Status: Ongoing analysis Material from: Linus, Rebecca, Chris
1. Impact
In end of June 2021 North-western U.S and Canada was hit by a record-breaking heatwave that smashed many previous records. In Lytton, British Columbia, the temperature reached 49.6C. Large parts of the village was later burned down by a wildfire.
https://www.bbc.co.uk/news/world-us-canada-57678054
For more discussion on the case, see ECMWF User Forum: Western North America Extreme Heat
2. Description of the event
The plots below show analyses for z500 and T850 from 24 June to 1 July.
3. Predictability
3.1 Data assimilation
3.2 HRES
3.3 ENS
The plots below show forecasts (HRES - red, ENS CF - blue) and observations (black) for Lytton, Canada (50N, 121W) in forecast from 23 June (top) with 6-hourly output and from 28 June with 1-hourly output.
The plots below show 3-day EFI for 2-metre temperature 28-30 June.
The plot below shows the forecast evolution for 3-day (28-30 June) maximum temperature inside the black box outlined above (centred on Lytton). The plot includes HRES (red), ENS distribution (blue box-and-whisker) and model climate (red box-and-whisker). The maximum in the model climate (sample of 1200 forecasts, with time-window day 5-7), is 39.3C.
3.4 Monthly forecasts
The plot below show weekly anomalies of 2-metre temperature valid 28 June - 4 July from different initial dates.
The plot below show weekly anomalies of z500 valid 28 June - 4 July from different initial dates.
