A major low pressure system coming in from Lake Michigan caused

A major low pressure system coming in from Lake Michigan caused

Winds of December 18–19, 2000
Summary of Storm Event
December 21, 2000
Series on Extreme Weather in Quebec
CES-Q99-02
Perrier R. and M. Slivitzky (1999), Overview of Heavy Rainfall
events in
Quebec, Scientific Report, in collaboration with
Environment Canada, Quebec Region, 48 pp.
CES-Q99-01
Milton J. and A. Bourque (1999), A Climatological Account of the
January 1998 Ice Storm in Quebec, 2nd edition, Atmospheric
Sciences and Environmental Issues, Environment Canada, Quebec
Region, 87 pp.
CES-Q98-01
Milton J. and A. Bourque (1998), A Climatological Account of the
January 1998 Ice Storm in Quebec, 2nd edition, Atmospheric
Sciences and Environmental Issues, Environment Canada, Quebec
Region, 87 pp.
Other reports/studies on extreme weather in Quebec
ENVIRONMENT CANADA (1998), Characterization of Rainfalls of November 7-10, 1996,
over southern Quebec, Scientific Services Division, Quebec Region,
69 pp.
ENVIRONMENT CANADA (1997), Torrential rains of July 18 to 21 1996, in the province
of Quebec: Analysis and interpretation of meteorological and
climatological data, Scientific Services Division, Quebec Region,
September 9, 1997, 103 pp.
ENVIRONMENT CANADA (1987), Les pluies du 14 juillet 1987 dans la région de
Montréal/July 14th 1987 rainstorm in the Montreal area, Expert
Report, Environment Canada, Scientific Services Division, 52 pp.
For more information:
Centre de Ressources en Impacts et Adaptation
au Climat et à ses Changements - CRIACC
Place Bonaventure, Portail Nord-Est,
800, rue de la Gauchetière Ouest, suite 7810
Montréal (Québec), Canada
H5A 1L9
E-mail : [email protected]
Internet address: www.criacc.qc.ca
Aussi disponible en français
A strong low-pressure system from Lake Michigan produced severe winds as it swept across
Quebec on December 18–19, 2000. At 00:00 GMT on Sunday evening, the center of the low
was measured at 984 mb near Mont-Laurier. At 12:00 GMT on Monday, December 18, it
was located northwest of Baie-Comeau at 962 mb; it then started filling and, by evening, was
located over Labrador. The system underwent a maximum deepening of close to 22 mb in
12 hours as it moved into the province (Figures 1–7).
The temperature gradients supporting this system were substantial. Surface temperatures
reached up to 8–15°C in the warm sector of the low, but dropped rapidly to below freezing
after the passage of the arctic cold front. A dome of cold air (approximately -10°C to -20°C)
was present behind the low.
In terms of precipitation, heavy snow was observed east of the system, especially on the
North Shore. It was caused mainly by strong upslope easterly winds over the region.
Furthermore, as in typical winter lows over southern Quebec, a few hours of freezing
precipitation preceded the influx of warm air within the system. In the warm sector, several
regions also reported heavy rain. A total of 20 to 50 mm of liquid precipitation (mainly nonfreezing) fell with this system. The precipitation turned to snow after the passage of the cold
front, causing heavy snow accumulations to the northwest of the low’s path.
Wind strength was the exceptional weather parameter of the winter storm. Despite easterly
gusts of 25–45 km/h observed ahead of the system along the St. Lawrence River and in the
Saguenay region, the strength of the system was defined by the winds behind the low
(Table 1). Most stations located along the St. Lawrence River recorded average wind speeds
of between 40 and 60 km/h on December 18, with maximum gusts of over 90 km/h. In the
Saguenay region, all stations in the observation network measured gusts of 100 km/h or over,
with Pointe-Claveau recording a maximum wind gust of 125 km/h on December 18.
