Frost Advisory
Ends in 8 h 49 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 11:45 PM EDT at KTTN

Morrisville, PA weather

Clear and 39°4°.

Forecasts agree

Now 39°4°

Clear

Wind: Calm; Up to 5 mph8 km/h through 12 PM
Dew point: 34°1°; Dry, static shocks likely
UV index: 0Low; Moderate 11 AM–4 PM · peak 4
Pressure: 30.47 inHg1032 hPa; Rising slowly · +0.03 inHg+0.9 hPa in 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

Low 34°1° today at 6 AM
Above 50°10° today by 10 AM
High 63°17° today at 3 PM
Below 50°10° tonight after 9 PM

TonightNear 37°3° · Clear
This morningUp to 56°13° by 11 AM · Partly cloudy
This afternoonUp to 63°17° by 3 PM · Clear
TonightDown to 35°2° by 4 AM · Clear
Tomorrow morningUp to 56°13° by 11 AM · Clear
Tomorrow afternoonUp to 66°19° by 3 PM · Clear
Tomorrow nightDown to 44°7° by 11 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 12a	Mostly clear	38°3° (likely 38°3° to 45°7°)	38°3°	0%	0 mph0 km/h, gusts 4 mph7 km/h	92%	13%	0
Sat 1a	Clear	38°3° (likely 38°3° to 43°6°)	38°3°	0%	0 mph0 km/h, gusts 4 mph7 km/h	89%	4%	0
Sat 2a	Clear	37°3° (likely 37°3° to 42°6°)	37°3°	0%	0 mph0 km/h, gusts 5 mph8 km/h	92%	1%	0
Sat 3a	Clear	36°2° (likely 36°2° to 42°6°)	36°2°	0%	0 mph0 km/h, gusts 5 mph8 km/h	96%	8%	0
Sat 4a	Partly cloudy	36°2° (likely 36°2° to 40°4°)	36°2°	0%	0 mph0 km/h, gusts 5 mph8 km/h	92%	27%	0
Sat 5a	Partly cloudy	36°2° (likely 36°2° to 40°4°)	36°2°	0%	5 mph8 km/h from N, gusts 4 mph6 km/h	92%	52%	0
Sat 6a	Partly cloudy	34°1° (likely 34°1° to 39°4°)	34°1°	0%	5 mph8 km/h from N, gusts 4 mph6 km/h	100%	70%	0
Sat 7a	Partly sunny	35°2° (likely 35°2° to 39°4°)	35°2°	0%	5 mph8 km/h from N, gusts 5 mph7 km/h	96%	71%	0
Sat 8a	Partly sunny	37°3° (likely 35°2° to 40°4°)	34°1°	0%	5 mph8 km/h from N, gusts 5 mph8 km/h	92%	71%	0
Sat 9a	Sunny	42°6° (likely 41°5° to 45°7°)	42°6°	0%	0 mph0 km/h, gusts 5 mph8 km/h	79%	37%	1
Sat 10a	Sunny	51°11° (likely 49°9° to 51°11°)	51°11°	0%	0 mph0 km/h, gusts 5 mph7 km/h	59%	31%	2
Sat 11a	Mostly sunny	56°13° (likely 53°12° to 56°13°)	56°13°	0%	0 mph0 km/h, gusts 4 mph6 km/h	49%	14%	3
Sat 12p	Sunny	59°15° (likely 57°14° to 59°15°)	59°15°	0%	0 mph0 km/h, gusts 4 mph6 km/h	44%	22%	4
Sat 1p	Sunny	61°16° (likely 59°15° to 61°16°)	61°16°	0%	0 mph0 km/h, gusts 3 mph5 km/h	39%	19%	4
Sat 2p	Sunny	62°17° (likely 61°16° to 62°17°)	62°17°	0%	0 mph0 km/h, gusts 3 mph5 km/h	36%	19%	4
Sat 3p	Sunny	63°17° (likely 61°16° to 63°17°)	63°17°	0%	0 mph0 km/h, gusts 3 mph5 km/h	35%	14%	3
Sat 4p	Sunny	63°17° (likely 61°16° to 63°17°)	63°17°	0%	0 mph0 km/h, gusts 2 mph4 km/h	34%	6%	2
Sat 5p	Sunny	63°17° (likely 60°16° to 63°17°)	63°17°	0%	0 mph0 km/h, gusts 4 mph7 km/h	34%	0%	1
Sat 6p	Clear	60°16° (likely 56°13° to 60°16°)	60°16°	0%	0 mph0 km/h, gusts 4 mph7 km/h	41%	0%	0
