Frost Advisory
Starts in 1 h 36 min
When
From midnight tonight to 9 AM EDT Saturday.
Where
Portions of central, northern, and southern New Jersey and southeast Pennsylvania.
Issued for this forecast zone · National Weather Service Mount Holly NJ
What, impacts and precautionsHide details
What
Temperatures as low as 33 degrees will result in frost formation.
Impacts
Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered.
Precautionary actions
Take steps now to protect tender plants from the cold.
Areas: Middlesex; Western Monmouth; Mercer; Salem; Gloucester; Camden; Northwestern Burlington; Ocean; Cumberland; Atlantic; Southeastern Burlington; Delaware; Philadelphia; Eastern Chester; Eastern Montgomery; Lower Bucks
See it on weather.gov (opens in a new tab)

Observed 9:54 PM EDT at KPNE

Croydon, PA weather

Clear and 46°8°.

Forecasts agree

Now 46°8°

Clear

Wind: Calm; Up to 5 mph8 km/h through 10 AM
Dew point: 35°2°; Comfortable
UV tomorrow: 4Moderate; Moderate 11 AM–4 PM · peak 4
Air quality: 43Good; PM2.5 (fine particles) · tomorrow moderate
Pressure: 30.47 inHg1032 hPa; Rising slowly · +0.04 inHg+1.2 hPa in 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

11°6° cooler than this time yesterday (57°14° then, 46°8° now)

Good hours for

Low 36°2° tomorrow at 6 AM
Above 50°10° tomorrow by 10 AM
High 64°18° tomorrow at 4 PM
Drops 12°7° tomorrow night 6–9 PM (61°16° → 49°9°)
Below 50°10° tomorrow night after 8 PM

