diff --git a/environment-dev.yml b/environment-dev.yml
index 41f40a6..d3fbd8e 100644
--- a/environment-dev.yml
+++ b/environment-dev.yml
@@ -30,9 +30,8 @@ dependencies:
   - pint
   - pint-pandas
   - pint-xarray
-
+  - tzfpy
   - pip
   - pip:
-    - timezonefinder[numba]
     - codetiming
     - hydroutils
diff --git a/hydrodataset/caravan.py b/hydrodataset/caravan.py
index ad1ff21..9965c62 100644
--- a/hydrodataset/caravan.py
+++ b/hydrodataset/caravan.py
@@ -11,7 +11,7 @@
 from urllib.request import urlopen
 import pandas as pd
 import numpy as np
-from timezonefinder import TimezoneFinder
+from tzfpy import get_tz
 from hydroutils import hydro_file
 from hydrodataset import CACHE_DIR, HydroDataset
 
@@ -532,9 +532,9 @@ def cache_attributes_xrdataset(self):
 
         # for attrs not from hydroatlas in caravan, we directly set pint unit
         units_dict["area"] = "km^2"
-        units_dict[
-            "area_fraction_used_for_aggregation"
-        ] = "dimensionless"  # this one is from atlas but not specified in the document
+        units_dict["area_fraction_used_for_aggregation"] = (
+            "dimensionless"  # this one is from atlas but not specified in the document
+        )
         units_dict["aridity"] = "dimensionless"
         units_dict["country"] = "dimensionless"
         units_dict["frac_snow"] = "dimensionless"
@@ -748,7 +748,7 @@ def _check_data(self, regions):
                         _data.set_index(["date"])
                     )
                     the_ncfile_data.attrs = attrs
-                    tf = TimezoneFinder()
+                    # tf = TimezoneFinder()
                     site_meta_file = os.path.join(
                         self.data_source_description["ATTR_DIR"],
                         region,
@@ -763,7 +763,7 @@ def _check_data(self, regions):
                     lon = df_metadata.loc[
                         df_metadata.index == gage_id, "gauge_lon"
                     ].values[0]
-                    the_ncfile_data.attrs["Timezone"] = tf.timezone_at(lat=lat, lng=lon)
+                    the_ncfile_data.attrs["Timezone"] = get_tz(lat=lat, lng=lon)
                     the_ncfile = os.path.join(
                         os.path.dirname(file_path), f"{gage_id}.nc"
                     )
diff --git a/hydrodataset/hydro_dataset.py b/hydrodataset/hydro_dataset.py
index 9fa0df4..2783f2e 100644
--- a/hydrodataset/hydro_dataset.py
+++ b/hydrodataset/hydro_dataset.py
@@ -1,16 +1,19 @@
 """
 Author: Wenyu Ouyang
 Date: 2022-09-05 23:20:24
-LastEditTime: 2023-07-27 21:44:01
+LastEditTime: 2024-02-20 19:33:43
 LastEditors: Wenyu Ouyang
 Description: main modules for hydrodataset
 FilePath: \hydrodataset\hydrodataset\hydro_dataset.py
 Copyright (c) 2021-2022 Wenyu Ouyang. All rights reserved.
 """
-from pathlib import Path
+
 from abc import ABC
+from pathlib import Path
 from typing import Union
+
 import numpy as np
+
 from hydrodataset import ROOT_DIR
 
 
@@ -63,7 +66,8 @@ def read_other_cols(
         self, object_ids=None, other_cols: dict = None, **kwargs
     ) -> dict:
         """some data which cannot be easily treated as constant vars or time-series with same length as relevant vars
-        CONVENTION: other_cols is a dict, where each item is also a dict with all params in it"""
+        CONVENTION: other_cols is a dict, where each item is also a dict with all params in it
+        """
         raise NotImplementedError
 
     def get_constant_cols(self) -> np.array:
diff --git a/requirements.txt b/requirements.txt
index bec01f2..425aa1c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,7 @@ scipy
 pint
 pint-pandas
 pint-xarray
-timezonefinder[numba]
+tzfpy
 codetiming
 
-hydroutils
\ No newline at end of file
+hydroutils
diff --git a/requirements_dev.txt b/requirements_dev.txt
index ac36262..8d9fbbd 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -22,7 +22,7 @@ scipy
 pint
 pint-pandas
 pint-xarray
-timezonefinder[numba]
+tzfpy
 codetiming
 
 hydroutils
\ No newline at end of file