Sat 7p	Clear	55°13° (likely 53°12° to 55°13°)	55°13°	0%	0 mph0 km/h, gusts 3 mph5 km/h	49%	0%	0
Sat 8p	Clear	51°11° (likely 50°10° to 52°11°)	51°11°	0%	0 mph0 km/h, gusts 3 mph5 km/h	61%	0%	0
Sat 9p	Clear	45°7° (likely 45°7° to 50°10°)	45°7°	0%	0 mph0 km/h, gusts 4 mph6 km/h	79%	0%	0
Sat 10p	Clear	42°6° (likely 42°6° to 48°9°)	42°6°	0%	0 mph0 km/h, gusts 3 mph5 km/h	89%	0%	0
Sat 11p	Clear	41°5° (likely 41°5° to 46°8°)	41°5°	0%	0 mph0 km/h, gusts 4 mph6 km/h	93%	0%	0
Sun 12a	Clear	39°4° (likely 39°4° to 45°7°)	39°4°	0%	0 mph0 km/h, gusts 4 mph7 km/h	100%	0%	0
Sun 1a	Clear	38°3° (likely 38°3° to 44°7°)	38°3°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	0%	0
Sun 2a	Clear	37°3° (likely 37°3° to 43°6°)	37°3°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	0%	0
Sun 3a	Clear	36°2° (likely 36°2° to 42°6°)	36°2°	0%	0 mph0 km/h, gusts 5 mph7 km/h	100%	0%	0
Sun 4a	Clear	35°2° (likely 35°2° to 41°5°)	35°2°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	0%	0
Sun 5a	Clear	35°2° (likely 35°2° to 40°4°)	35°2°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	1%	0
Sun 6a	Clear	34°1° (likely 34°1° to 40°4°)	34°1°	0%	0 mph0 km/h, gusts 5 mph8 km/h	100%	0%	0
Sun 7a	Sunny	34°1° (likely 34°1° to 40°4°)	34°1°	0%	0 mph0 km/h, gusts 6 mph10 km/h	100%	1%	0
Sun 8a	Sunny	36°2° (likely 36°2° to 39°4°)	36°2°	0%	0 mph0 km/h, gusts 7 mph10 km/h	100%	2%	0
Sun 9a	Sunny	42°6° (likely 40°4° to 45°7°)	42°6°	0%	0 mph0 km/h, gusts 6 mph10 km/h	89%	0%	1
Sun 10a	Sunny	49°9° (likely 49°9° to 53°12°)	49°9°	0%	0 mph0 km/h, gusts 6 mph10 km/h	71%	1%	2
Sun 11a	Sunny	56°13° (likely 56°13° to 58°14°)	56°13°	0%	0 mph0 km/h, gusts 7 mph11 km/h	62%	2%	3
Sun 12p	Sunny	60°16° (likely 60°16° to 61°16°)	60°16°	0%	0 mph0 km/h, gusts 7 mph12 km/h	51%	2%	4
Sun 1p	Sunny	63°17° (likely 62°17° to 64°18°)	63°17°	0%	0 mph0 km/h, gusts 6 mph9 km/h	43%	2%	4
Sun 2p	Sunny	64°18° (likely 63°17° to 65°18°)	64°18°	0%	0 mph0 km/h, gusts 6 mph9 km/h	40%	1%	4
Sun 3p	Sunny	66°19° (likely 63°17° to 66°19°)	66°19°	0%	0 mph0 km/h, gusts 7 mph11 km/h	36%	2%	3
Sun 4p	Sunny	66°19° (likely 63°17° to 66°19°)	66°19°	0%	0 mph0 km/h, gusts 7 mph11 km/h	36%	3%	2
Sun 5p	Sunny	64°18° (likely 62°17° to 64°18°)	64°18°	0%	0 mph0 km/h, gusts 6 mph9 km/h	40%	5%	1
Sun 6p	Clear	60°16° (likely 58°14° to 60°16°)	60°16°	0%	0 mph0 km/h, gusts 3 mph5 km/h	47%	1%	0
Sun 7p	Clear	54°12° (likely 53°12° to 56°13°)	54°12°	0%	0 mph0 km/h, gusts 4 mph7 km/h	61%	1%	0
Sun 8p	Clear	50°10° (likely 50°10° to 54°12°)	50°10°	0%	0 mph0 km/h, gusts 4 mph7 km/h	74%	0%	0
Sun 9p	Clear	47°8° (likely 46°8° to 55°13°)	47°8°	0%	0 mph0 km/h, gusts 2 mph4 km/h	83%	0%	0
Sun 10p	Clear	45°7° (likely 43°6° to 54°12°)	45°7°	0%	0 mph0 km/h, gusts 2 mph4 km/h	89%	0%	0
Sun 11p	Clear	44°7° (likely 40°4° to 54°12°)	44°7°	0%	0 mph0 km/h, gusts 2 mph4 km/h	93%	0%	0

