diff --git a/.gitignore b/.gitignore
index d248bf98..e450bd8f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,5 @@
 # pixi environments
 .pixi
 .vscode/
+checkpoints/
+lightning_logs/
diff --git a/environment_cpu.yml b/environment_cpu.yml
index db246dba..383d4a1e 100644
--- a/environment_cpu.yml
+++ b/environment_cpu.yml
@@ -24,8 +24,11 @@ dependencies:
   - zarr
   - h3-py
   - numpy
-  - torch_harmonics
+  - pyshtools
+  - gcsfs
+  - pytest
   - pip:
+      - setuptools
       - datasets
       - einops
       - fsspec
@@ -36,3 +39,4 @@ dependencies:
       - click
       - trimesh
       - rtree
+      - torch-harmonics
diff --git a/environment_cuda.yml b/environment_cuda.yml
index 0b86f8fb..e1eb18d4 100644
--- a/environment_cuda.yml
+++ b/environment_cuda.yml
@@ -6,7 +6,7 @@ channels:
   - conda-forge
   - defaults
 dependencies:
-  - pytorch-cuda=12.1
+  - pytorch-cuda
   - numcodecs
   - pandas
   - pip
@@ -25,8 +25,11 @@ dependencies:
   - zarr
   - h3-py
   - numpy
-  - torch_harmonics
+  - pyshtools
+  - gcsfs
+  - pytest
   - pip:
+      - setuptools
       - datasets
       - einops
       - fsspec
@@ -37,3 +40,4 @@ dependencies:
       - click
       - trimesh
       - rtree
+      - torch-harmonics
diff --git a/graph_weather/models/__init__.py b/graph_weather/models/__init__.py
index ace964db..91909420 100644
--- a/graph_weather/models/__init__.py
+++ b/graph_weather/models/__init__.py
@@ -1,6 +1,12 @@
 """Models"""
 
-from .fengwu_ghr.layers import ImageMetaModel, MetaModel, WrapperImageModel, WrapperMetaModel
+from .fengwu_ghr.layers import (
+    ImageMetaModel,
+    LoRAModule,
+    MetaModel,
+    WrapperImageModel,
+    WrapperMetaModel,
+)
 from .layers.assimilator_decoder import AssimilatorDecoder
 from .layers.assimilator_encoder import AssimilatorEncoder
 from .layers.decoder import Decoder
diff --git a/graph_weather/models/fengwu_ghr/__init__.py b/graph_weather/models/fengwu_ghr/__init__.py
new file mode 100644
index 00000000..39b921fd
--- /dev/null
+++ b/graph_weather/models/fengwu_ghr/__init__.py
@@ -0,0 +1,3 @@
+"""Main import for FengWu-GHR"""
+
+from .layers import ImageMetaModel, LoRAModule, MetaModel, WrapperImageModel, WrapperMetaModel
diff --git a/graph_weather/models/fengwu_ghr/layers.py b/graph_weather/models/fengwu_ghr/layers.py
index d129d2dd..38cf43ab 100644
--- a/graph_weather/models/fengwu_ghr/layers.py
+++ b/graph_weather/models/fengwu_ghr/layers.py
@@ -22,6 +22,9 @@ def knn_interpolate(
         squared_distance = (diff * diff).sum(dim=-1, keepdim=True)
         weights = 1.0 / torch.clamp(squared_distance, min=1e-16)
 
+        y_idx, x_idx = y_idx.to(x.device), x_idx.to(x.device)
+        weights = weights.to(x.device)
+
     den = scatter(weights, y_idx, 0, pos_y.size(0), reduce="sum")
     y = scatter(x[x_idx] * weights, y_idx, 0, pos_y.size(0), reduce="sum")
 
@@ -228,6 +231,7 @@ def __init__(
         )
 
     def forward(self, x):
+        assert x.shape[1] == self.channels, "Wrong number of channels"
         device = x.device
         dtype = x.dtype
 
