diff --git a/dep_tools/grids.py b/dep_tools/grids.py
index 73e8ec2..ec5c3a8 100644
--- a/dep_tools/grids.py
+++ b/dep_tools/grids.py
@@ -115,7 +115,6 @@ def grid(
             Otherwise, a GeoDataFrame containing only the portions of each tile
             that intersect the given GeoDataFrame is returned.
     """
-
     if intersect_with is not None:
         if return_type != "GridSpec":
             full_grid = _geoseries(resolution, crs)
diff --git a/dep_tools/landsat_utils.py b/dep_tools/landsat_utils.py
index 74d35f1..f0b8ae3 100644
--- a/dep_tools/landsat_utils.py
+++ b/dep_tools/landsat_utils.py
@@ -6,7 +6,7 @@
 from shapely.geometry import box
 from xarray import DataArray, Dataset
 
-from dep_tools.utils import bbox_across_180
+from dep_tools.utils import bbox_across_180, fix_winding
 
 
 def cloud_mask(
@@ -66,13 +66,20 @@ def mask_clouds(
         return xr.where(~mask)
 
 
+def _pathrows():
+    pathrows = GeoDataFrame(
+        read_file(
+            "https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/atoms/files/WRS2_descending_0.zip"
+        )
+    )
+    pathrows["geometry"] = pathrows.geometry.apply(fix_winding)
+    return pathrows
+
+
 def pathrows_in_area(area: GeoDataFrame, pathrows: GeoDataFrame | None = None):
     if pathrows is None:
-        pathrows = GeoDataFrame(
-            read_file(
-                "https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/atoms/files/WRS2_descending_0.zip"
-            )
-        )
+        pathrows = _pathrows()
+
     bbox = bbox_across_180(area)
     if isinstance(bbox, tuple):
         return pathrows[
@@ -99,9 +106,7 @@ def items_in_pathrows(
 
 
 def pathrow_with_greatest_area(shapes: GeoDataFrame) -> Tuple[str, str]:
-    pathrows = read_file(
-        "https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/atoms/files/WRS2_descending_0.zip"
-    )
+    pathrows = _pathrows()
     intersection = shapes.overlay(pathrows, how="intersection")
     row_with_greatest_area = intersection.iloc[[intersection.geometry.area.idxmax()]]
     return (row_with_greatest_area.PATH.item(), row_with_greatest_area.ROW.item())
diff --git a/dep_tools/searchers.py b/dep_tools/searchers.py
index e6f00b5..38406a6 100644
--- a/dep_tools/searchers.py
+++ b/dep_tools/searchers.py
@@ -34,7 +34,9 @@ class PystacSearcher(Searcher):
     :func:`dep_tools.utils.search_across_180`.
 
     Args:
-        client: A search client.
+        catalog: The URL of a stac catalog. if client is specified, this is
+            ignored.
+        client: A search client. Either this or catalog must be specified.
         raise_empty_collection_error: Whether an EmptyCollectionError exception
             should be returned if no stac items are found.
         **kwargs: Additional arguments passed to client.search(). For example,
@@ -44,11 +46,20 @@ class PystacSearcher(Searcher):
 
     def __init__(
         self,
-        catalog: str,
+        catalog: str | None = None,
+        client: Client | None = None,
         raise_empty_collection_error: bool = True,
         **kwargs,
     ):
-        self._client = Client.open(catalog)
+        if client and catalog:
+            warnings.warn(
+                "Arguments for both 'client' and 'catalog' passed to PystacSearcher, ignoring catalog"
+            )
+
+        if not (client or catalog):
+            raise ValueError("Must specify either client or catalog")
+
+        self._client = client if client else Client.open(catalog)
         self._raise_errors = raise_empty_collection_error
         self._kwargs = kwargs
 
@@ -65,12 +76,12 @@ def search(self, area: GeoDataFrame | GeoBox) -> ItemCollection:
             region=area, client=self._client, **self._kwargs
         )
 
-        if len(item_collection) == 0 and self._raise_errors:
-            raise EmptyCollectionError()
-
         fix_bad_epsgs(item_collection)
         item_collection = remove_bad_items(item_collection)
 
+        if len(item_collection) == 0 and self._raise_errors:
+            raise EmptyCollectionError()
+
         return item_collection
 
 
@@ -80,7 +91,9 @@ class LandsatPystacSearcher(PystacSearcher):
     query, just use :class:PystacSearcher.
 
     Args:
-        client: A search client.
+        catalog: The URL of a stac catalog. if client is specified, this is
+            ignored.
+        client: A search client. Either this or catalog must be specified.
         raise_empty_collection_error: Whether an EmptyCollectionError exception should
             be returned if no stac items are found.
         search_intersecting_pathrows: Whether to use landsat pathrows which
@@ -99,7 +112,8 @@ class LandsatPystacSearcher(PystacSearcher):
 
     def __init__(
         self,
-        catalog: str = "https://planetarycomputer.microsoft.com/api/stac/v1/",
+        catalog: str | None = None,
+        client: Client | None = None,
         collections: list[str] | None = ["landsat-c2-l2"],
         raise_empty_collection_error: bool = True,
         search_intersecting_pathrows: bool = False,
@@ -110,6 +124,7 @@ def __init__(
     ):
         super().__init__(
             catalog=catalog,
+            client=client,
             raise_empty_collection_error=raise_empty_collection_error,
             **kwargs,
         )
@@ -140,16 +155,9 @@ def __init__(
 
         self._kwargs["query"] = query
 
-        if self._search_intersecting_pathrows:
-            self._landsat_pathrows = read_file(
-                "https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/atoms/files/WRS2_descending_0.zip"
-            )
-
     def search(self, area: GeoDataFrame):
         search_area = (
-            pathrows_in_area(area, self._landsat_pathrows)
-            if self._search_intersecting_pathrows
-            else area
+            pathrows_in_area(area) if self._search_intersecting_pathrows else area
         )
         try:
             items = super().search(search_area)
@@ -164,4 +172,7 @@ def search(self, area: GeoDataFrame):
         if self._search_intersecting_pathrows:
             items = items_in_pathrows(items, search_area)
 
