Summer 2018 will likely go down as warmest on record for parts of the West, wettest on record for parts of the East while cool in between. The cool Plains was a surprise but the hot West wasn’t.

According to NOAA, June 2018 was the Lower 48’s 3rd warmest June on record.

July was 11th warmest for the Lower 48.

While there was extremes in both lack of rain and excessive rain during June and July, it appears rainfall overall was pretty evenly spread for above and below average.

While July was cool, August has been really cool on the Plains while heavy, flooding rains continued over the Mid Atlantic and parts of the Northeast.

So next lies ahead as we step from summer into fall? With the aid of exceptionally warm water off and against both California and New England, you can bet warmer than normal and where wet, well I recon it stays wet and therefore cool.

Modelling for Europe has shades of 2009 and for the US it too looks similar to 2009 which was warm and wet in the East.

With the onset of a central or modoki El Nino and warm waters off the East Coast, there’s a greater potential for higher humidity, higher temperature (esp at night) and wetter than normal conditions which role right through into early winter.

The CFSv2 has a big positive over southeast Canada which points to an open door for tropical threats underneath. The MJO is also seen to enter a more hurricane conducive phase for the western Atlantic during the 2nd half of September. So, watching the tropics could be the biggest aspect to later September into the first half of October.

Where it’s been cool (Plains), I wouldn’t be surprised if we see an early frost and freeze later September but heat lingers in the West with potential record breaking heat into Southern California with the aid of record warm waters.

Later October, November and even into early December could be very mild and wet up the East Coast.

CFSv2 for September

500mb height anomaly

Precip anomaly

Temp anomaly

October

November

Tags: featured, hurricanes, mjo, monthly-outlook, US fall outlook