TonightDown to 37°3° by 5 AM · Clear
Tomorrow morningUp to 56°13° by 11 AM · Partly cloudy
Tomorrow afternoonUp to 64°18° by 4 PM · Clear
Tomorrow nightDown to 36°2° by 5 AM · Clear
Sunday morningUp to 56°13° by 11 AM · Clear
Sunday afternoonUp to 66°19° by 3 PM · Clear
Sunday nightDown to 49°9° by 9 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
Fri 10p	Mostly clear	43°6° (likely 43°6° to 47°8°)	43°6°	0%	0 mph0 km/h, gusts 4 mph6 km/h	79%	68%	0
Fri 11p	Partly cloudy	42°6° (likely 42°6° to 46°8°)	42°6°	0%	0 mph0 km/h, gusts 4 mph7 km/h	82%	46%	0
Sat 12a	Mostly clear	40°4° (likely 40°4° to 45°7°)	40°4°	0%	0 mph0 km/h, gusts 3 mph5 km/h	89%	14%	0
Sat 1a	Clear	39°4° (likely 39°4° to 45°7°)	39°4°	0%	0 mph0 km/h, gusts 3 mph5 km/h	89%	3%	0
Sat 2a	Clear	39°4° (likely 39°4° to 44°7°)	39°4°	0%	0 mph0 km/h, gusts 3 mph5 km/h	89%	0%	0
Sat 3a	Clear	38°3° (likely 38°3° to 43°6°)	38°3°	0%	0 mph0 km/h, gusts 4 mph7 km/h	92%	2%	0
Sat 4a	Clear	38°3° (likely 38°3° to 42°6°)	38°3°	0%	0 mph0 km/h, gusts 4 mph7 km/h	92%	13%	0
Sat 5a	Partly cloudy	37°3° (likely 37°3° to 41°5°)	37°3°	0%	5 mph8 km/h from N, gusts 5 mph7 km/h	92%	47%	0
Sat 6a	Partly cloudy	36°2° (likely 36°2° to 40°4°)	36°2°	0%	0 mph0 km/h, gusts 5 mph7 km/h	96%	64%	0
Sat 7a	Mostly sunny	36°2° (likely 36°2° to 40°4°)	36°2°	0%	0 mph0 km/h, gusts 6 mph9 km/h	96%	61%	0
Sat 8a	Partly sunny	39°4° (likely 38°3° to 41°5°)	37°3°	0%	5 mph8 km/h from N, gusts 5 mph8 km/h	85%	32%	0
Sat 9a	Mostly sunny	44°7° (likely 43°6° to 45°7°)	42°6°	0%	5 mph8 km/h from N, gusts 6 mph9 km/h	76%	29%	1
Sat 10a	Mostly sunny	51°11° (likely 50°10° to 52°11°)	51°11°	0%	5 mph8 km/h from N, gusts 6 mph9 km/h	59%	26%	2
Sat 11a	Sunny	56°13° (likely 54°12° to 57°14°)	56°13°	0%	5 mph8 km/h from NE, gusts 5 mph7 km/h	49%	6%	3
Sat 12p	Mostly sunny	59°15° (likely 57°14° to 60°16°)	59°15°	0%	0 mph0 km/h, gusts 3 mph5 km/h	45%	10%	4
Sat 1p	Sunny	62°17° (likely 59°15° to 62°17°)	62°17°	0%	0 mph0 km/h, gusts 4 mph7 km/h	39%	9%	4
Sat 2p	Sunny	63°17° (likely 60°16° to 63°17°)	63°17°	0%	0 mph0 km/h, gusts 4 mph6 km/h	35%	10%	4
Sat 3p	Sunny	63°17° (likely 61°16° to 64°18°)	63°17°	0%	0 mph0 km/h, gusts 4 mph6 km/h	35%	7%	3
Sat 4p	Sunny	64°18° (likely 61°16° to 64°18°)	64°18°	0%	0 mph0 km/h, gusts 4 mph6 km/h	35%	4%	2
Sat 5p	Sunny	63°17° (likely 60°16° to 63°17°)	63°17°	0%	0 mph0 km/h, gusts 4 mph6 km/h	35%	0%	1
Sat 6p	Clear	61°16° (likely 56°13° to 61°16°)	61°16°	0%	0 mph0 km/h, gusts 4 mph6 km/h	39%	0%	0
Sat 7p	Clear	57°14° (likely 53°12° to 57°14°)	57°14°	0%	0 mph0 km/h, gusts 2 mph3 km/h	47%	0%	0
Sat 8p	Clear	49°9° (likely 49°9° to 53°12°)	49°9°	0%	0 mph0 km/h, gusts 3 mph5 km/h	66%	0%	0
Sat 9p	Clear	46°8° (likely 46°8° to 51°11°)	46°8°	0%	0 mph0 km/h, gusts 3 mph4 km/h	79%	0%	0
Sat 10p	Clear	44°7° (likely 44°7° to 49°9°)	44°7°	0%	0 mph0 km/h, gusts 6 mph9 km/h	86%	0%	0
Sat 11p	Clear	42°6° (likely 42°6° to 47°8°)	42°6°	0%	0 mph0 km/h, gusts 6 mph9 km/h	96%	0%	0
Sun 12a	Clear	41°5° (likely 41°5° to 46°8°)	41°5°	0%	0 mph0 km/h, gusts 5 mph7 km/h	100%	0%	0
Sun 1a	Clear	40°4° (likely 40°4° to 45°7°)	40°4°	0%	0 mph0 km/h, gusts 4 mph6 km/h	100%	0%	0
Sun 2a	Clear	39°4° (likely 39°4° to 45°7°)	39°4°	0%	0 mph0 km/h, gusts 4 mph6 km/h	100%	1%	0
Sun 3a	Clear	38°3° (likely 38°3° to 44°7°)	38°3°	0%	0 mph0 km/h, gusts 3 mph5 km/h	100%	2%	0
Sun 4a	Clear	37°3° (likely 37°3° to 43°6°)	37°3°	0%	0 mph0 km/h, gusts 3 mph5 km/h	100%	4%	0
Sun 5a	Clear	36°2° (likely 36°2° to 42°6°)	36°2°	0%	0 mph0 km/h, gusts 3 mph5 km/h	100%	7%	0
Sun 6a	Clear	36°2° (likely 36°2° to 41°5°)	36°2°	0%	0 mph0 km/h, gusts 4 mph6 km/h	100%	10%	0
Sun 7a	Mostly sunny	36°2° (likely 36°2° to 40°4°)	36°2°	0%	0 mph0 km/h, gusts 4 mph6 km/h	100%	10%	0
Sun 8a	Mostly sunny	38°3° (likely 38°3° to 40°4°)	38°3°	0%	0 mph0 km/h, gusts 3 mph4 km/h	100%	10%	0
Sun 9a	Sunny	43°6° (likely 43°6° to 45°7°)	43°6°	0%	0 mph0 km/h, gusts 3 mph5 km/h	89%	0%	1
Sun 10a	Sunny	50°10° (likely 50°10° to 52°11°)	50°10°	0%	0 mph0 km/h, gusts 5 mph8 km/h	71%	1%	2
Sun 11a	Sunny	56°13° (likely 56°13° to 58°14°)	56°13°	0%	0 mph0 km/h, gusts 5 mph8 km/h	62%	2%	3
Sun 12p	Sunny	60°16° (likely 59°15° to 63°17°)	60°16°	0%	0 mph0 km/h, gusts 7 mph11 km/h	51%	4%	4
Sun 1p	Sunny	63°17° (likely 61°16° to 64°18°)	63°17°	0%	0 mph0 km/h, gusts 6 mph9 km/h	43%	4%	4
Sun 2p	Sunny	64°18° (likely 62°17° to 66°19°)	64°18°	0%	0 mph0 km/h, gusts 6 mph9 km/h	40%	3%	4
Sun 3p	Sunny	66°19° (likely 62°17° to 66°19°)	66°19°	0%	0 mph0 km/h, gusts 6 mph10 km/h	37%	1%	3
Sun 4p	Sunny	66°19° (likely 63°17° to 66°19°)	66°19°	0%	0 mph0 km/h, gusts 6 mph10 km/h	37%	0%	2
Sun 5p	Sunny	64°18° (likely 62°17° to 65°18°)	64°18°	0%	0 mph0 km/h, gusts 6 mph9 km/h	41%	0%	1
Sun 6p	Clear	61°16° (likely 58°14° to 61°16°)	61°16°	0%	0 mph0 km/h, gusts 4 mph7 km/h	48%	0%	0
Sun 7p	Clear	56°13° (likely 53°12° to 57°14°)	56°13°	0%	0 mph0 km/h, gusts 5 mph8 km/h	59%	0%	0
Sun 8p	Clear	52°11° (likely 50°10° to 55°13°)	52°11°	0%	0 mph0 km/h, gusts 4 mph7 km/h	71%	0%	0
Sun 9p	Clear	49°9° (likely 46°8° to 56°13°)	49°9°	0%	0 mph0 km/h, gusts 2 mph3 km/h	80%	0%	0

