141:
654:, or moisture, gradient. Near the surface, warm moist air that is denser than warmer, dryer air wedges under the drier air in a manner similar to that of a cold front wedging under warmer air. When the warm moist air wedged under the drier mass heats up, it becomes less dense and rises and sometimes forms thunderstorms. At higher altitudes, the warm moist air is less dense than the cooler, drier air and the boundary slope reverses. In the vicinity of the reversal aloft, severe weather is possible, especially when a triple point is formed with a cold front.
366:, rotate outward at the surface and clockwise in the northern hemisphere as opposed to outward and counterclockwise in the southern hemisphere. Under surface highs, sinking of the atmosphere slightly warms the air by compression, leading to clearer skies, winds that are lighter, and a reduced chance of precipitation. The descending air is dry, hence less energy is required to raise its temperature. If high pressure persists, air pollution will build up due to pollutants trapped near the surface caused by the subsiding motion associated with the high.
605:
isotherms. A wide variety of weather can be found along a stationary front, characterized more by its prolonged presence than by a specific type. Stationary fronts may dissipate after several days, but can change into a cold or warm front if conditions aloft change, driving one air mass toward the other. Stationary fronts are marked on weather maps with alternating red half-circles and blue spikes pointing in opposite directions, indicating no significant movement.
564:
186:
381:
556:
overtaking the warm front is cooler than the cool air ahead of the warm front, and plows under both air masses. In a warm occlusion, the air mass overtaking the warm front is not as cool as the cold air ahead of the warm front, and rides over the colder air mass while lifting the warm air. Occluded fronts are indicated on a weather map by a purple line with alternating half-circles and triangles pointing in direction of travel.
704:
667:
515:
243:
691:. The convection then moves east and equatorward into the warm sector, parallel to low-level thickness lines. When the convection is strong and linear or curved, the MCS is called a squall line, with the feature placed at the leading edge where the significant wind shifts and pressure rises. Even weaker and less organized areas of thunderstorms will lead to locally cooler air and higher pressures, and
31:
313:
658:
the focus of afternoon and evening thunderstorms. A dry line is depicted on United States surface analyses as a brown line with scallops, or bumps, facing into the moist sector. Dry lines are one of the few surface fronts where the special shapes along the drawn boundary do not necessarily reflect the boundary's direction of motion.
657:
During daylight hours, drier air from aloft drifts down to the surface, causing an apparent movement of the dryline eastward. At night, the boundary reverts to the west as there is no longer any solar heating to help mix the lower atmosphere. If enough moisture converges upon the dryline, it can be
467:
since cold air is denser than warm air and rapidly lifts as well as pushes the warmer air. Cold fronts are typically accompanied by a narrow band of clouds, showers and thunderstorms. On a weather map, the surface position of the cold front is marked with a blue line of triangles (pips) pointing in
320:
Centers of surface high- and low-pressure areas that are found within closed isobars on a surface weather analysis are the absolute maxima and minima in the pressure field, and can tell a user in a glance what the general weather is in their vicinity. Weather maps in
English-speaking countries will
273:
points in the direction from which the wind is coming. Each full flag on the wind barb represents 10 knots (19 km/h) of wind, each half flag represents 5 knots (9 km/h). When winds reach 50 knots (93 km/h), a filled in triangle is used for each 50 knots (93 km/h) of wind. In the
559:
Occluded fronts usually form around low pressure systems in the mature or late stages of their life cycle, but some continue to deepen after occlusion, and some do not form occluded fronts at all. The weather associated with an occluded front includes a variety of cloud and precipitation patterns,
726:
During the afternoon, air pressure decreases over the land as the warmer air rises. The relatively cooler air over the sea rushes in to replace it. The result is a relatively cool onshore wind. This process usually reverses at night where the water temperature is higher relative to the landmass,
604:
A stationary front is a non-moving boundary between two different air masses. They tend to remain in the same area for long periods of time, sometimes undulating in waves. Often a less-steep temperature gradient continues behind (on the cool side of) the sharp frontal zone with more widely spaced
485:
mark the position on the Earth's surface where a relatively warm body of air is advancing into colder air. The front is marked on the warm edge of the gradient in isotherms, and lies within a low pressure trough that tends to be broader and weaker than that of a cold front. Warm fronts move more
349:
