00z April 11th GEFS
Above normal 500mb heights through the 15th. Not so steady outlook given below normal heights were suppose to return in the wake of the South Dakota blizzard tomorrow. Below normal heights on the 15th & 16th (-NAO E / -PNA). Above normal heights on the 17th. Shorter wavelength ridge-trof-ridge +PNA pattern. Below normal 500mb heights arrive with Midwest trof on the 20th thru 23rd when once again the GEFS has that washed out zonal look with near normal heights. +PNA ridge brings below normal heights back on last day of its run on the 26th.
NAEFS for the week of 4/19-4/26 is moderately confident of above normal temperatures, GGEM influenced.
MJO based on Mike's site is in Phase 1, colder phase for us and looks stronger at 200mb than COD. From there the outlook looks weaker. Phases 1-3 are cold in April centered tri-monthly average.
00z April 16th GEFS
Above normal 500mb heights return on the 17th. Another anomalous neg tilt trof brings below normal heights back to the area on the 20th (severe weather before?). This signals the end of the -NAO. Above normal heights return on the 22nd, pretty zonal flow; closed low south of Alaska. CONUS centric ridging then returns near normal heights to our area 25th-28th & as it moves east above normal heights outlooked the 29th thru May 1st (end of run).
NAEFS for the week of 4/24-5/1 is weakly confident of above normal temperatures.
MJO based on Mike's site is in Phase 2, colder phase for us, but also weak. Overall weak COD MJO outlooked to continue.
00z April 20th GEFS
Anomalous closed low eases southeast of us on Monday the 22nd and above normal 500mb heights return into the 25th. +NAO is back. +PNA western ridge returns us to near normal heights & eventually below normal heights with neg tilt trof on the 26th & 27th. Ridge moves eastward & above normal heights return on the 29th. -NAO W/ Neutral PNA & EPO at that point. Developing Rockies ridge brings near normal heights back on May 2nd to end of run on May 5th. -NAO holds, EPO looks trending positive. Wavelemgths are shorter so teleconnections may not be what they used to be in the colder half of the year.
NAEFS for the week of 4/28-5/5 has no confidence in any temperature regime for our area.
MJO based on Mike's site is in a stronger Phase 2, colder phase for us. Outlook is for a re-invigorated MJO to go through phase 3 (also colder for us). There is too much of a GEFS lag to attribute the "unknown" start of May to this.