+        if len(items) == 0 and self._raise_errors:
+            raise EmptyCollectionError()
+
         return items
diff --git a/dep_tools/utils.py b/dep_tools/utils.py
index cb7e70b..43be0fe 100644
--- a/dep_tools/utils.py
+++ b/dep_tools/utils.py
@@ -17,7 +17,13 @@
 from pystac import ItemCollection
 import pystac_client
 from retry import retry
-from shapely.geometry import LineString, MultiLineString, GeometryCollection
+from shapely.geometry import (
+    LineString,
+    MultiLineString,
+    GeometryCollection,
+    MultiPolygon,
+)
+from shapely.geometry.polygon import orient
 from xarray import DataArray, Dataset
 
 # Set the timeout to five minutes, which is an extremely long time
@@ -108,6 +114,23 @@ def bbox_across_180(region: GeoDataFrame | GeoBox) -> BBOX | tuple[BBOX, BBOX]:
         return BBOX(bbox)
 
 
+from shapely import Geometry
+
+
+def fix_winding(geom: Geometry) -> Geometry:
+    """Fixes the orientation of the exterior coordinates of Polygon and
+    MultiPolygon geometry, which should run counterclockwise.
+    """
+    # This is non-essential but resolves a barrage of warnings from
+    # the antimeridian package
+    if geom.geom_type == "Polygon" and not geom.exterior.is_ccw:
+        return orient(geom)
+    elif geom.geom_type == "MultiPolygon":
+        return MultiPolygon([fix_winding(p) for p in geom.geoms])
+    else:
+        return geom
+
+
 def _fix_geometry(geometry):
     if isinstance(geometry, GeometryCollection):
         return GeometryCollection(
diff --git a/tests/test_fix_winding.py b/tests/test_fix_winding.py
new file mode 100644
index 0000000..7630db4
--- /dev/null
+++ b/tests/test_fix_winding.py
@@ -0,0 +1,8 @@
+from shapely.geometry import Polygon, MultiPolygon
+from dep_tools.utils import fix_winding
+
+
+def test_fix_winding():
+    bad_poly = Polygon(shell=[[0, 0], [0, 1], [1, 1], [1, 0], [0, 0]])
+    assert not bad_poly.exterior.is_ccw
+    assert fix_winding(bad_poly).exterior.is_ccw
diff --git a/tests/test_landsat_mspc_stac_api.py b/tests/test_landsat_mspc_stac_api.py
index f4e4e38..7579433 100644
--- a/tests/test_landsat_mspc_stac_api.py
+++ b/tests/test_landsat_mspc_stac_api.py
@@ -29,6 +29,7 @@ def test_hobart_all(hobart_area):
         exclude_platforms=None,
         only_tier_one=False,
         fall_back_to_tier_two=False,
+        catalog="https://planetarycomputer.microsoft.com/api/stac/v1/",
     )
 
     items = list(searcher.search(hobart_area))
@@ -42,6 +43,7 @@ def test_hobart_tier_one_only(hobart_area):
         exclude_platforms=None,
         only_tier_one=True,
         fall_back_to_tier_two=False,
+        catalog="https://planetarycomputer.microsoft.com/api/stac/v1/",
     )
 
     items = list(searcher.search(hobart_area))
@@ -55,6 +57,7 @@ def test_hobart_tier_exclude_7(hobart_area):
         exclude_platforms=["landsat-7"],
         only_tier_one=False,
         fall_back_to_tier_two=False,
+        catalog="https://planetarycomputer.microsoft.com/api/stac/v1/",
     )
 
     items = list(searcher.search(hobart_area))
diff --git a/tests/test_landsat_mspc_stac_search_fixes.py b/tests/test_landsat_mspc_stac_search_fixes.py
index e891dad..111423e 100644
--- a/tests/test_landsat_mspc_stac_search_fixes.py
+++ b/tests/test_landsat_mspc_stac_search_fixes.py
@@ -27,7 +27,9 @@ def test_pathrows_in_area(near_antimeridian_area):
 
 def test_search_for_stac_items_with_bad_geoms(near_antimeridian_area):
     searcher = LandsatPystacSearcher(
-        datetime=DATETIME, search_intersecting_pathrows=True
+        datetime=DATETIME,
+        search_intersecting_pathrows=True,
+        catalog="https://planetarycomputer.microsoft.com/api/stac/v1/",
     )
 
     items = searcher.search(near_antimeridian_area)
diff --git a/tests/test_searchers.py b/tests/test_searchers.py
index b0f347c..f27fddd 100644
--- a/tests/test_searchers.py
+++ b/tests/test_searchers.py
@@ -36,7 +36,10 @@ def test_PystacSearcher(area, mspc_catalog):
 
 
 def test_LandsatPystacSearcher_exclude_platforms(area):
-    s = LandsatPystacSearcher(exclude_platforms=["landsat-7"])
+    s = LandsatPystacSearcher(
+        exclude_platforms=["landsat-7"],
+        catalog="https://planetarycomputer.microsoft.com/api/stac/v1/",
+    )
     s.search(area)