| Station | 1970's - Number of Years below Normal | 1970's - Number of Years Above Normal | 1980's - Number of Years Below Normal | 1980's - Number of Years Above Normal | 1990's - Number of Years Below Normal | 1990's - Number of Years Above Normal | 1970-1999 - Number of Years Below Normal | 1970-1999 - Number of Years Above Normal |
|---|---|---|---|---|---|---|---|---|
| Aberdeen | 2 | 8 | 9 | 1 | 7 | 3 | 18 | 12 |
| Annapolis | 4 | 4 | 7 | 3 | 5 | 4 | 16 | 11 |
| BWI Airport | 5 | 5 | 8 | 2 | 8 | 2 | 21 | 9 |
| Baltimore City | 4 | 6 | 8 | 2 | 3 | 2 | 15 | 10 |
| Beltsville | 3 | 7 | 7 | 3 | 6 | 2 | 16 | 12 |
| Brighton Dam | 5 | 5 | 6 | 4 | 3 | 5 | 14 | 14 |
| Chestertown | 2 | 8 | 8 | 2 | 8 | 2 | 18 | 12 |
| Cumberland | 4 | 6 | 8 | 2 | 4 | 6 | 16 | 14 |
| Emmitsburg | 2 | 8 | 7 | 3 | 6 | 4 | 15 | 15 |
| Frederick | 3 | 7 | 7 | 3 | 6 | 2 | 15 | 12 |
| Laurel | 4 | 6 | 9 | 1 | 5 | 2 | 13 | 9 |
| Mechanicsville | 1 | 4 | 6 | 2 | 5 | 5 | 12 | 11 |
| Rockville | 1 | 9 | 9 | 0 | 7 | 3 | 17 | 12 |
| Royal Oak | 4 | 6 | 7 | 3 | 6 | 4 | 17 | 13 |
| Woodstock | 3 | 5 | 6 | 4 | 6 | 4 | 15 | 13 |
Click on the station name for a frequency distribution of departures from normal summer precipitation for 1970-1999.
Departures were calculated using 1961-1990 normal monthly precipitation totals.