... November 28 2006 Winter Weather Event ...

Event Overview

This weather system provided many challenges right up until the event. Abundant moisture was present for the low pressure that tracked from Wyoming into south-central South Dakota into southeastern North Dakota then into the Minnesota arrowhead region. East of  the low pressure system, thunderstorms moved from southern Minnesota into Wisconsin , and on the backside of the low snow fell in the western/central Dakotas . There was a report of thundersnow in Pine River, Minnesota during the early morning hours on Tuesday. Once the low moved into western Minnesota , snow fell in northeastern North Dakota , with freezing rain falling in the Baudette and Roseau areas where around one half inch of ice accumulated before temperatures rose above freezing later on Tuesday afternoon. The low track is shown below in Images section. 

Snowfall accumulations ranged from 2-4 inches in far northeastern North Dakota to 0.8 inches in Grand Forks . Maximum temperatures were highly variable with the middle 50s in Iowa Tuesday afternoon and -13F in Cutbank, Montana . This large temperature and moisture contrast (Images below) (dewpoints of 55 in Iowa/southern Minnesota and -20 in north-central Montana) coupled with a  strong upper-level disturbance provided the needed ingredients for a winter weather event.

 

If more phasing occurred between the upper and lower level systems, this storm could have been much worse given the very large temperature contrast associated with the low pressure area.  When a system phases, both the upper and lower-level features act together to rapidly strengthen a storm. The end result would have been  a significantly stronger storm with more extensive precipitation and stronger winds.

Snowfall Map

Snow Map
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Images

 

Radar Image
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Radar reflectivity at 959am

IR sat
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Infrared Satellite at 645am 
Temp Gradient
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Temperatures at 1pm  
SFC Map 12Z
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Sfc Pres/Tmp Advection 6AM
SFC Map 18Z
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Sfc Pres/Tmp Advection 12PM
SFC Map 21Z
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Sfc Pres/Tmp Advection 3PM

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