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Monthly "30 Days"

Seasonal "3 Months"


Current Temperature and Precipitation Deterministic Forecasts

Lead Time : 0-3 month 3-6 month 6-9 month 9-12 month
Temperature : Map Map Map Map
Table Table Table Table
Precipitation : Map Map Map Map
Table Table Table Table

Forecasts Issued at the Beginning of the Previous Month

Lead Time : 0-3 month 3-6 month 6-9 month 9-12 month
Temperature : Map Map Map Map
Table Table Table Table
Precipitation : Map Map Map Map
Table Table Table Table

Forecasts Issued Two Months ago

Lead Time : 0-3 month 3-6 month 6-9 month 9-12 month
Temperature : Map Map Map Map
Table Table Table Table
Precipitation : Map Map Map Map
Table Table Table Table

What do these maps represent ?
The upper panel shows the seasonal air temperature or precipitation anomaly forecasts. The forecast are presented in 3 categories: below normal, near normal and above normal. The lower panel illustrates the skill (percent correct) associated to the forecast.The forecast values for more than 100 locations in Canada are also shown at the "Table" links.
Please take into account the skill map (lower panel) when you use the forecast map (upper panel). To use the forecasts optimally it is strongly recommended to read carefully the user guide.

How are these forecasts produced ?
The 0-3 month forecasts are made using 2 numerical weather prediction models while the longer lead times forecasts are produced with a statistical model (3-12 months).


Current Temperature and Precipitation Probabilistic Forecasts

Temperature : Maps Reliability
Precipitation : Maps Reliability

Probabilistic Forecasts Issued at the Beginning of the Previous Month

Temperature : Maps Reliability
Precipitation : Maps Reliability

Probabilistic Forecasts Issued Two Months Ago

Temperature : Maps Reliability
Precipitation : Maps Reliability

What do these maps represent ?
The probability of being below, near or above the normal are shown for the temperature and precipitation. The probabilities are the result of a simple member counting and therefore they are not calibrated. However, a reliability diagram can be used to calibrate the probabilities based on verification of past performance (see the links "Reliability" for temperature and precipitation above). To use the forecasts optimally it is strongly recommended to read carefully the user guide!

How are these forecasts produced?
The current season 1 ensemble consists of 12 model runs: 6 runs from the GEM model and 6 runs from the CCCma GCM2 model (details). The forecast probabilities are calculated by counting the number of individual members in each of the three categories at every location and then dividing by the ensemble size (more).


Skill of the Deterministic Forecast System

Lead Time : 0-3 month 3-6 month 6-9 month 9-12 month
Temperature : J-F-M J-F-M J-F-M J-F-M
F-M-A F-M-A F-M-A F-M-A
M-A-M (Spring) M-A-M (Spring) M-A-M (Spring) M-A-M (Spring)
A-M-J A-M-J A-M-J A-M-J
M-J-J M-J-J M-J-J M-J-J
J-J-A (Summer) J-J-A (Summer) J-J-A (Summer) J-J-A (Summer)
J-A-S J-A-S J-A-S J-A-S
A-S-O A-S-O A-S-O A-S-O
S-O-N (Fall) S-O-N (Fall) S-O-N (Fall) S-O-N (Fall)
O-N-D O-N-D O-N-D O-N-D
N-D-J N-D-J N-D-J N-D-J
D-J-F (Winter) D-J-F (Winter) D-J-F (Winter) D-J-F (Winter)
Precipitation : J-F-M J-F-M J-F-M J-F-M
F-M-A F-M-A F-M-A F-M-A
M-A-M (Spring) M-A-M (Spring) M-A-M (Spring) M-A-M (Spring)
A-M-J A-M-J A-M-J A-M-J
M-J-J M-J-J M-J-J M-J-J
J-J-A (Summer) J-J-A (Summer) J-J-A (Summer) J-J-A (Summer)
J-A-S J-A-S J-A-S J-A-S
A-S-O A-S-O A-S-O A-S-O
S-O-N (Fall) S-O-N (Fall) S-O-N (Fall) S-O-N (Fall)
O-N-D O-N-D O-N-D O-N-D
N-D-J N-D-J N-D-J N-D-J
D-J-F (Winter) D-J-F (Winter) D-J-F (Winter) D-J-F (Winter)

What do these maps represent ?
By clicking on the above links, you can see the spatial skill distribution of the forecast system. The colored areas show that the system is better than pure chance forecast while the grey areas indicate the areas where the current forecast system has no predictive skill. Please read this before doing further interpretation of the maps.