Figure 1: Objective analysis of 18/12/2000, 00:00 GMT Figure 2: Objective analysis of 18/12/2000, 06:00 GMT
December 21, 2000
1
Figure 3: Objective analysis of 18/12/2000, 12:00 GMT Figure 4: Objective analysis of 18/12/2000, 18:00 GMT
Figure 5: Objective analysis of 19/12/2000, 00:00 GMT Figure 6: Objective analysis of 19/12/2000, 06:00 GMT
Figure 7: Objective analysis of 19/12/2000, 12:00 GMT
December 21, 2000
2
Table 1: Maximum wind gusts for December 18–19, 2000, and records for the month of
December (preliminary data)
Maximum wind gust
record–December
Maximum wind gust
December 18-19, 2000
New
wind gust
records for
December
Climate ID
Identifier
Station
Data
recording
period
Wind gust speed
(km/hr)
Day
Wind gust speed
(km/hr)
Year
Day
1955 1955 1980 1955 1962 1955 1955 1957 1955 1977 1965 1955 -
107
91
57
54
80
96
113
100
100
89
93
72
18
18
18
18
18
18
18
18
18
18
18
18
103
113
69
104
101
113
121
101
129
102
121
159
1972
1972
1988
1977
1972
1963
1956
1972
1968
1996
1968
1960
13
13
3
2
13
9
12
1
15
20
5
17
1994 1993 1994 1993 1993 -
80
75
93
61
77
18
18
18
18
18
72
67
72
74
67
1997
1998
1996
1998
1993
14
22
24
1
22
1992 1993 1993 -
18
18
18
18
18
18
18
18
109
47
98
1996
1999
1996
8
8
8
1992 1995 - 98
1992 - 98
83
70
70
98
83
78
109
102
74
109
1997
1996
14
25
18
18
1997
1998
1995
1996
1968
1996
1996
1996
1996
1968
1996
1960
1996
1996
1996
1996
1976
8
15
10
20
15
20
2
20
20
5
20
17
20
25
20
20
13
1996
1996
20
20
MAIN STATIONS (* combined auto-manual stations)
record
7025250
7027320
7034482
7098600
7028124
7016294
7060400
7066685
7055120
7052605
7040440
7047910
YUL
YHU
WMJ
ZVO
YSC
YQB
YBG
YRJ
YYY
YGP
YBC
YZV
Montreal-Dorval *
Saint-Hubert *
Maniwaki *
Val-d'Or *
Sherbrooke *
Quebec City *
Bagotville
Roberval
Mont-Joli
Gaspé
Baie-Comeau *
Sept-Iles
FROM LAC ST-FRANÇOIS TO QUEBEC CITY
record
record
record
record
702FQLF
702FHL8
702327X
7018562
7025442
WBZ
WVQ
WHM
WTY
WNQ
St-Anicet
Ste-Anne-de-Bellevue
Montreal East
Trois-Rivières
Nicolet
FROM QUÉBEC CITY TO ÎLE ROUGE
record
70132G9
701Q009
7041JG6
701LBPH
702MKNL
7056616
7046059
7042BP9
WER
WVY
WTN
WIG
WLU
WNH
WQD
WAF
St-François-Ile d'Orléans
Villeroy
Cap Tourmente
Ile aux Grues
Lauzon
Rivière-du-Loup
Pointe de l'Islet
Ile Rouge
LOWER ST. LAWRENCE
record
record
record
record
7041312
7054096
705LKPQ
7056068
7055120
705S002
7051163
7052605
7055422
7040440
704F0PN
7047910
7043B79
7056202
7053038
7043018
7040813
WIS
WST
WQO
WYQ
YYY
WSG
WSF
YGP
WOC
YBC
WTG
YZV
WQR
WBY
WHP
YGV
YBX
Amqui
La Pocatière
Île Bicquette
Pointe-au-Père
Mont-Joli
Cap Chat
Cap Madeleine
Gaspé
New Carlisle
Baie-Comeau *
Pointe-des-Monts
Sept-Iles
Île aux Perroquets
Port Menier
Heath Point
Havre-St-Pierre *
Blanc Sablon *
1997 1995 1994 1996 1955 1996 1992 1977 1994 1965 1992 1955 1994 1992 1992 1994 1973 -
60
118
n.a.
122
100
115
99
89
97
93
104
72
109
117
96
96
80
18
18
18
18
18
18
18
18
18
18
18
18
18
19
82
83
91
93
129
122
128
102
96
121
100
159
139
95
119
119
148
7044328
7053KGR
WBT
WGR
Longue-Pointe-de-Mingan
Magdalen Islands
1994 1995 -
68
94
18
18
76
108
December 21, 2000
3