Check the Hail History Before You Knock on the Door

A storm goes through on Tuesday night. By Thursday morning every roofer in the metro has the same idea: get in a truck, drive the neighborhoods that took the worst of it, and start knocking.

Most of that driving is wasted. The storm was narrow. One street got hail that mattered and the next street over got rain. A crew that works from a rumor, a social media post or a gut feeling spends a morning on doors where there is nothing to find, and the homeowners on those doors learn to dislike the sight of a roofing truck.

The contractors who do this well start from a different question: what do we actually know about this roof, and this address, before anyone rings the bell?

Where Radar Hail Data Comes From

The National Oceanic and Atmospheric Administration publishes a radar product called MESH, the Maximum Estimated Size of Hail. It is built by combining readings from the weather radar network and estimating, for each small cell of ground, how large the biggest hail was across a storm day. The data is public.

BetterRoofingPro reads that public archive and turns each storm day into shaded bands on the prospecting map, one band for each size threshold. Higher bands stack on top of lower ones, so the map shows both how far a storm reached and where its heaviest hail fell. Click a band and it tells you the storm day and that storm's peak estimated size.

A History for the Address, Not Just the Storm

The map answers where the storm went. The property view answers a more useful question: how often has this roof been under one?

Open a property and the Storm Exposure section lists every storm day, within a look-back window, on which a radar band covered that exact point. Each entry gives the date, the largest size band that covered the property, and the storm's peak size elsewhere. Newest first.

That list changes the conversation in three ways.

It ranks the doors. An address under a heavy band last week and another under a heavy band two years ago are different opportunities. A roof with several storm days on it is a better bet than one that was clipped once at the edge of a light band.

It gives you a date. The first thing a homeowner or an adjuster asks is when it happened. Knowing the storm day lets you say "the radar shows hail came through on this date" instead of "there was some weather a while back." The date also lines up with what the homeowner remembers, which is what makes the conversation easy.

It keeps you honest about the quiet ones. When a property has no entries, the panel says no radar-detected hail at or above the smallest band is on record for that location. That is useful. It tells you to look at the other doors first.

What the Radar Does Not Tell You

This is the part that matters most, and the part that gets skipped.

It is an estimate, not a measurement. MESH is an algorithm applied to radar returns. It is not a hailstone in someone's hand. It can disagree with what actually fell on a given street, in either direction, and it works at a resolution of a neighborhood, not a roof.

It is not proof of damage. Hail of a given size may or may not damage a given roof, depending on the material, its age, its pitch and what it was already carrying. The radar tells you where to look. Only an inspection tells you what is there.

Radar artifacts exist. Radar sometimes reads something that is not hail as hail. BetterRoofingPro runs quality-control rules that set aside storms that look implausible rather than drawing them, so a stored storm can be missing from the map on purpose. A blank is not a guarantee of no hail, and a band is not a guarantee of hail.

The archive may not be complete. The history depends on how far back the stored archive reaches in your environment, and a recent storm day may take a while to appear after NOAA publishes it. An empty list can mean nothing was detected, or it can mean the day has not been loaded yet. If a homeowner swears a storm hit, take that seriously and inspect.

So the right sentence at the door is "radar estimated hail in your area on this date, and I would like to check the roof," not "your roof was damaged by hail." The first is true. The second is something you do not know until you are on the ladder.

Turn It Into a Routine

A routine beats enthusiasm. After a storm day, decide who looks at the map, how soon, and what counts as worth a visit. Put the top addresses in a list, check each one's history, and take the ones with the strongest and most recent storm days first. Record what the inspection found against the lead, whether or not it was a roof worth selling, so next time you know whether the radar bands in your market tend to match what is on the shingles.

Rules about soliciting homeowners door to door, and about what you may say after a storm, vary by state and locality, and some states regulate roofing sales after a weather event specifically. Ask your own counsel what applies where you work before you build a canvassing routine around any data source.

Where to Start

Next time a storm hits your market, resist the drive. Look at the map first. Choose a short list of addresses on the strength of their history, and visit those. Then compare what you found with what the radar suggested. That comparison is worth more than any sales script, because it tells you how far to trust the tool in your own territory.