New Castle County, DE Weather Forecast
County weather hub
Sunny
Compare major city weather across New Castle County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
Sunny, with a high near 99. Heat index values as high as 104. West wind 5 to 10 mph.
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
- Jul 15 to Jul 21, 2026
- Latest sync
- Jul 14, 2026 8:38 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 99 degrees F.
Sunday Night is the coolest period ahead with temperatures near 70 degrees F.
The strongest winds are forecast for Wednesday at about 5 to 10 mph W.
Precipitation is mentioned in 8 upcoming forecast periods.
Forecast Details
- Last updated
- Jul 14, 2026 8:38 PM EDT
- Coverage
- 7 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
Partly cloudy, with a low around 76. Heat index values as high as 102. Northwest wind 0 to 10 mph.
Mostly sunny, with a high near 95. Northwest wind 0 to 10 mph.
Partly cloudy, with a low around 73. Northwest wind around 5 mph.
Mostly sunny, with a high near 93.
A chance of showers and thunderstorms after 2am. Partly cloudy, with a low around 71. Chance of precipitation is 30%.
A chance of showers and thunderstorms before 2pm, then showers and thunderstorms likely. Partly sunny, with a high near 87. Chance of precipitation is 60%.
Showers and thunderstorms likely before 8pm, then a chance of showers and thunderstorms. Mostly cloudy, with a low around 72. Chance of precipitation is 60%.
A chance of showers and thunderstorms. Partly sunny, with a high near 90. Chance of precipitation is 40%.
A chance of showers and thunderstorms before 2am. Partly cloudy, with a low around 70. Chance of precipitation is 40%.
A slight chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90.
A slight chance of showers and thunderstorms before 8pm, then a chance of showers and thunderstorms. Partly cloudy, with a low around 71. Chance of precipitation is 30%.
A chance of rain showers before 8am, then a chance of showers and thunderstorms. Partly sunny, with a high near 90.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Wednesday
Jul 15
|
Sunny
|
99°F |
5 to 10 mph
W
|
|
Wednesday Night
Jul 15
|
Partly Cloudy
|
76°F |
0 to 10 mph
NW
|
|
Thursday
Jul 16
|
Mostly Sunny
|
95°F |
0 to 10 mph
NW
|
|
Thursday Night
Jul 16
|
Partly Cloudy
|
73°F |
5 mph
NW
|
|
Friday
Jul 17
|
Mostly Sunny
|
93°F |
5 mph
N
|
|
Friday Night
Jul 17
|
Partly Cloudy then Chance Showers And Thunderstorms
|
71°F |
0 to 5 mph
SE
|
|
Saturday
Jul 18
|
Chance Showers And Thunderstorms
|
87°F |
0 to 10 mph
S
|
|
Saturday Night
Jul 18
|
Showers And Thunderstorms Likely then Chance Showers And Thunderstorms
|
72°F |
5 mph
SW
|
|
Sunday
Jul 19
|
Chance Showers And Thunderstorms
|
90°F |
5 to 10 mph
W
|
|
Sunday Night
Jul 19
|
Chance Showers And Thunderstorms
|
70°F |
5 mph
NW
|
|
Monday
Jul 20
|
Mostly Sunny then Slight Chance Showers And Thunderstorms
|
90°F |
5 mph
W
|
|
Monday Night
Jul 20
|
Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms
|
71°F |
5 mph
S
|
|
Tuesday
Jul 21
|
Chance Rain Showers
|
90°F |
5 to 10 mph
SW
|
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.
