Coastal Storm Verification (1/25/20 )

As of 22 UTC much of the precipitation has fallen (1.25″ in total) but temperatures are still 52F with a dewpoint of 52F after reaching a high of 53F earlier.

1/25/20 Climatology: Average high: 39F, Average low: 22F
Saturday 1/25/20 Verification: High of 53F and Low of 38F. (+10.5F predicted vs 15F actual); 1″ of rain predicted vs 1.25″ actual.

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The MJO and CONUS Weather

I came across the following plot on Twitter posted by @gensiniwx showing Outgoing Longwave Radiation (OLR) anomalies globally:

Image

This plot indicates weakened convection over the eastern Indian Ocean, Maritime Continent, and parts of the Western Warm Pool (WWP). Alternatively, the Central Pacific Ocean and northeast towards Baja California is an area exhibiting an abnormally large amount of convective activity. This has implications for global weather patterns as it indicates that tropical and perhaps extratropical forcing is having an imprint on the midlatitudes through poleward propagating wave activity. Ths is an amplified phase of the MJO in phase 6/7.

rmm.phase.Last40days.gif

What does this have to do with weather in the northeast? An old rule of thumb dictates that 2 weeks following a strong MJO phase 6, one can expect a drop in the NAO/AO and an increased probability for a strong trough over the eastern United States. If the thermal profiles are right, this phase of the MJO indicates an increased chance of unsettled weather and possibly snow over the eastern part of the US the week of 2/3-2/8.

The problem is, we will have to accomplish this without even a minor perturbation to the stratospheric or tropospheric polar vortex, which is extremely strong and shows no sign of breaking down. If we can get a weak shortwave that takes advantage of a brief period of high-latitude blocking triggered by extratropical wave forcing, that may just be enough. There is some indication of a weakening of the recent persistent +NAO based on ENSM forecasts. A glimmer of hope?

Screenshot from 2020-01-20 23-25-11.png

Coupe