Moderate to Severe Turbulence over the High Plains

December 13th, 2019 |

GOES-16 Mid-level (6.9 µm) Water Vapor images, with plots of Pilot Reports of turbulence (cyan and red), Turbulence SIGMETS (red boxes) and RAP40 model isotachs of maximum wind (yellow) [click to play animation | MP4]

GOES-16 Mid-level (6.9 µm) Water Vapor images, with plots of Pilot Reports of turbulence (cyan and red), Turbulence SIGMETS (red boxes) and RAP40 model isotachs of maximum wind (yellow) [click to play animation | MP4]

As a strong 170-knot jet streak (Satellite Liaison Blog) flowed southeastward over the High Plains on 13 December 2019, GOES-16 (GOES-East) Mid-level (6.9 µm) Water Vapor images (above) showed numerous pilot reports of moderate to severe turbulence at altitudes of 26,000-50,000 feet. The Turbulence SIGMETs were issued due to strong speed shear along the poleward (northeast) edge of the jet streak — this speed shear was evident by the closely-spaced isotachs of maximum wind speed from the RAP40 model.

Over southeastern Colorado, one aircraft encountered Severe Turbulence at an altitude of 36,000 feet at 1637 UTC, while another reported Moderate to Severe Turbulence at 37,000 feet at 1645 UTC (due to a mountain wave, which caused fluctuation in airspeed of +/- 20 knots) (below).

GOES-16 Water Vapor (6.9 µm) image with a pilot report of severe turbulence at 36,000 feet [click to enlarge]

GOES-16 Water Vapor (6.9 µm) image with a pilot report of severe turbulence at 36,000 feet [click to enlarge]

GOES-16 Water Vapor (6.9 µm) image with a pilot report of moderate to severe turbulence at 37,000 feet [click to enlarge]

GOES-16 Water Vapor (6.9 µm) image with a pilot report of moderate to severe turbulence at 37,000 feet [click to enlarge]