86°
Isolated Rain Showers
15%
72
Washington County, MD · Lake
Greenbrier State Park
21843 National Pike, Boonsboro, MD 21713
42-acre man-made freshwater lake with a white-sand swim beach on South Mountain northeast of Boonsboro. Popular with DC/Baltimore day-trippers, so MD DNR now requires advance reservations on weekends/holidays Memorial Day–Labor Day.
Today's Conditions
Great day for a beach walk.
86°F air
Full NWS forecast for This Afternoon
Isolated rain showers before 4pm. Mostly sunny, with a high near 86. Southwest wind around 12 mph, with gusts as high as 18 mph. Chance of precipitation is 20%.
Tonight
A slight chance of rain showers after 5am. Partly cloudy, with a low around 71. South wind 6 to 12 mph, with gusts as high as 18 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
Weather
- 86°F air — ideal beach weather
72 /100
great
68 Sunbathe
77 Walk
69 Fish
75 Photo
Best for walking today
Atmosphere
Air Temp
86°F
Clear
Wind
12 mph
SW
Rain
15%
This Afternoon
UV Peak
8 Very High
High 12 PM–02 PM · burn in ~25m
Burn-free before 09 AM & after 05 PM
Tomorrow
84°F
Slight Chance Rain Showers then Chance Showers And Thunderstorms
Water
Water Temp
—
Sun & Moon
Sunrise
6:46 AM
Sunset
7:29 PM
Moon · 5%
Waning Crescent
Spring tides — bigger range
7-Day Beach Day Forecast
84°
Slight Chance Rain Showers then Chance Showers And Thunderstorms
38%
42
80°
Mostly Sunny
2%
87
79°
Showers And Thunderstorms Likely
65%
24
84°
Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms
17%
57
83°
Mostly Sunny
4%
85
85°
Mostly Sunny
8%
82
What to Bring Today
- critical SPF 50 sunscreen UV index 8 — very high
- recommended Sturdy umbrella + sand anchor 12 mph wind
Always remember water bottle, trash bag (leave no trace).
Best Fishing Times Today
Solunar theory: fish activity peaks at moon transits (major) and moonrise/moonset (minor). All times local.
Major
10:40 PM - 12:40 AM
Minor
4:40 AM - 5:40 AM
Major
11:00 AM - 1:00 PM
Minor
6:20 PM - 7:20 PM
Beach Info
Parking
State park lot.
Dogs
Dogs permitted on leash in designated areas; not on swim beach.
Entry Fee
$3/person MD resident, $5/person out-of-state (May/Sep weekends); higher in-season. Advance day-use reservation required weekends & holidays Memorial Day–Labor Day.
Address
21843 National Pike, Boonsboro, MD 21713
Amenities
Frequently Asked
Is it safe to swim at Greenbrier State Park today?
Greenbrier State Park shows a live water-quality reading (bacteria levels) and today's swim-safety score at the top of this page, refreshed on every update. Seasonal lifeguards patrol the swim area in summer — follow their flags. Always review the current advisories, surf, and rip-current notes before getting in the water.
Is Greenbrier State Park dog-friendly?
Dogs permitted on leash in designated areas; not on swim beach.
Is there an entry fee at Greenbrier State Park?
$3/person MD resident, $5/person out-of-state (May/Sep weekends); higher in-season. Advance day-use reservation required weekends & holidays Memorial Day–Labor Day.
Are there lifeguards at Greenbrier State Park?
Yes. Seasonal lifeguards patrol Greenbrier State Park during the summer swim season (typically Memorial Day through Labor Day). Outside that window, swim at your own risk.
What amenities are at Greenbrier State Park?
Amenities at Greenbrier State Park include lifeguards, beach, camping, boat launch, boat rentals, fishing, trails, restrooms.
When is the water warmest at Greenbrier State Park?
Inland lakes peak in July and August at 75-80°F and hold warmth longer than tidal beaches. Swimming comfortable from mid-June through September.
Where is Greenbrier State Park located?
Greenbrier State Park is in Washington County, MD, at 21843 National Pike, Boonsboro, MD 21713.
Nearby Beaches
Updated · Data from NOAA, NWS