Days ahead

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

Today, Oct 23. Partly sunny. High 61°16°, low 36°2°. Typical 63°17° / 43°6°. Dry. Forecasts agree.
1. Evening
  6 PM–midnight
  Partly cloudy, 42°6°
  Dry
2. Overnight
  midnight–6 AM
  Clear, 37°3°
  Dry
Official NWS forecast
Tonight: Areas of frost after midnight. Partly cloudy, with a low around 36. Northeast wind 0 to 5 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
61°16°–62°17°
Low, likely
36°2°–46°8°
Typical high / low
63°17° / 43°6°
Wind
11 mph18 km/h, gusts 24 mph38 km/h
UV peak
4
Tomorrow, Oct 24. Mostly sunny. High 64°18°, low 36°2°. Typical 62°17° / 43°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Mostly sunny, 39°4°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Clear, 49°9°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 36°2°
  Dry
Official NWS forecast
Day: Areas of frost before 10am. Sunny, with a high near 64. East wind 0 to 5 mph.
Night: Patchy frost after 10pm. Clear, with a low around 36. Southeast wind around 0 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
61°16°–64°18°
Low, likely
36°2°–40°4°
Typical high / low
62°17° / 43°6°
Wind
5 mph8 km/h
UV peak
4
Sunday, Oct 25. Sunny. High 66°19°, low 40°4°. Typical 62°17° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 38°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, 43°6°
  Dry
Official NWS forecast
Day: Patchy frost before 9am. Sunny, with a high near 66. Northwest wind around 0 mph.
Night: Clear, with a low around 40. Northwest wind around 0 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
63°17°–66°19°
Low, likely
37°3°–40°4°
Typical high / low
62°17° / 42°6°
Wind
5 mph7 km/h
UV peak
4
Monday, Oct 26. Sunny. High 69°21°, low 49°9°. Typical 62°17° / 42°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 43°6°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 69°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 52°11°
  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 49.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
68°20°–70°21°
Low, likely
37°3°–49°9°
Typical high / low
62°17° / 42°6°
Wind
7 mph12 km/h, gusts 17 mph28 km/h
UV peak
4
Tuesday, Oct 27. Mostly sunny. High 66°19°, low 44°7°. Typical 61°16° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 50°10°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 53°11°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 43°6°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 66.
Night: Partly cloudy, with a low around 44.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
62°17°–66°19°
Low, likely
44°7°–50°10°
Typical high / low
61°16° / 42°6°
Wind
9 mph15 km/h, gusts 24 mph39 km/h
UV peak
4
Wednesday, Oct 28. Cloudy. High 64°18°, low 47°8°. Typical 61°16° / 41°5°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 42°6°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 62°17°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 54°12°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 47°8°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 64.
Night: Mostly cloudy, with a low around 47.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
60°16°–64°18°
Low, likely
39°4°–47°8°
Typical high / low
61°16° / 41°5°
Wind
9 mph14 km/h, gusts 20 mph32 km/h
UV peak
4
Thursday, Oct 29. Partly sunny. High 69°21°, low 51°11°. Typical 61°16° / 41°5°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 47°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 67°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°15°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 51°11°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 69.
Night: Partly cloudy, with a low around 51.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
64°18°–70°21°
Low, likely
46°8°–51°11°
Typical high / low
61°16° / 41°5°
Wind
8 mph13 km/h, gusts 28 mph45 km/h
UV peak
4
Friday, Oct 30. Sunny. High 70°21°, low 50°10°. Typical 60°16° / 41°5°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 51°10°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 69°21°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°15°
  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.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
65°18°–73°23°
Low, likely
47°8°–52°11°
Typical high / low
60°16° / 41°5°
Wind
8 mph13 km/h, gusts 23 mph37 km/h
UV peak
4
Saturday, Oct 31. Mostly sunny. High 68°20°, low 47°8°. Typical 60°16° / 40°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 47°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 48°9°
  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
66°19°–70°21°
Low, likely
39°4°–55°13°
Typical high / low
60°16° / 40°4°
Wind
10 mph17 km/h, gusts 23 mph37 km/h
UV peak
4
Sunday, Nov 1. Cloudy. High 67°19°, low 48°9°. Typical 60°16° / 40°4°. Rain 0.01 in0.3 mm, 20% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 48°9°
  Dry
2. Afternoon
  noon–6 PM
  Partly sunny, 66°19°
  20% chance
3. Evening
  6 PM–midnight
  Partly cloudy, 58°15°
  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
60°16°–72°22°
Low, likely
46°8°–51°11°
Typical high / low
60°16° / 40°4°
Wind
11 mph18 km/h, gusts 20 mph32 km/h
UV peak
4