can form over relatively mild ocean waters when cold air sweeps in from the ice cap. The relatively warmer water leads to upward convection, causing a low to form, and precipitation usually in the form of snow. Tropical cyclones and winter storms are intense varieties of low pressure. Over land,
555:
Occluded fronts are indicated on a weather map by a purple line with alternating half-circles and triangles pointing in direction of travel: that is, with a mixture of warm and cold frontal colors and symbols. Occlusions can be divided into warm vs. cold types. In a cold occlusion, the air mass
205:
completed their process of automated surface plotting by 1987. By 1999, computer systems and software had finally become sophisticated enough to allow for the ability to underlay on the same workstation satellite imagery, radar imagery, and model-derived fields such as atmospheric thickness and
156:
network by 1845 made it possible to gather weather information from multiple distant locations quickly enough to preserve its value for real-time applications. The
Smithsonian Institution developed its network of observers over much of the central and eastern United States between the 1840s and
227:
have made it possible to devise finely tailored weather maps. Weather information can quickly be matched to relevant geographical detail. For instance, icing conditions can be mapped onto the road network. This will likely continue to lead to changes in the way surface analyses are created and
169:
finally established standard time. Other countries followed the lead of the United States in taking simultaneous weather observations, starting in 1873. Other countries then began preparing surface analyses. The use of frontal zones on weather maps did not appear until the introduction of the
164:
The weather data was at first less useful as a result of the different times at which weather observations were made. The first attempts at time standardization took hold in Great
Britain by 1855. The entire United States did not finally come under the influence of time zones until 1905, when
486:
slowly than cold fronts because cold air is denser, and is only pushed along (not lifted from) the Earth's surface. The warm air mass overrides the cold air mass, so temperature and cloud changes occur at higher altitudes before those at the surface. Clouds ahead of the warm front are mostly
126:, which frequently accompanies precipitation. Various symbols are used not just for frontal zones and other surface boundaries on weather maps, but also to depict the present weather at various locations on the weather map. Areas of precipitation help determine the frontal type and location.
734:
If enough moisture exists, thunderstorms can form along sea breeze fronts that then can send out outflow boundaries. This causes chaotic wind/pressure regimes if the steering flow is weak. Like all other surface features, sea breeze fronts lie inside troughs of low pressure.
722:
of water is so high, there is little diurnal temperature change in bodies of water, even on the sunniest days. The water temperature varies less than 1 °C (1.8 °F). By contrast, the land, with a lower specific heat, can vary several degrees in a matter of hours.
218:
workstations. By 2001, the various surface analyses done within the
National Weather Service were combined into the Unified Surface Analysis, which is issued every six hours and combines the analyses of four different centers. Recent advances in both the fields of
608:
As airmass temperatures equalize, stationary fronts may become smaller in scale, degenerating to a narrow zone where wind direction changes over a short distance, known as a shear line, depicted as a blue line of single alternating dots and dashes.
717:
fronts occur on sunny days when the landmass warms the air above it to a temperature above the water temperature. Similar boundaries form downwind on lakes and rivers during the day, as well as offshore landmasses at night. Since the
408:
is very large. When a front passes over a point, it is marked by changes in temperature, moisture, wind speed and direction, a minimum of atmospheric pressure, and a change in the cloud pattern, sometimes with precipitation.
682:
Organized areas of thunderstorm activity not only reinforce pre-existing frontal zones, but they can outrun cold fronts. This outrunning occurs in a pattern where the upper level jet splits into two streams. The resultant
345:. Weather is normally unsettled in the vicinity of a cyclone, with increased cloudiness, increased winds, increased temperatures, and upward motion in the atmosphere, which leads to an increased chance of precipitation.
506:
can precede a warm front when precipitation falls into areas of colder air, but increasing surface temperatures and wind tend to dissipate it after a warm front passes through. Cases with environmental
727:
leading to an offshore land breeze. However, if water temperatures are colder than the land at night, the sea breeze may continue, only somewhat abated. This is typically the case along the
304:
A synoptic scale feature is one whose dimensions are large in scale, more than several hundred kilometers in length. Migratory pressure systems and frontal zones exist on this scale.
