THE OLD FLIP FLOP....ARGH!
For about a week both the GFS and the EURO were bullish on digging a deep trough into the Midwest about October 11th. The end result was to be the first real punch of cold air that would bring widespread frost and even freezing temperatures. As recently as yesterday the EURO was sill adamantly showing such a development.
Today, no such thing as both models have split the trough and the lack of phasing cuts the cold off keeping it safely to the north near the Canadian border. I must say after a week of consistency that was a big shock, I sure didn't see it coming. Let me show you the comparison of yesterday's EURO to today's.
Here's the cold 500 mb trough yesterday.
Here's the split that popped up today. What a radical change.
The associated temperature anomaly at 5,000 feet yesterday. Very chilly stuff with highs barely above 50.
The temperature departure today. Yowza!
Now the surface pattern yesterday. You can see a big 1036mb Canadian high capable of producing plenty of frost and freezing temperatures.
Today nothing like that exists. Bye bye cold.
It's pretty rare that the EURO flips after so much consistency but alas, it did it to me this time. Bottom line we'll have to wait a bit for the first cold shot of the season. I'm a little bummed about this but I'm sure there's far more of you who consider this a positive development. Here's to you!
By the way, the EURO is also showing the MJO (Madden Julian Oscillation) heading into phase 4. That phase in October is noted to produce cooler than normal weather. You can see the MJO cycling by following the dotted green lines through the 8 phases below. You can also see off to the right the cool air that covers the NC United States in phase 4.
Interestingly enough the EURO operational model are not showing any cool air. Here's what it has for temperature departures day 5-10. (Oct 10-15th)
What this tells me is either the EURO's MJO forecast is wrong or this run of the operational model has not caught on to it's own MJO tendencies. Something is fishy!
Whatever the case the case we are now set up for what should be a healthy rain event to kick off the weekend. Here's what the hi-res 3k NAM is showing for rainfall.
The 0Z GFS has this for total rain.