New Castle County, DE Weather Forecast
County weather hub
Mostly Sunny then Chance Showers And Thunderstorms
Compare major city weather across New Castle County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
A chance of showers and thunderstorms between 2pm and 5pm, then showers and thunderstorms likely. Mostly sunny, with a high near 93. West wind 5 to 10 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
County Weather Overview
This county weather page brings together forecast coverage for New Castle County so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 4 of 4 mapped cities in New Castle County.
Page Snapshot
- Page focus
- county weather
- Forecast window
- May 20 to May 25, 2026
- Latest sync
- May 19, 2026 7:17 PM EDT
- Forecast office
- PHI
- Source
- NOAA / NWS
Daily Outlook
This Week in New Castle County
Wednesday looks like the warmest upcoming period in New Castle County at 93 degrees F.
Friday Night is the coolest period ahead with temperatures near 50 degrees F.
The strongest winds are forecast for Wednesday at about 5 to 10 mph W.
Precipitation is mentioned in 12 upcoming forecast periods.
Forecast Details
- Last updated
- May 19, 2026 7:17 PM EDT
- Coverage
- 6 days
- Time zone
- America/New_York
- Forecast office
- PHI
- Radar station
- KDOX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Showers and thunderstorms likely before 10pm, then a chance of showers and thunderstorms. Cloudy, with a low around 57. North wind 5 to 10 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
A chance of rain showers before 8am, then showers and thunderstorms likely. Mostly cloudy, with a high near 65. Northeast wind 5 to 10 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
A chance of rain showers. Mostly cloudy, with a low around 51. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
Rain showers likely. Mostly cloudy, with a high near 63. Chance of precipitation is 60%.
Rain showers. Mostly cloudy, with a low around 50. Chance of precipitation is 80%.
Rain showers. Mostly cloudy, with a high near 64. Chance of precipitation is 80%.
Rain showers likely before 8pm, then showers and thunderstorms likely. Mostly cloudy, with a low around 54. Chance of precipitation is 70%.
A chance of rain showers before 2pm, then a chance of showers and thunderstorms. Mostly cloudy, with a high near 72. Chance of precipitation is 50%.
Showers and thunderstorms likely. Mostly cloudy, with a low around 58. Chance of precipitation is 60%.
A chance of rain showers before 2pm, then a chance of showers and thunderstorms. Mostly cloudy, with a high near 77. Chance of precipitation is 50%.
A chance of showers and thunderstorms. Mostly cloudy, with a low around 59.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Wednesday
May 20
|
Mostly Sunny then Chance Showers And Thunderstorms
|
93°F |
5 to 10 mph
W
|
|
Wednesday Night
May 20
|
Showers And Thunderstorms Likely then Chance Showers And Thunderstorms
|
57°F |
5 to 10 mph
N
|
|
Thursday
May 21
|
Showers And Thunderstorms Likely
|
65°F |
5 to 10 mph
NE
|
|
Thursday Night
May 21
|
Chance Rain Showers
|
51°F |
0 to 5 mph
E
|
|
Friday
May 22
|
Rain Showers Likely
|
63°F |
5 to 10 mph
E
|
|
Friday Night
May 22
|
Rain Showers
|
50°F |
5 to 10 mph
E
|
|
Saturday
May 23
|
Rain Showers
|
64°F |
10 mph
E
|
|
Saturday Night
May 23
|
Showers And Thunderstorms Likely
|
54°F |
5 to 10 mph
NE
|
|
Sunday
May 24
|
Chance Rain Showers
|
72°F |
5 mph
E
|
|
Sunday Night
May 24
|
Showers And Thunderstorms Likely
|
58°F |
5 mph
E
|
|
Memorial Day
May 25
|
Chance Rain Showers
|
77°F |
5 mph
N
|
|
Monday Night
May 25
|
Chance Showers And Thunderstorms
|
59°F |
0 to 5 mph
E
|
Major City Forecasts
Live forecast snapshots for major cities across New Castle County.
Coverage
Forecast coverage currently spans 4 of 4 mapped cities in New Castle County.
Largest mapped city population in this region: 70,376.