Monthly outlook for Antietam, MD: average high 84.7°, average low 64.1°. That is 0.8° above the climate normal for August. Precipitation is expected on 8 days (about 1.3 inches), against a normal of 5 days and 1.6 inches. The warmest day looks like 10 August (95.4°), the coolest 22 August (54.4°).
84.7°/64.1°
Average high / low
+0.8°
Above normal
8 / 5
Wet days / normal
1.3 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
84.6°
83.9°
+0.4°
19 August – 28 August
84.9°
82.7°
+1.2°
29 August – 7 September
at normal
81.5°
—
August records over 66 years
99.7°17 August 1988All-time high
48.9°30 August 1986All-time low
Climate normals and records are computed from the nearest reference point — Rohrersville (4 mi).
Mon, 1095° / 71°0.3
95 °
Antietam, Monday, 10 August
Rain. High 95°, low 71°.
Pressure30.03 inHg
Wind7 mph W
Humidity52%
Visibility6.2 mi
Dew point65°
Tue, 1188° / 67°0.2
88 °
Antietam, Tuesday, 11 August
Heavy rain. High 88°, low 67°.
Pressure29.97 inHg
Wind10.3 mph W
Humidity54%
Visibility6.2 mi
Dew point65°
Wed, 1291° / 68°0.1
91 °
Antietam, Wednesday, 12 August
Light rain. High 91°, low 68°.
Pressure29.77 inHg
Wind7.8 mph W
Humidity58%
Visibility6.2 mi
Dew point65°
Thu, 1384° / 66°0.11
84 °
Antietam, Thursday, 13 August
Light rain. High 84°, low 66°.
Pressure29.85 inHg
Wind17 mph NW
Humidity31%
Visibility—
Dew point48°
Fri, 1477° / 59°0
77 °
Antietam, Friday, 14 August
Overcast. High 77°, low 59°.
Pressure30.09 inHg
Wind8.4 mph S
Humidity40%
Visibility—
Dew point47°
Sat, 1583° / 56°0
83 °
Antietam, Saturday, 15 August
Clear. High 83°, low 56°.
Pressure30.18 inHg
Wind11.2 mph NW
Humidity30%
Visibility—
Dew point45°
Sun, 1684° / 57°0
84 °
Antietam, Sunday, 16 August
Partly cloudy. High 84°, low 57°.
Pressure30.15 inHg
Wind9.2 mph SE
Humidity36%
Visibility—
Dew point50°
Mon, 1778° / 66°0.1
78 °
Antietam, Monday, 17 August
Light rain. High 78°, low 66°.
Pressure30.06 inHg
Wind16.5 mph S
Humidity67%
Visibility—
Dew point61°
Tue, 1878° / 65°0.2
78 °
Antietam, Tuesday, 18 August
Rain. High 78°, low 65°.
Pressure30.03 inHg
Wind7.1 mph SE
Humidity76%
Visibility—
Dew point65°
Wed, 1989° / 64°0.04
89 °
Antietam, Wednesday, 19 August
Light rain. High 89°, low 64°.
Pressure29.88 inHg
Wind11.1 mph SE
Humidity52%
Visibility—
Dew point63°
Thu, 2079° / 66°0.16
79 °
Antietam, Thursday, 20 August
Light rain. High 79°, low 66°.
Pressure29.77 inHg
Wind20.1 mph NW
Humidity41%
Visibility—
Dew point52°
Fri, 2181° / 57°0
81 °
Antietam, Friday, 21 August
Clear. High 81°, low 57°.
Pressure29.91 inHg
Wind13.3 mph NW
Humidity30%
Visibility—
Dew point44°
Sat, 2284° / 54°0
84 °
Antietam, Saturday, 22 August
Partly cloudy. High 84°, low 54°.
Pressure30.06 inHg
Wind7.2 mph SE
Humidity33%
Visibility—
Dew point47°
Sun, 2385° / 67°0.06
85 °
Antietam, Sunday, 23 August
Light rain. High 85°, low 67°.
Pressure29.94 inHg
Wind10.8 mph S
Humidity61%
Visibility—
Dew point66°
Mon, 2492° / 69°0
92 °
Antietam, Monday, 24 August
Clear. High 92°, low 69°.
Pressure29.94 inHg
Wind15.5 mph W
Humidity28%
Visibility—
Dew point52°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2583° / 65°0.05
83 °
Antietam, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high83°
Average low65°
Average precipitation0.05 in
Chance of precipitation18%
Record high96° (2007)
Record low54° (1971)
Wed, 2684° / 65°0.05
84 °
Antietam, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high84°
Average low65°
Average precipitation0.05 in
Chance of precipitation23%
Record high94° (1975)
Record low55° (1963)
Thu, 2784° / 66°0.13
84 °
Antietam, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high84°
Average low66°
Average precipitation0.13 in
Chance of precipitation30%
Record high94° (2020)
Record low55° (1969)
Fri, 2884° / 66°0.13
84 °
Antietam, Friday, 28 August
Climate normal for this date — 60-year average.
Average high84°
Average low66°
Average precipitation0.13 in
Chance of precipitation33%
Record high95° (1993)
Record low55° (2025)
Sat, 2983° / 66°0.07
83 °
Antietam, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high83°
Average low66°
Average precipitation0.07 in
Chance of precipitation28%
Record high94° (1973)
Record low49° (1982)
Sun, 3083° / 65°0.06
83 °
Antietam, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high83°
Average low65°
Average precipitation0.06 in
Chance of precipitation27%
Record high94° (1991)
Record low49° (1986)
Mon, 3182° / 65°0.09
82 °
Antietam, Monday, 31 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0.09 in
Chance of precipitation28%
Record high95° (1973)
Record low52° (1986)
Tue, 0181° / 64°0.1
81 °
Antietam, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high81°
Average low64°
Average precipitation0.1 in
Chance of precipitation33%
Record high95° (2010)
Record low52° (1967)
Wed, 0282° / 63°0.09
82 °
Antietam, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high82°
Average low63°
Average precipitation0.09 in
Chance of precipitation32%
Record high96° (2010)
Record low53° (1967)
Thu, 0382° / 64°0.06
82 °
Antietam, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high82°
Average low64°
Average precipitation0.06 in
Chance of precipitation23%
Record high95° (2010)
Record low49° (1967)
Fri, 0481° / 64°0.1
81 °
Antietam, Friday, 4 September
Climate normal for this date — 60-year average.
Average high81°
Average low64°
Average precipitation0.1 in
Chance of precipitation25%
Record high96° (2023)
Record low52° (1997)
Sat, 0581° / 64°0.11
81 °
Antietam, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high81°
Average low64°
Average precipitation0.11 in
Chance of precipitation28%
Record high95° (2023)
Record low52° (1997)
Sun, 0680° / 63°0.24
80 °
Antietam, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.24 in
Chance of precipitation33%
Record high96° (2023)
Record low50° (2000)
Mon, 0780° / 62°0.07
80 °
Antietam, Monday, 7 September
Climate normal for this date — 60-year average.
Average high80°
Average low62°
Average precipitation0.07 in
Chance of precipitation22%
Record high93° (2016)
Record low50° (1984)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Antietam, MD are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Antietam, MD since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.