GETTING OUR MOJO BACK...
We've experienced quite a change in our weather the past couple of days thanks to a realignment in the upper air pattern that scoured out the heat, humidity, and thunderstorms of the weekend. This kinder, gentler brand of summer is looking to be with us now for extended stay. Below you can see the EURO 10-day temperature meteogram shows a modest warm-up over the weekend and then an even bigger change to cooler early fall-like conditions next week.
There is good support for such a trend among models and the MJO (Madden Julien Oscillation). Nothing like that MJO magic to support a long range temperature trend. Note how the MJO (beginning with the red X) is projected to tour phases 2 and 3 the rest of the month.
That is significant when you look at the phase analogs for phases 2 and 3 during August. Temperatures trend cooler than normal. Precipitation is generally light, especially in phase 2 when both the central and upper Midwest correlate to well below normal amounts.
The EURO control shows the cool air beginning to kick in about this time next week. Here's it's temperature anomalies for the period August 17-24th. That fits the phase 2 analogs like a glove.
The EURO precipitation trends are right there too showing little if any rain the next 10 days.
Here are the departures over that period.
The Climate Prediction Center is on board with this thinking showing a similar trend for rain and temperatures in its 8-14 day outlook.
For the first time in at least 2 months CPC shows no risk of excessive heat anywhere east of the Rockies. The heat is finally beat in the overly cooked Plains.
This is intriguing in the sense we are into the last week of August here. We are loosing daylight and heating potential at a good clip and this may break the back of summer. I'm not saying we won't have warm periods late August and early September (we will) but I suspect the worst of this years heat is behind us. Fall is coming folks.
THE HERE AND NOW
Short term only minor changes are expected Wednesday through Thursday with high pressure still in control. Highs both days will generally be in the low to mid 80s which is seasonal. Mostly sunny skies are anticipated.
Thursday night warm advection kicks in ahead of a warm front. The front, the leading edge of more heat and humidity, will make a run towards central Iowa but looks to have a tough time getting out of the southwest half of the state. That keeps us out of the real steam but over time warmer air and higher humidity will gradually be on the increase. That is not the case Friday as clouds and decaying rains to the west could make the day significantly cooler with many locations holding in the 70s. Saturday, and especially Sunday readings warm. Highs Saturday should reach the mid to upper 80s and by Sunday upper 80s to near 90 look attainable.
With the nearly stationary warm front draped from NW Iowa into the SE corner of the state, it will be the focal point for some showers and storms Thursday night and Friday morning. Most of these should avoid all but my far western and southern counties. A few more storms could dot the area Saturday or Sunday but that's highly contingent on the position of the front. Currently, coverage looks limited and the majority of the area may stay dry. Even in those areas that see a shower or storm, they look light and brief and there will be lots of dry hours. Here's what the models are suggesting for rain totals Thursday night through Monday morning.
The NBM (national model blend)
The Weather Prediction Center output
Early next week the upper air flow begins to amplify and retrograde west into the Great Lakes. By the end of the week the EURO shows an impressive trough full of cool air extending from Hudson Bay southward through Chicago.
Look at the below normal temperatures that creates over the eastern 2/3rds of North America. We shall see.
Well, that's enough for now. Be sure and make the most of what promises to be another top notch August day. Roll weather....TS