Update history for SPC HREF Ensemble Viewer
- New products: time-min updraft helicity. Ensemble minimum and neighborhood probability of magnitude threshold exceedance are plotted. Note that all HREF members now display time-min UH (from mid-June 2019 onward).
- New products: combined time-max/min updraft helicity products. Ensemble min and max are plotted together with separate color tables. Neighborhood probabilities are calculated for exceeding magnitude thresholds that are different for time-max vs. time-min (thresholds for max are currently larger than min by a factor of 2.14 based on preliminary hail verification statistics; small changes are possible in the future).
- New product: precipitable water (PW) mean and threshold exceedance probabilities.
- New product: maximum wind gust (ensemble min/mean/max).
- New product: combined probabilities of high wind and low visibility coinciding with snow to highlight blizzard potential.
- Ensemble mean storm motion vector overlay available for PW products and calibrated thunder guidance.
- Ensemble max reflectivity overlay available for PW products.
- Color table for 10-m AGL wind speed extended downward to shade values as low as 10 mph.
- New GIS underlay: terrain.
- Add two new ensemble members: HRRR and HRRR -6h.
- Extend HREF forecasts to 48-h lead time (some members drop out late in forecast; see "HREF members" link on right menu for details).
- New product: member viewer for composite reflectivity with 4-h max and min 2-5 km UH tracks. Minimum UH is unavailable on NAM Nest and HRW NMMB members as of March 2019, but may be added soon.
- New products: freezing rain QPF and FRAM-based accretion estimate.
- New product: ensemble mean cloud cover for low-, mid-, and high-level clouds.
- Several additional thresholds added for (2-m RH, 10-m hourly max wind) combined probabilities.
- Ensemble max 2-5 km UH contours available as overlay on some environmental fields (e.g., CAPE).
- Introduce new UI to toggle between SPC outlook overlay products and issuance times. All D1 and D2 convective and fire outlooks now available.
- NWS TOR/SVR warnings available as verification for 4-h and 24-h products.
- Replace rollover buttons for forecast times with slider bar.
- "Other Overlays" (GIS, SPC Outlooks, Verification) toggled on by user remain active after new page load.
- Some fields reorganized into member-viewer style UI: multiple exceedance probability thresholds combined into "threshold probs" suites (QPF, snowfall, SBCAPE, etc.), plus ensemble min/mean/max suites added for SBCAPE, 2-m RH, and 10-m hourly max wind.
- New products: rolling 4-h windows for many time-maximum field products (updraft helicity, updraft, 10-m AGL wind speed, and reflectivity). The rolling 4-h windows replace the sequence of 3-h windows previously plotted.
- New products: Fixed-Layer STP mean, P[>1], and P[>3]. Fixed Layer STP formulation is from Gallo et al. (2018).
- New products: QPF gridpoint probability for 1-h P[>1"]; 6-h P[>1"]; 6-h P[>2"]; and 6-h P[>3"].
- New product: updraft helicity member viewer. Some fields on this product are currently unavailable for NAM Nest and HRW NMMB members, but will be included in the future.
- Add 700-500 mb lapse rate (contours, transparent fill) as optional overlay for 700 mb product.
- Add surface based CAPE (contours) as optional overlay for 0-1 km and 0-3 km SRH products.
- Add surface based CIN (contours, hatching) as optional overlay for SBCAPE products.
- Add ensemble mean 2-m AGL temperature (contours at 50°F and 60°F) as optional overlays for Fosberg products.
- Change color table for 1-h mean snowfall product.
- Add hotkeys: J and L for changing forecast times, K and I for changing members in member viewer (existing hotkeys are unchanged).
- Initial site launch coinciding with HREFv2 operational implementation.