JULY GOES OUT LIKE A LAMB...
There's nothing like the extremes of Midwest weather. Take the weekend for example. After a wild day Saturday with extreme heat and strong storms in the north, Sunday saw a complete reversal with a nice cool down and lower humidity. The "ring of fire" set-up just far enough north to dump the extreme rains that were bound to come somewhere in the Midwest confined to SE Minnesota, far NE Iowa, and central Wisconsin. That area picked up 2-5 inch totals.
The storms at my place in Dubuque rocked the house late Saturday evening. Winds reached 67 mph. They knocked out power for 3 hours and took this tree down on a roof just a few houses away from mine.
Now that northwest flow is back in place, the remainder of this week as well as the month of July is going out like a lamb, especially in terms of temperatures. A sharpening trough has the 500mb jet stream looking like this on Thursday.
That results in 5 day temperature departures such as this Tuesday through Saturday. That is special.
As the core of the cool air arrives Tuesday night there is a chance of hit and miss showers and thunderstorms. Guidance is varied on the potential but overall amounts are light and spotty aside from the GFS which looks far too wet. The model blend indicates this for rain Tuesday night.
Ahead of that Tuesday will be a partly sunny day with highs in the upper 70s to low 80s. Pleasant.
Back to that cool air later this week. With the cyclonic flow aloft deepening some minor disturbances will swing SE bringing passing clouds and perhaps some spotty light showers. Moisture looks scant and forcing week so I don't look for widespread coverage and would only anticipate very light amounts (if any at all). Thursday would be the day with the greatest potential (30%).
Thursday also looks to be a very fresh day for July. The model blend depicts highs only in the low to mid 70s.
Highs like that are 5-10 degrees below normal on the GFS. A hint of fall?
So while July goes out like a lamb, there are signs the first week of August turns into a lion with heat again building. We've seen this act before on the GFS where it produces a prolonged period of searing temperatures, with highs over 100. In the end, we never reach the century mark and what heat does develop is usually confined to a couple of days. The GFS is giving it another go and shows unprecedented temperatures beginning August 2nd. The heat is shown rotating around a huge heat dome with a core over 600 decameters centered over Illinois. If something of that magnitude were to develop it would be incredibly dangerous if it lasted for any length of time.
To prove my point, here's what the deterministic GFS shows for highs in the Quad Cities through August 10th.
Out around Des Moines it paints 10 consecutive days of 100 degree heat with 8 consecutive days around 110!
I just want to say, and make it absolutely clear that I don't see such a thing happening. Again, I don't know what is wrong with the GFS thermal parameters but that is out of this world. It would result in an immense natural disaster with significant suffering and loss to humans, animals, and agriculture. I just wanted to share what the GFS shows because it is something I've never witnessed on a model here in the central Midwest during my career spanning nearly 50 years. Crazy!
The EURO does indicate a slow build up of heat and eventually gets Des Moines 1 day of 101 degree heat August 3rd. Far different than the GFS and far more in the realm of reality.
At any rate, we'll keep an eye in trends with the idea much warmer air is likely in early August. Until then, the rest of this week is natural air conditioning. I like the sounds of that. Roll weather...TS