511:
can be conducive to thunderstorm development. On weather maps, the surface location of a warm front is marked with a red line of half circles pointing in the direction of travel.
261:, atmospheric pressure, pressure tendency, and ongoing weather are plotted. The circle in the middle represents cloud cover; fraction it is filled in represents the degree of
95:
became the first organization to draw real-time surface analyses. Use of surface analyses began first in the United States, spreading worldwide during the 1870s. Use of the
695:
exist ahead of this type of activity, "SQLN" or "SQUALL LINE", while outflow boundaries are depicted as troughs with a label of "OUTFLOW BOUNDARY" or "OUTFLOW BNDRY".
197:
model just after World War I, the United States did not formally analyze fronts on surface analyses until late 1942, when the WBAN Analysis Center opened in downtown
152:
The use of weather charts in a modern sense began in the middle portion of the 19th century in order to devise a theory on storm systems. The development of a
1440:
1509:
1357:
1580:
1193:
441:) as airflow wraps around a low pressure center. Frontal zones can be distorted by such geographic features as mountains and large bodies of water.
174:
in the late 1910s, despite Loomis' earlier attempt at a similar notion in 1841. Since the leading edge of air mass changes bore resemblance to the
1122:
210:
in combination with surface observations to make for the best possible surface analysis. In the United States, this development was achieved when
1103:
540:
is that they are formed when a cold front overtakes a warm front. A more modern view suggests that they form directly during the wrap-up of the
215:
1456:
631:
253:
When analyzing a weather map, a station model is plotted at each point of observation. Within the station model, the temperature, dewpoint,
83:
The first weather maps in the 19th century were drawn well after the fact to help devise a theory on storm systems. After the advent of the
1533:
1422:
490:
with precipitation that increases gradually as the front approaches. Ahead of a warm front, descending cloud bases will often begin with
794:
2019:
290:(lines of equal wind speed) are drawn. The abstract weather symbols were devised to take up the least room possible on weather maps.
978:
1050:
560:
including dry slots and banded precipitation. Cold, warm and occluded fronts often meet at the point of occlusion or triple point.
1325:
1151:
1573:
1543:
1722:
1405:
994:
945:
876:
1069:
634:
systems like thunderstorms. Horizontal dimensions generally range from over ten kilometres to several hundred kilometres.
135:
321:
depict their highs as Hs and lows as Ls, while
Spanish-speaking countries will depict their highs as As and lows as Bs.
1489:
161:
inherited this network between 1870 and 1874 by an act of
Congress, and expanded it to the west coast soon afterwards.
99:
for frontal analysis began in the late 1910s across Europe, with its use finally spreading to the United States during
1742:
1566:
437:. Fronts usually travel from west to east, although they can move in a north-south direction or even east to west (a
286:(lines of equal pressure), isallobars (lines of equal pressure change), isotherms (lines of equal temperature), and
1890:
1033:
1298:
1273:
201:
The effort to automate map plotting began in the United States in 1969, with the process complete in the 1970s.
1937:
53:
elements over a geographical area at a specified time based on information from ground-based weather stations.
333:, are located in minima in the pressure field. Rotation is inward at the surface and counterclockwise in the
1769:
1737:
1684:
1506:
1354:
224:
140:
755:
1190:
1177:
2024:
1998:
962:
684:
646:
is the boundary between dry and moist air masses east of mountain ranges with similar orientation to the
107:
88:
687:(MCS) forms at the point of the upper level split in the wind pattern at the area of the best low-level
1932:
1689:
1553:
1119:
299:
1099:
1912:
1846:
1674:
549:
422:
1779:
1473:
1453:
1341:
1210:
998:
1164:
905:
1980:
1902:
773:
765:
456:
171:
96:
92:
429:
is a sharpening of the general equator-to-pole temperature gradient, underlying a high-altitude
1834:
1794:
1747:
1732:
1714:
1426:
810:
744:
508:
384:
Occluded cyclone example. The triple point is the intersection of the cold, warm, and occluded
158:
145:
846:
1881:
1774:
1764:
1727:
800:
623:
618:
35:
1374:
1020:
463:. Cold fronts can move up to twice as quickly as warm fronts and produce sharper changes in
1960:
1927:
1829:
1824:
1789:
1538:
1285:
1236:
1086:
688:
460:
283:
1139:
56:
Weather maps are created by plotting or tracing the values of relevant quantities such as
8:
1922:
1907:
975:
815:
438:
338:
334:
1528:
1289:
1240:
1046:
502:(mid-level) clouds, and eventually lower in the atmosphere as the front passes through.
