Observed 3:35 PM EDT at KHEF

Union Mill, VA weather

Mostly sunny and 63°17°, jacket by 8 PM.

Mostly agree

Now 63°17°

Mostly sunny

Wind: 6 mph9 km/h; From the southeast. Up to 6 mph9 km/h through 3 AM
Dew point: 39°4°; Comfortable
UV index: 3Moderate; Moderate until 4 PM · peak 4
Air quality: 31Good; Ozone · tomorrow moderate
Pressure: 30.51 inHg1033 hPa; Falling · −0.05 inHg−1.6 hPa in 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

High 64°18° today at 4 PM
Below 50°10° tonight after 9 PM
Fog tomorrow 8–9 AM
Above 50°10° tomorrow by 10 AM
Fog Monday 7–9 AM

This afternoonNear 63°17° · Clear
TonightDown to 38°3° by 5 AM · Clear
Tomorrow morningUp to 55°13° by 11 AM · Clear
Tomorrow afternoonUp to 66°19° by 4 PM · Clear
Tomorrow nightDown to 39°4° by 5 AM · Clear
Monday morningUp to 60°16° by 11 AM · Partly cloudy
Monday afternoonUp to 71°22° by 2 PM · Clear

Hourly forecast, next 48 hours, in the place's local time
Hour	Conditions	Temperature	Feels like	Precipitation	Wind	Humidity	Cloud cover	UV index
Sat 3p	Partly sunny	63°17° (likely 61°16° to 64°18°)	63°17°	0%	5 mph8 km/h from SE, gusts 8 mph12 km/h	44%	19%	3
Sat 4p	Partly sunny	64°18° (likely 61°16° to 64°18°)	64°18°	0%	5 mph8 km/h from SE, gusts 7 mph11 km/h	43%	26%	1
Sat 5p	Sunny	62°17° (likely 59°15° to 63°17°)	62°17°	0%	5 mph8 km/h from SE, gusts 7 mph11 km/h	46%	22%	1
Sat 6p	Clear	60°16° (likely 56°13° to 60°16°)	60°16°	0%	3 mph5 km/h from SE, gusts 9 mph14 km/h	49%	19%	0
Sat 7p	Clear	56°13° (likely 53°12° to 56°13°)	56°13°	0%	3 mph5 km/h from E, gusts 7 mph11 km/h	59%	18%	0
Sat 8p	Clear	50°10° (likely 50°10° to 53°12°)	49°9°	0%	3 mph5 km/h from E, gusts 8 mph12 km/h	77%	12%	0
Sat 9p	Clear	47°8° (likely 47°8° to 51°11°)	47°8°	0%	2 mph3 km/h from E, gusts 8 mph12 km/h	86%	6%	0
Sat 10p	Clear	45°7° (likely 45°7° to 50°10°)	45°7°	0%	1 mph2 km/h from E, gusts 7 mph12 km/h	89%	19%	0
Sat 11p	Mostly clear	44°7° (likely 44°7° to 50°10°)	44°7°	0%	1 mph2 km/h from E, gusts 6 mph10 km/h	93%	28%	0
Sun 12a	Clear	42°6° (likely 42°6° to 48°9°)	42°6°	0%	1 mph2 km/h from E, gusts 7 mph12 km/h	100%	21%	0
Sun 1a	Clear	41°5° (likely 41°5° to 48°9°)	41°5°	0%	1 mph2 km/h from NE, gusts 6 mph10 km/h	100%	21%	0
Sun 2a	Partly cloudy	41°5° (likely 41°5° to 48°9°)	41°5°	0%	1 mph2 km/h from NE, gusts 6 mph9 km/h	100%	39%	0
Sun 3a	Clear	39°4° (likely 39°4° to 47°8°)	39°4°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	16%	0
Sun 4a	Clear	39°4° (likely 39°4° to 46°8°)	39°4°	0%	1 mph2 km/h from NE, gusts 5 mph8 km/h	100%	13%	0
Sun 5a	Clear	38°3° (likely 38°3° to 46°8°)	38°3°	0%	1 mph2 km/h from N, gusts 5 mph8 km/h	100%	13%	0
Sun 6a	Clear	37°3° (likely 37°3° to 44°7°)	37°3°	0%	1 mph2 km/h from N, gusts 5 mph8 km/h	100%	11%	0
Sun 7a	Sunny	37°3° (likely 37°3° to 43°6°)	37°3°	0%	1 mph2 km/h from N, gusts 5 mph8 km/h	100%	19%	0
Sun 8a	Fog	38°3° (likely 38°3° to 43°6°)	38°3°	0%	1 mph2 km/h from N, gusts 6 mph9 km/h	100%	48%	0
Sun 9a	Partly sunny	42°6° (likely 42°6° to 49°9°)	42°6°	0%	1 mph2 km/h from N, gusts 6 mph10 km/h	100%	44%	1
