1732:
1728:
1724:
1712:
1704:
1702:1-878220-41-1
1698:
1694:
1690:
1686:
1682:
1680:0-87590-038-0
1676:
1672:
1667:
1663:
1657:
1653:
1652:
1647:
1643:
1642:
1638:
1628:
1623:
1619:
1615:
1612:(5): 744–55.
1611:
1607:
1603:
1596:
1593:
1588:
1584:
1580:
1576:
1572:
1568:
1563:
1558:
1554:
1550:
1543:
1540:
1535:
1531:
1526:
1521:
1517:
1513:
1510:(4): 853–72.
1509:
1505:
1501:
1494:
1491:
1486:
1479:
1476:
1464:
1457:
1450:
1448:
1446:
1442:
1431:on 2012-10-07
1430:
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1295:
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1272:
1259:
1255:
1251:
1245:
1242:
1231:on 2012-08-09
1230:
1226:
1222:
1218:
1212:
1209:
1204:
1198:
1180:
1176:
1169:
1162:
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1154:
1148:
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1127:
1120:
1117:
1111:
1109:
1107:
1105:
1103:
1099:
1095:
1091:
1087:
1082:
1079:
1068:on 2010-04-07
1067:
1063:
1059:
1053:
1051:
1047:
1035:
1029:
1026:
1021:
1017:
1012:
1007:
1003:
999:
996:(4): 852–76.
995:
991:
987:
983:
977:
974:
968:
963:
959:
955:
952:(4): 564–87.
951:
947:
943:
939:
933:
930:
924:
919:
915:
911:
908:(4): 544–57.
907:
903:
899:
895:
889:
887:
883:
878:
876:1-878220-41-1
872:
868:
864:
858:
855:
848:
844:
841:
839:
836:
833:
830:
827:
824:
821:
818:
815:
812:
811:
807:
805:
803:
798:
794:
792:
787:
781:
773:
771:
768:
763:
759:
754:
752:
747:
743:
739:
738:multicellular
734:
731:
727:
723:
719:
714:
712:
708:
704:
699:
695:
691:
687:
683:
679:
671:
666:
659:
657:
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646:
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637:
632:
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621:
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609:
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595:
586:
579:
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567:
562:
558:
554:
550:
545:
543:
539:
535:
531:
526:
522:
518:
514:
510:
505:
503:
499:
494:
492:
488:
484:
483:precipitation
480:
475:
473:
469:
461:
456:
449:
445:
440:
433:
429:
425:
421:
417:
413:
409:
405:
400:
393:
391:
389:
385:
381:
375:
371:
370:Weather radar
363:
361:
358:
354:
350:
346:
341:
339:
335:
331:
327:
323:
319:
314:
312:
308:
304:
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296:
288:
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279:
272:
270:
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263:
258:
256:
252:
248:
243:
241:
237:
232:
230:
226:
222:
218:
213:
211:
210:storm chasers
207:
203:
202:civil defense
199:
195:
191:
187:
183:
179:
175:
171:
167:
159:
157:
155:
151:
147:
143:
138:
132:
128:
124:
119:
112:
110:
108:
104:
100:
97:reports from
96:
92:
88:
87:weather radar
85:, especially
84:
80:
76:
72:
68:
64:
60:
55:
53:
49:
45:
44:thunderstorms
41:
37:
33:
29:
25:
21:
1756:
1755:(Sep 1988).
1734:
1733:(Jul 1993).
1719:|first=
1692:
1691:(Nov 2001).
1670:
1650:
1609:
1605:
1595:
1552:
1548:
1542:
1507:
1503:
1493:
1484:
1478:
1467:. Retrieved
1433:. Retrieved
1429:the original
1420:
1417:"Hail spike"
1411:
1392:
1382:
1370:. Retrieved
1366:
1363:"UMass CASA"
1357:
1345:. Retrieved
1341:the original
1336:
1327:
1315:. Retrieved
1311:the original
1306:
1297:
1288:
1284:
1274:
1262:. Retrieved
1258:the original
1254:roc.noaa.gov
1253:
1244:
1233:. Retrieved
1229:the original
1220:
1211:
1186:. Retrieved
1161:
1136:. Retrieved
1119:
1081:
1070:. Retrieved
1066:the original
1038:. Retrieved
1028:
993:
989:
984:(Apr 2002).
