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20:
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is near freezing at the surface. The strong convection that develops has enough moisture to produce whiteout conditions at places which line passes over as the wind causes intense blowing snow. This type of snow squall generally lasts less than 30 minutes at any point along its path but the motion of
941:
leading to deeper vertical growth and higher precipitable water levels increasing the volume of snow which can be produced by the squall. In cases where there is a large amount of vertical growth and mixing the squall may develop embedded cumulonimbus clouds resulting in lightning and thunder which
936:
instead of a higher level and must be at least −13 °F (−25 °C). The presence of surface moisture from bodies of water or preexisting liquid precipitation is also a significant contributing factor helping to raise the dew point temperature and saturate the boundary layer. This saturate can
931:
This is similar to a line of thunderstorms in the summer but the tops of the clouds are only 5,000 to 10,000 feet (1,500 to 3,000 m), often difficult to see on radar. Forecasting these types of events is equivalent to summer severe weather forecast for squall lines: presence of a sharp frontal
927:
lines which act similar to a traditional cold frontal passage. In situations where squalls develop post-frontally it is not unusual to have two or three linear squall bands pass in rapid succession only separated by 25 miles (40 km) with each passing the same point in roughly 30 minutes apart.
1002:, heavy amounts of snow can accumulate in short periods of time, possibly causing road closures and paralyzing cities. For instance, on January 9, 2015, a localized, heavy snow squall caused a 193-vehicle pile-up on I-94 highway near Galesburg, Michigan.
820:
difference between the water and 850 millibars (850 hPa) should be at least 23 °F (13 °C), surface temperature be around the freezing mark, the lake unfrozen, the path over the lake at least 100 kilometres (62 mi) and the directional
764:
clouds develop which cause heavy snow showers due to the large amount of moisture available. This occurs southwest of extratropical cyclones, with the curved cyclonic wind flow bringing cold air across the relatively warm
919:
the line can cover large distances. Frontal squalls may form a short distance ahead of the surface cold front or behind the cold front in situations where there are other contributing factors such as
825:
with height should be less than 30° from the surface to 850 millibars (850 hPa). Extremely cold air over still warm water in early winter can even produce
954:
1041:
600:
1337:
932:
trough with wind shift and low level jet of more than 30 knots (56 km/h; 35 mph). However, the cold dome behind the trough is at 850
938:
1063:
590:
647:
595:
689:
1139:
577:
873:
475:
1251:
863:
Radar image of a strong snow squall off Lake Huron in
December 2010. Over 150 cm of snow from this squall, fell north of
1276:
1082:
894:
995:
637:
1031:
642:
1332:
1307:
1036:
1312:
1143:
632:
1224:
501:
1112:
990:. The change in conditions is very sudden, with slippery conditions and abrupt loss of visibility due to
1116:
899:
682:
496:
254:
178:
19:
1172:
924:
920:
790:
735:
614:
212:
769:
which then leads to narrow lake-effect snow bands that can produce significant localized snowfall.
1058:
1046:
967:
660:
609:
506:
445:
271:
1151:
991:
770:
723:
281:
259:
166:
127:
816:) of snow per hour are common in these situations. In order for lake-effect snow to form, the
511:
958:
Rapidly deteriorating weather conditions during snow squalls often lead to traffic accidents.
999:
880:
857:
774:
755:
675:
389:
276:
188:
31:
864:
778:
582:
357:
60:
1199:
665:
572:
406:
773:
conditions will affect narrow corridors from shores to inland areas aligned along the
1326:
786:
528:
482:
428:
377:
264:
962:
1318:
Video of a snowsquall timelapse while driving on
Highway 407 ETR in Greater Toronto
715:
418:
342:
173:
845:
23:
A hybrid
Frontal-Lake Effect Snowsquall hitting Toronto, Canada during rush hour.
1016:
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911:
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817:
782:
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567:
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293:
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Environment Canada - Weather and
Meteorology - Hazardous weather-winter hazards
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90:
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557:
552:
347:
337:
249:
217:
200:
161:
139:
95:
851:
Radar trace of lake-effect snow squalls off the Great Lakes from US radars.
760:
When arctic air moves over large expanses of warmer open waters in winter,
987:
805:
727:
352:
1303:
975:
834:
518:
396:
384:
332:
315:
286:
244:
207:
154:
83:
39:
746:
There are two primary types of snow squalls: lake effect and frontal.
