diff --git a/README.md b/README.md
index 2bf13ce552..8a3ee13506 100644
--- a/README.md
+++ b/README.md
@@ -54,6 +54,9 @@ run image, then you could add something like the following to the
 
 Then run `make lock_deps` to update the `constraints.txt` file.
 
+This currently requires `pip` version < 20.3. The latest version 20.3 does not work with 
+the automatically generated `constraints.txt` because it contains extras.
+
 ## The "fv3net" environment
 
 The package `conda-lock` is used to ensure deterministic builds anaconda
diff --git a/docker/prognostic_run/Dockerfile b/docker/prognostic_run/Dockerfile
index e1a6d9b293..cf14c0380c 100644
--- a/docker/prognostic_run/Dockerfile
+++ b/docker/prognostic_run/Dockerfile
@@ -38,7 +38,7 @@ COPY docker/prognostic_run/requirements.txt /tmp/requirements.txt
 COPY constraints.txt /tmp/constraints.txt
 
 RUN pip3 install wheel && \
-    pip3 install --upgrade pip && \
+    pip3 install --upgrade pip==20.2.4 && \
     pip3 install --no-cache-dir -c /tmp/constraints.txt -r /tmp/requirements.txt && \
     ln -s /bin/python3 /bin/python && \
     ln -s /bin/pip3 /bin/pip