Days ahead

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

Friday, Oct 23. Cloudy. High 61°16°, low 44°7°. Typical 63°17° / 43°6°. Dry. Forecasts agree.
1. Overnight
  midnight–6 AM
  Clear, 36°2°
  Dry
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
60°16°–61°16°
Low, likely
43°6°–46°8°
Typical high / low
63°17° / 43°6°
Wind
11 mph17 km/h, gusts 24 mph38 km/h
UV peak
4
Today, Oct 24. Cloudy. High 63°17°, low 34°1°. Typical 62°17° / 43°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 37°3°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 51°11°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 35°2°
  Dry
Official NWS forecast
Day: Areas of frost before 10am. Sunny, with a high near 63. Northeast wind 0 to 5 mph.
Night: Areas of frost. Partly cloudy, with a low around 34. Northeast wind 0 to 5 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
61°16°–63°17°
Low, likely
34°1°–39°4°
Typical high / low
62°17° / 43°6°
Wind
5 mph9 km/h
UV peak
4
Tomorrow, Oct 25. Sunny. High 66°19°, low 38°3°. Typical 62°17° / 42°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 36°2°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 66°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 50°10°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 42°6°
  Dry
Official NWS forecast
Day: Areas of frost before 9am. Sunny, with a high near 66. West wind around 0 mph.
Night: Clear, with a low around 38. Northwest wind around 0 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
63°17°–66°19°
Low, likely
36°2°–39°4°
Typical high / low
62°17° / 42°6°
Wind
5 mph9 km/h
UV peak
4
Monday, Oct 26. Mostly sunny. High 69°21°, low 47°8°. Typical 62°17° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 41°5°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 57°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 47.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
67°19°–69°21°
Low, likely
36°2°–47°8°
Typical high / low
62°17° / 42°6°
Wind
7 mph11 km/h, gusts 24 mph38 km/h
UV peak
4
Tuesday, Oct 27. Partly sunny. High 66°19°, low 43°6°. Typical 61°16° / 42°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 49°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 62°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 51°11°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 41°5°
  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 43.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
61°16°–66°19°
Low, likely
43°6°–49°9°
Typical high / low
61°16° / 42°6°
Wind
9 mph14 km/h, gusts 26 mph41 km/h
UV peak
4
Wednesday, Oct 28. Partly sunny. High 63°17°, low 46°8°. Typical 61°16° / 41°5°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 41°5°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 61°16°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 53°12°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 46°8°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 63.
Night: Mostly cloudy, with a low around 46.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
59°15°–64°18°
Low, likely
39°4°–46°8°
Typical high / low
61°16° / 41°5°
Wind
7 mph12 km/h, gusts 18 mph29 km/h
UV peak
4
Thursday, Oct 29. Partly sunny. High 68°20°, low 50°10°. Typical 61°16° / 41°5°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 47°8°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 66°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°15°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 50°10°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 68.
Night: Partly cloudy, with a low around 50.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
63°17°–69°21°
Low, likely
45°7°–50°10°
Typical high / low
61°16° / 41°5°
Wind
8 mph13 km/h, gusts 29 mph47 km/h
UV peak
4
Friday, Oct 30. Sunny. High 70°21°, low 49°9°. Typical 60°16° / 41°5°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 50°10°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 69°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.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
65°18°–73°23°
Low, likely
47°8°–50°10°
Typical high / low
60°16° / 41°5°
Wind
8 mph14 km/h, gusts 24 mph38 km/h
UV peak
4
Saturday, Oct 31. Partly sunny. High 68°20°, low 47°8°. Typical 60°16° / 40°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 47°8°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 67°20°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 47°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°–72°22°
Low, likely
40°4°–53°12°
Typical high / low
60°16° / 40°4°
Wind
9 mph15 km/h, gusts 25 mph41 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, 65°19°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 58°14°
  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°–71°22°
Low, likely
46°8°–54°12°
Typical high / low
60°16° / 40°4°
Wind
11 mph17 km/h, gusts 20 mph32 km/h
UV peak
4

