APRIL 2013


        PROVISIONAL INTERNATIONAL NORMALIZED HEMISPHERIC SUNSPOT NUMBERS


               Date             Ri              Rn              Rs
       __________________________________________________________________

                 1              53              24              29
                 2              66              38              28
                 3              68              38              30
                 4              63              39              24
                 5              77              44              33
                 6              76              56              20
                 7              85              66              19
                 8              82              64              18
                 9              92              63              29
                10              94              61              33
                11              85              51              34
                12              84              51              33
                13              79              44              35
                14              74              29              45
                15              63              17              46
                16              63               9              54
                17              64              10              54
                18              57               8              49
                19              59              16              43
                20              61              42              19
                21              63              52              11
                22              60              41              19
                23              55              41              14
                24              66              46              20
                25              75              55              20
                26              71              51              20
                27              72              39              33
                28              69              32              37
                29              95              39              56
                30             101              40              61
       __________________________________________________________________

       MONTHLY MEAN :          72.4            40.2            32.2

       COOPERATING STATIONS :   70              62              62

                 PILOT STATION : Specola Solare Ticinese, Locarno

       __________________________________________________________________

                   Reproduction permitted if source mentionned
                                Frederic Clette