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The plots below shows analyses of z500 and t850 for the period 2-9 January.
The plot above shows backward trajectories based on 850 hPa winds, starting on 1 January and ending on 9 January around Sofia . Under assumption of no vertical motion, the air parcels originated from north-eastern Russiaat 850 hPa level.
The plots below show EFI and SOT for 2-metre temperature day 1 as a proxy for analysis of how extreme the temperature were from 2 to 9 January.
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The plot below compares the model climate from reforecasts (solid) and observation climatology (dashed).
During the cold period, heavy snowfall also hit south-eastern Europe, e.g Istanbul. The plots below show observations of precipitation on 7 and 8 January and the last forecast before each accumulation period.
3.3 ENS
The plot below show the evolution of ensemble forecasts (blue) and HRES (red dot) for 2-metre temperature in Sodankyla on 5 January 00z. The osbervation was around -40C (see above).
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