@@ -276,7 +280,7 @@ def __init__(
         super().__init__()
         self.i_h, self.i_w = pair(image_size)
 
-        self.pos_x = torch.tensor(lat_lons)
+        self.pos_x = torch.tensor(lat_lons).to(torch.long)
         self.pos_y = torch.cartesian_prod(
             (torch.arange(-self.i_h / 2, self.i_h / 2, 1) / self.i_h * 180).to(torch.long),
             (torch.arange(0, self.i_w, 1) / self.i_w * 360).to(torch.long),
@@ -344,3 +348,45 @@ def forward(self, x):
         x = rearrange(x, "n (b c) -> b n c", b=b, c=c)
 
         return x
+
+
+class LoRALayer(nn.Module):
+    def __init__(self, linear_layer: nn.Module, r: int):
+        """
+        Initialize LoRALayer.
+
+        Args:
+            linear_layer (nn.Module): Linear layer to be transformed.
+            r (int): rank of the low-rank matrix.
+        """
+        super().__init__()
+        out_features, in_features = linear_layer.weight.shape
+
+        self.A = nn.Parameter(torch.randn(r, in_features))
+        self.B = nn.Parameter(torch.zeros(out_features, r))
+        self.linear_layer = linear_layer
+
+    def forward(self, x):
+        out = self.linear_layer(x) + self.B @ self.A @ x
+        return out
+
+
+class LoRAModule(nn.Module):
+    def __init__(self, model, r=4):
+        """
+        Initialize LoRAModule.
+
+        Args:
+            model (nn.Module): Model to be modified with LoRA layers.
+            r (int, optional): Rank of LoRA layers. Defaults to 4.
+        """
+        super().__init__()
+        for name, layer in model.named_modules():
+            layer.eval()
+            if isinstance(layer, nn.Linear):
+                lora_layer = LoRALayer(layer, r)
+                setattr(model, name, lora_layer)
+        self.model = model
+
+    def forward(self, x):
+        return self.model(x)
diff --git a/tests/test_model.py b/tests/test_model.py
index 94ed991b..9fae0a1d 100644
--- a/tests/test_model.py
+++ b/tests/test_model.py
@@ -252,7 +252,6 @@ def test_image_meta_model():
 
     out = model(image)
     assert not torch.isnan(out).any()
-    assert not torch.isnan(out).any()
     assert out.size() == image.size()
 
 
@@ -275,7 +274,6 @@ def test_wrapper_image_meta_model():
     big_model = WrapperImageModel(model, scale_factor)
     out = big_model(big_image)
     assert not torch.isnan(out).any()
-    assert not torch.isnan(out).any()
     assert out.size() == big_image.size()
 
 
@@ -303,5 +301,34 @@ def test_meta_model():
 