1694:
1321:
919:
495:
421:
is not moving. Fronts classically wrap around low pressure centers as indicated in the
115:
57:
106:
Surface weather analyses have special symbols that show frontal systems, cloud cover,
1975:
1871:
1759:
1601:
1303:
1254:
949:
499:
1558:
933:
34:
A surface weather analysis for the United States on
October 21, 2006. By that time,
1293:
1244:
692:
599:
418:
198:
69:
1402:
872:
455:
A cold front is located at the leading edge of a sharp temperature gradient on an
1626:
1513:
1493:
1460:
1409:
1361:
1329:
1197:
1126:
1107:
1073:
1066:
1054:
982:
880:
647:
20:
1225:"Occluded Fronts and the Occlusion Process: A Fresh Look at Conventional Wisdom"
834:
Air
Apparent: How Meteorologists Learned to Map, Predict, and Dramatize Weather.
1917:
892:
781:
627:
568:
537:
531:
342:
258:
175:
77:
73:
1548:
1387:
Mesoscale classifications: their history and their application to forecasting.
859:
2013:
1699:
1307:
1258:
777:
769:
719:
487:
385:
375:
265:. Outside the United States, temperature and dewpoint are plotted in degrees
246:
237:
207:
1486:
1876:
1851:
1784:
1661:
1249:
1224:
545:
491:
434:
123:
100:
425:
here depicted for the northern hemisphere. On a larger scale, the Earth's
274:
United States, rainfall plotted in the corner of the station model are in
1965:
1804:
1704:
805:
761:
671:
541:
426:
363:
351:
220:
179:
91:
became possible for the first time, and beginning in the late 1840s, the
65:
61:
46:
1970:
1942:
1856:
1651:
1636:
1616:
728:
714:
708:
519:
482:
477:
450:
430:
414:
410:
279:
254:
211:
1272:
Stoelinga, Mark T.; Locatelli, John D.; Hobbs, Peter V. (2002-05-01).
666:
185:
1812:
1641:
1621:
1606:
651:
563:
468:
the direction of travel, at the leading edge of the cooler air mass.
346:
270:
202:
153:
84:
24:
1990:
1952:
1866:
1611:
1274:"Warm Occlusions, Cold Occlusions, and Forward-Tilting Cold Fronts"
1032:
Saseendran S. A., Harenduprakash L., Rathore L. S. and Singh S. V.
643:
405:
397:
393:
380:
262:
30:
282:. Once a map has a field of station models plotted, the analyzing
1861:
999:
Hydrometeorological
Prediction Center 1999 Accomplishment Report.
703:
464:
400:. Strictly speaking, the front is marked at the warmer edge of a
330:
287:
266:
194:
166:
50:
963:
Prospectus for an NMC Digital
Facsimile Incoder Mapping Program.
242:
1441:
A Numerical Simulation of Dryline Sensitivity to Soil Moisture.
976:
The Hong Kong Observatory Computer System and Its Applications.
675:
514:
278:. The international standard rainfall measurement unit is the
1669:
950:
A Brief History of the Hydrometeorological Prediction Center.
768:, characterized by a localized, small-scale area of enhanced
312:
1646:
1299:
10.1175/1520-0477(2002)083<0709:WOCOAF>2.3.CO;2
923:, 2003, revised, 2004, 2006, p. 5. Retrieved on 2006-07-14.
275:
182:, the term "front" came into use to represent these lines.
1679:
503:
1271:
1034:
A GIS application for weather analysis and forecasting.
118:, implying clear skies and relatively warm weather. An
19:"Surface analysis" redirects here. For other uses, see
920:
Perspectives on Fred Sanders's Research on Cold Fronts
661:
1588:
231:
1320:National Weather Service Office, Norman, Oklahoma.
1087:
Selected DataStreme Atmosphere Weather Map Symbols.
1019:David Roth. Hydrometeorological Prediction Center.
593:
459:analysis, often marked by a sharp surface pressure
1485:Office of the Federal Coordinator for Meteorology.
