Observed 10:00 AM EDT at KIAD

Sully Square, VA weather

Sunny and 50°10°.

Mostly agree

Now 50°10°

Sunny

Wind: 3 mph5 km/h; From the northwest. Light through 10 PM
Dew point: 43°6°; Comfortable
UV index: 3Moderate; Moderate 11 AM–5 PM · peak 4
Air quality: 55Moderate; Main pollutant: PM2.5 (fine particles)
Pressure: 30.56 inHg1035 hPa; Steady over the last 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

Above 60°16° today by 1 PM
High 63°17° today at 3 PM
Below 50°10° tonight after 9 PM
Fog tonight midnight–1 AM
Fog tomorrow 9–10 AM

This morningUp to 54°12° by 11 AM · Clear
This afternoonUp to 63°17° by 3 PM · Clear
TonightDown to 37°3° by 5 AM · Clear
Tomorrow morningUp to 55°13° by 11 AM · Clear
Tomorrow afternoonUp to 66°19° by 3 PM · Clear
Tomorrow nightDown to 40°4° by 5 AM · Clear
Monday morningUp to 44°7° by 9 AM · Partly cloudy

Hourly forecast, next 48 hours, in the place's local time
Hour	Conditions	Temperature	Feels like	Precipitation	Wind	Humidity	Cloud cover	UV index
Sat 10a	Sunny	48°9° (likely 48°9° to 51°11°)	48°9°	0%	1 mph2 km/h from NE, gusts 4 mph7 km/h	77%	3%	2
Sat 11a	Sunny	54°12° (likely 54°12° to 56°13°)	54°12°	0%	2 mph3 km/h from E, gusts 9 mph14 km/h	66%	1%	3
Sat 12p	Sunny	58°14° (likely 57°14° to 59°15°)	58°14°	0%	3 mph5 km/h from E, gusts 10 mph16 km/h	55%	10%	4
Sat 1p	Sunny	61°16° (likely 59°15° to 61°16°)	61°16°	0%	3 mph5 km/h from E, gusts 9 mph14 km/h	48%	11%	4
Sat 2p	Sunny	62°17° (likely 60°16° to 62°17°)	62°17°	0%	3 mph5 km/h from E, gusts 9 mph15 km/h	44%	13%	4
Sat 3p	Sunny	63°17° (likely 60°16° to 63°17°)	63°17°	0%	3 mph5 km/h from E, gusts 8 mph13 km/h	43%	17%	4
Sat 4p	Mostly sunny	63°17° (likely 60°16° to 63°17°)	63°17°	0%	3 mph5 km/h from E, gusts 8 mph13 km/h	44%	18%	3
Sat 5p	Partly sunny	62°17° (likely 59°15° to 62°17°)	62°17°	0%	3 mph5 km/h from E, gusts 8 mph13 km/h	48%	33%	1
Sat 6p	Partly cloudy	58°14° (likely 56°13° to 59°15°)	58°14°	0%	3 mph5 km/h from E, gusts 8 mph13 km/h	55%	27%	0
Sat 7p	Clear	53°12° (likely 52°11° to 55°13°)	53°12°	0%	3 mph5 km/h from E, gusts 8 mph13 km/h	69%	18%	0
Sat 8p	Clear	50°10° (likely 50°10° to 52°11°)	49°9°	0%	3 mph5 km/h from E, gusts 9 mph14 km/h	77%	12%	0
Sat 9p	Clear	47°8° (likely 47°8° to 50°10°)	47°8°	0%	2 mph3 km/h from E, gusts 8 mph12 km/h	86%	0%	0
Sat 10p	Clear	45°7° (likely 45°7° to 49°9°)	45°7°	0%	1 mph2 km/h from E, gusts 7 mph11 km/h	93%	1%	0
Sat 11p	Clear	42°6° (likely 42°6° to 48°9°)	42°6°	0%	1 mph2 km/h from E, gusts 7 mph11 km/h	100%	17%	0
Sun 12a	Fog	41°5° (likely 41°5° to 48°9°)	41°5°	0%	1 mph2 km/h from E, gusts 7 mph11 km/h	100%	23%	0
Sun 1a	Clear	40°4° (likely 40°4° to 48°9°)	40°4°	0%	0 mph0 km/h, gusts 7 mph11 km/h	100%	20%	0
Sun 2a	Clear	40°4° (likely 40°4° to 46°8°)	40°4°	0%	0 mph0 km/h, gusts 7 mph11 km/h	100%	17%	0
Sun 3a	Clear	38°3° (likely 38°3° to 46°8°)	38°3°	0%	0 mph0 km/h, gusts 6 mph10 km/h	100%	12%	0
Sun 4a	Clear	38°3° (likely 38°3° to 43°6°)	38°3°	0%	0 mph0 km/h, gusts 3 mph4 km/h	100%	12%	0
