2019 Impact Stories

30 June 2019 – Midwest derecho with many high wind reports from WI/MN to IL/IN/KY.

The HRRR did a very good job of predicting this long track bow echo system that moved southeastward across the Midwest producing many reports of destructive high winds.

20-21 October 2019 (in local time evening of 20 October) – Dallas area tornadoes.

At least 2 long-track tornadoes move across the Dallas area as supercells form well ahead of a well-predicted squall line associated with a cold front. The HRRR did give an earlier forecast of tornadic storm potential for Dallas. We attribute the better forecast (we believe anyways) to the improved data assimilation system in the new HRRR.

16 December 2019 – Southeast U.S. tornado outbreak

Several long-track supercell tornadoes. The HRRR had good lead times for long track supercells, as well as a consistent set of forecasts as the event evolved.

13 March 2019 – “Bomb cyclone”

This storm set the record for the lowest surface pressure in Colorado. The HRRR forecasts were good in showing the potential for very strong winds, the heavy snow to the east of Denver, and the “snow hole” that was over Boulder.

14 April 2019 – Historic late season snowfall in the Midwest

A late-season storm brought a swath of snow from northeastern Missouri to southeastern Wisconsin, bringing snowfalls in some areas (including Chicago) that ranked in the top few late-season events. The HRRR did a good job of predicting the snow threat, which was tricky for operational forecasters to convey for this storm. The improved variable snowfall ratio method in the HRRR gave a much better prediction of snow amounts.

27-30 October 2019 – Southern CA high winds and associated wildfires

The HRRR model made accurate forecasts of high Santa Ana winds that produced dangerous fire weather conditions in Southern California. Both timing and location of the strong winds were important aspects of the HRRR forecasts.