diff --git a/environment.yaml b/environment.yaml
index ad1bbfbd..4c2837c2 100644
--- a/environment.yaml
+++ b/environment.yaml
@@ -10,7 +10,7 @@ channels:
 - defaults
 dependencies:
 - python>=3.6
-- numpy
+- numpy<2
 - scipy
 - pandas>=0.25
 - xarray>=0.16.2
diff --git a/setup.py b/setup.py
index a2841620..cff82621 100644
--- a/setup.py
+++ b/setup.py
@@ -24,7 +24,7 @@
     include_package_data=True,
     python_requires=">=3.6",
     install_requires=[
-        "numpy",
+        "numpy<2",
         "scipy",
         "pandas>=0.25",
         "bottleneck",