Sun 5a	Clear	37°3° (likely 37°3° to 42°6°)	37°3°	0%	1 mph2 km/h from N, gusts 4 mph6 km/h	100%	3%	0
Sun 6a	Clear	37°3° (likely 37°3° to 42°6°)	37°3°	0%	1 mph2 km/h from N, gusts 4 mph6 km/h	100%	5%	0
Sun 7a	Sunny	36°2° (likely 36°2° to 41°5°)	36°2°	0%	1 mph2 km/h from N, gusts 4 mph6 km/h	100%	7%	0
Sun 8a	Sunny	37°3° (likely 37°3° to 41°5°)	37°3°	0%	1 mph2 km/h from N, gusts 4 mph7 km/h	100%	18%	0
Sun 9a	Fog	42°6° (likely 42°6° to 46°8°)	42°6°	0%	1 mph2 km/h from N, gusts 4 mph7 km/h	96%	27%	1
Sun 10a	Sunny	49°9° (likely 49°9° to 53°12°)	49°9°	0%	0 mph0 km/h, gusts 7 mph12 km/h	80%	2%	2
Sun 11a	Sunny	55°13° (likely 55°13° to 58°14°)	55°13°	0%	0 mph0 km/h, gusts 5 mph8 km/h	69%	4%	3
Sun 12p	Sunny	59°15° (likely 59°15° to 61°16°)	59°15°	0%	1 mph2 km/h from NE, gusts 6 mph10 km/h	60%	6%	4
Sun 1p	Sunny	62°17° (likely 62°17° to 63°17°)	62°17°	0%	0 mph0 km/h, gusts 5 mph8 km/h	52%	8%	4
Sun 2p	Mostly sunny	65°18° (likely 63°17° to 65°18°)	65°18°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	46%	10%	4
Sun 3p	Sunny	66°19° (likely 64°18° to 66°19°)	66°19°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	45%	6%	4
Sun 4p	Sunny	66°19° (likely 64°18° to 66°19°)	66°19°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	45%	14%	3
Sun 5p	Sunny	65°18° (likely 63°17° to 65°18°)	65°18°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	46%	20%	1
Sun 6p	Clear	61°16° (likely 59°15° to 62°17°)	61°16°	0%	1 mph2 km/h from S, gusts 5 mph9 km/h	53%	0%	0
Sun 7p	Clear	56°13° (likely 54°12° to 57°14°)	56°13°	0%	0 mph0 km/h, gusts 6 mph10 km/h	66%	0%	0
Sun 8p	Clear	52°11° (likely 52°11° to 55°13°)	52°11°	0%	1 mph2 km/h from SE, gusts 5 mph8 km/h	83%	1%	0
Sun 9p	Clear	49°9° (likely 49°9° to 54°12°)	49°9°	0%	0 mph0 km/h, gusts 5 mph8 km/h	93%	0%	0
Sun 10p	Clear	47°8° (likely 47°8° to 51°11°)	47°8°	0%	0 mph0 km/h, gusts 6 mph10 km/h	96%	0%	0
Sun 11p	Clear	45°7° (likely 45°7° to 50°10°)	45°7°	0%	0 mph0 km/h, gusts 6 mph9 km/h	100%	0%	0
Mon 12a	Clear	44°7° (likely 44°7° to 48°9°)	44°7°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	0%	0
Mon 1a	Clear	43°6° (likely 42°6° to 47°8°)	43°6°	0%	1 mph2 km/h from W, gusts 4 mph6 km/h	100%	0%	0
Mon 2a	Clear	42°6° (likely 41°5° to 46°8°)	42°6°	0%	1 mph2 km/h from W, gusts 5 mph7 km/h	100%	13%	0
Mon 3a	Clear	41°5° (likely 39°4° to 45°7°)	41°5°	0%	1 mph2 km/h from W, gusts 5 mph8 km/h	100%	14%	0
Mon 4a	Clear	41°5° (likely 38°3° to 45°7°)	41°5°	0%	1 mph2 km/h from W, gusts 5 mph9 km/h	100%	16%	0
Mon 5a	Clear	40°4° (likely 38°3° to 44°7°)	40°4°	0%	1 mph2 km/h from W, gusts 5 mph9 km/h	100%	16%	0
Mon 6a	Mostly clear	38°3° (likely 37°3° to 43°6°)	38°3°	0%	1 mph2 km/h from W, gusts 5 mph8 km/h	100%	28%	0
Mon 7a	Mostly clear	37°3° (likely 36°2° to 43°6°)	37°3°	0%	2 mph3 km/h from W, gusts 5 mph8 km/h	100%	27%	0
Mon 8a	Sunny	39°4° (likely 36°2° to 43°6°)	39°4°	0%	2 mph3 km/h from W, gusts 4 mph7 km/h	100%	26%	0
Mon 9a	Sunny	44°7° (likely 39°4° to 50°10°)	44°7°	0%	2 mph3 km/h from W, gusts 5 mph7 km/h	89%	30%	1

