December 17-20th 2009 Mississippi Valley/Ohio Valley/Southeast/Mid-Atlantic/Northeast Winter Storm

Thursday-Sunday, Mississippi Valley/Ohio Valley/Southeast/Mid-Atlantic/Northeast Winter Storm

A storm system will move from the Gulf of Mexico up the East Coast from Thursday into Sunday. Copious amounts of moisture from both the Gulf and the Atlantic, along with cold air being brought into the storm from the north, and a track up the coast will create the potential for heavy snow on the northwest side of the storm across portions of the Mid-Mississippi Valley, Ohio Valley, Appalachians, Mid-Atlantic, and Northeast. Accumulations are likely within this corridor including the cities of Boston, New York, Philadelphia, and Washington D.C. The heaviest accumulations will be across portions of the Southern/Central Appalachians up into the Mid-Atlantic where over 12″ of snow will be likely. During the height of the storm, snowfall rates will likely exceed 1″ per hour across portions of the Appalachians and Mid-Atlantic. A more detailed look at potential snowfall amounts can be seen in the snowfall map for this system, which can be found below.

Friday, December 18th 2009 Weather Outlook

Friday’s Weather Outlook; Southeast System, Mid-Mississippi Valley System, Northwest System

On Friday, a system will push through the Southeast, while a system pushes through the Mid-Mississippi Valley, and a system continues to affect the Northwest. Showers and storms will be likely in portions of the Southeast, as a system pushes up the Coast. Given the avaliable instibility and dynamics, a few storms may become severe across portions of the Southeast. The main threats from any storms that become severe, will be damaging winds, hail, and an isolated tornado. On the backside of the system, snow will be likely across portions of the Appalachians, Tennesse Valley, and Mid-Atlantic, with accumulations being likely. In the Mid-Mississippi Valley, a weak system will push through the area. Snow will be likely along and north of the track of the system in the Mid-Missisisppi Valley and Ohio Valley, with accumulations being possible. In the Northwest, a system will continue to effect the area. Rain will be likely in the lower elevations and along the coast, with accumulating snow possible in portions of the Cascades. Below are the thunderstorm and snowfall outlooks for Friday.

Thursday, December 17th 2009 Weather Outlook

Thursday’s Weather Outlook; Gulf Coast System, Central Plains System, Northwest System

On Thursday, a system will push along the Gulf Coast, while a system pushes through the Central states, and a system pushes towards the Northwest. Showers and storms will be likely along the Gulf Coast, as a developing system pushes across the area. Given the avaliable instibility and dynamics, a few storms may become severe along the Gulf Coast. The main threats from any storms that become severe, will be damaging winds and hail. In the Central Plains, a weak system will develop. Showers will be possible across portions of the area, associated with this system. Snow may begin to develop across Iowa, Wisconsin, Missouri, and Illinois late Thursday night or Friday Morning. Some accumulation will be possible. In the Northwest, another system will push into the area bringing the chance of rain to the lower elevations, and accumulating snow to portions of the Cascades and Rockies. Below are the thunderstorma nd snowfall outlooks for Thursday.

Wednesday, December 16th 2009 Weather Outlook

Wednesday’s Weather Outlook; Gulf Coast System, Northern Plains System, Northwest System

On Wednesday, a system will begin to develop in the Gulf, while a system effects the Northern Plains, and a system continues to effect the Northwest. Showers and storms will be likely along the western portions of the Gulf Coast, as a new system begins to develop in the Gulf. Snow will be possible in portions of the Northern Plains and Northern Midwest, associated with a weak system pushing through Southern Canada. In the Northwest, a system will continue to effect the area. Rainw ill be likely along the coast and in lower elevations. While accumulating snow will be likely in most of the interior, Cascades, and Rockies. Below are the thunderstorm and snowfall outlooks for Wednesday.

Tuesday, December 15th 2009 Weather Outlook

Tuesday’s Weather Outlook; Gulf Coast/Southeast System, West System, Great Lakes-Lake Effect Snow

On Tuesday, a system will continue to effect the Southeastern states, while a system continues to push through the West, and lake effect snow continues in the Great Lakes. Showers and storms will be likely in portions of the Gulf Coast and Southeast, as a system continues to push through the region, as another system develops in the Gulf. In the West, rain will be likely in the lowers elevations, along with accumulating snow in the interior areas, Cascades, and Rockies. In the Great Lakes, some lake effect snow will be possible. Some accumulation is likely. Below are the thunderstorm and snowfall outlooks for Tuesday.

