From d97de91978b0893fe00d50e90319c86cf16bc77b Mon Sep 17 00:00:00 2001 From: Graham McIntire Date: Tue, 31 Mar 2026 09:27:23 -0500 Subject: [PATCH] Add meteorologist feedback on model choice to RRFS doc --- docs/RRFS.md | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/docs/RRFS.md b/docs/RRFS.md index 50236fd5..eda34447 100644 --- a/docs/RRFS.md +++ b/docs/RRFS.md @@ -78,6 +78,27 @@ When RRFS full output becomes available, key advantages would be: - Potentially improved boundary layer and moisture forecasts from the FV3 dynamic core - Longer forecast horizon for propagation prediction +## Meteorologist Feedback (March 2026) + +From a meteorologist familiar with Gulf region propagation: + +**Model choice validation:** +- HRRR is confirmed as the best short-term (0-48h) choice for low-level inversions and water vapor content. Higher vertical resolution in the boundary layer and tighter grid spacing give it the best handle on moisture — critical since humidity is our highest-weighted scoring factor (20%). +- **NAM should be avoided** — substantially over-estimates low-level water content, especially in the western Gulf region. Over-does fog and water vapor discontinuities. Would produce false-positive ducting predictions in exactly the areas where ducting matters most. +- **GFS is better for days 2-5** forecasts, with a more pessimistic (and more correct) stance on moisture. Worth considering if we add a multi-day propagation forecast view. + +**RRFS transition notes:** +- HRRR will be operationally replaced by RRFS in the next few years +- The meteorologist expects RRFS files may use netCDF format (current experimental output on S3 is GRIB2 — the full operational output format may differ) +- The transition should be "fairly straightforward" — the scoring algorithm itself won't change, only the data ingestion layer +- RRFS is already available experimentally but (as documented above) the public output lacks the fields we need + +**Implications for our architecture:** +- Keep HRRR as primary source — validated by domain expert +- Don't use NAM for anything moisture-related +- The `Propagation.Scorer` module is data-source-agnostic by design — when RRFS becomes available, only the fetch/extraction layer needs to change +- If we add forecast beyond 48h, consider GFS as a supplementary source for days 2-5 + ## References - AWS S3: `s3://noaa-rrfs-pds/` - NOAA RRFS: https://gsl.noaa.gov/focus-areas/unified_forecast_system/rrfs