Atla Bank
atl — water, in Nahuatl. A bank of water records for Belize.
Rainfall normals, river stages, hurricane landfalls and flood history, gathered from public bulletins and kept in one place so farmers, builders and the curious can see what the water has done before.
Latest river bulletin
Rainfall through the year
Belize is not one climate. Toledo gets more rain in June alone than Cayo sees from January to May. The chart shows approximate monthly normals for three stations; the dip in March and April is the dry season everyone plans around.
River stations
The National Hydrological Service reports each river in stage terms rather than metres: below normal, normal, above normal, bankfull, flood stage, or relative to a local landmark such as the San Ignacio low-level bridge. Each station shows its most recent logged stage.
Hurricane landfalls
Every tropical cyclone known to have made landfall in Belize or passed close enough to do damage, placed by year and shaded by its category at landfall. Most arrive in September and October; Lisa in 2022 and the 1942 storm are the only November hurricanes on record.
Flood events
Floods in Belize usually come from rain that fell somewhere else: over the Petén for the Mopan, over the Maya Mountains for the Macal, over Honduras for the storms that stall there. These are the events where rivers reached flood stage or villages were evacuated.
Before you build near a river
Lots along the Mopan, Macal and Belize River are sold every year to people who have never seen them in October. A few things worth checking before you pour a foundation.
Ask what 2008 and 2020 looked like
The October 2008 and November 2020 floods are the recent high-water marks for the Belize River system. Neighbours, the village council and the NHS can tell you how far the water came on your reach. Look for stain lines on older buildings.
Find your nearest gauge
Know which station the NHS bulletins use for your stretch of river. When they say "Mopan at Benque is approaching bankfull", you want to already know what that means at your fence line.
Flashy rivers rise fast
The Macal can come up in hours after rain in the Mountain Pine Ridge, and the dams spilling adds to it. The Mopan is slower but holds high water for days. Plan access, not just the house.
Rain here is not the whole story
A dry week in Benque means little if it has rained for a week in Melchor and the Petén. Watch the NHS forecast, not just the sky.
Drainage and culverts
Low spots on a lot that are dry in March become ponds in September. Check how water leaves the lot and whether the road culverts are sized for it.
Planting calendars
In Cayo the rains arrive in late May or June and taper in November. Toledo's wet season starts earlier and never really stops. Use the rainfall chart to see your district's shape.
About the data
Atla Bank is an independent, volunteer-maintained archive of public water information for Belize. It has no connection to any financial institution, and it collects no personal information.
Every figure here comes from a public source and is labelled with how much to trust it. Approximate values are compiled from published summaries and will be replaced with official station data as it becomes available. Corrections and new bulletins are welcome.
If you are at risk from flooding, follow the National Hydrological Service, the National Meteorological Service and NEMO directly. This site is a record, not a warning system.