Philadelphia records about 1076mm of rain across roughly 117 wet days a year, which is a 32% chance on an average day. July is the wettest month at 101mm (9% of the annual total) and February the driest at 67mm. Local rain type: thunderstorms. Philly gets rain in every season — summer thunderstorms, autumn Nor'easters, winter snow-rain mix. The Reading Terminal Market is perfect shelter.
Chance of rain on an average day: 32%
Rainfall climatology for Philadelphia. The live hour-by-hour answer for today loads at the top of this page from Open-Meteo and refreshes through the day — the figures below describe a typical year, not today.
Last updated: · Live forecast data refreshes hourly.
| Annual rainfall | 1076mm |
| Rain days per year | 117 |
| Odds on an average day | 32% |
| Wettest month | July — 101mm over 11 days |
| Driest month | February — 67mm over 8 days |
| Rain type | thunderstorms |
| Best dry window | October offers the most pleasant balance of dry weather and autumn colors. |
| Worst rain window | June through August brings humid thunderstorms, and winter brings Nor'easters. |
July delivers 51% more rain than February (101mm vs 67mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 9% of the annual total, so rain in Philadelphia is spread through the year — there is no season you can rely on being dry.
Philadelphia rain arrives in short, heavy bursts — shelter and timing matter more than gear.
Rain falls on about 11 days in July against 8 in February — the frequency swing matters more for planning than the millimetre totals.
Climate normals. Use them to judge whether today's live forecast at the top of the page is typical or unusual for the season.
| Month | Rainfall | Rain days | Chance on a given day | Highs |
|---|---|---|---|---|
| January | 79mm | 9 | 30% | 4°C |
| February | 67mm | 8 | 27% | 4°C |
| March | 95mm | 11 | 37% | 8°C |
| April | 89mm | 10 | 33% | 14°C |
| May | 84mm | 10 | 33% | 20°C |
| June | 92mm | 10 | 33% | 26°C |
| July | 101mm | 11 | 37% | 30°C |
| August | 96mm | 11 | 37% | 30°C |
| September | 93mm | 11 | 37% | 26°C |
| October | 76mm | 9 | 30% | 20°C |
| November | 74mm | 8 | 27% | 14°C |
| December | 82mm | 9 | 30% | 8°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Philadelphia we combine the hourly probability curve, expected volume in millimetres, and the city's own rainfall record into a single umbrella verdict.
| Factor | Weight | What it measures |
|---|---|---|
| Hourly probability | 40% | Peak and sustained chance of measurable rain across the next 24 hours. |
| Expected volume | 30% | Total millimetres, which separates a passing shower from a genuine soaking. |
| Timing & duration | 20% | When rain starts, when it eases, and the longest continuous dry window. |
| Local rain type | 10% | Drizzle, brief showers, thunderstorms or monsoon — each needs different gear. |
Live hourly values come from Open-Meteo and refresh through the day. Monthly rainfall figures are climate normals, so they describe a typical year rather than a forecast.
Philadelphia records rain on roughly 117 days a year — about a 32% chance on any given day — totalling around 1076mm.
July, with about 101mm over 11 rain days. That is 9% of the entire year's rainfall in a single month.
February is the driest month at 67mm across roughly 8 days. October offers the most pleasant balance of dry weather and autumn colors.
Philly gets rain in every season — summer thunderstorms, autumn Nor'easters, winter snow-rain mix. The Reading Terminal Market is perfect shelter.
No. Probability is the chance that at least 0.2mm of rain falls at your location at some point in the period. Check the expected millimetres alongside it: 40% with 0.4mm is a passing shower, 40% with 12mm is a soaking.