1252:"What are snow squalls and why they're more dangerous than blizzards"
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70:
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122:
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440:
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401:
327:
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direction. This will be enhanced when the moving air mass is
789:, however any body of water can produce them. Regions in
738:
and snow accumulations may or may not be significant.
923:
from a deepening low pressure system or a series of
781:by higher elevations. The name originates from the
16:
Sudden heavy snowfall accompanied with strong winds
974:Both types of snow squalls are very dangerous for
804:The areas affected by lake-effect snow are called
1250:Allison Chinchar, Meteorologist (18 Dec 2021).
683:
8:
906:A frontal snow squall is an intense frontal
1277:"Michigan I-94 Pileup | Firefighter Nation"
1042:Severe weather terminology (United States)
690:
676:
26:
879:A linear single banded snow squall over
1074:
38:
1134:
1132:
1225:"Snowstorm shuts down London Ontario"
939:convective available potential energy
937:significantly increase the amount of
7:
801:could experience such snow squalls.
1083:"National Weather Service Glossary"
1064:Severe weather terminology (Canada)
986:; even can be more dangerous than
898:Frontal snow squall moving toward
14:
1022:Warnings about lake-effect snow:
1204:Haby's Weather Forecasting Hints
1140:Meteorological Service of Canada
970:in Toronto due to a snow squall.
872:
856:
844:
659:
722:. It is often referred to as a
710:, is a sudden moderately heavy
829:, snow showers accompanied by
1:
1338:Snow or ice weather phenomena
808:and deposition rate of many
996:multiple-vehicle collisions
587:Severe weather terminology
49:Temperate and polar seasons
1354:
1206:. theweatherprediction.com
1173:"What is Lake-Effect Snow"
753:
718:and strong, gusty surface
1200:"Lake-effect forecasting"
1032:Lake Effect Snow Advisory
1308:National Weather Service
1304:Winter Weather Awareness
1037:Lake Effect Snow Warning
1231:. CBC. December 8, 2010
797:, such as the Canadian
971:
959:
903:
648:Tropical cyclone terms
24:
1142:(September 8, 2010).
1117:University of Wyoming
966:Winter conditions on
965:
957:
900:Boston, Massachusetts
897:
255:Extratropical cyclone
179:Air-mass thunderstorm
22:
994:, which often cause
730:but is localized in
726:and is similar to a
615:Weather modification
213:Anticyclonic tornado
1059:Snow Squall Warning
1047:Snow squall warning
968:Ontario Highway 401
910:line (similar to a
890:Frontal snow squall
610:Weather forecasting
446:Rain and snow mixed
272:Subtropical cyclone
1281:Firefighter Nation
1152:Environment Canada
1113:"Lake-Effect Snow"
1111:B. Geerts (1998).
972:
960:
904:
666:Weather portal
282:Atlantic hurricane
260:European windstorm
167:Volcanic lightning
128:Cumulonimbus cloud
25:
998:. In the case of
700:
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1289:
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1273:
1267:
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1247:
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1189:
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1162:
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1159:
1158:
1136:
1127:
1126:
1124:
1123:
1108:
1102:
1101:
1099:
1098:
1089:. Archived from
1079:
1000:lake-effect snow
881:Southern Ontario
876:
860:
848:
756:Lake-effect snow
750:Lake-effect snow
692:
685:
678:
664:
663:
277:Tropical cyclone
189:Dry thunderstorm
84:Tropical seasons
27:
1353:
1352:
1348:
1347:
1346:
1344:
1343:
1342:
1333:Weather hazards
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1171:Cameron Scott.
