HUFFING AND PUFFING...
My house is still standing but its a miracle with the big bad wolf huffing, puffing, and blowing with all his might the past few days. Wind gusts of 50mph plus have been common and they have added a real chill to the air, especially at night and during the early morning. Here's some of the gusts reported by the NWS Monday when winds were at peak levels around the region.
Spring is always a windy time of year anyway when large thermal gradients are common. But, it seems to me we've been seeing more high winds than usual. I did some digging and came up with the maximum wind gusts reported at the NWS office in the Quad Cities since April 1st. This is what I found.
Over the 32 day period not a single day had a wind gust less than 19 mph. 21 of the 32 days had at least a 25 mph gust. 19 of 32 days were at least 30 mph. Now the kicker, 11 of the 32 days (34%) had a gust of 40 mph or greater. That's a very windy period!
Going back to the 1st of January, only 2 days (in red) out of 123 had gusts under 10 mph. 79 of the 123 days (64%) had a wind of at least 25 mph. 3 days gusts reached 51 mph. February and April were exceptionally windy months.
I also took at look at April wind gusts and found that in general, on the days with the strongest winds there was a notable trend for a westerly component, especially SW or NW. These occurred during times when strong cold air (or warm air) advection was taking place ahead of or behind departing storms. Nothing unusual about that.
I think it's fair to say we could all use a break from the wind and the rest of the week will be better in that regard. The powerful upper air low over the Great Lakes is starting to break down and progress to the east. That will ease the pressure gradient significantly but there will still be a cool breeze up to 20 mph from the NW (far better then Tuesday's 40-45 mph gusts). The May sun is strong and there will be plenty of it so most areas should reach the low to mid 60s for highs.
Finally, winds turn more southerly Thursday and Friday. Warming commences on schedule. Highs around 70 look good for both days. Friday could be warmer if it weren't for some mid level clouds which pass from time to time. A few spotty late day showers or sprinkles are possible, especially in the south. Little if any rain is currently anticipated. And, if we do get a little more sunshine, readings could approach 75 in spots that get it.
LOW CONFIDENCE WEEKEND WEATHER...
The weekend has some serious uncertainty as the GFS and EURO handle a warm front and its associated precipitation differently. The EURO is far more aggressive with the progression of the warm front and after a dry day Saturday with highs in the low to mid 70s, it breaks out 80 from I-80 south and low to mid 70s to the north. It really goes big Monday with 80-85 areawide.
The GFS is also dry Saturday but keeps highs in the upper 60s to low 70s. Sunday with the warm front stuck well to the south it never gets highs out of the mid 60s north to low 70s south. Compare the GFS below to the EURO above.
Another major difference is that the EURO with the warm front surging north, kicks off some thunderstorms late Saturday night and Sunday morning. This activity departs in the afternoon only to form again Sunday night across the north as the low level jet kicks in. The EURO suggests this for rainfall.
The GFS is so far south with the forcing, warmth, and instability, it keeps everything well to the west showing this for rainfall over the same period.
The key to this puzzle will be how far high pressure builds into the Great Lakes to start the weekend. The GFS plants the high just north of Lake Superior which will put the clamps on the warm front with E/SE winds traveling over the cold waters of Lake Michigan. That's a common occurrence in May holding that warm front closer to the Missouri border. It restricts moisture too keeping rainfall at bay.
Without anything solid to set my hook in, I think a compromise solution is best until a solid trend is established. To me that is highs of 70-75 Saturday. Sunday should be warmer with 70 to 75 north of I-80 and 75 to 80 further south. I do think a chance of showers and storms is justified late Saturday night and parts of Sunday.
Frankly, there is no way to know with great confidence until we see the depth and position of that high later this week. It's a tricky forecast for temperatures and precipitation pin pointing the position of that warm front.
Well one thing is for sure, we are heading for a warm-up of some degree over the next week. That's been well chronicled by the MJO and its progression towards phase 6, a proven warm temperature analog in May. But, around the 14th the MJO is ready to jump into 7, a cool phase in May.
The EPO (eastern Pacific Oscillation) is turning strongly negative, especially on the EURO control. That implies the ridge over the west and the trough building back into the east, similar to what's been going on in recent weeks. The warm-up may only last a week before below normal reading return the 3rd week of May.
So after we get this positive departure early next week with the phase 6 look.
Phase 7 brings us down again to this negative look May 17th. The trough is back over the east. Hmmm, not real thrilled about that but is does look plausible.
Well there you have it. Some good weather for you to enjoy for a couple days. Then we see where trends go for the weekend where confidence for now is in the low end of the spectrum. Roll weather...TS