     out = model(features)
     assert not torch.isnan(out).any()
-    assert not torch.isnan(out).any()
     assert out.size() == features.size()
+
+
+def test_wrapper_meta_model():
+    lat_lons = []
+    for lat in range(-90, 90, 5):
+        for lon in range(0, 360, 5):
+            lat_lons.append((lat, lon))
+
+    batch = 2
+    channels = 3
+    image_size = 20
+    patch_size = 4
+    scale_factor = 3
+    model = MetaModel(
+        lat_lons,
+        image_size=image_size,
+        patch_size=patch_size,
+        depth=1,
+        heads=1,
+        mlp_dim=7,
+        channels=channels,
+        dim_head=64,
+    )
+
+    big_features = torch.randn((batch, len(lat_lons), channels))
+    big_model = WrapperMetaModel(lat_lons, model, scale_factor)
+    out = big_model(big_features)
+
+    assert not torch.isnan(out).any()
+    assert out.size() == big_features.size()
diff --git a/train/era5.py b/train/era5.py
new file mode 100644
index 00000000..ab5eee2d
--- /dev/null
+++ b/train/era5.py
@@ -0,0 +1,192 @@
+from pathlib import Path
+
+import numpy as np
+import pytorch_lightning as pl
+import torch
+import xarray
+from einops import rearrange
+from pytorch_lightning.callbacks import ModelCheckpoint
+from torch.utils.data import DataLoader, Dataset
+
+from graph_weather.models import MetaModel
+from graph_weather.models.losses import NormalizedMSELoss
+
+
+class LitFengWuGHR(pl.LightningModule):
+    """
+    LightningModule for graph-based weather forecasting.
+
+    Attributes:
+        model (GraphWeatherForecaster): Graph weather forecaster model.
+        criterion (NormalizedMSELoss): Loss criterion for training.
+        lr : Learning rate for optimizer.
+
+    Methods:
+        __init__: Initialize the LitFengWuGHR object.
+        forward: Forward pass of the model.
+        training_step: Training step.
+        configure_optimizers: Configure the optimizer for training.
+    """
+
+    def __init__(
+        self,
+        lat_lons: list,
+        *,
+        channels: int,
+        image_size,
+        patch_size=4,
+        depth=5,
+        heads=4,
+        mlp_dim=5,
+        feature_dim: int = 605,  # TODO where does this come from?
+        lr: float = 3e-4,
+    ):
+        """
+        Initialize the LitFengWuGHR object with the required args.
+
+        Args:
+            lat_lons : List of latitude and longitude values.
+            feature_dim : Dimensionality of the input features.
+            aux_dim : Dimensionality of auxiliary features.
+            hidden_dim : Dimensionality of hidden layers in the model.
+            num_blocks : Number of graph convolutional blocks in the model.
+            lr (float): Learning rate for optimizer.
+        """
+        super().__init__()
+        self.model = MetaModel(
+            lat_lons,
+            image_size=image_size,
+            patch_size=patch_size,
+            depth=depth,
+            heads=heads,
+            mlp_dim=mlp_dim,
+            channels=channels,
+        )
+        self.criterion = NormalizedMSELoss(
+            lat_lons=lat_lons, feature_variance=np.ones((feature_dim,))
+        )
+        self.lr = lr
+        self.save_hyperparameters()
+
+    def forward(self, x):
+        """
+        Forward pass .
+
+        Args:
+            x (torch.Tensor): Input tensor.
+
+        Returns:
+            torch.Tensor: Output tensor.
+        """
+        return self.model(x)
+
+    def training_step(self, batch, batch_idx):
+        """
+        Training step.
+
+        Args:
+            batch (array): Batch of data containing input and output tensors.
+            batch_idx (int): Index of the current batch.
+
+        Returns:
+            torch.Tensor: Loss tensor.
+        """
+        x, y = batch[:, 0], batch[:, 1]
+        if torch.isnan(x).any() or torch.isnan(y).any():
+            return None
