Transcript Convergence Line over the Baltic Sea

Example of Convergence lines
over seas and lakes
Case of convergence over Gulf of
Botnia, Gulf of Finland and lake
Vänern
Pirkko Pylkkö
Finnish Meteorological Institute
(See alsowww.knmi.nl/satrep Satrep Manual)
Cold air streaming from the north
•22 Oct 2003 0930 UTC
•Combination of SEVIRI
channels 0.6, 0.8 and 12.0
µm (1,2,10 similar to
AVHRR 1,2,4)
•Polar stereographic
projection
•MSG resolution helps to
depict local scale
phenomena even in the
Nordic countries
•N.B. there is not much
visible light in the north in
October, channel 10
(IR12.0) is dominating
•22 Oct 2003 0947
UTC
•Combination of
AVHRR channels
0.6, 0.8 and 12.0
µm
•Image confirms
the findings of
previous image and
gives more detail
•Conv. line over
Gulf of Finland has
drifted towards
Estonian coast in
the northerly flow
•22 Oct 2003 0930 UTC
•Combination of SEVIRI
channels 0.6,1.6 and 12.0
µm (similar to AVHRR
1,3A,4)
•Polar stereographic
projection
•Pink colour downstream
indicates ice particles
•In cold climate only
clouds with ice particles
give rain