Your most common wind direction by month

Turku (8 directions),

January: SW, SE tied

February: E

March: SE

April: S, SE tied

May: E, SE tied

June: S

July: SW

August: E

September: E, SE tied

October: SE

November: SE

December: SE


Helsinki Airport:


January: SW

February: SW

March: SW

April: SW

May: SW

June: SW

July: SW

August: SW

September: SW

October: SW

November: SW

December: SW

January:  NNE
February: NNE
March:      N
April:        N
May:        N
June:       N
July :       N
August:   N
Sept:      NNE
Oct:        NNE
Nov:       NNE
Dec:       NNE

Darwin has pronounced seasonal variation in wind direction, as one would expect in a monsoonal wet/dry climate
Basically the Asian monsoon blows in from the west/northwest from about Xmas Day until early April.
During monsoonal break periods, convectional storms may form, with 'gulf lines' coming in from the east.
May through to September, the dry season, the winds reverse and blow strongly accross the continent from the south east over the Top End, bringing low DP's, lower temps and heightened fire danger periods.
Aug-Sept, winds may blow very strongly from the south east, often causing wind warnings for small boats along the coasts.
Late Sept - mid Dec are the 'build up' months, light variable winds from the east/south east. The build up storms generally come from the east, and are often gusty, sometimes 30 to 40 knots.
Where I live ( close to the coast ), I get northwesterly afternoon sea breezes at any time of the year.

Can't find data by month, but annually SSWlys are the most common, followed by SWly and Wly winds.

Southerly winds are more common in summer. Easterly winds seem to be most common in spring.