+        y_hat = self.forward(x)
+        loss = self.criterion(y_hat, y)
+        self.log("loss", loss, prog_bar=True)
+        return loss
+
+    def configure_optimizers(self):
+        """
+        Configure the optimizer.
+
+        Returns:
+            torch.optim.Optimizer: Optimizer instance.
+        """
+        return torch.optim.AdamW(self.parameters(), lr=self.lr)
+
+
+class Era5Dataset(Dataset):
+    """Era5 dataset."""
+
+    def __init__(self, xarr, transform=None):
+        """
+        Arguments:
+            #TODO
+        """
+        ds = np.asarray(xarr.to_array())
+        ds = torch.from_numpy(ds)
+        ds -= ds.min(0, keepdim=True)[0]
+        ds /= ds.max(0, keepdim=True)[0]
+        ds = rearrange(ds, "C T H W -> T (H W) C")
+        self.ds = ds
+
+    def __len__(self):
+        return len(self.ds) - 1
+
+    def __getitem__(self, index):
+        return self.ds[index : index + 2]
+
+
+if __name__ == "__main__":
+
+    ckpt_path = Path("./checkpoints")
+    patch_size = 4
+    grid_step = 20
+    variables = [
+        "2m_temperature",
+        "surface_pressure",
+        "10m_u_component_of_wind",
+        "10m_v_component_of_wind",
+    ]
+
+    channels = len(variables)
+    ckpt_path.mkdir(parents=True, exist_ok=True)
+
+    reanalysis = xarray.open_zarr(
+        "gs://gcp-public-data-arco-era5/ar/full_37-1h-0p25deg-chunk-1.zarr-v3",
+        storage_options=dict(token="anon"),
+    )
+
+    reanalysis = reanalysis.sel(time=slice("2020-01-01", "2021-01-01"))
+    reanalysis = reanalysis.isel(
+        time=slice(100, 107), longitude=slice(0, 1440, grid_step), latitude=slice(0, 721, grid_step)
+    )
+
+    reanalysis = reanalysis[variables]
+    print(f"size: {reanalysis.nbytes / (1024 ** 3)} GiB")
+
+    lat_lons = np.array(
+        np.meshgrid(
+            np.asarray(reanalysis["latitude"]).flatten(),
+            np.asarray(reanalysis["longitude"]).flatten(),
+        )
+    ).T.reshape((-1, 2))
+
+    checkpoint_callback = ModelCheckpoint(dirpath=ckpt_path, save_top_k=1, monitor="loss")
+
+    dset = DataLoader(Era5Dataset(reanalysis), batch_size=10, num_workers=8)
+    model = LitFengWuGHR(
+        lat_lons=lat_lons,
+        channels=channels,
+        image_size=(721 // grid_step, 1440 // grid_step),
+        patch_size=patch_size,
+        depth=5,
+        heads=4,
+        mlp_dim=5,
+    )
+    trainer = pl.Trainer(
+        accelerator="gpu",
+        devices=-1,
+        max_epochs=100,
+        precision="16-mixed",
+        callbacks=[checkpoint_callback],
+        log_every_n_steps=3,
+    )
+
+    trainer.fit(model, dset)
+
+    torch.save(model.model.state_dict(), ckpt_path / "best.pt")
diff --git a/train/lora.py b/train/lora.py
new file mode 100644
index 00000000..f829c797
--- /dev/null
+++ b/train/lora.py
@@ -0,0 +1,165 @@
+from pathlib import Path
+
+import numpy as np
+import pytorch_lightning as pl
+import torch
+import torch.nn as nn
+import xarray
+from einops import rearrange
+from pytorch_lightning.callbacks import ModelCheckpoint
+from torch.utils.data import DataLoader, Dataset
+
+from graph_weather.models import LoRAModule, MetaModel
+from graph_weather.models.losses import NormalizedMSELoss
+
+
+class LitLoRAFengWuGHR(pl.LightningModule):
+    def __init__(
+        self,
+        lat_lons: list,
+        single_step_model_state_dict: dict,
+        *,
+        time_step: int,
+        rank: int,
+        channels: int,
+        image_size,
+        patch_size=4,
+        depth=5,
+        heads=4,
+        mlp_dim=5,
+        feature_dim: int = 605,  # TODO where does this come from?
+        lr: float = 3e-4,
+    ):
+        super().__init__()
+        assert (
+            time_step > 1
+        ), "Time step must be greater than 1. Remember that 1 is the simple model time step."
+        ssmodel = MetaModel(
+            lat_lons,
