There were 11 convective periods for September 2004:
Start: 01/04Z End: 01/07Z Flow Regime: SW-2    radar/wind loop
Start: 01/14Z End: 01/23Z Flow Regime: SW-2    radar/wind loop
Start: 09/14Z End: 09/18Z Flow Regime: SW-2    radar/wind loop
Start: 10/10Z End: 10/14Z Flow Regime: SW-2    radar/wind loop
Start: 10/23Z End: 11/01Z Flow Regime: SW-2    radar/wind loop
Start: 11/08Z End: 12/00Z Flow Regime: SW-2    radar/wind loop
Start: 12/16Z End: 13/02Z Flow Regime: SE-1    radar/wind loop
Start: 13/14Z End: 13/21Z Flow Regime: SW-2    radar/wind loop
Start: 17/01Z End: 17/09Z Flow Regime: SW-2    radar/wind loop
Start: 20/12Z End: 21/07Z Flow Regime: Other   radar/wind loop
Start: 29/23Z End: 30/05Z Flow Regime: SW-2    radar/wind loop
 
Start: 01/04Z End: 01/07Z Flow Regime: SW-2    radar/wind loop
 First peak wind >= 20 knots at 010515Z   Last at 010610Z
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 30 knots from 140 degrees for tower 9404 at 054 feet on 010520Z
 
Start: 01/14Z End: 01/23Z Flow Regime: SW-2    radar/wind loop
 First peak wind >= 20 knots at 011925Z   Last at 012210Z
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 21 knots from 045 degrees for tower 1007 at 054 feet on 011935Z
 
Start: 09/14Z End: 09/18Z Flow Regime: SW-2    radar/wind loop
 No peak winds >= 20 knots were reported
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 16 knots from 266 degrees for tower 0397 at 060 feet on 091510Z
 
Start: 10/10Z End: 10/14Z Flow Regime: SW-2    radar/wind loop
 First peak wind >= 20 knots at 101140Z   Last at 101140Z
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 28 knots from 070 degrees for tower 0211 at 054 feet on 101140Z
 
Start: 10/23Z End: 11/01Z Flow Regime: SW-2    radar/wind loop
 No peak winds >= 20 knots were reported
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 18 knots from 066 degrees for tower 0397 at 060 feet on 102350Z
 
Start: 11/08Z End: 12/00Z Flow Regime: SW-2    radar/wind loop
 First peak wind >= 20 knots at 110855Z   Last at 112350Z
 First peak wind >= 35 knots at 111920Z   Last at 111920Z
 No peak winds >= 50 knots were reported
 Max peak wind reported was 40 knots from 068 degrees for tower 1101 at 162 feet on 111920Z
 
Start: 12/16Z End: 13/02Z Flow Regime: SE-1    radar/wind loop
 First peak wind >= 20 knots at 121615Z   Last at 130140Z
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 31 knots from 104 degrees for tower 1102 at 162 feet on 122210Z
 
Start: 13/14Z End: 13/21Z Flow Regime: SW-2    radar/wind loop
 First peak wind >= 20 knots at 131435Z   Last at 132010Z
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 30 knots from 110 degrees for tower 0020 at 204 feet on 131830Z
 
Start: 17/01Z End: 17/09Z Flow Regime: SW-2    radar/wind loop
 First peak wind >= 20 knots at 170100Z   Last at 170735Z
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 25 knots from 148 degrees for tower 1007 at 054 feet on 170130Z
 
Start: 20/12Z End: 21/07Z Flow Regime: Other   radar/wind loop
 First peak wind >= 20 knots at 201200Z   Last at 210700Z
 First peak wind >= 35 knots at 201220Z   Last at 210655Z
 No peak winds >= 50 knots were reported
 Max peak wind reported was 44 knots from 079 degrees for tower 0061 at 204 feet on 210500Z
 
Start: 29/23Z End: 30/05Z Flow Regime: SW-2    radar/wind loop
 No peak winds >= 20 knots were reported
 No peak winds >= 35 knots were reported
 No peak winds >= 50 knots were reported
 Max peak wind reported was 19 knots from 278 degrees for tower 1612 at 054 feet on 300000Z