30-second imagery of mountain waves over the Mid-Atlantic states
Overlapping 1-minute Mesoscale Domain Sectors provided GOES-16 (GOES-East) imagery at 30-second intervals over the Mid-Atlantic states on 20 January 2023 — and Mid-level Water Vapor (6.9 µm) images (above) revealed widespread mountain waves east of the Appalachians (produced by strong westerly flow interacting with the terrain). There were numerous pilot reports of light to moderate turbulence associated with these mountain waves.The 1200 UTC Water Vapor image with plots of rawinsonde sites (below) indicated that Sterling, Virginia KLWX (which replaced the Washington-Dulles site KIAD) was located within the region of drier air where mountain waves were prevalent at that time.
Plots of GOES-16 Water Vapor spectral band (08, 09 and 10) weighting functions calculated using 1200 UTC rawinsonde data from Washington-Dulles, Virginia (KIAD) are shown below — due to the presence of dry air throughout the middle and upper troposphere over that location (Skew-T plot), the water vapor weighting functions were shifted to lower altitudes; the peak of the 6.9 µm (Band 09) weighting function was at the 617.5 hPa pressure level, with significant upwelling radiation contributions originating from as low as the 700 hPa level. 30-second GOES-16 “Red” Visible (0.64 µm) images are shown below.