OUT WITH THE CHILL...

A big late season Canadian high pressure was perched over the area Sunday night resulting in frost on the tulips early Monday. With a light pressure gradient around daybreak, the dense cold air dove into the low lying areas producing some healthy extremes. Illinois City near Muscatine reported a low of 22 with Vinton in the Cedar River Valley plummiting to 23. High elevations were actually warmer with some readings 2-3 degrees above freezing, especially along the Mississippi.

Hopefully, that's the coldest readings we'll see now for the next 6 months. Not a certainty, but a reasonable assumption with the long days and stronger sunshine ahead.

A SIDE BAR

After arriving home from the hospital (where I'm still dealing with the effects of a blood infection and bad heart valve), I was wowed to see the back yard had spots with grass 18 inches high. It was just about to the point where a my old mower wasn't going to get though it. To fight my infection, I have a pump and infusion bag attached to me 24 hours a day. To mow, I knew I was going to have to find a way to rig up a system to haul the contraption around without getting the cords tangled, which sets the thing to beeping and shuts it down. After much experimentation, I found an old gym bag that I could sling over my shoulder that would hold the pump and infusion bag. I cut a couple holes in the bottom of the gym bag for the cords from the pump and infusion bag to freely exit. Then I looped them to my waist where I attached them to a belt and fed them to the picc in my right arm. I was able to mow and get an infusion at the same time. I looked like a moron from back to the future, but I got the job done. After 2 weeks in the hospital you lose a lot of pride!

What got me thinking about the tall grass was all the rain we've racked up the past 3 weeks. After a a bit of a reprieve recently, the pattern looks to have the potential to turn wet again in coming days. How this all evolves is still a bit up in the air, but at least through Sunday I see two systems with the potantial to produce at least moderate rains.

Before they arrive, Tuesday though Thurday looks warmer, with only a light chance of a brief shower or sprinkle along a dying front Tuesday afternoon. Highs should reach into the 74 to 78 degree range all three days putting our recent cool temperatures rapidly to rest

The first chance of more impactuful showers and storms comes Thursday evening into early Friday with the approach of a trough and associated cold front. By then enough CAPE and moisture will be in place for a swath of precipitation. At this point, the severe weather threat appears on the low end with the south most favored for anything with any zip.

Behind the system, readings should cool a few degrees as cyclonic flow aloft develops over SC Canada. That places us close to or just south of the baroclinic boundary Sunday. At that time, guidance is trending towards the development of an upper air low that closes off somewhere over Iowa Sunday and Monday. Vorticity and moisture will be in the increase leading to clouds and occasional periods of rain. Instability looks limited thus thunderstorms appear minimal with precipitation more strataform in nature. This is likely going to lead to plenty of clouds and cooler temperatures much of next week under cyclonic NW flow aloft.

In fact, over the 5 day period, Tuesday April 28th through Sunday the 3rd, temperatures are expected to average 10-15 degrees below normal per day. I could do without that.

Precipitation on the GFS through May 6th continues to be very generous. Including what falls Thursday and again late in the weekend and beyond, the GFS shows this for rainfall the next 15 days.

I guess the take away is to not let your grass get too long and enjoy the next three days which look nice. After that, the pattern turns unsettled once again. Roll weather...TS