Thursday, October 18, 2012

Taking a look into later October and early November!

Going to take a look at what the forecast model are showing for the latter half of October into early November. We'll start off with the GFS Ensemble mean 2 meter surface temps (or what we would feel in terms of warmth of chill) 
This is from Oct 25- Nov 1st. The GFS (US model) ensembles show more warmth (compared to normal this time of year) over much of the eastern US (excluding the upper Mid West) This is due to ridging building over the central US 
With the ridging over Alaska that would imply more Surface Highs which in time will bring much colder temps into the North tier of the US which is what we see in the GFS ensembles (first image) We also take a look at the European model (which does pretty well in the long range) it too is in agreement with the GFS for the most part. 
While I can't show the surface temp departures like the GFS above, we can get an idea of where the warm weather will be by looking at the next image (850 *5000ft* temps) or low level temps from the Euro model
This as well is inline with the GFS that the latter half of October should be mild for many in the east (though the North East and NW Pac will remain cooler than the central southern US) The Canadian model is a bit warmer than both the GFS and EC in this time frame 
With all this in mind I believe we will see some Indian summer like weather on the way with temps in the central and Southern US (more so southern Plains) with temps around 80 and so 90s possible in parts of TX. Looking even further down the road last day or two of October into first few days into Nov we can see on the GFS and CFS (Climate Forecast system weekly) that cooler air may settle in! 


Also the weekly forecast from the CFS is showing cooler air to move in replacing the warmth
This model (CFS) has done pretty well in the longer range and with ridging starting to show up around Alaska later in the time frame its only a matter of time before much colder air moves into the US! 





Tuesday, October 16, 2012

Large storm to take shape over Mid Western/Eastern US

A large and powerful fall storm is forecast to take shape in the upper Mid West and move slowly east. 
We see the beginnings of this over Montana and into the Dakotas (area of clouds) Jet stream analysis shows the powerful Jet entering the Pacific North West. 
This image shows mean sea level pressure with the main low over Saskatchewan Canada. We look at the short term forecast models for how this system may unfold. Here is what the NAM model shows 24hrs from 2pm October 16 
This powerful Jet streak in the Pac NW is forecast to deepen the Low in southern Canada while sending a cold front plowing east. (also the NAM 48hr forecast)
Though this model puts out rain in the South East, there is some large differences with some other models on just how much if any rain affects North Carolina. Here is what the Official forecast from the HPC 






Wednesday, October 3, 2012

Warm for the rest of the week, turning much cooler by early next week!

Last few days have felt warm and a bit humid (almost late August than early October) while the air will dry in the coming days (though warmth will stay around with temps in the low 80s) By this weekend will a large change in temperatures are forecast. Looking at our forecast model (GFS/ US model) 
Mild temps out ahead of the next front that will really knock temps back.

Both models are valid Monday Oct 8th. All thanks to a large trough setting up over eastern North America.
There are still signs from the longer range more reliable European model as well for cooler temps in the east
Beyond this I expect a warmer/mild pattern as we head into later October with Halloween possibly being mild for the South East? we'll see.