1392:American Meteorological Society, Boston, p. 18–35.
1223:Schultz, David M.; Vaughan, Geraint (2011-04-01).
396:that have different density, air temperature, and
110:, or other important information. For example, an
354:are indicative of hot weather during the summer.
2011:
871:Frank Rives Millikan. Smithsonian Institution.
707:Idealized circulation pattern associated with a
1278:Bulletin of the American Meteorological Society
1229:Bulletin of the American Meteorological Society
749:
1222:
413:develop where the cold air mass is advancing,
129:
1574:
698:
392:Fronts in meteorology are boundaries between
1723:Convective available potential energy (CAPE)
873:Joseph Henry: Father of the Weather Service.
189:Present weather symbols used on weather maps
38:was active (Paul later became a hurricane).
1581:
1567:
1140:Weather's Highs and Lows: Part 1 The High.
760:A descending reflectivity core (DRC) is a
337:as opposed to inward and clockwise in the
293:
193:Despite the introduction of the Norwegian
1499:
1297:
1248:
836:University of Chicago PressChicago: 1999.
1152:Meteorología del aeropuerto de La Palma.
702:
665:
562:
513:
379:
311:
241:
184:
139:
29:
795:Bowditch's American Practical Navigator
417:where the warm air is advancing, and a
228:displayed over the next several years.
2012:
1390:Mesoscale Meteorology and Forecasting.
738:
674:such as this one can be a sign that a
650:, depicted at the leading edge of the
1562:
1539:Unified Surface Analysis Manual — NWS
1015:
1013:
1011:
1009:
1007:
995:Hydrometeorological Prediction Center
946:Hydrometeorological Prediction Center
839:
630:systems like fronts, but larger than
612:
362:High-pressure systems, also known as
329:Low-pressure systems, also known as
1685:Convective condensation level (CCL)
1191:Pressure, Wind and Weather Systems.
662:Outflow boundaries and squall lines
571:that may be found on a weather map:
307:
249:plotted on surface weather analyses
136:History of surface weather analysis
122:, on the other hand, may represent
13:
1891:Equivalent potential temperature (
1100:INTRODUCTION TO DRAWING ISOPLETHS.
1004:
232:Station model used on weather maps
14:
2036:
1743:Conditional symmetric instability
1589:Meteorological data and variables
1522:
1150:Agencia Estatal de Meteorología.
1085:American Meteorological Society.
847:American Pioneers in Meteorology.
552:and rotation around the cyclone.
525:
518:Illustration clouds overriding a
2020:Synoptic meteorology and weather
1690:Lifting condensation level (LCL)
1021:Unified Surface Analysis Manual.
594:Stationary fronts and shearlines
357:
214:workstations were replaced by n-
1675:Cloud condensation nuclei (CCN)
1479:
1466:
1446:
1433:
1415:
1395:
1379:
1367:
1347:
1334:
1314:
1265:
1216:
1203:
1183:
1170:
1157:
1144:
1132:
1112:
1092:
1079:
1059:
1039:
1026:
988:
968:
955:
324:
1938:Wet-bulb potential temperature
1780:Level of free convection (LFC)
1544:Unified Surface Analysis — NWS
1474:Dry Line: A Moisture Boundary.
1189:United Kingdom School System.
1165:Weather Basics - Low Pressure.
939:
926:
911:
898:
885:
865:
852:
827:
225:geographic information systems
1:
1981:Pressure-gradient force (PGF)
1903:Sea surface temperature (SST)
1738:Convective momentum transport
1534:Norwegian Cyclone Model — NWS
821:
471:
444:
1795:Bulk Richardson number (BRN)
934:Air Masses and Weather Maps.
756:Descending reflectivity core
750:Descending reflectivity core
89:surface weather observations
7:
1999:Maximum potential intensity
1765:Free convective layer (FCL)
1728:Convective inhibition (CIN)
787:
685:mesoscale convective system
637:
567:A guide to the symbols for
548:, and lengthen due to flow
130:History of surface analysis
10:
2041:
1933:Wet-bulb globe temperature
1790:Maximum parcel level (MPL)
1529:"The Mid-Latitude Cyclone"
1045:National Weather Service.
895:. Retrieved on 2007-06-24.
