diff --git a/build_envs/environment.yml b/build_envs/environment.yml
index f292805..d8de4c6 100644
--- a/build_envs/environment.yml
+++ b/build_envs/environment.yml
@@ -3,7 +3,7 @@ name: wrf_python_build
 channels:
   - conda-forge
 dependencies:
-  - python>=3.9, <3.13
+  - python>=3.9
   - compilers
   - basemap
   - cartopy
diff --git a/pyproject.toml b/pyproject.toml
index 5047e19..6880ebb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,7 +12,7 @@ maintainers = [
 ]
 description = "Diagnostic and interpolation routines for WRF-ARW data."
 readme = "README.md"
-requires-python = ">=3.9, <3.13"
+requires-python = ">=3.9"
 keywords = [
     "python", "wrf-python", "wrf", "forecast", "model",
     "weather research and forecasting", "interpolation",
diff --git a/src/wrf/constants.py b/src/wrf/constants.py
index d660c62..ff9c0df 100644
--- a/src/wrf/constants.py
+++ b/src/wrf/constants.py
@@ -59,7 +59,7 @@ class ProjectionTypes(object):
                      np.dtype(np.uint32): 4294967295,
                      np.dtype(np.int64): Constants.DEFAULT_FILL_INT64,
                      np.dtype(np.uint64): 18446744073709551614,
-                     np.dtype(np.float_): Constants.DEFAULT_FILL_DOUBLE,
+                     np.dtype(np.float64): Constants.DEFAULT_FILL_DOUBLE,
                      np.dtype(np.float32): Constants.DEFAULT_FILL_FLOAT,
                      np.dtype(np.float64): Constants.DEFAULT_FILL_DOUBLE
                      }