Short Range Forecast Discussion
Valid 12Z Fri Nov 15 2013 - 12Z Sun Nov 17 2013
...Heavy snows expected along the Cascades and Northern Rockies...
...Showers and thunderstorms will be possible across the Midwest and Upper Great Lakes this weekend...
Active weather is in store for the northwestern corner of the Country
early this weekend as a vigorous piece of energy aloft dives southeast out of Canada. A modest amount of Pacific moisture streaming inland...combined with strong winds against the terrain...should produce moderate to heavy coastal rains and mountain snows across the Northwest...with over a foot of snow expected along the higher elevations of the Cascades and Northern Rockies. The vigorous energy aloft should drop farther southeast Saturday into Sunday...spreading snow showers down into the Central Rockies.
A weak cold front will trigger scattered showers as it crosses the Central Great Basin and Central/Southern Rockies on Friday. Much of the activity will be light in nature...but temperatures should stay low enough to support snow in the higher elevations. The system will quickly race through the Central Plains and Upper Midwest on Saturday...and it should draw up enough Gulf moisture to fuel scattered showers and thunderstorms...especially as it approaches the Great Lakes Saturday evening.
Shortwave energy lifting northeast through the Tennessee Valley and
Mid-Atlantic States could ignite a few scattered showers Friday and
Saturday...but limited moisture in place should keep precipitation totals to a minimum. Farther south...a frontal boundary surging northward in the Gulf of Mexico should bring showers and thunderstorms into Florida for much of the forecast period.
Extended Forecast Discussion
Valid 12z Mon Nov 18 2013 - 12z Fri Nov 22 2013
Relied On The 00z/15 Ensemble Mean From The European Centre As A Synoptic Guide For This Forecast Package. The 00z/15 Ecens Mean Is Well Correlated With The 06z/15 Gefs Mean, With Both Means
Affording A Solid Middle Ground To The Spread Among The Various
After The Passage Of The Very Deep Cyclone Into Southeast Canada Early In The Period, The Pattern Goes Into An Energetic Zonal Mode, With A Serious Uptick In Sensible Weather Threats In The Pacific Northwest.
The Strong, Sprawling Low Pulling Away From The Great Lakes Day 3
Will Be Accompanied By High Winds Over The Lakes Themselves, As
Well As The Elevated Terrain Of The Northern Appalachians With The
Passage Of The Attendant Surface Front.
Thereafter, The Weather Ball Is In The Northwestern Court. A Series Of Vigorous Shortwaves Are Expected To Stream Into The Northern Half Of The United States Pacific Coast--Borne On The New, Stick-Straight, Zonal Southern Stream Striking The Continent.