diff --git a/CHANGELOG.md b/CHANGELOG.md
index 96f56e7..fca29ae 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,19 @@
 # Changelog
 
 All notable changes to this project will be documented in this file.
+## [v2605.0.0]
+## Fixed
+- `FileNotFoundError` for missing local files instead of misleading "cannot detect format"
+- `storage_options` leaking into posix backends (cfgrib, scipy, netcdf4, rasterio), causing TypeError
+- cfgrib .idx files now written to prism cache dir instead of next to the original file
+## Removed
+- line-clearing ANSI escape machinery unreliable across terminals and notebooks
+- logging.basicConfig call from library code
+## Changed
+- detection log messages from INFO to DEBUG
+## Added
+- `XARRAY_PRISM_LOG_LEVEL` env var to control log verbosity
+
 ## [v2603.0.0]
 ## Fixed
 - an issue regading passing the storage_options to aiohttp
diff --git a/README.md b/README.md
index 46afde4..779a31c 100644
--- a/README.md
+++ b/README.md
@@ -176,6 +176,20 @@ xp.clear_cache(max_age_days=0, max_size_gb=0)
 > | TTL (last-access) | 7 days | `XARRAY_PRISM_MAX_AGE_DAYS=N` |
 > | Size cap (LRU) | 10 GB | `XARRAY_PRISM_MAX_SIZE_GB=N` |
 
+### Logging
+
+By default xarray-prism is silent (`WARNING` level). Set `XARRAY_PRISM_LOG_LEVEL` to change verbosity:
+
+```bash
+# Show detection and open steps
+XARRAY_PRISM_LOG_LEVEL=DEBUG python my_script.py
+
+# Suppress everything except errors
+XARRAY_PRISM_LOG_LEVEL=ERROR python my_script.py
+```
+
+Accepted values: `DEBUG`, `INFO`, `WARNING`, `ERROR`, `CRITICAL`.
+
 
 ## Customization
 
diff --git a/src/xarray_prism/__init__.py b/src/xarray_prism/__init__.py
index 56218b5..0577bb2 100644
--- a/src/xarray_prism/__init__.py
+++ b/src/xarray_prism/__init__.py
@@ -13,6 +13,9 @@
 # cfgrib and scipy typically must read the entire file (and build
 # its index) even when only a small subset is requested.
 
+import logging
+import os
+
 from ._cache import cache_info, clear_cache
 from ._detection import (
     detect_engine,
@@ -23,6 +26,18 @@
 from ._registry import registry
 from ._version import __version__  # noqa
 
+_level = getattr(
+    logging,
+    os.environ.get("XARRAY_PRISM_LOG_LEVEL", "WARNING").upper(),
+    logging.WARNING,
+)
+_logger = logging.getLogger("xarray_prism")
+_logger.setLevel(_level)
+if _level < logging.WARNING and not _logger.handlers:
+    _handler = logging.StreamHandler()
+    _handler.setFormatter(logging.Formatter("%(name)s %(levelname)s: %(message)s"))
+    _logger.addHandler(_handler)
+
 __all__ = [
     "PrismBackendEntrypoint",
     "detect_engine",
diff --git a/src/xarray_prism/_cache.py b/src/xarray_prism/_cache.py
index 622c032..e1b03c4 100644
--- a/src/xarray_prism/_cache.py
+++ b/src/xarray_prism/_cache.py
@@ -4,7 +4,6 @@
 
 import logging
 import os
-import sys
 import tempfile
 import time
 from hashlib import md5
@@ -46,7 +45,6 @@ def cache_remote_file(
     engine: str,
     storage_options: Optional[Dict] = None,
     show_progress: bool = True,
-    lines_above: int = 0,
 ) -> str:
     """Cache remote file to local."""
     import fsspec
@@ -60,18 +58,11 @@ def cache_remote_file(
     local_path = cache_root / cache_name
 
     if local_path.exists():
-        if show_progress and lines_above > 0:
-            for _ in range(lines_above):
-                sys.stdout.write("\033[A")
-                sys.stdout.write("\033[K")
-            sys.stdout.flush()
         return _decompress_if_needed(str(local_path))
 