10 days15 days30 days

The outlook

Today
Dry, high 61°, low 44°.
Tomorrow
Dry, high 63°, low 34°.
Sunday
Dry, high 66°, low 38°, warming up.
Rest of week
Mostly dry, highs 63–70°.

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 Trenton

1.0 mi

Below flood stage

Level: 8.7 ft
Flow: 4,580 cfs

Forecast peak 8.6 ft Sat 2 AM

Reading from Fri 10:15 PM · NWS gauge page

Assunpink Creek at Trenton

2.0 mi

Below flood stage

Level: 2.9 ft
Flow: 71 cfs

Forecast peak 2.9 ft Sat 2 AM

Reading from Fri 10:15 PM · NWS gauge page

Delaware River at Washington Crossing

7.6 mi

Below flood stage

Level: -1.4 ft

Forecast peak -1.3 ft Sat 2 AM

Reading from Fri 10 PM · NWS gauge page

Neshaminy Creek near Langhorne

9.6 mi

Below flood stage

Level: 1.1 ft
Flow: 123 cfs

Forecast peak 1.1 ft Sat 2 AM

Reading from Fri 10:15 PM · NWS gauge page

For your home

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

Heating this week

About 64% less heating than a typical week.

This week 33Typical 92

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 20 hours are near freezing and damp, when outdoor units defrost more often.

Comfort

Dry air outside (dew point 34°F).

Open the windows?

Today, 1:00 PM–6:00 PM

Good stretch to open the windows (air quality forecast not available for part of this window).

Is this typical?

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

Oct 24, today vs a typical year

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

Last 7 days vs normal

On average 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

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

Sun & moon

Sun

Daylight: 10 h 47 min; Losing 2 min 30 s a day; shortest Dec 21, 1 h 28 min less
Golden hour: 5:28–6:23 PM; Morning 7:02–7:57 AM
Blue hour: 6:23–6:34 PM; Morning 6:51–7:02 AM; first light 6:51 AM

Stars tonight? Fair

Mostly clear 12:11–4 AM, but the moon is 96% lit and up.

Moon

Waxing gibbous

95% lit · growing

Today: sets 5:30 AM · rises 5:03 PM
Full moon: Oct 26
New moon: Nov 9

Looking south from Morrisville. The highest point on the skyline is about 2,200 ft, 5 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

Morrisville, 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 Trenton

Assunpink Creek at Trenton

Delaware River at Washington Crossing

Neshaminy Creek near Langhorne

For your home

Heating this week

Heat-pump hours, next 7 days

Comfort

Open the windows?

Is this typical?

Oct 24, today vs a typical year

Last 7 days vs normal

Sun & moon

Sun

Stars tonight? Fair

Moon