976:
949:
945:
940:(Dec 1992).
932:
905:
901:
866:
857:
799:
795:
783:
755:
742:squall lines
735:
715:
675:
633:
617:
606:
603:
591:
571:
566:phased array
557:polarization
546:
506:
498:reflectivity
495:
476:
465:
448:Fujita scale
412:reflectivity
377:
357:funnel cloud
342:
315:
292:
266:ground truth
259:
244:
233:
227:through its
214:
208:) spotters,
190:firefighters
163:
139:
135:
102:
69:, and heavy
56:
40:cumulonimbus
19:
18:
740:storms and
703:troposphere
654:gust fronts
613:flash flood
536:(TDS). The
525:mesocyclone
414:returns in
345:mesocyclone
326:backsheared
318:cloud tower
281:A rotating
154:hook echoes
129:during the
73:leading to
1876:Categories
1562:1810.05518
1469:2008-10-03
1435:2009-01-10
1291:(5): 1–21.
1235:2007-07-05
1188:2016-11-30
1138:2016-11-30
1072:2007-03-16
1040:2007-02-27
849:References
758:gust front
751:downdrafts
746:jet stream
730:cloud tops
711:shortwaves
682:nowcasting
598:hail spike
472:algorithms
388:downbursts
334:striations
311:wall cloud
283:wall cloud
95:wind speed
28:convection
1827:schematic
1711:cite book
1587:181406163
1534:122014950
786:lightning
640:downdraft
636:downburst
538:hook echo
521:vorticity
517:direction
502:supercell
394:Tornadoes
295:supercell
81:; and on
65:, strong
59:tornadoes
48:lightning
1830:Archived
1819:Archived
1648:(2013).
1421:Glossary
1337:noaa.gov
1307:noaa.gov
1197:cite web
1179:Archived
1147:cite web
1090:Archived
1020:54785955
808:See also
698:air mass
690:infrared
513:velocity
418:and low
249:and the
219:and the
61:, large
1892:Tornado
1614:Bibcode
1567:Bibcode
1512:Bibcode
1372:21 June
1347:21 June
1317:21 June
1264:21 June
998:Bibcode
954:Bibcode
910:Bibcode
718:updraft
686:visible
594:updraft
549:WSR-88D
509:Doppler
404:WSR-88D
299:updraft
240:Canwarn
178:Skywarn
113:History
91:in situ
89:. Some
52:thunder
22:is the
1763:
1741:
1699:
1677:
1658:
1585:
1532:
1018:
873:
828:(WDTB)
816:(NSSL)
561:NEXRAD
303:inflow
262:NEXRAD
236:Canada
217:sirens
123:WSR-57
1887:Storm
1846:(NWS)
1798:(NWS
1583:S2CID
1557:arXiv
1530:S2CID
1459:(PDF)
1182:(PDF)
1171:(PDF)
1129:(PDF)
1016:S2CID
822:(SPC)
364:Radar
353:cloud
330:winds
285:with
204:(now
67:winds
1825:and
1785:NSSL
1761:ISBN
1739:ISBN
1723:help
1697:ISBN
1675:ISBN
1656:ISBN
1374:2017
1349:2017
1319:2017
1266:2017
1203:link
1153:link
871:ISBN
688:and
649:CAPE
553:NOAA
491:BWER
460:BWER
386:and
384:hail
372:and
301:and
148:and
71:rain
63:hail
50:and
1810:NWS
1622:doi
1575:doi
1520:doi
1397:doi
1006:doi
994:130
962:doi
918:doi
736:In
624:dBZ
542:RFD
496:In
416:dBZ
234:In
38:to
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1709:{{
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489:(
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
