How to tell if temperature is what's waking you up

The key takeaways

• It's hard to tell what's waking you, because it happens while you're asleep. You remember the wake-up, not what led up to it.
• A few signs point to heat: waking warm or damp, waking more on warm nights or under heavier bedding, and a partner who's comfortable under the same covers.
• Two weeks of short morning notes can show a pattern. They can't show your temperature.
• The Orion Sleep Disruption Test measures one night at home and lays your temperature next to every interruption. A sleep advisor can then turn that curve into settings for your bed.

Why it's hard to tell on your own

You wake at 3am, warm, with the duvet pushed down. By morning you have a theory: the room, the comforter, your partner, the glass of wine. But whatever woke you happened while you were asleep, and nobody was watching.

Your body is meant to cool down at night. In the hours before sleep, core temperature starts to fall as more blood flows to the hands and feet and heat leaves through the skin. According to the Sleep Foundation, that drop continues through the night and reaches its low point in the early morning. A warm room, heavy bedding or a partner's body heat can all work against it.

Signs and notes get you part of the way. To see what your temperature was actually doing when you woke, the Orion Sleep Disruption Test measures it for you in one night at home.

Signs that point to heat

No single sign settles it, but a few together point toward temperature.

Do you wake up warm, damp or reaching to cool down?

If the first thing you do on waking is kick off the covers, flip the pillow or put a foot out, heat is probably part of it. The same goes for waking flushed or with a damp neck.

Does it follow the weather or the bedding?

Notice whether it happens more on warm nights, in summer, or since you switched to a heavier comforter or added a foam topper. If your partner sleeps comfortably under the same covers while you're too warm, that points the same way.

Does it happen whatever the room is like?

If you wake at the same time on cool nights and warm ones, or wake without feeling warm at all, temperature may not be the main cause. There's a section on other causes further down.

Keep notes for two weeks

A notebook on the nightstand is a simple way to start. Two weeks is long enough for a pattern to show.

• Put a simple thermometer near the bed, where it won't pick up a draft from the door or window.
• Each morning, jot down roughly when you woke, whether you felt hot, cold or neither, and what you slept under.
• Each evening, note anything that might add heat: alcohol, a late meal, a late workout, a hot bath.
• If you share the bed, ask your partner to note when they woke too. You may find you're both waking.
• At the end, look for wake-ups that line up with warmer nights, heavier bedding or a particular evening.

See what's happening overnight with the Sleep Disruption Test

The Orion Sleep Disruption Test is a one-night, at-home test that maps your body temperature across the night and shows where your sleep was interrupted.

How the test works

The kit comes with a single sensor patch. Right before bed, you activate it in the Orion app and stick it to the side of your ribcage, just below your underarm. Then you sleep as you normally would. In the morning, you scan the patch with your phone. There's nothing to charge, nothing to wear on your wrist and nothing to mail back.

Take it on an ordinary night rather than waiting for a good one. If you toss and turn or wake up hot, that's exactly what the report needs to see.

What your report shows

Your report is usually ready the next day. It shows how your body temperature moved through the night, how much it rose and fell, and each point where your sleep was interrupted.

Seen side by side, you can tell whether your wake-ups came as your temperature climbed, or with no change at all. Either answer is useful.

Going through it with a sleep advisor

Each test includes a one-on-one call with an Orion sleep advisor, who helps you work out whether temperature is part of what's waking you. On the call, they walk you through your temperature curve which shows how your body warmed and cooled throughout the night and each point where your sleep was disrupted. If your results suggest something worth raising with a doctor, they'll tell you.

If temperature does look like a factor, your advisor can turn your results into settings for an Orion Sleep System. The call is recommended but optional, so you can ask for the report on its own.

If you share a bed

Each person needs their own patch, phone and Orion account, and you don't have to test on the same night. Two reports make it easier to see whose wake-ups follow the heat.

From your report to your bed

The test measures. If heat turns out to be what's waking you, the Orion Sleep System is how you act on it. It adds heating and cooling to the mattress you already own, with each side set separately from 50°F to 113°F.

If you go on to get Orion after your test, your sleep advisor uses your temperature curve to set its starting schedule, so it starts from your own night rather than a guess.

If you already know you want to control the temperature of your bed, you can buy the Orion Sleep System directly. The test is optional.

If the signs don't point to heat

Waking hot doesn't always start in the bedroom. The NHS lists hot flashes, anxiety, some medicines, low blood sugar and alcohol among the common causes of night sweats.

See a doctor if night sweats soak your bedding even in a cool room, regularly wake you or worry you, or come with a fever, a cough, diarrhea or weight loss you can't explain. Talk to a doctor too if someone has told you that you snore loudly or stop breathing in your sleep.

Questions people ask about waking up hot

How can I find out if temperature is waking me up at night?

Look for the signs first: waking warm or damp, more often on warm nights or under heavier bedding. Two weeks of notes can show a pattern. To see your temperature directly, the Orion Sleep Disruption Test records it through one night at home and shows it next to every interruption.

Why do I wake up hot at 3am?

Core temperature falls through the night and reaches its low point in the early morning, according to the Sleep Foundation. Waking hot around then usually means something is adding heat, such as the room, the bedding, a partner, alcohol earlier in the evening, or a hot flash.

What do I need to take the Sleep Disruption Test?

The patch from the kit, the Orion app, and a phone with NFC switched on, which you use to activate the patch at bedtime and scan it in the morning.

Does the Sleep Disruption Test diagnose sleep apnea?

No. The Orion Sleep Disruption Test is not a medical device and does not diagnose sleep disorders. If you think you might have sleep apnea, talk to a doctor.

Ready to see what your temperature does overnight? Find out why with the Orion Sleep Disruption Test.