The species diversity was overall high at most stations sampled along the west coast even if the total cell numbers were not. Different diatoms were found in relatively high cell numbers and for example the genus Pseudo-nitzschia* was common at all stations. Among the dinoflagellates, Karenia mikimotoi was common at a couple of stations. A fluorescens maximum was found at about 20 - 25 meters at most stations. In Skagerrak the maximum was dominated by the dinoflagellate Karenia mikimotoi and in Kattegat the genus Tripos dominated. The coccolithophore Emiliania huxleyi was found in relatively high numbers at several stations. The integrated chlorophyll concentrations were normal at all stations for this month. The filamentous cyanobacterium Aphanizomenon flosaquae was abundant in the northern Baltic Proper and at REFM1V1 in the Kalmar sound. Filamentous cyanobacteria were absent or in very low amounts in the southeastern and southwestern parts of the Baltic Proper. Ciliates, cryptomonads and small colony forming cyanobacteria were numerous. The integrated chlorophyll concentrations were below normal for this month at REFM1V1 in the Kalmar sound and within normal at all of the other Baltic stations.