Replay

Historical model replay

The February 7–9, 2026 cold snap, replayed complaint by complaint and scored by the frozen model on IBM LinuxONE.

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scoring: — Download saved top-500 ranking ↓

Inspection queue — top 25 in this replay

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HeatAhead help

JavaScript is off, so the chat cannot open. You can read the guides and answers below.

How HeatAhead works

Check the weather

Forecasts show when freezing weather is expected.

Look at past problems

Past complaints, violations and building records help the model estimate heating risk.

Choose what to do

Tenants and owners can review a building. Inspectors can see which places the model suggests checking first.

A student project by NYU Tingineers for the IBM Z Datathon. The model work ran on IBM LinuxONE. HeatAhead is independent of NYC311 and HPD.

Read the map

Color shows winter risk

Darker blue means higher estimated risk. A hexagon shows the average score of the properties inside it. Zoom in to see each property's colored dot.

Height shows past complaints

Taller hexagons mean more heating complaints were recorded last season. They don't show the number of buildings or their actual height.

Click a hexagon

You'll see a list of buildings, with higher scores first. Use Next to see more. Click a building in the list to open its record.

Zoom in for a closer look

The city view uses larger hexagons so it's easier to read. Zoom in to see smaller areas, then colored dots for each property. Gray building shapes come from the background map. One property record can cover more than one building.

Try the map →

Understand the scores

Check which score you're reading

Winter risk covers the whole season. Cold-day risk looks at a shorter period around freezing weather. They cover different lengths of time, so the numbers can be different.

See how it was checked

On a building's page, open How accurate is this number? It compares predictions with what happened in a winter the model wasn't trained on. This helps check the model overall, but can't say for sure what will happen to one building.

A high score doesn't mean the heat has failed. A low score doesn't rule out a problem.
Some heating problems never get reported, so they may be missing from the records.
From 20% up, scores are shown as ranges. No score goes above 99%.
If a building has no score, we don't have an estimate for it. It can still have heating problems.

Check a building →

What you can do

For tenants

Check your building's history and the available owner details. Sign in to save a building for email alerts. Emails also need the team's alert service to be running.

Building alerts →

For owners & managers

Review your building's history and draft a message about checking the heating. You can edit the message and send it yourself.

Check your building →

For city teams

Use the monitor to review published complaints. Its separate historical replay shows model priorities changing during a past cold spell.

See published complaints

Data and privacy

We use public NYC records about buildings, heat complaints, violations, owners and boilers, along with weather data. Some records may be missing or out of date. A complaint means someone reported a problem; it doesn't mean an inspector confirmed it.

HPD complaints ↗ HPD violations ↗ NYC PLUTO properties ↗ Open-Meteo weather ↗

The map is about buildings, not individual tenants. Saving a building for alerts links it to your verified email. HeatAhead doesn't see your Google password. Owner and agent details come from public business records.

When you sign in with Google, we receive only your verified email address, your name and Google's account id for you; we keep no Google access tokens and ask for no Drive, Gmail or contacts access. An email sign-in link uses your address the same way. Your saved buildings, alert choices and dashboard panels are stored on the team's own server and are never sold or shared. You can remove a saved building or stop every alert from your profile at any time, and signing out clears the sign-in cookie on that device.

The help chat uses published answers. It can suggest close matches when a question is unclear or has a typo. Common questions stay on your device. If AI matching is enabled, an unfamiliar question and the previous help topic may be sent to a provider to suggest a published question. Your Google account details and earlier messages aren't included. We don't save guide chats in this app. Please leave out passwords, contact details and apartment numbers.

The photos were taken earlier; they aren't live. The guide can show you where to go. Sending a message, reporting a problem or changing alerts is still up to you.

What is HeatAhead?

HeatAhead uses weather and past building records to estimate where heating problems are more likely in NYC. You can check a building, explore the map or see which places may need an inspection. The score is an estimate, not a live check of the heating.

How do I check my building?

Go to Check a building. Enter its street address and borough, or its 10-digit BBL, then choose Look up. You'll see the available risk score, complaint history and owner details. Leave out your apartment number.

What is a BBL?

A BBL is NYC's 10-digit property ID, short for Borough, Block and Lot. One ID can cover more than one building. If you don't know it, you can search using the street address instead.

How do I use the map?

The map covers all five boroughs. Use the Minimum risk slider to hide lower scores, or Jump to an area to choose a borough. Switch between Flat map and 3D view. Zoom in to see colored dots for individual properties.

What happens when I click a hexagon?

The city view uses larger hexagons so the map is easier to read. Zoom in to see smaller areas, then dots for individual properties. Click a hexagon to see its buildings, with higher scores first. Your current filter still applies. Use Next to see more, or Zoom to these buildings to look closer. Click a building in the list to open its record.

Why are some hexagons taller?

Taller hexagons mean more heating complaints were recorded in that area last season. A few buildings with lots of complaints can make a tall hexagon. Height doesn't show how many buildings there are. When you zoom in, the gray building shapes and their heights come from the background map.

What do the map colors mean?

Darker blue means higher estimated winter risk. A hexagon shows the average score of the properties inside it. When you zoom in, each colored dot shows one property's score. Height shows past complaints, which is a different measure.

What does winter risk mean?

It's the estimated chance of a heating problem at some point this winter, based on the building's records. It doesn't tell you whether the heat is working right now. Open the building's page to see its score and history.