Sun 10a	Mostly sunny	50°10° (likely 50°10° to 55°13°)	50°10°	0%	1 mph2 km/h from N, gusts 7 mph11 km/h	83%	16%	2
Sun 11a	Mostly sunny	55°13° (likely 55°13° to 60°16°)	55°13°	0%	1 mph2 km/h from NE, gusts 7 mph11 km/h	72%	8%	3
Sun 12p	Mostly sunny	59°15° (likely 59°15° to 62°17°)	59°15°	0%	1 mph2 km/h from E, gusts 6 mph9 km/h	62%	15%	4
Sun 1p	Mostly sunny	62°17° (likely 62°17° to 64°18°)	62°17°	0%	1 mph2 km/h from E, gusts 5 mph8 km/h	54%	20%	4
Sun 2p	Mostly sunny	64°18° (likely 63°17° to 65°18°)	64°18°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	50%	19%	4
Sun 3p	Mostly sunny	65°18° (likely 64°18° to 66°19°)	65°18°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	48%	17%	4
Sun 4p	Sunny	66°19° (likely 64°18° to 66°19°)	66°19°	0%	1 mph2 km/h from SE, gusts 7 mph11 km/h	47%	14%	3
Sun 5p	Sunny	65°18° (likely 63°17° to 65°18°)	65°18°	0%	1 mph2 km/h from SE, gusts 6 mph10 km/h	48%	7%	1
Sun 6p	Clear	62°17° (likely 59°15° to 62°17°)	62°17°	0%	1 mph2 km/h from SE, gusts 5 mph9 km/h	54%	0%	0
Sun 7p	Clear	58°14° (likely 55°13° to 58°14°)	58°14°	0%	1 mph2 km/h from E, gusts 5 mph7 km/h	62%	0%	0
Sun 8p	Clear	52°11° (likely 52°11° to 55°13°)	52°11°	0%	1 mph2 km/h from E, gusts 4 mph6 km/h	77%	0%	0
Sun 9p	Clear	49°9° (likely 49°9° to 53°12°)	49°9°	0%	0 mph0 km/h, gusts 5 mph8 km/h	83%	0%	0
Sun 10p	Clear	47°8° (likely 47°8° to 51°11°)	47°8°	0%	0 mph0 km/h, gusts 5 mph8 km/h	89%	0%	0
Sun 11p	Clear	45°7° (likely 45°7° to 50°10°)	45°7°	0%	0 mph0 km/h, gusts 5 mph8 km/h	96%	1%	0
Mon 12a	Clear	43°6° (likely 43°6° to 48°9°)	43°6°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	1%	0
Mon 1a	Clear	42°6° (likely 42°6° to 47°8°)	42°6°	0%	0 mph0 km/h, gusts 3 mph5 km/h	100%	1%	0
Mon 2a	Clear	42°6° (likely 42°6° to 45°7°)	42°6°	0%	1 mph2 km/h from W, gusts 4 mph6 km/h	100%	4%	0
Mon 3a	Clear	41°5° (likely 41°5° to 44°7°)	41°5°	0%	1 mph2 km/h from W, gusts 4 mph6 km/h	100%	13%	0
Mon 4a	Clear	40°4° (likely 40°4° to 44°7°)	40°4°	0%	1 mph2 km/h from W, gusts 4 mph7 km/h	100%	17%	0
Mon 5a	Mostly clear	39°4° (likely 39°4° to 43°6°)	39°4°	0%	1 mph2 km/h from W, gusts 4 mph7 km/h	100%	20%	0
Mon 6a	Mostly clear	39°4° (likely 39°4° to 43°6°)	39°4°	0%	1 mph2 km/h from NW, gusts 4 mph7 km/h	100%	34%	0
Mon 7a	Fog	38°3° (likely 38°3° to 43°6°)	38°3°	0%	1 mph2 km/h from NW, gusts 5 mph7 km/h	100%	50%	0
Mon 8a	Fog	39°4° (likely 37°3° to 45°7°)	39°4°	0%	1 mph2 km/h from NW, gusts 4 mph7 km/h	96%	45%	0
Mon 9a	Sunny	44°7° (likely 39°4° to 51°11°)	44°7°	0%	1 mph2 km/h from NW, gusts 4 mph6 km/h	93%	25%	1
Mon 10a	Sunny	52°11° (likely 47°8° to 56°13°)	52°11°	0%	1 mph2 km/h from NW, gusts 5 mph8 km/h	74%	19%	2
Mon 11a	Sunny	60°16° (likely 55°13° to 60°16°)	60°16°	0%	2 mph3 km/h from W, gusts 6 mph10 km/h	60%	0%	3
Mon 12p	Sunny	65°18° (likely 61°16° to 65°18°)	65°18°	0%	3 mph5 km/h from NW, gusts 7 mph11 km/h	50%	1%	4
Mon 1p	Sunny	69°21° (likely 65°18° to 69°21°)	69°21°	0%	5 mph8 km/h from NW, gusts 9 mph15 km/h	44%	0%	4
Mon 2p	Sunny	71°22° (likely 67°19° to 71°22°)	71°22°	0%	5 mph8 km/h from NW, gusts 11 mph17 km/h	41%	0%	4