Verification of Past Forecasts

Chart:
Period Year Parameter
Contingency Tables:
Period Year Parameter

Using this menu, you can see the previous 0-3 month forecast charts produced by Environment Canada since 1996 and the corresponding observed charts. The scores (from the contingency tables) obtained with these forecasts are also available. To see your selection please click the view button.


Climatology of Temperature and Precipitation

Season : Average Threshold Table
Temperature : J-F-M J-F-M J-F-M
F-M-A F-M-A F-M-A
M-A-M (Spring) M-A-M (Spring) M-A-M (Spring)
A-M-J A-M-J A-M-J
M-J-J M-J-J M-J-J
J-J-A (Summer) J-J-A (Summer) J-J-A (Summer)
J-A-S J-A-S J-A-S
A-S-O A-S-O A-S-O
S-O-N (Fall) S-O-N (Fall) S-O-N (Fall)
O-N-D O-N-D O-N-D
N-D-J N-D-J N-D-J
D-J-F (Winter) D-J-F (Winter) D-J-F (Winter)
Precipitation : J-F-M J-F-M J-F-M
F-M-A F-M-A F-M-A
M-A-M (Spring) M-A-M (Spring) M-A-M (Spring)
A-M-J A-M-J A-M-J
M-J-J M-J-J M-J-J
J-J-A (Summer) J-J-A (Summer) J-J-A (Summer)
J-A-S J-A-S J-A-S
A-S-O A-S-O A-S-O
S-O-N (Fall) S-O-N (Fall) S-O-N (Fall)
O-N-D O-N-D O-N-D
N-D-J N-D-J N-D-J
D-J-F (Winter) D-J-F (Winter) D-J-F (Winter)

What do these maps represent ?
By clicking on the links under "Average" you can see a map of mean observed value of temperature (in degrees Celsius) or precipitation accumulation (in millimetre or mm) for the corresponding season. The Canadian surface stations data used cover the 1963-1993 period for the temperature while it cover 1961-1990 for the precipitation.

The links under "Threshold" present maps of the value used as a threshold to classify the observed anomaly in one of the three categories (above, near or below normal). The climatology and threshold values for more than 100 locations in Canada are also shown at the links under "Table".


Composite analysis of Continental Snow Coverage, Sea Ice Coverage, and Sea Surface Temperature Anomalies

Static Images : daily and the 30-Day average
Animations (JavaScript Required)

One-year animation of SST Anomalies, Snow Coverage, and Sea Ice Coverage (Pacific Ocean and the Americas). This animation is well suited to observing the ENSO SST Anomaly phenomenon during El-Niño/La Niña years. It also displays the yearly cycle of snow coverage over the northern landmasses.

30-day animation of SST anomalies, Snow Coverage, and Sea Ice Coverage (North America). One can observe the progression or retreat of the snow coverage over North America during the past month.

SST anomalies, Ice, Snow : a view from space Global view of the current composite analysis, from the perspective of an observer located in Space, 30 degrees north of the Equator. The observer is watching a static analysis of SST Anomalies, Sea Ice, and Snow Coverage, projected on a rotating earth globe. The contours are lines of equal 500 HPa heights, providing a snapshot of the upper air currents which steer weather systems.

The climate of Canada is mainly influenced by the sea surface temperature and the sea ice extent of the surrounding seas as well as by the snow cover. Using the above links, you can have access to maps of the current state of these fields as analysed by the CMC. You can also look at some animations to follow the evolution of the conditions during the last months.


On-line Model Data

The fields forecast by the numerical weather prediction models are available in real time (first day of the each season) at the web site of the Canadian Centre for Climate Modelling and Analysis . On this site you can also find the data produce during the Historical Forecasting Project. The historical forecasts 1969-1994 were used to prepare the models climatologies that are used to calculate the forecast anomalies. This data was also used to draw the skill maps.


Environment Canada El Niño and La Niña pages

The ENSO phenomena (El Niño and La Niña) is one of the major factor influencing the year to year fluctuations of seasonal temperature and precipitation anomalies in Canada. You can learn more about the worldwide and regional effects of the phenomena as well as follow its evolution by going to the Environment Canada web pages listed above.




Created: 2002-12-31
Modified: 2004-07-13
Reviewed: 2002-12-31
URL of this page: http://www.weatheroffice.ec.gc.ca/saisons/index_e.html

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Environment Canada's World Wide Web Site.