Ensembles have been indicating robust upper-level blocking should become established for the early part of May, with amplification of the NA pattern in a general trough/ridge/trough configuration as strong H5 ridging develops downstream towards Greenland.


00z EPS 500mb height anomalies @ hour 168:


This evolution may support a deepening storm through the eastern portion of the country into late week and next weekend, as briefly discussed in a previous entry.

Track and details have varied from model-to-model and run-to run with a path through QC and the Maritimes still plausible. There has been some discontinuity as to how consolidated this potential threat may be or if it ejects as a series of flatter waves.

Low clustering from the 00z GFS ensembles, hour 156:


The interpretation from the latest 00z deterministic ECMWF, hour 144:


Hour 168:


Between the short-range threat and this possible next advancing low the general theme continues to be tilted rather wet via the WPC, total precip for days 1-7: