Late season Nor’easter
GOES-16 (GOES-East) Air Mass RGB images (above) include 3-hourly surface analyses of pressure and fronts — which showed the progression of a late-season Nor’easter during the 13 March – 15 March 2023 period. This storm produced heavy snowfall and high winds across much of the Northeast US (including a gust to 81 knots or 93 mph at Mt. Washington NH).As the system was beginning to intensify off the coast of North Carolina on 13 March, 1-minute Mesoscale Domain Sector GOES-16 True Color RGB images from the CSPP GeoSphere site (below) revealed the hazy signature of enhanced solar reflection off an agitated sea surface (where high waves and abundant sea spray were present) — the likely result of a burst of strong middle-tropospheric winds that had descended to the surface (just south of the surface low pressure center). A similar signature of enhanced solar reflection off a highly-agitated sea surface was observed with strong West Atlantic storms in December 2022 and April 2019.
On 14 March, as the storm was slowly pivoting around Buoy 44005 in the Gulf of Maine during the time period shown in GOES-16 “Clean” Infrared Window (10.3 µm) images (above), the buoy wind speed decreased from 37 knots gusting to 45 knots (with a peak hourly gust of 51 knots) at 2150 UTC to just 5 knots gusting to 12 knots (but with a peak hourly gust of 35 knots) at 2350 UTC (below).