Heat Wave and Severe Thunderstorms this Independence Day

A prolonged, dangerous heat wave will persist through the Independence Day weekend across the Ohio Valley, Midwest, and Mid-Atlantic. Numerous temperature records are expected. Clusters of severe thunderstorms will move across parts of the Allegheny Plateau into Mid Atlantic this Independence Day, with potential for widespread damaging winds. Additional severe thunderstorms in the Great Plains. Read More >

Hazardous Weather Conditions

Current conditions at

St Marys County Airport (K2W6)

Lat: 38.32°NLon: 76.55°WElev: 144ft.

Fair

98°F

37°C

Humidity	42%
Wind Speed	SE 3 mph
Barometer	29.90 in
Dewpoint	72°F (22°C)
Visibility	NA
Heat Index	106°F (41°C)
Last update	4 Jul 4:35 pm EDT

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Extended Forecast for

Port Republic MD

Severe T-storm Watch until July 4, 10:00pm

Extreme Heat Warning until July 4, 09:00pm

Click here for hazard details and duration

Severe T-storm Watch

Extreme Heat Warning

Severe T-storm Watch until July 4, 10:00pm
Extreme Heat Warning until July 4, 09:00pm
NOW: Multiple hazards in effect
Click HERE for Details
Independence Day
High: 102 °F
Severe
Thunderstorms
Tonight
Low: 76 °F
Severe
Thunderstorms
then Slight
Chance
Showers
Sunday
High: 95 °F
Sunny
Sunday Night
Low: 74 °F
Showers
Likely then
Slight Chance
T-storms
Monday
High: 90 °F
Showers
Likely then
Showers
Monday Night
Low: 71 °F
Showers
Tuesday
High: 86 °F
Chance
Showers then
Chance
T-storms
Tuesday Night
Low: 70 °F
Chance
T-storms

Detailed Forecast

Independence Day

Showers and thunderstorms likely, mainly after 5pm. Some of the storms could be severe. Partly sunny and hot, with a high near 102. Heat index values as high as 110. Southwest wind 5 to 8 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Tonight

Showers and thunderstorms before midnight, then a slight chance of showers between midnight and 3am. Some of the storms could be severe. Low around 76. South wind around 6 mph becoming calm in the evening. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Sunday

Sunny, with a high near 95. Heat index values as high as 103. Calm wind becoming southeast 5 to 7 mph in the afternoon.

Sunday Night

Showers and thunderstorms likely before 3am, then a slight chance of showers after 5am. Increasing clouds, with a low around 74. South wind 5 to 8 mph becoming northeast in the evening. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Monday

Showers likely, then showers and possibly a thunderstorm after 11am. High near 90. East wind 3 to 7 mph. Chance of precipitation is 90%.

Monday Night

Showers and possibly a thunderstorm before 2am, then a chance of showers and thunderstorms after 2am. Low around 71. Chance of precipitation is 80%.

Tuesday

A chance of showers, with thunderstorms also possible after 2pm. Partly sunny, with a high near 86. Chance of precipitation is 40%.

Tuesday Night

A chance of showers and thunderstorms, mainly before 8pm. Mostly cloudy, with a low around 70. Chance of precipitation is 30%.

Wednesday

Mostly sunny, with a high near 86.

Wednesday Night

Partly cloudy, with a low around 71.