Friday 24 May 2019

Weather synopsis (May 23, 2019; Wk 07)

Weather synopsis – This past week (May 8-15, 2019) the average temperature was approximately 1 °C cooler than normal (Fig. 1). The warmest temperatures were observed in AB and with conditions much cooler in SK and MB.  

This week, May 15-21, 2019, cool, dry conditions continued to occur across the prairies. Though temperatures are warming up, early growing season daily average temperatures continue to be cooler than normal. This past week the average temperature was approximately 2.5 °C cooler than normal (Fig. 2). The warmest temperatures were observed in central AB, southeast SK and southwest MB (Fig. 2).  
Figure 1.  Average Temperature (°C) across the Canadian prairies the past seven days (May 15-21, 2019).


Figure 2.  Average Temperature (°C) across the Canadian prairies the past 30 days (April 21-May 21, 2019).

Average 30 day temperatures were approximately 3 °C cooler than average (Fig. 3). Across the prairies, average temperatures (April 23 – May 20, 2019)  were 2 to -3 °C below normal with central SK having temperatures that were 3 to 4 °C cooler than average with well below average temperatures occurring in a large area of central SK. 


Figure 3.  Mean temperature differences from Normal across the Canadian prairies from April 23-May 20, 2019.
Image has not been reproduced in affiliation with, or with the endorsement of the 
Government of Canada and was retrieved (21May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

This week (May 15-21, 2019), the seven-day cumulative rainfall indicated that minimal rain was observed across large areas of SK (Fig. 4). Most locations reported less than 5 mm.  Wetter conditions were reported in a corridor between Lethbridge and Calgary AB. 

Figure 4. Cumulative precipitation observed the past seven days across the Canadian prairies (May 15-21, 2019).

Across the prairies, rainfall amounts for the past 30 days (April 21-May 21, 2019) have been approximately 50% of normal (Fig. 5).  Rainfall in southwest SK has increased.  Between Brandon MB and Lloydminster SK 30-day rainfall amounts are well below average (Fig. 5). Growing season rainfall (April 1 – May 21) amounts have been well below average for most of the prairies, particularly in west central SK and eastern regions of AB (Fig. 6).  For this growing season, almost all of the prairies have received rainfall that is 85 percent or less than average (Fig. 7).
Figure 5.  Cumulative precipitation observed the past 30 days across the Canadian prairies (April 21-May 21, 2019).

Figure 6.  Cumulative precipitation observed for the growing season across the Canadian prairies (April 1-May 21, 2019).
Figure 7. Percent of Average precipitation across the Canadian prairies for the growing season (April 1-May 21, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and 
was retrieved (21May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true


Soil moisture values are low across most of the prairies. Near normal soil moisture is predicted to occur in an area extending from Swift Current, west to Lethbridge and north to Edmonton and Grande Prairie (Fig. 8).

Figure 8. Modeled soil moisture (%) across the Canadian prairies (up to May 21, 2019).


The growing degree day map (GDD) (Base 5 ºC, April 1-May 20, 2019) is below (Fig. 9):
Figure 9.  Growing degree day (Base 5 ºC) across the Canadian prairies for the growing season (April 1-May 20, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true


The growing degree day map (GDD) (Base 10 ºC, April 1-May 15, 2019) is below (Fig. 10):
Figure 10.  Growing degree day (Base 10 ºC) across the Canadian prairies for the growing season (April 1-May 20, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The lowest temperatures (°C) observed the past seven days range from -10 to 2 °C in the map below (Fig. 11).
Figure 11.  Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 14-20, 2019).Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The highest temperatures (°C) observed the past seven days range from -10 to 2 °C in the map below (Fig. 12).
Figure 12.  Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 14-20, 2019).Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The maps above are all produced by Agriculture and Agri-Food Canada.  Growers may wish to bookmark the AAFC Drought Watch Maps for the growing season.