753:
742:
699:Sea and land breeze fronts
626:features are smaller than
616:
597:
529:
475:
448:
373:
300:Synoptic scale meteorology
297:
235:
133:
18:
1989:
1951:
1913:Thermodynamic temperature
1847:Forest fire weather index
1803:
1713:
1660:
1594:
1505:Glossary of Meteorology.
1452:Glossary of Meteorology.
1353:Glossary of Meteorology.
1324:Retrieved on 2006-10-22.
1118:Glossary of meteorology.
1102:Retrieved on 2007-04-29.
1053:October 25, 2007, at the
1049:Retrieved on 2007-04-29.
879:October 20, 2006, at the
875:Retrieved on 2006-10-22.
536:The classical view of an
369:
1835:Equivalent temperature (
1748:Convective temperature (
1632:Surface weather analysis
1516:Retrieved on 2006-10-22.
1496:Retrieved on 2006-10-22.
1476:Retrieved on 2006-10-22.
1472:University of Illinois.
1463:Retrieved on 2006-10-22.
1443:Retrieved on 2007-05-10.
1412:Retrieved on 2006-12-05.
1376:Retrieved on 2021-03-13.
1364:Retrieved on 2006-10-22.
1344:Retrieved on 2006-10-22.
1340:University of Illinois.
1328:October 9, 2006, at the
1213:Retrieved on 2006-10-22.
1209:University of Illinois.
1200:Retrieved on 2007-05-05.
1180:Retrieved on 2007-05-05.
1167:Retrieved on 2007-05-05.
1129:Retrieved on 2007-05-10.
1089:Retrieved on 2007-05-10.
1076:Retrieved on 2007-05-10.
1065:Dr Elizabeth R. Tuttle.
1036:Retrieved on 2007-05-05.
1023:Retrieved on 2006-10-22.
1001:Retrieved on 2007-05-05.
985:Retrieved on 2007-05-05.
965:Retrieved on 2007-05-05.
952:Retrieved on 2007-05-05.
936:Retrieved on 2006-10-22.
908:Retrieved on 2007-05-05.
862:Retrieved on 2007-04-18.
849:Retrieved on 2007-04-18.
316:Wind barb interpretation
49:that provides a view of
43:Surface weather analysis
1882:Potential temperature (
1627:Surface solar radiation
1549:Glossary of Meteorology
1487:Chapter 2: Definitions.
1106:April 28, 2007, at the
974:Hong Kong Observatory.
932:Bureau of Meteorology.
766:supercell thunderstorms
764:phenomenon observed in
294:Synoptic scale features
172:Norwegian cyclone model
97:Norwegian cyclone model
93:Smithsonian Institution
1872:Relative humidity (RH)
1760:Equilibrium level (EL)
1733:Convective instability
1403:Dryline cross section.
1250:10.1175/2010BAMS3057.1
1047:Station Model Example.
906:An Expanding Presence.
811:Outline of meteorology
745:Microscale meteorology
711:
679:
590:
522:
389:
317:
250:
190:
159:U.S. Army Signal Corps
149:
146:Great Blizzard of 1888
39:
1429:on 27 September 2007.
1385:Fujita, T. T., 1986.
801:Extratropical cyclone
706:
669:
619:Mesoscale meteorology
566:
517:
383:
315:
245:
188:
143:
45:is a special type of
33:
1961:Atmospheric pressure
1928:Wet-bulb temperature
1830:Dry-bulb temperature
1825:Dew point depression
893:Daylight Saving Time
731:coast, for example.
435:thermal wind balance
148:on March 12 at 10 pm
144:Surface analysis of
1923:Virtual temperature
1908:Temperature anomaly
1602:Adiabatic processes
1290:2002BAMS...83..709S
1241:2011BAMS...92..443S
858:Human Intelligence.
816:Ridge (meteorology)
739:Microscale features
577:3. stationary front
498:(high-level), then
339:southern hemisphere
335:northern hemisphere
36:Tropical Storm Paul
16:Type of weather map
2025:Weather prediction
1695:Precipitable water
1512:2007-03-14 at the
1492:2009-05-06 at the
1459:2011-09-19 at the
1408:2008-01-20 at the
1373:Aviation Weather.
