Sure, there's a "minor" cooldown coming tomorrow.  
But it's still looking like Sunday could be the significant drop in temperature and possibly our first look at snow in Edmonton.
More on that in a moment.

A couple brief & scattered showers slipped through parts of the Edmonton area early this morning.
As expected, most of the precipitation is east & northeast of the city.
A few more showers are on the way this morning & early this afternoon in east-central & northeast Alberta.
For the Capital Region, it's a cloudy morning and then some sunny breaks this afternoon.
Wind will pick up midday.  Gusts could be in the 40-50km/h range for a couple hours early this afternoon.
Temperatures will once again be in the teens.  Not quite as warm as yesterday's high of 16, but 13 is still above average.

An area of high pressure drops in from the north and brings some cooler air with it tomorrow.
Sunny skies & a high or 9 or 10.

The warm air pushes back in quickly and we're right back to the low to mid teens for Thu/Fri/Sat.

Here's where it gets interesting:
The upper ridge looks like it'll collapse Saturday night/Sunday.  That means colder air aloft will come crashing in.
An area of low pressure will be exitting SE Alberta as a high pressure system crashes in from the NW.
Where those two systems collide, there could be enough lift to produce some precipitation.
The GEM model is currently projecting no precipitation Sunday.
The GFS is calling for upwards of 5cm of snow.

I'm putting it in the forecast as a 60% chance of showers turning to wet snow.
It's WAAAYY too early to talk potential accumulation.  There are a few too many uncertain variables.

However, it's not too early to prepare for cool temps & some precipitation if you're participating in the Halloween Howl run for the Alberta Diabetes Foundation on Sunday
(or any other outdoor activity)

Looking beyond Sunday:
Monday stays chilly, but warmer air bounces back in for Tues/Wed/Thu.
Highs in the 5-10 range (possibly warmer).
Halloween Forecast: Mostly cloudy.  High of 7



Here's the Edmonton forecast:

Today - Mostly cloudy this morning. Sunny breaks this afternoon.
Wind:  W 15km/h this morning.   NW 20-30 gusting to 45km/h early this afternoon.
High:  13

Tonight - Cloudy periods.
Low:  0

Wednesday - Mainly sunny.
High:  9

Thursday - Partly cloudy.
Morning Low:  1
Afternoon High:  14

Friday - Partly cloudy.
Morning Low:  2
Afternoon High:  13

Saturday - Mix of sun & cloud.
Morning Low:  3
Afternoon High:  13

Sunday - Cloudy with a 60% chance of showers turning to wet snow.
Temperature slowly dropping through the day.
Morning:  3
Afternoon:  1