BIG WEEKEND CRASH...
Monday was the 8th day of April and here in Cedar Rapids (and much of my area), it was another 80 degree day. That makes it 6 of the first 8 days with highs of 80 or above. In only 2 other years have we seen more, 1934 and 1896. This is the most 80s to start May in 59 years. Impressive to say the least.
Below you can see the number of 80 degree highs in each year going back to 1920. Typically we see 8 80 degree days in an average year. With 23 days to go chances are extremely good we'll reach and exceed that level.
The next issue on the table is an active pattern that should bring another heavy rain event to some part of the central Midwest. All the major models set up a front Friday in southern Iowa that will waver around into Saturday night. Energy will ripple along the boundary sparking multiple rounds of showers and storms.
This appears to be another situation where the boundary will be enhanced by the chilly waters of Lake Michigan. North of the front big changes will take place as east winds send sharply colder air into the Midwest. The GFS shows this stark contrast in temperatures at 1:00pm Saturday.
You can see the front stretched across southern Iowa below. Notice the over-running and rain north of the boundary.
Along the boundary moisture is pooled leading to the potential of heavy rain where it occurs. PWATs (precipitable water vapor) leads the charge maxing out at 1.7"
You can see how the GFS's max rainfall lines up north of the front. The eventual position will be critical as to where the heaviest rains end up.
One thing is for sure, if you end up north of the front this weekend (and I think my area will), it's not going to be nice, especially Saturday. Occasional rain, chilly temperatures, and brisk east winds will make for some pretty crummy conditions. A big weekend crash. So sorry! Roll weather...TS