Monday, December 14th 2009 Weather Outlook

Monday’s Weather Outlook; Great Lakes/Gulf Coast System, Northwest System

On Monday, a system will push through the Great Lakes, while a system pushes into the Northwest. Snow will be likely along and north of the track of a system pushing through the Great Lakes. Accumulations are likely, with up to 6″ being possible in some areas. Furhter south along the cold front from this system, showers and storms will be likely along the Gulf Coast. A few storms may become severe along the Gulf Coast. Cape values will be around 500 J/KG, LI’s of -3 and Effective Bulk Shear values up to 50KT. Weak forcing and instibility will limit the overall threat. The main threats from any storms that become severe, will be damaging winds and hail. In the Northwest, a new system will push into the region. Rain will be likely in the lower elevations, with accumulating snow being likely in much of the interior, Cascades, and Rockies. Below are the thunderstorm and snowfall outlooks for Monday.

December 13-14th 2009 Plains/Midwest/Great Lakes Winter Storm

Sunday-Monday, Plains/Midwest/Great Lakes Winter Storm

A weak system will eject into the Plains from the West on Sunday. this system will quickly push through the Midwest and Great Lakes by Monday. Precipitation will be confined to the cold side of this system, as moisture will be limited. A swath of accumulating snow will be likely on the north side of the system from South Dakota, eastward through Minnesota, and into Minnesota. A general 1-3″ can be expected in this corridor, with a band of 3-6″ being possible. Below is the snowfall map for this system.

Sunday, December 13th 2009 Weather Outlook

Sunday’s Weather Outlook; Great Lakes/Ohio Valley/Southeast/Mid-Atlantic/Northeast System, West/Plains/Midwest System

On Sunday, a system will push through the Eastern US, while a system quickly exits the West and pushes into the Midwest. Showers and storms will be likely in portions of the Ohio Valley, Southeast, and Mid-Atlantic, associated with a system pushing through the region. A mix of snow/sleet/freezing rain will be likely in portions of the Great Lakes, Northeast, and Appalachians. In the West, a system will quickly exit the region and move into the Midwest. Shoers and storms will be likely over portions of the West , while accumulating snow will be likely in portions of the Sierra, Rockies, Plains, and Midwest. A general 1-5″ will be likely in a swath from the Dakotas into Wisconsin and Michigan. Below are the thunderstorm and snowfall outlooks for Sunday.

Saturday, December 12th 2009 Weather Outlook

Saturday’s Weather Outlook; Mississippi Valley/Great Lakes/Ohio Valley/Southeast System, West System

On Saturday, a system will push through the Mississippi Valley, while a system continues to effect the West. Showers and storms will be likely in portions of the Mississippi Valley, Ohio Valley, Great Lakes, and Southeast, associated with a system pushing through the Mississippi Valley. Further north over portions of the Great Lakes, thermal profiles may be cold enough to support a rain/snow/freezing rain mix. In the West, a system that has been affecting the area will move onshore. Showers and storms will be likely in the lowest elevations, alogn with accumulating snow in portions of the Sierra, Cascades, and Rockies. Below are the  thunderstorm and snowfall outlooks for Saturday.

Wednesday, December 11th 2009 Weather Outlook

Wednesday’s Weather Outlook, Gulf Coast System, Southwest System, Great Lakes – Lake Effect Snow

On Wednesday, lake effect snow will continue in the Great Lakes, while a system continues to effect the Southwest, and a new system develop along the Gulf Coast. Showers and storms will be likely along the Gulf Coast, associated with a new system develop just offshore in the Gulf. In the Great Lakes, lake effect snow will continue in favored areas. Accumulations are likely, with over 6″ being possible in some areas. Due to the large temperature difference between the air and the lake water temperatures, thundersnow may be possible at times, which would increase snowfall rates over 2″ per hour. In the Southwest, a system will continue to effect the area. Showers and storms will be likely, along with accumulating snow in portions of the Sierra and Rockies. Below are the thunderstorm and snowfall outlooks for Friday.