Hourly Weather Forecast - Mercersburg, PA

12 AM
36°F
0%
4mph
SSW
Mostly Cloudy
Humidity
61%
Feels like
33°F
Dew Point
24°F
1 AM
36°F
0%
4mph
SSW
Partly Cloudy
Humidity
62%
Feels like
34°F
Dew Point
24°F
2 AM
36°F
0%
3mph
SW
Partly Cloudy
Humidity
63%
Feels like
34°F
Dew Point
25°F
3 AM
36°F
0%
3mph
SW
Mostly Cloudy
Humidity
65%
Feels like
36°F
Dew Point
26°F
4 AM
36°F
0%
3mph
WSW
Mostly Cloudy
Humidity
67%
Feels like
34°F
Dew Point
27°F
5 AM
36°F
0%
4mph
WSW
Mostly Cloudy
Humidity
70%
Feels like
33°F
Dew Point
27°F
6 AM
36°F
0%
4mph
W
Partly Cloudy
Humidity
73%
Feels like
32°F
Dew Point
28°F
7 AM
37°F
0%
5mph
W
Partly Cloudy
Humidity
72%
Feels like
32°F
Dew Point
29°F
7:29 AM
8 AM
38°F
0%
6mph
W
Partly Cloudy
Humidity
67%
Feels like
33°F
Dew Point
28°F
9 AM
40°F
0%
8mph
W
Mostly Sunny
Humidity
60%
Feels like
34°F
Dew Point
27°F
10 AM
41°F
0%
9mph
W
Sunny
Humidity
54%
Feels like
35°F
Dew Point
26°F
11 AM
42°F
0%
10mph
W
Sunny
Humidity
48%
Feels like
36°F
Dew Point
24°F
12 PM
42°F
0%
11mph
W
Sunny
Humidity
44%
Feels like
36°F
Dew Point
22°F
1 PM
42°F
0%
12mph
W
Sunny
Humidity
42%
Feels like
35°F
Dew Point
21°F
2 PM
41°F
0%
12mph
WNW
Sunny
Humidity
42%
Feels like
34°F
Dew Point
20°F
3 PM
40°F
0%
11mph
WNW
Sunny
Humidity
42%
Feels like
33°F
Dew Point
19°F
4 PM
38°F
0%
11mph
WNW
Sunny
Humidity
43%
Feels like
30°F
Dew Point
17°F
4:50 PM
5 PM
35°F
0%
10mph
WNW
Clear
Humidity
45%
Feels like
28°F
Dew Point
16°F
6 PM
33°F
10%
9mph
WNW
Clear
Humidity
47%
Feels like
26°F
Dew Point
15°F
7 PM
31°F
10%
8mph
WNW
Clear
Humidity
49%
Feels like
24°F
Dew Point
15°F
8 PM
30°F
10%
7mph
WNW
Clear
Humidity
49%
Feels like
23°F
Dew Point
14°F
9 PM
29°F
10%
7mph
WNW
Clear
Humidity
50%
Feels like
22°F
Dew Point
13°F
10 PM
29°F
10%
6mph
WNW
Clear
Humidity
50%
Feels like
22°F
Dew Point
12°F
11 PM
28°F
10%
6mph
WNW
Clear
Humidity
51%
Feels like
21°F
Dew Point
12°F

Rainfall and Snowfall Totals Through Thursday

Pineapple Express Slams Northwestern U.S.

The atmospheric river this week will keep buffeting the Pacific Northwest with heavy rain, snow, and high winds.

Wednesday'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 person standing in a snowy forest with their back to the camera. They are bundled up in a white hat and a brown jacket. (Image by StockSnap from Pixabay)

Common Cold Weather Illnesses

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

Cold Air Damming - Cause And Effects

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