Windows + virtualenv + pip + NumPy (problems when installing NumPy)

On Windows, I normally just use the binary installer, but I would like to install NumPy only in a virtualenv this time, so I created a virtual env:

virtualenv --no-site-packages --distribute summary_python
cd summary_python/Scripts
activate.bat

Then I tried to install NumPy

pip install numpy

And I get an error. My pip.log is pasted below:

Downloading/unpacking numpy
  Running setup.py egg_info for package numpy
    non-existing path in 'numpy\\distutils': 'site.cfg'
    F2PY Version 2
    blas_opt_info:
    blas_mkl_info:
      libraries mkl,vml,guide not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries mkl,vml,guide not found in C:\
      NOT AVAILABLE

    atlas_blas_threads_info:
    Setting PTATLAS=ATLAS
      libraries ptf77blas,ptcblas,atlas not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries ptf77blas,ptcblas,atlas not found in C:\
      NOT AVAILABLE

    atlas_blas_info:
      libraries f77blas,cblas,atlas not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries f77blas,cblas,atlas not found in C:\
      NOT AVAILABLE

    blas_info:
      libraries blas not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries blas not found in C:\
      NOT AVAILABLE

    blas_src_info:
      NOT AVAILABLE

      NOT AVAILABLE

    lapack_opt_info:
    lapack_mkl_info:
    mkl_info:
      libraries mkl,vml,guide not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries mkl,vml,guide not found in C:\
      NOT AVAILABLE

      NOT AVAILABLE

    atlas_threads_info:
    Setting PTATLAS=ATLAS
      libraries ptf77blas,ptcblas,atlas not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries lapack_atlas not found in c:\Users\fname.lname\Documents\summary_python\lib
      libraries ptf77blas,