_____The first storm in the case studies occurred on the 19th-20th of January, 1961, beginning on the eve of John F. Kennedy's inauguration. The storm dumped between 10 to 20+ inches in areas stretching from northern Maryland to southern New Hampshire. This storm was the second of three that hit the area in the winter of '60-'61.

_____There is some evidence that a 1024 mb high pressure core sitting several hundred miles north of the New York/Canada boarder resulted in an instance of cold air damming just prior to the cyclogenesis event, however the extent of the effect that this had on the system is unknown. The surface low moved along a straight path over the Appalachian range as it moved towards the Atlantic Coast on the 19th. This cyclone moved rapidly at a rate near 700 km in a twelve hour period, and this resulted in the snowfall amounts (with the exception of a few isolated areas) being less than 20 inches. This particular cyclone went through a period of rapid deepening from 12Z on the 19th to 00Z on the 20th, and this helped cause a pressure fall of 43 millibars over a twenty-four hour period, far more than enough to classify it as a bomb event. This rapid intensification conincided with a rapidly developing "precipitation shield" that resulted in a dramatic increase in snowfall totals in the following 12 to 24 hour period.

_____A high amplitude ridge sat fairly stationary along the West Coast prior to this event. The trough that was associated with the cyclone was positioned downstream of the ridge and imbedded within a strong flow that extended from central Canada and down through the northern US with a broad ridge extending across the Gulf of Mexico. On the 19th and 20th, an open wave trough moved eastward across the US. As it moved it evolved into a closed-contour center while the associated surface low was rapidly deepening off the East Coast. At 00Z on the 20th of January the geopotential gradients increased at the base of the trough and this coincided with the strong cyclonic development. As the surface low deepened, diffluence occurred along with the development of a negatively tilted trough.

_____At 12Z on the 18th, wind speeds at the 200 and 300 mb levels were found to be near 50 m/s. Twelve hours later, the areas of highest wind speeds increased by 10 m/s and moved eastward and towards the base of the trough. Evidence of a multiple jet streak structure was also found. By 12Z on the 19th, the area of high winds expanded eastwards near a developing ridge axis. Twelve hours later the wind speeds had reached 70 m/s at the 200 mb level as the wavelength of the trough/ridge shortened and the geopotential gradient increased. By 00Z on the 21st the wind speeds were in excess of 90 m/s as the surface low moved to the east of the New England area.

500 mb Heights and Upper-Level Winds