Dangerous Cold Weather for Most of the Country; Rare Winter Storm for the South; Fire Weather Concerns for Southern California

Arctic air will filter south and east through early this week. As this cold air moves across the South, a rare winter storm is forecast to develop from Texas, Gulf Coast States into the Southeast through early this week. Several new daily record low temperatures are expected, including new record-low maximum temperatures. For Southern California, fire weather concerns increase this week. Read More >

February 4, 2006
Winter Weather Event Review
Section 4: Mesoscale Review

Back to the main event page for February 4, 2006

Section 1 -- Section 2 -- Section 3 -- Section 4 -- Section 5 -- Section 6

While some favorable characteristics existed for banding all of the attributes necessary for development were not present. The 700 mb trough was initially an open wave which deepened and closed off over Ohio on Saturday, February 4 . This event also lacked the dual upper level jet structure. Although the classic potential for banding was not strongly indicated, the potential for enhanced forcing was indicated. Figure 12 shows an axis of 700 mb deformation and 2D frontogenesis over the western portion of the CWA at 12 UTC Saturday. By 18 UTC the 700mb low was closing off and this favorable frontogenesis was over the northwest and by 00 UTC this potential for enhanced lift had shifted north out of the CWA. Figure 13 shows a cross-sectional view northwest-southeast slice through the core of the mid-level frontogenesis at 18 UTC. Although lift is indicated in the zone of preferred dendritic growth, the best upward vertical motion is above the favored thermal ribbon.