Best Time to See Jellyfishes in Maryland
August, July and September is the best time to see jellyfishes in Maryland. Based on 1,444 verified iNaturalist observations, here is exactly when jellyfishes are most active across the year in Maryland.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 2, 2026.
1,444 verified observations of jellyfishes in Maryland, recorded across 12 months of the year on iNaturalist.
When jellyfishes are recorded in Maryland
Peak month
August
291 records (20.2% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 27 | 1.9% |
| February | 35 | 2.4% |
| March | 115 | 8% |
| April | 102 | 7.1% |
| May | 56 | 3.9% |
| June | 95 | 6.6% |
| Julypeak | 248 | 17.2% |
| Augustpeak | 291 | 20.2% |
| Septemberpeak | 221 | 15.3% |
| October | 160 | 11.1% |
| November | 78 | 5.4% |
| December | 16 | 1.1% |
Jellyfishes you are most likely to see
| Species | Verified observations |
|---|---|
| Bay Nettle | 858 |
| Atlantic Lion's Mane Jelly | 185 |
| Dwarf Lion's Mane Jelly | 53 |
| Common Moon Jelly | 32 |
| Southern Moon Jelly | 30 |
| Mushroom Jelly | 28 |
| Atlantic Sea Nettle | 12 |
| Cannonball Jelly | 5 |
Weather to expect, source Open-Meteo
Typical weather in Maryland
Recent typical conditions by month, so you can plan a trip around both when jellyfishes are active and what the weather is doing. The best months to look for jellyfishes sit around 62 to 89 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 44°F | 30°F | 3.3" |
| Feb | 48°F | 31°F | 3.9" |
| Mar | 56°F | 37°F | 3.9" |
| Apr | 66°F | 45°F | 4.7" |
| May | 73°F | 54°F | 4.7" |
| Jun | 83°F | 64°F | 5.4" |
| Julbest time | 89°F | 70°F | 7.3" |
| Augbest time | 85°F | 69°F | 7.6" |
| Sepbest time | 79°F | 62°F | 4.9" |
| Oct | 69°F | 52°F | 4.9" |
| Nov | 56°F | 40°F | 3.2" |
| Dec | 49°F | 34°F | 4.8" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Maryland. Weather varies year to year, so treat these as a guide.
Sightings of jellyfishes in Maryland peak in August, when 291 of the year's 1,444 verified observations are logged — about 20.2% of the annual total. Activity stays high through August, July and September.
The quietest stretch is December, when jellyfishes are hardest to find — December sees just 16 records. If a reliable sighting matters, plan around the peak window rather than the off-season.
The jellyfishes you are most likely to encounter in Maryland are Bay Nettle, Atlantic Lion's Mane Jelly and Dwarf Lion's Mane Jelly — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see jellyfishes in Maryland
- Antietam National Battlefield — National Battlefield
- Appalachian National Scenic Trail — National Scenic Trail
- Assateague Island National Seashore — National Seashore
- Captain John Smith Chesapeake National Historic Trail — National Historic Trail
- Chesapeake & Ohio Canal National Historical Park — National Historical Park
- Chesapeake Bay
Frequently asked questions
What is the best month to see jellyfishes in Maryland?+
August is the single best month, and the broader peak window runs through August, July and September, based on 1,444 verified iNaturalist observations.
When are jellyfishes hardest to see in Maryland?+
December is the quietest month for jellyfishes in Maryland, with only 16 verified records.
Are jellyfishes active year-round in Maryland?+
Jellyfishes are recorded in 12 of 12 months in Maryland, so they can be seen year-round, with a clear peak in August.
More places to see jellyfishes
More wildlife in Maryland