How to check the weather along a drive tomorrow

Doing it by hand

1. Write down when you’ll pass each place. Take your departure time and your map app’s driving time, and note roughly when you’ll reach each town or big interchange along the way. Add your planned stops.
2. Look up the hourly forecast for each place, for that hour. Not today’s summary: the hour you’ll be there. The National Weather Service’s hourly forecast at weather.gov lets you click any point on a map.
3. Check for alerts along the route. Winter storm warnings, flood warnings and high wind warnings are issued for counties, so check the ones you’ll drive through, not just your own.
4. Check road conditions in winter. Most states run a 511 traveler information service, by phone and online, with closures, chain controls and plowing.
5. Look again in the morning. A forecast for tomorrow afternoon will be sharper by the time you leave. If the bad weather is timed to cross your route, leaving an hour or two earlier or later can be the whole difference.

It works, but it’s a lot of lookups for a long drive, and it all has to be redone if your plans change.

What to watch for

• Thunderstorms: heavy rain and hail can drop visibility to almost nothing for a few minutes; they’re usually short, so waiting one out at an exit often beats driving through.
• Freezing rain and snow: the temperature at the hour you pass matters more than the day’s high. A road that’s fine at 2 pm can freeze after dark.
• Strong crosswinds: a problem for tall vehicles, trailers and motorcycles, especially on open highway and bridges.
• Fog: often in valleys and near water early in the morning.

Doing it with Viltri

This is the job Viltri was built for. Enter the trip once, with your departure, and for each drive leg Viltri takes the route and driving time from Apple Maps, checks 12 points along the road, and shows the forecast for the time you’re expected to reach each one. Stretches with rain, snow or thunderstorms are grouped and marked Caution or Warning, with the miles and times they cover.

Planning your own trips is part of Viltri Premium; the free plan includes a demo trip that shows the route forecast. Viltri’s forecasts in the US come from the National Weather Service.

Related

• Viltri vs Drive Weather
• How to see the weather for every stop of a multi-city trip
• What app shows the weather along my road-trip route?
• Free flight-day airport weather check