A Moderate Risk (Level 4 of 5) has been issued for the likelihood of numerous severe thunderstorms today from parts of the mid Mississippi, Ohio, and Tennessee Valleys into the southern Plains. Strong tornadoes, very large hail, and damaging winds are possible. A Moderate Risk Excessive Rainfall Outlook (Level 3 of 4) includes portions of the Ohio and Tennessee Valleys where flooding is possible. Read More >
Overview
On the morning of December 31, 2006 low pressure was located over south-central Iowa, which deepened over the next 12 hours and moved northeast into Wisconsin. Heavy snow fell in the afternoon from Cambridge through the western suburbs of the Twin Cities, as well as to Fairmont and Blue Earth. Snowfall rates were up to 2 inches per hour and total snowfall was 8-10 inches from the western suburbs of the Twin Cities through Mankato and Blue Earth. Snowfall decreased by early evening over eastern Minnesota.Snowfall Totals
Total snowfall ranged from 8-10 inches from the western suburbs of the Twin Cities through Blue Earth.
 |
Radar:
 |
 |
 |
 |
| 6 hr precip forecast from Dec 31 12Z NAM run | Reflectivity at 16:06Z on Dec 31 | Reflectivity at 18:03Z on Dec 31 | Reflectivity at 20:04Z on Dec 31 |
Environment
An area of low pressure was located over south-central Iowa at 12Z, which then deepened over the next 12 hours and moved northeast into Wisconsin. The region that received the heaviest snowfall was between the left exit region of a 250 mb jet in Illinois and the right entrance region of a 250 mb jet north of Minnesota. The December 31 12Z NAM run showed significant forcing and instability over south-central Minnesota. Also, the 12Z sounding showed a high precipitable water value and deep southerly flow, which provided ideal conditions for snowfall. The 0Z sounding showed a lower temperature profile and wind shift after the low had passed.
 |
 |
 |
| Mean Sea Level Pressure (mb) at 12Z | MSLP (mb) at 15Z | MSLP (mb) at 18Z |
 |
 |
 |
| MSLP (mb) at 21Z | MPX 12Z sounding | MPX 0Z sounding |
 |
 |
|
| NAM differential layer divergence at 21Z | Satellite imagery showing deformation zone at 20:45Z |
 |
Media use of NWS Web News Stories is encouraged! Please acknowledge the NWS as the source of any news information accessed from this site. |
|
Follow us on Twitter
Follow us on Facebook
Follow us on YouTube
MPX RSS Feed