-    extra_lines = 0
     if show_progress:
         fmt = "GRIB" if engine == "cfgrib" else "NetCDF3"
         logger.warning(f"Remote {fmt} requires full file download")
-        extra_lines = 2
 
     fs, path = fsspec.core.url_to_fs(
         uri, **_strip_chaining_options(storage_options or {})
@@ -89,7 +80,7 @@ def cache_remote_file(
             display_name = display_name[:32] + "..."
         desc = f" Downloading {display_name}"
 
-        with ProgressBar(desc=desc, lines_above=lines_above + extra_lines) as progress:
+        with ProgressBar(desc=desc) as progress:
             progress.set_size(size)
             with fs.open(path, "rb") as src, open(local_path, "wb") as dst:
                 while True:
diff --git a/src/xarray_prism/_version.py b/src/xarray_prism/_version.py
index d4d9e4a..fc9d358 100644
--- a/src/xarray_prism/_version.py
+++ b/src/xarray_prism/_version.py
@@ -1,3 +1,3 @@
 """Version information for xarray-prism."""
 
-__version__ = "2603.0.0"
+__version__ = "2605.0.0"
diff --git a/src/xarray_prism/backends/cloud.py b/src/xarray_prism/backends/cloud.py
index 76e7b67..c0838df 100644
--- a/src/xarray_prism/backends/cloud.py
+++ b/src/xarray_prism/backends/cloud.py
@@ -3,13 +3,11 @@
 from __future__ import annotations
 
 import logging
-import sys
 from typing import Any, Dict, Optional
 
 from .._cache import cache_remote_file
 
 logger = logging.getLogger(__name__)
-logging.basicConfig(level=logging.INFO)
 
 
 def open_cloud(
@@ -18,7 +16,6 @@ def open_cloud(
     drop_variables: Optional[Any] = None,
     backend_kwargs: Optional[Dict[str, Any]] = None,
     show_progress: bool = True,
-    lines_above: int = 0,
     **kwargs,
 ) -> Any:
     """Open remote file with detected engine."""
@@ -28,21 +25,11 @@ def open_cloud(
 
     storage_options = kwargs.pop("storage_options", None)
 
-    def _clear_lines():
-        """Clear the detection message lines."""
-        if lines_above > 0:
-            for _ in range(lines_above):
-                sys.stdout.write("\033[A")
-                sys.stdout.write("\033[K")
-            sys.stdout.flush()
-
     bk = backend_kwargs or None
 
     # GRIB / NetCDF3: must download the full file first
     if engine in ("cfgrib", "scipy"):
-        local_path = cache_remote_file(
-            uri, engine, storage_options, show_progress, lines_above
-        )
+        local_path = cache_remote_file(uri, engine, storage_options, show_progress)
         return xr.open_dataset(
             local_path,
             engine=engine,
@@ -53,30 +40,26 @@ def _clear_lines():
 
     # NetCDF4 (OPeNDAP)
     if engine == "netcdf4":
-        ds = xr.open_dataset(
+        return xr.open_dataset(
             uri,
             engine=engine,
             drop_variables=drop_variables,
             backend_kwargs=bk,
             **kwargs,
         )
-        _clear_lines()
-        return ds
 
     # Rasterio: translate storage_options -> GDAL env vars
     if engine == "rasterio":
         from ..utils import sanitize_rasterio_kwargs
 
         with gdal_env(storage_options):
-            ds = xr.open_dataset(
+            return xr.open_dataset(
                 uri,
                 engine=engine,
                 drop_variables=drop_variables,
                 backend_kwargs=bk,
                 **sanitize_rasterio_kwargs(kwargs),
             )
-        _clear_lines()
-        return ds
 
