Storm Summary
Synoptic Overview
As the January 23 storm system and upper-level jet began to lift northeast away from North Carolina,
a second short-wave trough was digging southeastward into the Deep South.
At 00Z on the 24th, a large area of precipitation associated with the departing storm stretched from the North Carolina coast through northern Florida. At around 06Z, an area of convection developed along the Gulf Coast over Louisiana
and Southern Mississippi. By 12Z, the upper-level short-wave had begun to
amplify and become negatively tilted, and a low pressure system formed over northern Florida.
As the deepening upper-level wave drew cold air southward, precipitation began
falling into the relatively dry air airmass over the state, and
surface temperatures fell to below freezing across much of the area. The upper-level support,
coupled with a pre-existing baroclinic zone draped
across the southeast, allowed the surface low to rapidly strengthen off the South Carolina coast.
As the area of new convection moved across the Southeast, it rapidly merged with the developing low pressure, creating
an "instant occlusion" of the storm, which leads to rapid cyclogenesis. Heavy snow began to fall just after midnight in the Raleigh-Durham area on the 25th (see surface observations below).
The low pressure system would eventually deepen to around 986mb and
move up the Atlantic seaboard, spreading snow across much of the Mid-Atlantic and New England by 06Z on the 26th.
Surface Observations at Raleigh-Durham (KRDU)
The intensity of the snowfall, combined with the accumulation and strong winds, caused thousands of business and
residents to be without power for several days. Observations from the Raleigh Durham International show six out
of seven consecutive hours reporting heavy snow (*Note: 11Z Observation unavailable):
KRDU 250551Z 01016G27KT 1/4SM +SN FZFG SCT002 BKN006 OVC011 M02/M02 A2954
KRDU 250651Z 36012G19KT 310V030 1/4SM +SN FZFG OVC002 M02/M02 A2955
KRDU 250751Z 01013G25KT 1/4SM +SN FZFG OVC002 M02/M03 A2953
KRDU 250851Z 36009G19KT 330V040 M1/4SM +SN FZFG SCT002 OVC008 M03/M03 A2951
KRDU 250951Z 36013G29KT 310V030 M1/4SM +SN FZFG SCT002 OVC008 M02/M03 A2950
KRDU 251151Z 35010G21KT 310V050 1SM -SN BR SCT002 OVC009 M02/M03 A2952
KRDU 251251Z 34012G20KT 300V360 1/4SM +SN FZFG SCT002 BKN009 OVC014 M02/M03 A2952
Radar Observations
Heavy precipitation can be seen in the regional radar reflectivity image from 06Z (100 AM) on January 25, 2000 below. A band of high
radar reflectivity indicative of heavy precipitation is shown stretching across North Carolina.
As the storm system intensified and moved up the coast the band evolved and rotated but it
generally remained over central North Carolina resulting in the significant snow accumulations.
A radar loop from 00Z January 24 (700 PM January 23) through 11Z January 26 (600 AM January 26)
shows the evolution of the storm system including the initial storm on January 23, the development
of precipitation across the Gulf Coast states resulting from an intense upper level jet, to the
rapid deepening of the primary storm on January 24 and 25, 2000.
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