Why are the winter and cold-day scores different?

Winter risk covers the whole season. Cold-day risk looks at a much shorter period around freezing weather. A building has more time to run into a problem over a whole winter, so the two scores can be quite different. Compare scores that cover the same period.

How accurate are the scores?

On a building's page, open How accurate is this number? It compares predictions with what happened in a winter that wasn't used to train the model. This helps check the model overall; it can't tell us for sure what will happen to one building. From 20% up, we show ranges, and no score goes above 99%.

Why do some buildings have no hexagons or color?

The background map shows more buildings than we've scored. Some properties have missing records or map locations, and filters can hide lower scores. Some 3D hexagons stay flat because no complaints were recorded there last season. Try Flat map. When you zoom in, dots replace hexagons. A building without color can still have heating problems. Try resetting the filter or looking up its address.

Where does the information come from?

We use public NYC records about buildings, heat complaints, violations, owners and boilers, along with weather data. Records can be missing or out of date. A complaint means someone reported a problem; it doesn't mean an inspector confirmed it.

What information do you keep about me?

The map shows information about buildings, not individual tenants. Saving a building for alerts links it to your verified email address. Owner details come from public business records. Please leave passwords, email addresses, phone numbers and apartment numbers out of the guide chat.

How do I sign up or sign in?

Choose Sign in on the home page. When available, use Continue with Google or request an email sign-in link. The email link works once for 15 minutes. The same options create your account or sign you back in. If both are being set up, you can still check buildings and use the map without an account.

Will I stay signed in when I come back?

Tick Keep me signed in for 30 days on this device before signing in with Google or requesting an email link. Your browser may end the session sooner if you clear cookies or use stricter privacy settings. Use the same email address to find your saved buildings again. Sign out if you're on a shared device.

How do I get email alerts?

When sign-in is available, sign in and find Save a building in your profile. Enter its street address and borough, or BBL, tick the email-alert box and choose Save to my account. Turn on My buildings & alerts to see saved buildings on your dashboard. Emails are sent for qualifying forecast cold spells when the team's alert service is running.

How do I stop alerts or remove a building?

Sign in with the same email address you used to save the building. Turn on My buildings & alerts in your profile if needed. Under Your saved buildings, choose Stop alerts & remove. You can also use the unsubscribe link in an alert email and confirm the removal.

How can landlords use HeatAhead?

Look up your building to check its history and available owner or agent details. Choose I own or manage it under Draft a notice to prepare a message about a heating check. If you sign in, you can turn on Landlord self-audit tools in your profile. That dashboard choice doesn't verify ownership.

How do I write a message about my building?

On the building's page, find Draft a notice. Choose the tenant or landlord option, then click Draft the notice. Read and edit the message, then copy it or open your email app. You send it yourself. Owner records may list a mailing address rather than an email address.

How can city teams use the monitor?

Open Published complaints to review recent reports. The separate Historical model replay shows how building priorities change during a past cold spell. These are planning and demonstration tools, not HPD’s official inspection schedule.

Is the live monitor showing what's happening now?

Published complaints shows recent heat reports released by NYC, with a delay. It refreshes every 15 seconds while the source is checked every five minutes; it doesn't confirm an outage is still active. Historical model replay is separate: it replays February 7–9, 2026 complaints to show rankings changing. Check the replay clock for its date. Building pages and the map still work if the monitor is offline.

What should I do if I have no heat or hot water?

Tell your landlord, superintendent or managing agent. If the problem isn't fixed, report it to NYC311. Give your contact and apartment details directly to NYC311. You don't need to wait for a high score or an email alert to report a heating problem.

What are NYC's heating rules?

NYC heat season runs from October 1 to May 31. From 6 AM to 10 PM, your home must be at least 68°F when it's below 55°F outside. From 10 PM to 6 AM, it must be at least 62°F, whatever the outdoor temperature. Hot water must reach at least 120°F all year. See HPD's page for the official rules.

Are the building photos live?

No. The aerial photos and Google Street View images were taken earlier, and their dates and coverage vary. Street View opens the closest available view. The location marker shows the property's mapped position. Gray building shapes come from the background map; they don't show whether the heating works.

Does a high score mean my heat will definitely fail?

No. A higher score means the model thinks a heating problem is more likely, but it can't say for sure. Some problems never get reported, and records and forecasts can be wrong. Use the score to help decide what to check. A real heating problem should still be reported, whatever the score.

What if I smell gas or a carbon monoxide alarm sounds?

Leave the building and call 911 from outside. HeatAhead can't send emergency help. For a heating problem without immediate danger, contact your landlord and NYC311.

How do I contact the HeatAhead team?

Email heataheadnyc@gmail.com with questions, feedback or corrections. A building's street address or BBL is enough; leave out apartment details, passwords and sign-in links. For a heating complaint, use NYC311. Our team inbox doesn't file reports or send inspectors.

How do I change my cookie choices?

Choose Accept all, Reject optional or Settings in the cookie banner. You can reopen Cookie settings in the footer any time. Optional storage remembers dashboard choices on this device and starts off until you accept it. Rejecting it doesn't sign you out or remove saved buildings. Essential sign-in cookies stay on. HeatAhead doesn't use analytics or advertising cookies; the privacy page explains external map and photo services.