     # Zarr, h5netcdf
     ds = xr.open_dataset(
@@ -91,5 +74,4 @@ def _clear_lines():
         from ..utils import sanitize_dataset_attrs
 
         return sanitize_dataset_attrs(ds)
-    _clear_lines()
     return ds
diff --git a/src/xarray_prism/backends/posix.py b/src/xarray_prism/backends/posix.py
index fd7e67d..b929a11 100644
--- a/src/xarray_prism/backends/posix.py
+++ b/src/xarray_prism/backends/posix.py
@@ -3,6 +3,7 @@
 
 from __future__ import annotations
 
+import os
 from typing import Any, Dict, Optional
 
 
@@ -16,6 +17,20 @@ def open_posix(
     """Open local file with detected engine."""
     import xarray as xr
 
+    # the following posix backends don't accept storage_options
+    _NO_STORAGE_OPTIONS = frozenset({"cfgrib", "scipy", "netcdf4", "rasterio"})
+    if engine in _NO_STORAGE_OPTIONS:
+        kwargs.pop("storage_options", None)
+
+    if engine == "cfgrib":
+        from .._cache import get_cache_dir
+
+        bk = dict(backend_kwargs or {})
+        if "indexpath" not in bk:
+            basename = os.path.basename(uri)
+            bk["indexpath"] = str(get_cache_dir() / f"{basename}.{{short_hash}}.idx")
+        backend_kwargs = bk
+
     if engine == "rasterio":
         from ..utils import sanitize_rasterio_kwargs
 
diff --git a/src/xarray_prism/entrypoint.py b/src/xarray_prism/entrypoint.py
index 336e7f7..d9e942c 100644
--- a/src/xarray_prism/entrypoint.py
+++ b/src/xarray_prism/entrypoint.py
@@ -102,21 +102,17 @@ def open_dataset(
             )
 
         uri = str(filename_or_obj)
-
         is_remote = "://" in uri and not uri.startswith("file://")
-        lines_printed = 0
 
-        if is_remote:
-            logger.info("Detecting format...")
-            sys.stdout.flush()
+        uri_type = detect_uri_type(uri)
+        if uri_type == "posix":
+            posix_path = uri[7:] if uri.startswith("file://") else uri
+            if not os.path.exists(posix_path):
+                raise FileNotFoundError(f"Xarray Prism: file not found: {uri!r}")
 
+        logger.debug("Detecting format for %s", uri)
         engine, uri_type = self._detect(uri, **kwargs)
-
-        if is_remote and engine:
-            logger.info(f"Detected: {engine}")
-            lines_printed = 1
-            sys.stdout.write("\r" + " " * 25 + "\r")
-            sys.stdout.flush()
+        logger.debug("Detected engine=%s uri_type=%s", engine, uri_type)
 
         if engine is None:
             if is_remote:
@@ -187,7 +183,6 @@ def open_dataset(
                 engine=engine,
                 drop_variables=drop_variables,
                 backend_kwargs=backend_kwargs,
-                lines_above=lines_printed,
                 **kwargs,
             )
         else:
diff --git a/src/xarray_prism/utils.py b/src/xarray_prism/utils.py
index 69db7f8..8b4d964 100644
--- a/src/xarray_prism/utils.py
+++ b/src/xarray_prism/utils.py
@@ -30,9 +30,7 @@
 class ProgressBar:
     """Progress bar to display cache download progress."""
 
-    def __init__(
-        self, desc: str = "Downloading", width: int = 40, lines_above: int = 0
-    ):
+    def __init__(self, desc: str = "Downloading", width: int = 40):
         self.desc = desc
         self.width = width
         self._total = 0
@@ -40,7 +38,6 @@ def __init__(
         self._spinner = 0
         self._spinner_chars = "⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏"
         self._last_line_len = 0
-        self._lines_above = lines_above
 
     def set_size(self, size: int) -> None:
         self._total = size if size else 0
@@ -74,12 +71,6 @@ def __enter__(self):
     def __exit__(self, *args):
         # Clear the progress line
         sys.stdout.write("\r" + " " * self._last_line_len + "\r")
-
-        # Clear detection + warning messages
-        for _ in range(self._lines_above):
-            sys.stdout.write("\033[A")
-            sys.stdout.write("\033[K")
-
         sys.stdout.flush()