+            image_size=image_size,
+            patch_size=patch_size,
+            depth=depth,
+            heads=heads,
+            mlp_dim=mlp_dim,
+            channels=channels,
+        )
+        ssmodel.load_state_dict(single_step_model_state_dict)
+        self.models = nn.ModuleList(
+            [ssmodel] + [LoRAModule(ssmodel, r=rank) for _ in range(2, time_step + 1)]
+        )
+        self.criterion = NormalizedMSELoss(
+            lat_lons=lat_lons, feature_variance=np.ones((feature_dim,))
+        )
+        self.lr = lr
+        self.save_hyperparameters()
+
+    def forward(self, x):
+        ys = []
+        for t, model in enumerate(self.models):
+            x = model(x)
+            ys.append(x)
+        return torch.stack(ys, dim=1)
+
+    def training_step(self, batch, batch_idx):
+        if torch.isnan(batch).any():
+            return None
+        x, ys = batch[:, 0, ...], batch[:, 1:, ...]
+
+        y_hat = self.forward(x)
+        loss = self.criterion(y_hat, ys)
+        self.log("loss", loss, prog_bar=True)
+        return loss
+
+    def configure_optimizers(self):
+        return torch.optim.AdamW(self.parameters(), lr=self.lr)
+
+
+class Era5Dataset(Dataset):
+
+    def __init__(self, xarr, time_step=1, transform=None):
+        assert time_step > 0, "Time step must be greater than 0."
+        ds = np.asarray(xarr.to_array())
+        ds = torch.from_numpy(ds)
+        ds -= ds.min(0, keepdim=True)[0]
+        ds /= ds.max(0, keepdim=True)[0]
+        ds = rearrange(ds, "C T H W -> T (H W) C")
+        self.ds = ds
+        self.time_step = time_step
+
+    def __len__(self):
+        return len(self.ds) - self.time_step
+
+    def __getitem__(self, index):
+        return self.ds[index : index + time_step + 1]
+
+
+if __name__ == "__main__":
+
+    ckpt_path = Path("./checkpoints")
+    ckpt_name = "best.pt"
+    patch_size = 4
+    grid_step = 20
+    time_step = 2
+    rank = 4
+    variables = [
+        "2m_temperature",
+        "surface_pressure",
+        "10m_u_component_of_wind",
+        "10m_v_component_of_wind",
+    ]
+
+    ###############################################################
+
+    channels = len(variables)
+    ckpt_path.mkdir(parents=True, exist_ok=True)
+
+    reanalysis = xarray.open_zarr(
+        "gs://gcp-public-data-arco-era5/ar/full_37-1h-0p25deg-chunk-1.zarr-v3",
+        storage_options=dict(token="anon"),
+    )
+
+    reanalysis = reanalysis.sel(time=slice("2020-01-01", "2021-01-01"))
+    reanalysis = reanalysis.isel(
+        time=slice(100, 111), longitude=slice(0, 1440, grid_step), latitude=slice(0, 721, grid_step)
+    )
+
+    reanalysis = reanalysis[variables]
+    print(f"size: {reanalysis.nbytes / (1024 ** 3)} GiB")
+
+    lat_lons = np.array(
+        np.meshgrid(
+            np.asarray(reanalysis["latitude"]).flatten(),
+            np.asarray(reanalysis["longitude"]).flatten(),
+        )
+    ).T.reshape((-1, 2))
+
+    checkpoint_callback = ModelCheckpoint(dirpath=ckpt_path, save_top_k=1, monitor="loss")
+
+    dset = DataLoader(Era5Dataset(reanalysis, time_step=time_step), batch_size=10, num_workers=8)
+
+    single_step_model_state_dict = torch.load(ckpt_path / ckpt_name)
+
+    model = LitLoRAFengWuGHR(
+        lat_lons=lat_lons,
+        single_step_model_state_dict=single_step_model_state_dict,
+        time_step=time_step,
+        rank=rank,
+        ##########
+        channels=channels,
+        image_size=(721 // grid_step, 1440 // grid_step),
+        patch_size=patch_size,
+        depth=5,
+        heads=4,
+        mlp_dim=5,
+    )
+    trainer = pl.Trainer(
+        accelerator="gpu",
+        devices=-1,
+        max_epochs=100,
+        precision="16-mixed",
+        callbacks=[checkpoint_callback],
+        log_every_n_steps=3,
+        strategy="ddp_find_unused_parameters_true",
+    )
+
+    trainer.fit(model, dset)