How weather closures work · Flex Weather Tracker

In short: drivers commonly report that a delivery station closes its doors when it isn't safe for drivers and associates to be out in the lot; station leadership makes the call. Lightning close by, tornado warnings, extreme wind, heat or cold, dense fog, smoke and incidents at the site are the reasons the tracker watches for; ordinary rain is not one of them. This guide covers each one, the tracker's 6-mile lightning rule and 30-minute all-clear, why the weather and the station's decision don't always match, what the tracker's colours mean, the seasonal pattern, and what to check before a block.

Why stations close for weather

Pickup puts a lot of people on foot in the open. Drivers describe walking between their cars and the pickup area, waiting in line and loading in the lot, with associates moving carts in and out of the building around them. A crowd in an open parking lot has nowhere good to go when a dangerous storm arrives, and that is the reason drivers most often hear for a closure: with the doors shut, nobody is out in the lot until the danger passes. Station leadership makes the call, and the closures drivers report tend to follow weather you can't safely stand out in, not weather that is merely unpleasant. A downpour makes loading miserable, but in the tracker's reading heavy rain and flood reports show as advisories, not closures.

The kinds of weather that can close a station

The tracker treats these kinds of report as the ones that go with a closure. The figures come from the tracker's own wording for each report; they describe the reports, not a rulebook every station follows.

Lightning close by. A ground strike within 6 miles of the station. A busy thunderstorm afternoon can bring this more than once; the tracker's rule is explained below.
Tornado warnings. A tornado warning from the National Weather Service or Environment Canada whose area covers the station. A warning means a tornado has been sighted or shown by radar and people in its path should take shelter now. A tornado watch only means conditions could produce tornadoes somewhere in a large area, and the tracker shows it as an advisory.
Extreme wind. Extreme wind warnings, and gusts above 50 mph, which turn carts, totes and loose packaging into hazards.
Extreme heat. A heat index of 115°F or more. Hot days below that usually bring heat advisories instead.
Extreme cold. A wind chill of -40°F or colder. Snow, ice and other winter weather show as advisories.
Very low visibility. Dense fog with visibility under 100 feet, in a lot full of moving cars and people on foot.
Very bad air quality. Usually smoke from wildfires.
Something going on at the station. Not weather at all: a police matter or another incident at the site. The tracker picks these up from police dispatch and local news reports and words them vaguely on purpose: "Something is going on at the station. It might be closed."

The tracker's 6-mile lightning rule and 30-minute all-clear

The tracker reads lightning closures by a simple rule, and knowing it helps you guess how long one may last. The tracker flags a station when a lightning ground strike lands within 6 miles of it, and counts the station as clear 30 minutes after the most recent strike inside that circle. Drivers commonly report that stations reopen on about the same clock; station leadership makes the call.

The detail that matters is that, in the tracker's rule, every new strike inside 6 miles restarts the 30-minute clock. Say a strike lands 4 miles from the station at 3:10 PM. The all-clear is 3:40. Another strike lands 5 miles away at 3:25, and the all-clear moves to 3:55. A strike 8 miles away at 3:30 doesn't move it, because it's outside the circle. This is why a slow storm that lingers nearby can keep a station red on the tracker, and, drivers report, the doors shut, long after the rain has stopped at the station.

Only ground strikes count; cloud-to-cloud flashes are ignored. Strikes between 6 and 10 miles are flagged more loosely as lightning in the area: a sign that a storm is close, not a closure. And drivers commonly report that the doors don't open the moment the clock runs out. The tracker estimates a minute and a half to three minutes for an associate to get to them, and its alerts tell you to allow about 4 minutes more.

Why the weather and the station don't always agree

The tracker reads weather reports; it doesn't see inside the station or make the decision. The two can differ for good reasons:

Leadership makes the call. Drivers report stations closing before any report is posted, when staff could see a storm arriving, and working through a report when leadership judged it safe.
Reports cover areas, stations are points. An advisory covers an area, and a tornado warning is drawn as a shape along a storm's path. A storm at the edge of an area can leave a station untouched.
End times move. While conditions last, an advisory's end time is often renewed every 15 to 30 minutes, so the end time you see is not a promise that the doors open then.
Not every closure is weather. Drivers also report closures on calm days, put down to a power cut, an equipment problem or an incident on site. The tracker only sees the incidents that reach police dispatch or the local news.

Signed-in drivers can also report a station closed or open from its details. A report shows beside the weather status for 30 minutes without changing it.

What the colours on the tracker mean

Red: weather reports indicate a closed station. The most severe report around the station is one of the closure-level kinds above. The reports look like a closure; the station hasn't necessarily confirmed one.
Amber: weather advisories near the station. Something is active below that level, such as lightning in the area, a wind, heat or winter weather advisory, or a tornado watch.
Green: no local weather advisories.
Tornado icon: the station sits inside an active tornado warning.
Lightning marks: ground strikes from the last 30 minutes, fading as they age. The slider under the map replays them minute by minute, the quickest way to see whether a storm is heading for the station or moving away.

How closures change with the seasons

Summer: afternoon and evening thunderstorms. Heat and humidity build through the day, storms pop up in the afternoon, and the tracker can show a station red for lightning, clear and red again before dark; drivers commonly report closures that follow the same rhythm. In the most humid places, the heat index itself can reach the closure level.
Spring: tornado season. Lines of severe storms bring tornado warnings, damaging wind and lightning together, especially across the Plains, the Midwest and the South, and they can arrive at any hour, overnight included.
Fall: quieter, with exceptions. Thunderstorms ease off in most places, but tropical storms can still bring closure-level wind to coastal stations, and wildfire smoke can linger in the West.
Winter: wind, cold and fog. Arctic air can push wind chills to dangerous levels in the northern states and Canada, winter storms bring strong winds, and dense fog tends to form on calm, cold mornings.

A checklist for the start of a block

Open the tracker before you leave and find your station. Is it red, amber or green?
If there's lightning around, open the station's details for the chance of a ground strike within 6 miles in the next 20 minutes, and play the lightning replay to see which way the storm is moving.
If the station is red, note the estimated reopening time and which block start times may be cancelled. The blocks guide explains that window.
Check the Flex app. It is the final word on your block, whatever the tracker shows.
If lightning is within 6 miles when you arrive, wait in your car with the windows up, and take screenshots of the app and the tracker so you have the times.
Turn on alerts for your station so you hear about the next closure without having to check. A free account gets phone notifications for one station; the paid plans add email and more stations.

The Flex Weather Tracker is an independent tool and is not affiliated with Amazon. Station leadership makes the final call on every closure.

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