Grant River
Tonight: low 53 °F, heavy dew.
Nights by month
Night lows from 2016 to 2025: a typical night, and the cold one that comes 1 night in 10.
The mildest nights are in July, typically 66°F. The coldest are in January, when 1 night in 10 drops to -8°F. Frost is common in January, February, March, April, November and December.
- Jan16°F -8°FBag comfortable to -10°F · frost 95% · rain or snow 28% of days
- Feb16°F -4°FBag comfortable to -5°F · frost 91% · rain or snow 23% of days
- Mar29°F 18°FBag comfortable to 20°F · frost 63% · rain or snow 34% of days
- Apr39°F 28°FBag comfortable to 30°F · frost 22% · rain or snow 38% of days
- May51°F 41°FBag comfortable to 40°F · frost 0% · rain or snow 39% of days
- Jun63°F 55°FBag comfortable to 55°F · frost 0% · rain or snow 36% of days
- Jul66°F 61°FBag comfortable to 60°F · frost 0% · rain or snow 36% of days
- Aug64°F 57°FBag comfortable to 60°F · frost 0% · rain or snow 32% of days
- Sep (this month)59°F 50°FBag comfortable to 50°F · frost 0% · rain or snow 30% of days
- Oct45°F 34°FBag comfortable to 35°F · frost 7% · rain or snow 33% of days
- Nov31°F 20°FBag comfortable to 20°F · frost 54% · rain or snow 27% of days
- Dec23°F 5°FBag comfortable to 5°F · frost 88% · rain or snow 26% of days
| = 32°F
History: ERA5 and ERA5-Land reanalysis via Open-Meteo, corrected to the site's elevation. Bag rating: the comfort rating that keeps you warm in a tent on 9 of 10 nights that month.
Tonight
Good nightFriday, September 25, 10 p.m. to 7 a.m.
Your selected gear looks warm enough
About 16 °F to spare at the coldest hour.
This is based on typical values for the gear types you picked, so treat it as an estimate.
Your night
- 10 p.m. until morningComfortableAir around you 62 to 55°F, heavy dew.
Every hour
- 10 p.m.62°Fcomfortable, heavy dew
- 11 p.m.61°Fcomfortable, heavy dew
- midnight60°Fcomfortable, some dew
- 1 a.m.62°Fcomfortable
- 2 a.m.60°Fcomfortable
- 3 a.m.59°Fcomfortable
- 4 a.m.57°Fcomfortable
- 5 a.m.57°Fcomfortable
- 6 a.m.56°Fcomfortable, some dew
- 7 a.m.55°Fcomfortable
This spot sits about 24 m below the land around it. On clear, calm nights cold air pools here, so expect it colder and wetter than the forecast.
Times are local time at your spot (GMT-5).
What works tonight
The gear this night calls for, for someone who sleeps like you.
- You have this
Sleeping bag
Comfort 55°F or colder
Usually sold as a 46° bag. The number in a bag's name is the limit, not the comfort.
- You have this
Underneath you
R1 or more
The R-value says how well a pad keeps the cold ground out.
Before you sleep
- Your spot sits lower than the ground around it. On a clear, calm night cold air drains into spots like this, so expect it colder and wetter than the forecast. If you can, move a little higher up, away from the creek or valley floor.
- Bring shoes, clothes and electronics inside. Anything left out will be wet by morning.
- Open the tent vents and keep the door zip open a bit at the top. Some condensation inside is normal on a night like this, so bring a small towel to wipe it off.
How we estimated this
At the coldest hour (7 a.m.):
- Outside at your spot
- 53°F
- Warmth your shelter holds
- +2 °F
- Air around you
- 55°F
- Your bag's comfort rating
- 39°F
- Your comfort limit
- 39°F
16 °F to spare, so warm enough.
Assumptions
- Bag categories use typical ratings as sold: summer about 50 °F (10 °C), 3-season about 30 °F (-1 °C), winter about 15 °F (-9 °C). The number in a bag's name is usually its lower limit, so its comfort rating is about 9 °F (5 °C) warmer.
- What you lie on: foam mat about R2, thin air pad about R1.5, insulated pad about R3.5, winter pad R5 and up, van bed about R4, air mattress about R0.5. Colder ground needs a higher R-value.
- Shelters hold a few degrees early in the night and less towards morning. Wind and clear, calm skies take warmth away.
- Weather: Open-Meteo forecast for your spot, on a grid of a few kilometers, corrected to its height.
- These are rules of thumb, not measurements. People and gear vary.
A forecast, not a promise. Mountains, valleys and water make their own weather, so trust what you see and feel on site. Terms and liability
Checked for a double-wall tent, a 3-season bag and a thin air pad. Check your own gear here.
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