Days ahead

Shaded: typical range for these dates (1991–2020)

Today, Oct 24. Partly sunny. High 64°18°, low 37°3°. Typical 65°18° / 42°6°. Dry. Mostly agree.
1. Afternoon
  noon–6 PM
  Partly sunny, 64°18°
  Dry
2. Evening
  6 PM–midnight
  Clear, 50°10°
  Dry
3. Overnight
  midnight–6 AM
  Clear, 38°3°
  Dry
Official NWS forecast
Today: Mostly sunny, with a high near 64. Southeast wind around 5 mph.
Tonight: Patchy fog after 2am. Mostly clear, with a low around 37. East wind 0 to 3 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
60°16°–64°18°
Low, likely
35°2°–38°3°
Typical high / low
65°18° / 42°6°
Wind
6 mph9 km/h, gusts 13 mph22 km/h
UV peak
4
Tomorrow, Oct 25. Partly sunny. High 66°19°, low 38°3°. Typical 64°18° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Partly sunny, 38°3°
  Dry
2. Afternoon
  noon–6 PM
  Mostly sunny, 66°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 52°11°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 39°4°
  Dry
Official NWS forecast
Day: Patchy frost and patchy fog before 9am. Sunny, with a high near 66. East wind around 1 mph.
Night: Clear, with a low around 38. Southeast wind around 1 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
64°18°–66°19°
Low, likely
38°3°–43°6°
Typical high / low
64°18° / 42°6°
Wind
6 mph9 km/h, gusts 11 mph18 km/h
UV peak
4
Monday, Oct 26. Mostly sunny. High 71°22°, low 47°8°. Typical 64°18° / 41°5°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 39°4°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 71°22°
  Dry
3. Evening
  6 PM–midnight
  Clear, 56°13°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 49°10°
  Dry
Official NWS forecast
Day: Sunny, with a high near 71. Northwest wind 1 to 5 mph.
Night: Mostly clear, with a low around 47.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
68°20°–71°22°
Low, likely
37°3°–47°8°
Typical high / low
64°18° / 41°5°
Wind
7 mph11 km/h, gusts 14 mph23 km/h
UV peak
4
Tuesday, Oct 27. Mostly sunny. High 69°21°, low 47°8°. Typical 64°18° / 41°5°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 49°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 67°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 56°14°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 47°8°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 69.
Night: Mostly clear, with a low around 47.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
65°18°–69°21°
Low, likely
45°7°–52°11°
Typical high / low
64°18° / 41°5°
Wind
8 mph12 km/h, gusts 18 mph28 km/h
UV peak
4
Wednesday, Oct 28. Cloudy. High 66°19°, low 47°8°. Typical 64°18° / 41°5°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 47°9°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 56°13°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 49°9°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 66.
Night: Mostly cloudy, with a low around 47.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
63°17°–66°19°
Low, likely
43°6°–50°10°
Typical high / low
64°18° / 41°5°
Wind
7 mph11 km/h, gusts 15 mph24 km/h
UV peak
4
Thursday, Oct 29. Cloudy. High 71°22°, low 49°9°. Typical 63°17° / 40°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Partly sunny, 48°9°
  Dry
2. Afternoon
  noon–6 PM
  Mostly sunny, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 48°9°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 71.
Night: Mostly clear, with a low around 49.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
67°19°–71°22°
Low, likely
45°7°–49°9°
Typical high / low
63°17° / 40°4°
Wind
8 mph12 km/h, gusts 23 mph37 km/h
UV peak
4
Friday, Oct 30. Mostly sunny. High 75°24°, low 50°10°. Typical 63°17° / 40°4°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 48°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 74°24°
  Dry
3. Evening
  6 PM–midnight
  Clear, 61°16°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 50°10°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 75.
Night: Mostly clear, with a low around 50.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
74°23°–75°24°
Low, likely
44°7°–51°11°
Typical high / low
63°17° / 40°4°
Wind
6 mph10 km/h, gusts 26 mph42 km/h
UV peak
4
Saturday, Oct 31. Cloudy. High 72°22°, low 50°10°. Typical 62°17° / 40°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Mostly sunny, 49°9°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 73°23°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 61°16°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 56°13°
  Dry
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
70°21°–74°23°
Low, likely
44°7°–56°13°
Typical high / low
62°17° / 40°4°
Wind
7 mph10 km/h, gusts 27 mph44 km/h
UV peak
4
Sunday, Nov 1. Drizzle. High 70°21°, low 55°13°. Typical 62°17° / 40°4°. Rain 0.03 in0.8 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 57°14°
  Dry
2. Afternoon
  noon–6 PM
  Partly sunny, 69°21°
  30% chance
3. Evening
  6 PM–midnight
  Drizzle, 65°18°
  30% chance · 0.01 in0.3 mm
4. Overnight
  midnight–6 AM
  Drizzle, 63°17°
  20% chance · 0.04 in1 mm
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
64°18°–74°23°
Low, likely
53°12°–57°14°
Typical high / low
62°17° / 40°4°
Wind
10 mph16 km/h, gusts 24 mph38 km/h
UV peak
2
Monday, Nov 2. Drizzle. High 72°22°, low 60°16°. Typical 62°17° / 39°4°. Rain 0.37 in9.4 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Drizzle, 64°18°
  20% chance · 0.01 in0.3 mm
2. Afternoon
  noon–6 PM
  Drizzle, 72°22°
  Dry
3. Evening
  6 PM–midnight
  Drizzle, 65°18°
  Dry
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
63°17°–78°26°
Low, likely
55°13°–66°19°
Typical high / low
62°17° / 39°4°
Wind
17 mph28 km/h, gusts 36 mph58 km/h