10 days15 days30 days

The outlook

Today
Dry, high 61°, low 36°.
Tomorrow
Dry, high 64°, low 36°, warming up.
Sunday
Dry, high 66°, low 40°.
Rest of week
Mostly dry, highs 64–70°.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (PHI) (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

Delaware River at Burlington (IN MLLW)

1.5 mi

Below flood stage

Level: 2.3 ft

Forecast peak 9.1 ft Sat 1 AM

Reading from Fri 8:36 PM · NWS gauge page

Neshaminy Creek near Langhorne

6.6 mi

Below flood stage

Level: 1.1 ft
Flow: 123 cfs

Forecast peak 1.1 ft Sat 2 AM

Reading from Fri 8:15 PM · NWS gauge page

Delaware River at Trenton

11 mi

Below flood stage

Level: 8.7 ft
Flow: 4,620 cfs

Forecast peak 8.6 ft Sat 2 AM

Reading from Fri 8:15 PM · NWS gauge page

Assunpink Creek at Trenton

12 mi

Below flood stage

Level: 2.9 ft
Flow: 71 cfs

Forecast peak 2.9 ft Sat 2 AM

Reading from Fri 8:15 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 32Typical 92

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F: 24
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 20 hours are near freezing and damp, when outdoor units defrost more often.

Comfort

Dry air outside (dew point 35°F).

Open the windows?

Sat, 1:00 PM–6:00 PM

Good stretch to open the windows.

Is this typical?

Trenton-Mercer Airport · official normals 1991–2020 · records 1865–2026

Oct 23, today vs a typical year

Today’s expected high is 2°1° colder than typical.

Last 7 days vs normal

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

−7°−4°SunOct 18
−3°−2°MonOct 19
+2°+1°TueOct 20
+2°+1°WedOct 21
+1°ThuOct 22
—FriOct 23
—SatOct 24

Croydon weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 50 min; Losing 2 min 25 s a day; shortest Dec 21, 1 h 30 min less
Golden hour: 5:30–6:25 PM; Morning 7:01–7:56 AM
Blue hour: 6:25–6:36 PM; Morning 6:51–7:01 AM; first light 6:51 AM

Stars tonight? Fair

Mostly clear 12–5 AM, but the moon is 95% lit and up.

Moon

Waxing gibbous

95% lit · growing

Today: sets 4:23 AM · rises 4:39 PM
Full moon: Oct 26
New moon: Nov 9

Looking north from Croydon. The highest point on the skyline is about 4,200 ft, 65 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.

1 active weather alert

Frost Advisory

Croydon, PA weather

Next 2 hours

Next 48 hours

Days ahead

The outlook

Today

Tomorrow

Sunday

Rest of week

What changed since yesterday

Radar

Rivers

Delaware River at Burlington (IN MLLW)

Neshaminy Creek near Langhorne

Delaware River at Trenton

Assunpink Creek at Trenton

For your home

Heating this week

Heat-pump hours, next 7 days

Comfort

Open the windows?

Is this typical?

Oct 23, today vs a typical year

Last 7 days vs normal

Sun & moon

Sun

Stars tonight? Fair

Moon