Days ahead

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

Today, Oct 24. Mostly sunny. High 63°17°, low 36°2°. Typical 65°18° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 54°12°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 50°10°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 37°3°
  Dry
Official NWS forecast
Today: Sunny, with a high near 63. East wind around 3 mph.
Tonight: Patchy fog between 11pm and 5am, then patchy frost and patchy fog. Mostly clear, with a low around 36. Northeast wind 0 to 3 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
60°16°–63°17°
Low, likely
36°2°–39°4°
Typical high / low
65°18° / 42°6°
Wind
7 mph11 km/h, gusts 13 mph21 km/h
UV peak
4
Tomorrow, Oct 25. Fog. High 66°19°, low 37°3°. Typical 64°18° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Fog, 37°3°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 66°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 52°11°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 40°4°
  Dry
Official NWS forecast
Day: Patchy frost and patchy fog before 10am. Sunny, with a high near 66. Northeast wind around 1 mph.
Night: Clear, with a low around 37. South wind around 1 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
64°18°–66°19°
Low, likely
37°3°–41°5°
Typical high / low
64°18° / 42°6°
Wind
7 mph11 km/h
UV peak
4
Monday, Oct 26. Mostly sunny. High 69°21°, low 48°9°. Typical 64°18° / 41°5°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 39°4°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 55°13°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 48°9°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Patchy frost between 7am and 8am. Sunny, with a high near 69. West wind 1 to 6 mph.
Night: Mostly clear, with a low around 48.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
67°19°–69°21°
Low, likely
36°2°–48°9°
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 67°19°, low 44°7°. Typical 64°18° / 41°5°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 47°8°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 67°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 56°13°
  Dry
4. Overnight
  midnight–6 AM
  Partly cloudy, 47°8°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 67.
Night: Mostly clear, with a low around 44.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
65°18°–70°21°
Low, likely
44°7°–49°9°
Typical high / low
64°18° / 41°5°
Wind
8 mph12 km/h, gusts 18 mph29 km/h
UV peak
4
Wednesday, Oct 28. Cloudy. High 65°18°, low 46°8°. Typical 64°18° / 41°5°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Mostly sunny, 46°8°
  Dry
2. Afternoon
  noon–6 PM
  Mostly sunny, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 55°13°
  Dry
4. Overnight
  midnight–6 AM
  Mostly clear, 47°8°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 65.
Night: Mostly cloudy, with a low around 46.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
63°17°–66°19°
Low, likely
43°6°–47°8°
Typical high / low
64°18° / 41°5°
Wind
7 mph11 km/h, gusts 16 mph25 km/h
UV peak
4
Thursday, Oct 29. Partly sunny. High 70°21°, low 49°9°. Typical 63°17° / 40°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 47°8°
  Dry
2. Afternoon
  noon–6 PM
  Mostly sunny, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 57°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 70.
Night: Mostly clear, with a low around 49.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
66°19°–70°21°
Low, likely
45°7°–49°9°
Typical high / low
63°17° / 40°4°
Wind
7 mph11 km/h, gusts 24 mph38 km/h
UV peak
4
Friday, Oct 30. Mostly sunny. High 73°23°, low 48°9°. Typical 63°17° / 40°4°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 46°8°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 74°23°
  Dry
3. Evening
  6 PM–midnight
  Clear, 61°16°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 47°8°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 73.
Night: Mostly clear, with a low around 48.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
73°23°–75°24°
Low, likely
43°6°–49°9°
Typical high / low
63°17° / 40°4°
Wind
10 mph16 km/h, gusts 26 mph42 km/h
UV peak
4
Saturday, Oct 31. Cloudy. High 69°21°, low 47°8°. Typical 62°17° / 40°4°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 46°8°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 60°16°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 51°11°
  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
59°15°–75°24°
Low, likely
44°7°–50°10°
Typical high / low
62°17° / 40°4°
Wind
10 mph17 km/h, gusts 28 mph44 km/h
UV peak
2
Sunday, Nov 1. Cloudy. High 68°20°, low 51°11°. Typical 62°17° / 40°4°. Rain 0.02 in0.5 mm, 20% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 50°10°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 67°20°
  20% chance
3. Evening
  6 PM–midnight
  Cloudy, 59°15°
  30% chance
4. Overnight
  midnight–6 AM
  Cloudy, 55°13°
  30% chance · 0.01 in0.3 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
57°14°–73°23°
Low, likely
44°7°–54°12°
Typical high / low
62°17° / 40°4°
Wind
9 mph15 km/h, gusts 22 mph36 km/h
UV peak
3
Monday, Nov 2. Cloudy. High 68°20°, low 54°12°. Typical 62°17° / 39°4°. Rain 0.08 in2 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 58°15°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 69°20°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 60°16°
  20% chance
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
56°13°–76°24°
Low, likely
46°8°–59°15°
Typical high / low
62°17° / 39°4°
Wind
8 mph13 km/h, gusts 17 mph27 km/h
UV peak
2

