Weather in Gaithersburg, Maryland for September 2026
Small Craft Advisory - See hour by hour.
So far, September 2026 in Gaithersburg shows a warmer trend than usual by 3.1 °F.
Expect cooler weather in the next days in Gaithersburg with the forecast suggesting a temperature of 25.2 °F, lower than the historical average.
In general, the average temperature in Gaithersburg at the beginning of September is 30.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 24.1 °F by the end of September.
The climate of Gaithersburg in September is notably wet, with an average of 11 rainy days, and a total of 240.9 mm of precipitation.
New! Chat with our AI weatherman - it’s amazing and free.
Official Weather Alert ⚠️
Temperatures
Rain 🌧️
More
Gaithersburg Weather September
Temperatures trend during September in Gaithersburg
September weather in Gaithersburg day by day
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 31° /17° | 0 mm | 8 | |
| Sept. 2 | Overcast | 30° /18° | 5.7 mm | 8 | |
| Sept. 3 |  Cloudy | 30° /18° | 0 mm | 7 | |
| Sept. 4 |  Partly cloudy | 33° /20° | 17.7 mm | 9 | |
| Sept. 5 |  Mist | 31° /19° | 2.5 mm | 8 | |
| Sept. 6 |  Moderate or heavy rain shower | 31° /17° | 54.4 mm | 8 | |
| Sept. 7 | Overcast | 26° /14° | 0 mm | 6 | |
| Sept. 8 |  Sunny | 27° /11° | 0 mm | 8 | |
| Sept. 9 | Partly cloudy | 27° /14° | 0 mm | 7 | |
| Sept. 10 |  Light rain shower | 29° /19° | 7.5 mm | 4.7 | |
| Sept. 11 | Overcast | 22° /18° | 6.1 mm | 5.8 | |
| Sept. 12 | Overcast | 26° /16° | 0 mm | 5 | |
| Sept. 13 | Mist | 27° /20° | 4.2 mm | 6.9 | |
| Sept. 14 | Patchy rain possible | 30° /21° | 1.3 mm | 6 | |
| Sept. 15 | Sunny | 32° /23° | 1.3 mm | 8 | |
| Sept. 16 | Sunny | 32° /23° | 0 mm | 8 | |
| Sept. 17 | Sunny | 28° /16° | 0 mm | 7 | |
| Sept. 18 | Sunny | 23° /14° | 13.1 mm | 6 | |
| Sept. 19 | Sunny | 18° /8° | 0 mm | 5 | |
| Sept. 20 | Sunny | 20° /8° | 0 mm | 5 | |
| Sept. 21 | Sunny | 22° /10° | 0 mm | 6 | |
| Sept. 22 | Sunny | 24° /12° | 0 mm | 6 | |
| Sept. 23 | Overcast | 20° /14° | 0 mm | 5 | |
| Sept. 24 | Mist | 27° /18° | 0 mm | 5 | |
| Sept. 25 | Moderate or heavy rain shower | 26° /17° | 31.6 mm | 1 | |
| Sept. 26 | Mist | 26° /19° | 10.1 mm | 3 | |
| Sept. 27 | Overcast | 23° /15° | 0 mm | 3 | |
| Sept. 28 | Mist | 18° /16° | 13.3 mm | 1 | |
| Sept. 29 | Fog | 25° /15° | 0 mm | 1 | |
| Sept. 30 | Overcast | 24° /17° | 0 mm | 1 | |
| Next | |||||
Gaithersburg in September - FAQ
What are the expected maximum and minimum temperatures in Gaithersburg during September?
How much rainfall should be expected in Gaithersburg during September?
What are the typical wind conditions in Gaithersburg during September?
September rainfall patterns in Gaithersburg
UV exposure in Gaithersburg during September
Quick links
Where is Gaithersburg?Get accurate weather forecasts for Gaithersburg, located at latitude 39.143 and longitude -77.201. Stay updated with localized weather information tailored for Gaithersburg.