1360:2007-03-14 at the
1196:2007-09-27 at the
1125:2007-08-11 at the
1072:2008-07-09 at the
981:2006-12-31 at the
917:David M. Schultz.
770:radar reflectivity
712:
693:outflow boundaries
680:
613:Mesoscale features
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58:sea level pressure
40:
2007:
2006:
1976:Pressure gradient
1785:Lifted index (LI)
1439:Lewis D. Grasso.
1342:Stationary Front.
581:5. surface trough
579:4. occluded front
76:features such as
2032:
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845:Eric R. Miller.
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600:Stationary front
587:8. tropical wave
439:"backdoor" front
419:stationary front
308:Pressure centers
199:Washington, D.C.
70:geographical map
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1211:Occluded Front.
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860:Francis Galton.
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534:
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447:
433:for reasons of
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176:military fronts
138:
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87:, simultaneous
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21:surface science
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1523:External links
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762:meteorological
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583:6. squall line
569:weather fronts
538:occluded front
532:Occluded front
530:Main article:
527:
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343:Coriolis force
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114:may represent
78:weather fronts
74:synoptic scale
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1067:Weather Maps.
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573:1. cold front
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247:Station model
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238:Station model
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116:high pressure
113:
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108:precipitation
104:
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72:to help find
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1877:Mixing ratio
1852:Haines Index
1836:
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1662:Condensation
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1427:the original
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546:cyclogenesis
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496:cirrostratus
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402:frontal zone
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391:
364:anticyclones
361:
352:thermal lows
328:
325:Low pressure
319:
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163:
151:
124:low pressure
119:
111:
105:
101:World War II
82:
55:
42:
41:
1966:Baroclinity
1813:Dew point (
1805:Temperature
1705:Water vapor
1507:Sea Breeze.
1454:Lee Trough.
1423:"Lecture 3"
1355:Shear Line.
806:Frontolysis
678:is imminent
672:shelf cloud
632:storm-scale
585:7. dry line
550:deformation
509:instability
500:altostratus
483:Warm fronts
427:polar front
415:warm fronts
411:Cold fronts
341:due to the
221:meteorology
180:World War I
157:1860s. The
66:cloud cover
62:temperature
47:weather map
2014:Categories
1943:Wind chill
1857:Heat index
1715:Convection
1652:Wind shear
1637:Visibility
1617:Lapse rate
1098:CoCoRAHS.
822:References
743:See also:
729:California
715:Sea breeze
709:sea breeze
617:See also:
520:warm front
488:stratiform
478:Warm front
472:Warm front
451:Cold front
445:Cold front
431:jet stream
404:where the
394:air masses
347:Polar lows
298:See also:
280:millimeter
255:wind speed
236:See also:
212:Intergraph
134:See also:
1642:Vorticity
1622:Lightning
1607:Advection
1308:0003-0007
1259:0003-0007
780:into the
776:from the
652:dew point
624:Mesoscale
589:9. Trowal
271:wind barb
259:direction
203:Hong Kong
154:telegraph
85:telegraph
25:etymology
1991:Velocity
1953:Pressure
1867:Humidity
1770:Helicity
1612:Buoyancy
1510:Archived
1490:Archived
1457:Archived
1406:Archived
1358:Archived
1326:Archived
1194:Archived
1123:Archived
1104:Archived
1070:Archived
1051:Archived
979:Archived
877:Archived
788:See also
774:descends
644:dry line
638:Dry line
457:isotherm
406:gradient
398:humidity
331:cyclones
288:isotachs
263:overcast
1862:Humidex
1775:K Index
1595:General
1286:Bibcode
1237:Bibcode
648:Rockies
544:during
465:weather
284:isobars
267:Celsius
195:cyclone
167:Detroit
68:onto a
51:weather
1306:
1257:
961:ESSA.
904:NOAA.
689:inflow
676:squall
492:cirrus
461:trough
386:fronts
370:Fronts
276:inches
269:. The
64:, and
1670:Cloud
772:that
423:image
216:AWIPS
1647:Wind
1304:ISSN
1255:ISSN
642:The
494:and
257:and
223:and
23:and
1680:Fog
1294:doi
1245:doi
504:Fog
178:of
2016::
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1893:θ
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120:L
112:H
27:.
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