10 days15 days30 days

The outlook

Today
Dry, high 63°, low 36°.
Tomorrow
Dry, high 66°, low 37°, warming up.
Monday
Dry, high 69°, low 48°, warming up.
Rest of week
Mostly dry, highs 65–73°.

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

Horsepen Run above Oak Hill (West Ox Road Regional Pond)

1.5 mi

Level: 322 ft

Reading from Sat 6:45 AM · NWS gauge page

Unnamed Tributary at Dulles Station near Herndon

2.3 mi

Level: 307 ft

Reading from Sat 6 AM · NWS gauge page

Flatlick Branch at Chantilly

2.8 mi

Below flood stage

Level: 1.1 ft
Flow: 18 cfs

Reading from Sat 10 AM · NWS gauge page

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

6.2 mi

Level: 367 ft

Reading from Sat 6:25 AM · NWS gauge page

For your home

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

Heating this week

About 65% less heating than a typical week.

This week 31Typical 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 43°F).

Open the windows?

Today, 1:00 PM–5:00 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 2°1° colder than typical.

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

Sully Square weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 50 min; Losing 2 min 16 s a day; shortest Dec 21, 1 h 24 min less
Golden hour: 5:41–6:35 PM; Morning 7:11–8:05 AM
Blue hour: 6:35–6:45 PM; Morning 7:01–7:11 AM; first light 7:01 AM

Stars tonight? Fair

Mostly clear 7 PM–7:02 AM, but the moon is 99% lit and up.

Moon

Waxing gibbous

97% lit · growing

Today: sets 5:41 AM · rises 5:15 PM
Full moon: Oct 26
New moon: Nov 9

Looking west from Sully Square. The highest point on the skyline is about 3,900 ft, 58 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.