Hourly Weather Forecast - Mercersburg, PA

4 AM
15°F
0%
9mph
WNW
Mostly Clear
Humidity
77%
Feels like
4°F
Dew Point
9°F
5 AM
15°F
0%
8mph
WNW
Mostly Clear
Humidity
79%
Feels like
4°F
Dew Point
9°F
6 AM
14°F
0%
6mph
WNW
Mostly Clear
Humidity
81%
Feels like
5°F
Dew Point
10°F
7 AM
15°F
0%
6mph
WNW
Partly Cloudy
Humidity
81%
Feels like
6°F
Dew Point
10°F
7:25 AM
8 AM
16°F
0%
6mph
W
Partly Cloudy
Humidity
77%
Feels like
7°F
Dew Point
11°F
9 AM
18°F
0%
7mph
W
Mostly Cloudy
Humidity
72%
Feels like
9°F
Dew Point
11°F
10 AM
20°F
0%
8mph
WNW
Mostly Cloudy
Humidity
67%
Feels like
10°F
Dew Point
11°F
11 AM
21°F
10%
8mph
WNW
Mostly Cloudy
Humidity
63%
Feels like
12°F
Dew Point
11°F
12 PM
22°F
10%
7mph
W
Mostly Cloudy
Humidity
61%
Feels like
14°F
Dew Point
11°F
1 PM
24°F
10%
6mph
W
Mostly Cloudy
Humidity
58%
Feels like
16°F
Dew Point
11°F
2 PM
24°F
10%
5mph
W
Cloudy
Humidity
56%
Feels like
18°F
Dew Point
11°F
3 PM
25°F
10%
4mph
W
Cloudy
Humidity
55%
Feels like
20°F
Dew Point
11°F
4 PM
25°F
10%
3mph
WSW
Cloudy
Humidity
55%
Feels like
25°F
Dew Point
11°F
4:47 PM
5 PM
24°F
0%
2mph
SW
Cloudy
Humidity
57%
Feels like
24°F
Dew Point
11°F
6 PM
24°F
0%
2mph
SW
Mostly Cloudy
Humidity
59%
Feels like
24°F
Dew Point
11°F
7 PM
23°F
0%
2mph
SSW
Partly Cloudy
Humidity
61%
Feels like
23°F
Dew Point
11°F
8 PM
22°F
0%
2mph
SSW
Partly Cloudy
Humidity
63%
Feels like
22°F
Dew Point
11°F
9 PM
21°F
0%
1mph
SSW
Partly Cloudy
Humidity
65%
Feels like
21°F
Dew Point
11°F
10 PM
20°F
0%
1mph
SSW
Partly Cloudy
Humidity
67%
Feels like
20°F
Dew Point
11°F
11 PM
20°F
0%
1mph
SW
Partly Cloudy
Humidity
68%
Feels like
20°F
Dew Point
11°F

Wind chill temperatures Monday A.M.

Cold Weather Chills the Nation Down to the Gulf

Extreme cold paired with their wind chill values will shiver much of the nation.

Snowfall forecast through Monday evening.

Mid-Atlantic, Great Lakes Snow Piles Up

Monday's Weather Outlook

Today's Weather Outlook

How to Measure Snow via NWS

How To Measure Snow

Weekly Drought Map for December 11, 2025

Hit-or-Miss Precipitation Leads to Mixed Drought Results

A strong cold-air-damming event from March 20, 2018.

Cold Air Damming - Cause And Effects

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