Wednesday 8 April 2015

Wind Trajectories for the Canadian Prairies (April 7, 2015)

Wind trajectories Related to Diamondback Moth (DBM) and Aster Leafhopper Introductions

BACKGROUND:  Potential wind events capable of carrying insect pests from source areas in the USA can be identified by following trajectories for air parcels through time. High altitude air masses, originating from southern locations, frequently move northerly to Canadian destinations. Insect pest species such as Diamondback moth and Aster leafhoppers, traditionally unable to overwinter above the 49th parallel, can utilize these air masses in the spring to move north from Mexico and the United States (southern or Pacific northwest). Data acquired from Environment Canada is compiled by Olfert et al. (AAFC-Saskatoon) to track and model high altitude air masses in the spring with respect to potential introductions of insect pests onto the Canadian prairies. Each week, backward and forward trajectories are examined with respect to source and destination in the following manner. The forward trajectories are prognostic (5 days into the future) based on forecast wind fields while the backward trajectories are diagnostic and based on analyzed wind fields (5 days previous).



FOR THE WEEK OF APRIL 3-7, 2015:  Wind trajectory data processing by AAFC-Saskatoon Staff began in April.  Reverse Trajectories track arriving air masses back to their point of origin while Forward Trajectories predict favourable winds expected to arrive across the Canadian Prairies for the week of April 3-7, 2015:

Reverse trajectories (RT) 
Pacific Northwest (PNW) – The number of reverse trajectories from Prairie locations with links to the PNW continues to be relatively high. the following 25 locations had RT’s, originating from the PNW, that crossed the prairies on April 1 and 2, 2015. Of particular interest were the northern AB locations reported for April 7.

Reverse Trajectories Originating from PNW Arriving at Prairie Locations
Location ID
Arriving Date
(dd-m-year)
Latitude
Longitude
WANHAM_AB
07/04/2015
55.7
-118.4
VEGREVILLE_AB
07/04/2015
53.5
-112
SEDGEWICK_AB
07/04/2015
52.8
-111.7
RYCROFT_AB
07/04/2015
55.8
-118.7
REGINA_SK
07/04/2015
50.5
-104.5
PROVOST_AB
07/04/2015
52.4
-110.3
OLDS_AB
07/04/2015
51.8
-114.1
LETHBRIDGE_AB
07/04/2015
49.7
-112.8
KINDERSLEY_SK
07/04/2015
51.5
-109.1
GRENFELL_SK
07/04/2015
50.4
-102.9
GRANDE_PRAIRIE_AB
07/04/2015
55.2
-118.8
GAINSBOROUGH_SK
07/04/2015
49.2
-101.4
FORT_VERMILION_AB
07/04/2015
58.4
-116
BEISEKER_AB
07/04/2015
51.4
-113.5
ANDREW_AB
07/04/2015
53.9
-112.3
VEGREVILLE_AB
06/04/2015
53.5
-112
SEDGEWICK_AB
06/04/2015
52.8
-111.7
OLDS_AB
06/04/2015
51.8
-114.1
LETHBRIDGE_AB
06/04/2015
49.7
-112.8
GRANDE_PRAIRIE_AB
06/04/2015
55.2
-118.8
BEISEKER_AB
06/04/2015
51.4
-113.5
LETHBRIDGE_AB
05/04/2015
49.7
-112.8
KINDERSLEY_SK
05/04/2015
51.5
-109.1
BEISEKER_AB
05/04/2015
51.4
-113.5
LETHBRIDGE_AB
04/04/2015
49.7
-112.8



Forward Trajectories (FT)
Forward trajectories originating from the following locations are predicted to cross the prairies within the next five days:
  Forward Trajectory source locations predicted to cross the Canadian prairies  
Location ID
Initial Date
(dd-m-year)
BOZEMAN_MONTANA
07/04/2015
EASTERN_WASHINGTON
07/04/2015
IMPERIAL_VALLEY_CALIFORNIA
07/04/2015
MEXICALI_MEXICO
07/04/2015
MOSCOW_IDAHO
07/04/2015
BOZEMAN_MONTANA
06/04/2015
EASTERN_WASHINGTON
06/04/2015
LOUISIANA
06/04/2015
MANHATTAN_KANSAS
06/04/2015
MOSCOW_IDAHO
06/04/2015
SANTA_MARIA_CALIFORNIA
06/04/2015
BOZEMAN_MONTANA
05/04/2015
EASTERN_WASHINGTON
05/04/2015
MANHATTAN_KANSAS
05/04/2015
EASTERN_WASHINGTON
04/04/2015
MANHATTAN_KANSAS
04/04/2015
MOSCOW_IDAHO
04/04/2015
EASTERN_WASHINGTON
03/04/2015
MOSCOW_IDAHO
03/04/2015

The April 6 forward trajectory from Santa Maria, California, is predicted to cross over southern Alberta on April 11. The forward trajectory from Mexicali should cross southern Manitoba about April 8. The Imperial Valley trajectory is predicted to cross southern Manitoba on April 9.  Though the prairies were forecasted to expect snow (April 7), conditions are predicted to warm up over the next few days.

Forecast for Lethbridge:

Forecast for Winnipeg: