THE DEVIL IS IN THE DETAILS

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NO DEBATE, NO DENIAL...

The big story in the weather the next 7 days is the arrival of warmer temperatures. There is no debate or denial regarding that. Where things have gotten off track a bit is with the amount of warming. For many days the GFS had been adamant about producing highs of 65 to 70 in the period February 17th to the 19th. However, recent runs have come in significantly cooler. In fact, the EURO is now slightly warmer than the GFS.

Here's the old GFS temperature output from Tuesday (specifically for the Quad Cities).

Wednesday, this run has not only eliminated any 70s, it doesn't even have a high in the 60s! It's now 25 degrees colder on the 19th, going from 70 to 45 degrees.

Honestly, even for the GFS that's an abrupt change, and one I did not see coming that fast. However, to my credit, I had concerns about the cold waters of the Great Lakes and the snow cover that surrounds them and said this in my Tuesday night post: "The warmth has a very tough time bucking the cold, dense air at the surface and pretty much stalls over southern Iowa and WC Illinois. I've seen this numerous times in situations such as this. It's a real thing, and models can have a tough time gauging the effect. Hopefully it doesn't force the boundary any further south in future runs. Again, the lack of snow cover up to Wisconsin should help our cause, but it's early February, and things would have to go very right to get highs up to 65 even in my southern counties".

Anyway, the trend is your friend, and models seem to be catching onto my concerns and have come more in line with highs in the upper 50s to near 60 before cooling down on the 19th. I've now resorted to using the National Model Blend (NBM) which reflects my current thinking. The NBM includes the GFS, EURO, High-Resolution Rapid Refresh (HRRR), North American Mesoscale Forecast System (NAM), and Canadian models. It blends them all together to produce an average, similar to ensembles. Here's what it shows.

We could still see some fluctuation down or up in the coming days as model initialization improves closer to the event. In the end, the devil is in the details. I still think the area from I-80 south has a pretty good shot of seeing at least a day with a high of 60. Odds are far lower north of there.

A LATE UPDATE...

It's 2:30am Thursday morning, and the 0Z EURO now carries the warmth into Wednesday the 19th, with it being the warmest day of the entire period, with widespread readings of 64 to 69 degrees. Just when you think you have a handle on things, stuff like this happens. As I said in the paragraph above, fluctuations up or down are still possible. In this case, the up extends the mild weather a day longer, assuming the EURO is right. Here's the new update for highs next Wednesday.

It now appears as if next Wednesday could be the warmest day, with the EURO now showing readings 31 to 35 degrees above normal.

These are the 5-day average temperature departures for noon Saturday through noon next Thursday.

Short term, the warm-up is gradual as a storm passes to the south Saturday. That keeps the warmest air from entering the scene until Sunday and especially Monday. Even so, highs in the range of 45-50 look solid through Friday. 48-53 is on the table Saturday before a nice bounce Sunday gets readings of 55 to 60 from north to south. Then the door is open to the upper 50s and low 60s on Monday and Tuesday if trends hold. Wednesday could be even warmer.

By the way, there is a chance of a sprinkle or very light shower today in the west with the passage of a moisture-starved disturbance. Some mid-level clouds are about all most areas see.

Regarding precipitation chances, there could also be some light rain next Tuesday night or Wednesday when a low pressure passes across northern Iowa. Most of the significant precipitation falls north of the track in the deformation band, with moisture again lacking locally.

If you are seriously wanting precipitation, a time to focus on is February 20-21. Around then a series of disturbances are possible coming out of the mean trough centered over the west. The EURO and GFS are showing the first wave of energy well organized. It also integrates moisture, a huge plus. We may even be close to the snow line as colder air enters the pattern after the 19th.

It's been a while since I've seen a run of the GFS showing this much rain over the 2-week period ending the 27th.

The EURO is less enthusiastic but still shows some amounts exceeding an inch.

With the 500 mb flow shown looking like this going into February 20th, I have to say that's a pattern that is primed for storms, potentially healthy wet ones. Seeing a chart like that gets me very inspired. On paper, it doesn't get any better than that for active weather in the Midwest. The key is whether the trough is as phased as the EURO shows.

With that, I conclude this post with a rousing cheer. Roll weather...TS ON A SERIOUS NOTE, IF I CAN'T MEET MY FINANCIAL GOALS, THIS WILL BE THE LAST YEAR OF THE SITE. IF YOU LIKE THE CONTENT, THE FUTURE IS UP TO YOU. T.S. 75% to my goal.

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