00z Thursday run
GEFS: Mostly Below normal 850mb temp anomalies from thru December 7th (except for 5th). Above normal 850mb temp anomalies December 8th (same) into the 11th (day later). Below Normal 850 temp anomalies 11th thru the 19th (five days longer), then near normal on end of its run on the 20th. Barney peak 13th.
GEPS: Same as GEFS through December 12th. Above normal 850mb temp anomalies December 13th-17th (slightly warmer than previous), below normal anomalies on the 18th and near/above anomalies on the 19th & 20th (end of run). Barney peak 12th.
EPS: Similar to both through December 12th. Then like GEPS above normal 850mb temp anomalies start on the 13th but end on the 16th, a day earlier. Below 850mb temp anomalies on the 17th-19th (end of run), above approaching. Barney peak 12th.
MV site has the MJO in a weakened phase 3 the week starting December 13th. Probably explains the state of flux new found cold next week. This morning's NAEFS 12/13-12/20 is confident of near normal temperatures. NASA & EC progs thru 10 days: Wave 1 amplitude is subsiding, well below normal wave 2 action persists.
This is the bias (alot of bias to correct) GEFS MJO. MJO progression without convection would be a muted contribution. Regardless Tom's outlook of jet extension and a MJO phase 3 makes me skeptical of the GEFS's as cold as the eyes can see week 2 projection.
00z Saturday run
GEFS: Above normal 850mb temp anomalies from December 8th into early on the 11th. Below Normal 850 temp anomalies 11th thru the 13th (six days shorter than on Thursday), above normal anomalies on 14th & 15th, followed by below normal anomalies later on the 15th thru the 19th, above normal anomalies on the 20th & 21st and then below on the last on the 22nd. Barney peak on the 12th.
GEPS: Same as GEFS through December 14th. It s arrival of above normal 850mb temp anomalies is one day later to match the current GEFS. Above normal 850mb temp anomalies through the end of its run thru the 22nd except for the 17th. Barney peak 12th.
EPS: Similar to both through December 12th. Above normal 850mb temp anomalies start on the 13th (same as Thursday) and end on the 16th. Below normal 850mb temp anomalies on the 17th-19th (same), then near normal the 20th and 21st. Raging +EPO at end of its run (yeah I know). Trending weaker with Barney peak 12th.
MV site has a weaker MJO getting to phases 3 & 4. This morning's NAEFS 12/15-12/22 is pretty confident of near normal temperatures. Looks like it follows up/down/up of EPS. NASA & EC progs thru 10 days: Wave 1 amplitude is subsiding, another hit starts day 10, a predicted wave 2 hit starts, strongest since mid November, but at day 10 it rises to near normal. Something to follow during last third of December.
This is the jet extension forecast for the GFS. It is not a surprise the GEFS lost its perpetual cold look and also why wave 1,2 activity is outlooked to increase in the middle of the month.