Wednesday, March 04, 2020

March Outlook Analysis

Checking the SOI late last week (February 28th) showed a sharp 25 point rise between February 19-21st. The SOI composites for both a neutral winter and an El Nino winter show weak central US pressure centers. No significant large scale blocks or deep troughs over the next 15-18 days from the composite starting point of February 20th. This should translate to a overall west-to-east movement on storm systems. Most of these will be rain producers for the Ohio Valley.  Any changeover to snow would be brief. These maps are for ~ March 7-10th
The MJO is now in the inner circle. A far cry from the higher magnitude MJO from earlier in the winter especially January. The overall monthly temperature composites show a more transient temperature setup across the central US/Ohio Valley through the middle of March



EPO (Eastern Pacific Oscillation) teleconnection last Friday showed two dips into negative territory.  One around the 7-9th and another less confident dip at mid-month. The first dip coincides with the SOI composites from above.


Today (5 days later) the EURO and GFS ensembles have backed off on the second dip (mid-month). The EURO is more bullish on a colder pattern than the GFS.


The EURO ensembles from last Friday (February 29th) showing the pressure pattern through March 14th. Cold colors represent low pressure.  Warmer colors represent higher pressure. Lines indicate west-to-east winds aloft between March 10 and 14th...This represent fast moving storm systems. See the SOI composites above.
Remember how the today's model EPO output (FIGURE E) for March 18-19 was all over the place? EURO more positive/GFS more negative?  Today's EURO ensemble (Wednesday March 4th) mirrors the west-to-east pattern from last Friday overall. Notice the "buckle" in the central US flow between march 12-14th? That subtle element (also on the GFS--not shown here) is something to watch over the next 4-7 days.

Also Remember the "???" on Figure A above?  The SOI is now showing a sharp 32 point drop

Looking at the SOI composites (17-20 days out from the starting point of Feb 27-29 which puts us at roughly March 17-20th) the answer gets even more murky. The composites couldn't be more opposite. One shows a strong SE ridge/active central storm systems.  The other shows the SE ridge more suppressed with a more active panhandle storm track. 


The northern Pacific pattern has been progressive. No sustainable ridging over the Bering Sea or over Alaska. Fast flow aloft is keeping LOWS barreling east from out of central Asia, over the Pacific and into western North America.

Based on all of this we can conclude the following for the first 3 weeks of March:

* Temperatures should stay near/slightly above normal
* More days in the 50s overall
* Rapid west-to-east flow will keep storm systems moving frequently across the central US 
* Small periods of colder air still possible. Light snow is not off the table.
* Watching the period of March 17-20th