Moderate to Severe Turbulence over the High Plains
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).