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1119:
1110:
1109:
1105:
1096:
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1076:
1072:
1008:
952:
921:dynamic lifting
902:, United States
892:
887:
886:
885:
884:
883:
877:
869:
868:
865:London, Ontario
861:
853:
852:
849:
775:prevailing wind
758:
752:
744:
696:
658:
653:
652:
628:
620:
619:
478:
468:
467:
380:
370:
369:
358:Ground blizzard
118:
108:
107:
86:
76:
75:
51:
17:
12:
11:
5:
1351:
1349:
1341:
1340:
1335:
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1324:
1321:
1320:
1315:
1310:
1299:
1298:External links
1296:
1294:
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1242:
1216:
1190:
1163:
1148:Winter Hazards
1128:
1103:
1073:
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891:
888:
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855:
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850:
843:
842:
841:
840:
839:
754:Main article:
751:
748:
743:
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698:
697:
695:
694:
687:
680:
672:
669:
668:
655:
654:
651:
650:
645:
640:
638:Climate change
635:
629:
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622:
621:
618:
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612:
607:
606:
605:
604:
603:
598:
593:
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573:Severe weather
570:
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407:Megacryometeor
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1179:. RR Donnelly
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1174:
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1164:
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1093:on 2006-10-09
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1038:
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1026:United States
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993:
989:
985:
981:
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940:
935:
929:
926:
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917:
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859:
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838:
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832:
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787:North America
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686:
681:
679:
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657:
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649:
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643:Tornado terms
641:
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623:
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613:
611:
608:
602:
601:United States
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483:Air pollution
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383:
382:
379:
378:Precipitation
374:
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349:
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138:
134:
131:
129:
126:
125:
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121:
120:
117:
112:
111:
104:
101:
97:
94:
93:
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89:
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80:
79:
72:
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64:
62:
59:
57:
54:
53:
50:
45:
44:
41:
37:
33:
29:
28:
21:
1285:. Retrieved
1280:
1271:
1259:. Retrieved
1255:
1245:
1235:December 13,
1233:. Retrieved
1228:
1219:
1208:. Retrieved
1203:
1193:
1181:. Retrieved
1177:Science 360!
1176:
1166:
1155:. Retrieved
1147:
1120:. Retrieved
1106:
1095:. Retrieved
1091:the original
1087:crh.noaa.gov
1086:
1077:
1021:
982:, and other
973:
930:
905:
803:
759:
745:
716:blowing snow
707:
703:
701:
419:Diamond dust
362:
343:Winter storm
174:Thunderstorm
1198:Jeff Haby.
1183:October 23,
1017:Snow shower
944:thundersnow
916:temperature
912:squall line
827:thundersnow
818:temperature
814:centimetres
783:Great Lakes
767:Great Lakes
704:snow squall
633:Meteorology
568:Meteorology
456:Snow roller
451:Snow grains
414:Ice pellets
363:Snow squall
294:Storm surge
240:Anticyclone
196:Mesocyclone
184:Thundersnow
133:Arcus cloud
1327:Categories
1306:by the US
1287:2015-10-09
1283:. May 2015
1210:2009-08-12
1157:2010-10-04
1122:2008-12-24
1097:2024-03-12
1070:References
1012:Convection
942:is dubbed
908:convective
823:wind shear
762:convective
708:snowsquall
627:Glossaries
563:Jet stream
502:Convection
488:Atmosphere
436:Cloudburst
299:Dust storm
265:Nor'easter
235:Fire whirl
230:Dust devil
223:Waterspout
150:Heat burst
145:Microburst
103:Wet season
91:Dry season
992:whiteouts
988:blizzards
984:travelers
980:airplanes
976:motorists
831:lightning
806:snowbelts
799:Maritimes
558:Heat wave
553:Cold wave
497:Chemistry
348:Ice storm
338:Firestorm
250:Polar low
218:Landspout
201:Supercell
162:Lightning
140:Downburst
96:Harmattan
30:Part of
1229:CBC News
1006:See also
914:), when
785:area of
779:uplifted
771:Whiteout
736:location
728:blizzard
724:whiteout
712:snowfall
429:Freezing
390:Freezing
353:Blizzard
32:a series
950:Dangers
835:thunder
583:Extreme
529:Physics
519:Climate
507:Physics
397:Graupel
385:Drizzle
333:Sirocco
316:Monsoon
287:Typhoon
245:Cyclone
208:Tornado
155:Derecho
40:Weather
1261:19 Feb
1144:"Snow"
1053:Canada
925:trough
810:inches
795:oceans
734:or in
591:Canada
546:Season
476:Topics
321:Amihan
309:Haboob
304:Simoom
116:Storms
71:Autumn
66:Summer
61:Spring
56:Winter
742:Types
720:winds
714:with
706:, or
596:Japan
524:Cloud
512:River
461:Slush
123:Cloud
1263:2022
1237:2017
1185:2013
934:mbar
833:and
732:time
578:List
541:Mist
441:Snow
424:Rain
402:Hail
328:Gale
1256:CNN
793:of
791:lee
536:Fog
1329::
1279:.
1254:.
1227:.
1202:.
1175:.
1150:.
1146:.
1131:^
1115:.
1085:.
978:,
946:.
837:.
702:A
34:on
1290:.
1265:.
1239:.
1213:.
1187:.
1160:.
1125:.
1100:.
867:.
812:(
691:e
684:t
677:v
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
