THE JIG IS UP...

After three outstanding days of late summer weather, the jig is up. An upper level disturbance contained in NW flow aloft has been drifting through the region since Wednesday afternoon. It's triggered showers and a few garden variety thunderstorms which still exist in parts of the area early Thursday. Most spots have measured light precipitation but a few locations, especially in parts of Buchanan, Delaware, and northern Linn County, Iowa have experienced higher amounts approaching 2 inches. Any lingering showers should fizzle or move out by afternoon in all but the far south where some new development could occur late in the day. That should allow for enough breaks in the clouds and a few pops of sunshine to get highs back in the low to mid 80s, warmest in the south where the front will be slowest to depart. Here's what the national blend of models indicates for highs.

Behind the passing front, weak high pressure is back in control keeping skies partly sunny and temperatures mild through Saturday. Highs both days will remain in the upper 70s to low 80s.

The rain machine is likely to start running again late Saturday night, more likely Sunday as a series of mid level disturbances ride the upper level winds out of the Plains. With time a persistent southerly fetch will force deeper moisture into the Midwest. There remains inconsistencies with the forcing tied to key synoptic features and their movement over time. This makes it difficult to pin point the hit and miss showers that will occur from time to time. Confidence is fairly high there will be rain but low on where and how much. Latest trends lend support to the weekend disturbance being somewhat slower and weaker with its rains holding off until Sunday. Once here, they could be around on again off again into Monday (perhaps midweek if the GFS has any clue). Cloud cover will again play a big role in how warm temperatures get. Even with overcast periods the prevailing southerly flow should keep readings Saturday through Monday close to 80. Any breaks for sun could pop some mid 80s south, but heavier clouds and a bit of rain could keep some spots in the mid to upper 70s in the far north. Again, the most likely range is upper 70s to low 80s. Here's what the EURO indicates over the next 10 days. It shows a little spike of warmth Tuesday before a cooling trend sends readings into the 70s later next week.

In the rain department here's what models are suggesting for amounts Saturday night through Wednesday morning of next week.

The EURO

The GFS

The national model blend.

I've had a monster day of business related issues outside of weather so I'm keeping this short and sweet. Until next time, roll weather....TS