Radnor, PA Weather

Delaware County11:50 PM EDT40.05°N, 75.36°WElevation 433 ft
Frost Advisory until 9:00 AM Sat

Current conditions

Mostly Clear
52°
Mostly Clear
Feels like 52°
High 59° Saturday·Low 39° tonight
WindCalm
Humidity54%
Dew point36°
Pressure30.47 inHg
Visibility10 mi
Cloud cover5%
UV index0 Low
Sunrise7:21 AM
Sunset6:12 PM

Observed at Philadelphia, Philadelphia International Airport · 40 min ago

Forecast

10-day

  • Friday Night

    Mostly clear, with a low around 39.

  • Saturday

    Sunny, with a high near 59.

  • Saturday Night

    Clear, with a low around 39.

National Weather Service forecast updated 3 days ago.

Hourly

Hourly forecast
  1. Now Mostly Clear 42°
  2. Sat12 AM Mostly Clear 40°
  3. 1 AM Mostly Clear 39°
  4. 2 AM Mostly Clear 38°
  5. 3 AM Patchy Frost 37°
  6. 4 AM Patchy Frost 37°
  7. 5 AM Patchy Frost 37°
  8. 6 AM Patchy Frost 36°
  9. 7 AM Patchy Frost 35°
  10. 8 AM Patchy Frost 36°
  11. 9 AM Sunny 41°
  12. 10 AM Sunny 46°
  13. 11 AM Sunny 52°
  14. 12 PM Sunny 56°
  15. 1 PM Sunny 58°
  16. 2 PM Sunny 60°
  17. 3 PM Sunny 62°
  18. 4 PM Sunny 62°
  19. 5 PM Sunny 61°
  20. 6 PM Clear 57°
  21. 7 PM Clear 53°
  22. 8 PM Clear 51°
  23. 9 PM Clear 48°
  24. 10 PM Clear 45°

10-day forecast

Details
  1. TueOct 20 Sunny Sunny45°68°
  2. WedOct 21 Mostly Sunny Mostly Sunny43°64°
  3. ThuOct 22 Sunny Sunny43°66°
  4. TodayOct 23 Sunny Sunny39°59°
  5. SatOct 24 Sunny Sunny39°59°
  6. SunOct 25 Sunny Sunny45°65°
  7. MonOct 26 Mostly Sunny Mostly Sunny49°69°
  8. TueOct 27 Partly cloudy Partly cloudy42°68°
  9. WedOct 28 Cloudy Cloudy48°65°
  10. ThuOct 29 Sunny Sunny45°62°

Days after the National Weather Service's seven are MET Norway's outlook, a computer model with no forecaster's review.

Radar

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Weather news near Radnor

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Air quality

49
Good
Fine particles (PM2.5)

Air quality is satisfactory, and air pollution poses little or no risk.

Forecast

  • FriGood (40)
  • SatGood (50)
  • SunModerate (65)

Philadelphia, PA reporting area · 1 hr ago. Data from AirNow (EPA and its state, local and tribal partners); preliminary and subject to change.

Sun & moon

Sunrise 7:21 AM
Sunset 6:12 PM
Daylight 10 h 50 min (−2 min 28 s tomorrow)
Waxing Gibbous · 95% lit
Moonrise 4:38 PM Moonset 4:28 AM
Full moon Oct 26 New moon Nov 9

Almanac

Monthly
Normal high / low64° / 46°
Record high87° (1947)
Record low31° (1969)
Wettest1.92 in (1883)
Yesterday70° / 46°
Month to date2.82 in (normal 2.53 in)

Philadelphia Area, records since 1873. Normals 1991–2020. Data from NOAA's Regional Climate Centers (ACIS).

Nearby

Forecasters' discussion

From the National Weather Service office in PHI, issued 1 hr ago

What Has Changed

Aviation section updated for 00Z TAFs.

Marine section updated.

Key Messages

1. Elevated tide cycles persist due to Post- Tropical Cyclone Josephine well off the coast, resulting in widespread minor coastal flooding continuing for back bay areas in Ocean County, NJ and Sussex County, DE.

2. Frost and freeze impacts tonight and Saturday night where the growing season continues.

Discussion

KEY MESSAGE 1...Elevated tide cycles persist due to Post- Tropical Cyclone Josephine well off the coast, resulting in widespread minor coastal flooding continuing for back bay areas in Ocean County, NJ and Sussex County, DE.

Post-Tropical Cyclone Josephine has pulled away from the region as it's now over the Canadian Maritimes. However elevated water levels persist, mainly in the back bay areas of Ocean County, NJ and Sussex County, Delaware. The Coastal Flood Advisory for these counties is in effect until 7 AM Saturday.

KEY MESSAGE 2...Frost and freeze impacts tonight and Saturday night where the growing season continues.

A Freeze Warning was issued for areas north and west of the I-95 corridor from midnight until 9 AM Saturday where the growing season remains active. For the I-95 corridor and areas south and east, a Frost Advisory was issued from midnight until 9 AM Saturday for all other zones, excluding Sussex County in Delaware and the barrier islands in New Jersey.

As an upper-level trough pivots across the Northeast tonight, a strong mid-level ridge in the Plains to Midwest shifts eastward through the weekend. This will support strong surface high pressure shifting eastward into the Northeast and Mid-Atlantic through the weekend.

A chilly and dry airmass will accompany this strong surface high, and as the high itself settles more overhead, forecast soundings show surface winds decoupling. This will set the stage for efficient radiational cooling both tonight and Saturday night. The forecast lows are in the upper 20s to mid 30s for much of the area (with the only exception along the immediate coastal strip) with a favorable setup for frost and freeze. Some scattered to broken cirrus will be in place overnight. However, the thin cloud coverage will be the only limiting reagent to the efficient radiational cooling. This will probably slow cooling down by a few degrees at best, likely aiding to prevent a widespread freeze situation, but it is not expected to slam the brakes hard on the efficient radiational cooling setup overnight.

Aviation

The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Tonight...VFR. Winds will go calm for a time, then increase slightly out of the north to northeast less than 5 kts after 06Z. High confidence.

Saturday...VFR. Winds 5 kts or less favoring a north to northeast direction early, then shifting more easterly and becoming variable after 18Z. Winds may become calm at times. High confidence.

Saturday night...VFR/SKC. Calm winds. High confidence.

Outlook...

Sunday through Wednesday...VFR. No significant weather expected.

Forecasts, observations and alerts in the United States come from the National Weather Service (NOAA); radar from NOAA's Multi-Radar Multi-Sensor system; satellite imagery from NASA's Global Imagery Browse Services (GIBS) and NOAA's GOES satellites; the map from the U.S. Geological Survey's National Map; air quality from AirNow (EPA and its partners); hurricane information from the National Hurricane Center; climate normals and records from NOAA's Regional Climate Centers (ACIS). Forecasts outside the United States and the UV index: MET Norway (CC BY 4.0); observations outside the U.S.: airport reports via NOAA's Aviation Weather Center. Place names: GeoNames (CC BY 4.0). Data are copied on a schedule and may lag the sources; for warnings that affect your safety, follow your local National Weather Service office and emergency officials. Weather news is drawn from the 4Search index and reflects what the press published. Terms of use.