US Final Extended Weather thru May 10

...Pattern Overview And Guidance Preferences...

Medium Range Guidance Maintains Very Good Continuity Through Day 5 With The Differences And Subtle Change Beyond Day 5
Downstream...And Mainly East Of The Rockies (Central And Southern
Plains States).

Much Of The Guidance Separation Results From The Inland Progression Of The Pacific Coast Cutoff. For The Most Part...The Guidance Is Similar As The System Tracks Southwestward Off The California Coast...But The 3/00z Canadian Lags Too Far Behind The Bulk Of The 00z Ecmwf/Gfs/Ukmet Guidance To Consider It In The Mix After 8/00z For Tracking A Progression Of Subtle Wave Energy Downstream Into The Central States.

Across The Southeast And Eventually Up The East Coast...Very Good
Agreement With Track Of The Closed Low. Again...The 3/00z Canadian Is The Outlier...And The Gfs/Gefs Ensembles Are Generally A Tad Faster Than The Ukmet And Ecmwf Guidance. Overall...These 3 Pieces Of Guidance Would Reasonably Handle The Qpf Pattern... Broad Onshore Flow And Thermal Structure Through Day 7.

In Addition...Believe The Medium Range Details Lack Surface
Definition After Day 6 Over The Upper Ohio Valley And New England.
Should Be Good Separation Between The Canadian Frontal Drape And The Coastal System And Its Associated Surface Wave Until The
Boundaries Merge Over The Canadian Maritimes And Labrador Very
Late In The Day 7 Period.

This Times Out Well With The Bulk Of The West Coast System Tracking What Appears To Be A Positive-Tilt Longwave Through Central Canada.

Beyond Day 5...Looks Like The Progression Of The East Coast System Allows For The Western Gulf Of Mexico To Open Up And Release A Low-Level Moisture Stream Into The Ozarks...Mid Ms Valley And Great Lakes.

For The Most Part...The 'New' Surface Graphics Take A Weak Surface Wave Through The Southern Plains (After 8/12z) And Migrate This System Northeastward Into The Great Lakes And St Lawrence Valley By Day 7. This System Allows The Frontal Boundary To Effectively Stall Along The Ohio Valley...And A Secondary Shot Of Slightly Cooler Canadian Air To Follow Behind A Second...And More Active Surface Wave Projected Over Oklahoma On Day 6 (Around 9/12z). This Region Of The Country Was By Far The Bigger Forecast Challenge This Medium Range Period.

...Sensible Weather Highlights...

It Remains Evident That Both Cutoff H5 Circulations Will Play A
Major Roll In Providing The Prevailing Sensible Weather Conditions
Across The Lower 48 This Period.

This Will Be Especially True Across Srn Appalachia...The Piedmont ...Up The Mid Atlantic Coast And Portions Of The Southeast Coastline Of New England As The East Coast Coastal Low Migrates Very Slowly Up The Coast Days 3-7.

Along The West Coast...The Onshore Flow And Unseasonably Wetter
Conditions Along The Higher Terrain Wane After Day 5 As The Bulk
Of The Energy Spreads Into The 4 Corners Region And Settles Out
Downstream Across The Central Plains And Midwest Days 6-7.

With Respect To The Central Plains And Midwest...Anticipate Slightly Cooler Than Normal Conditions North Of The Front As It Sags Gradually Southward Between Days 5-7. Along And Ahead Of The
Front...Active Weather Is Expected With A Series Of Elevated Convective Episodes Moving From The Texas Gulf Coast
North-Northeastward Into The Midwest And Great Lakes.

WTVY-TV 285 N Foster Street Dothan, AL 36303 334-792-3195
Copyright © 2002-2016 - Designed by Gray Digital Media - Powered by Clickability 205999651 -
Gray Television, Inc.