10 days15 days30 days

The outlook

Today
Dry, high 64°, low 37°.
Tomorrow
Dry, high 66°, low 38°.
Monday
Dry, high 71°, low 47°, warming up.
Rest of week
Mostly dry, highs 66–75°.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (LWX) (opens in a new tab)

What changed since yesterday

No meaningful changes from yesterday’s forecast.

Radar

Radar data: NOAA MRMS, rendered by forecast.blue

Radar loads when scrolled into view

Full-screen radar

Rivers

NOAA river gauges within 25 mi

Willow Springs Branch near Centreville (Hampton Forest Sec 4 Regional Pond)

2.5 mi

Level: 367 ft

Reading from Sat 12:25 PM · NWS gauge page

Sideburn Branch at Woodglen Lake

4.0 mi

Level: 334 ft

Reading from Sat 2:25 PM · NWS gauge page

Unnamed Tributary at Lake Barton in Burke

4.3 mi

Below flood stage

Level: 319 ft

Reading from Sat 10:40 AM · NWS gauge page

Unnamed Tributary near Fairfax Center

4.3 mi

Level: 383 ft

Reading from Sat 1:05 PM · NWS gauge page

For your home

What this week’s weather means for heating, cooling, pipes and fresh air.

Heating this week

About 66% less heating than a typical week.

This week 30Typical 88

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F: 25
h below 17°F: 0
h below 5°F: 0

47, 17 and 5°F are the test points heat pumps are rated at. About 18 hours are near freezing and damp, when outdoor units defrost more often.

Comfort

Dry air outside (dew point 39°F).

Open the windows?

Today, 4:00 PM–6:00 PM

Good stretch to open the windows.

Is this typical?

Washington Dulles International Airport · official normals 1991–2020 · records 1960–2026

Oct 24, today vs a typical year

Today’s expected high is about typical for the date.

Last 7 days vs normal

On average 2°1° colder than normal (daily mean temperature).

−6°−3°SunOct 18
−3°−2°MonOct 19
+2°+1°TueOct 20
±0°WedOct 21
−2°−1°ThuOct 22
−1°FriOct 23
—SatOct 24

Union Mill weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 51 min; Losing 2 min 16 s a day; shortest Dec 21, 1 h 24 min less
Golden hour: 5:41–6:35 PM; Morning 7:11–8:04 AM
Blue hour: 6:35–6:45 PM; Morning 7:00–7:11 AM; first light 7:00 AM

Stars tonight? Fair

Mostly clear 6:45–11 PM, but the moon is 99% lit and up.

Moon

Waxing gibbous

98% lit · growing

Today: sets 5:40 AM · rises 5:15 PM
Full moon: Oct 26
New moon: Nov 9

Looking west from Union Mill. The highest point on the skyline is about 3,900 ft, 56 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.