Wednesday, November 24, 2010

Deployment #3 underway!

The UND and DOW radars have been operating for the past several hours scanning the snowband in the Red River Valley.  During the passage of the band, the DOW reported low visibilities with moderate to heavy snowfall. 

- The DOW team

DOW radar animations from deployments #1 and #2

DOW radar animations from the first two deployments have been posted to youtube.  Make sure to check them out in HD so you can see all of the fine-scale features!

Deployment #1 (Nov. 20-21, 2010)

Deployment #2 (Nov. 22-23, 2010)

Wedneday - Thursday Forecast

***Another prolonged snow event to impact the the region today and Thursday***

Cyclogenesis will continue to slowly occur over the high plains of Nebraska. The sub-tropical jet, oriented from Arizona to Maine, will force the weak area of low pressure into the Northern Plains during the day today. But, the low pressure system will be lacking the divergence needed in the jet, either from being located in the right entrance or left exit regions, to allow for deep cyclogenesis. The 500 mb trough will be in phase with the surface low, trailing approx 9 hours behind. As the 500 mb trough tracks eastward during the day, the gradient aloft will tighten, and thus increasing the amount of vorticity present from speed and curvature. This, combined with warm-air advection at 850 mb, will provide for wide spread snow across the domain. But, with a lack of an abundant moisture source, it appears the heaviest snow rates will stay to the east and a prolonged period of light snow will persist through the day in the forecast domain. Activity will begin to taper off Thursday morning as the low pressure center begins to move into SW Ontario, but wrap around snow showers will likely be seen through out the day on Thursday. When everything is said and done, new snow accumulations of 2-4 inches, with locally higher amounts, can be expected through out the SNOwD UNDER domain. The biggest difference between this storm and first storm, will be the winds at the surface. Winds on Wednesday are expected to be around 10-20 kts with gusts near 30 kts. As the low pulls away, sustained winds are forecast to be 20-30 kts, with higher gusts. Thus, visibilities will be reduce to 1/4 or less at times creating periodic Blizzard conditions.

***There will not be a forecast briefing Thursday morning.***