KEEP THE PARKA HANDY...

A significant storm will bring a white Christmas to the upper Midwest and frigid one for the rest of us. As you can see the Weather Prediction Center shows several inches of snow and winds of 40-50 mph+ which could create near blizzard conditions from NW Iowa through much of Minnesota and NW Wisconsin. The worst of it comes Wednesday and Wednesday night up that way and holiday travelers headed in that direction may want to hold off until Thursday.

Personally, I think the amounts will be substantially more than what WPC shows.. The 0Z EURO shows this for amounts on the Kuchera scale which uses ratios based on thermal profiles colder than the standard 10:1 which will be more accurate in this event. I like a band of 6-12" (potentially more) the catches the area from Minneapolis NW.

The GFS is even more bullish but not so much on the southern fringes , especially in Iowa.

WPC has posted these odds for an inch or more of snow through Wednesday night. The worst conditions look to be near and NW of Minneapolis.

Christmas Eve day a wave forms along the Arctic front bringing snowy blustery conditions further east in the Ohio Valley and Great Lakes. Here's the odds of an inch of snow there the 24th.

For my area snow will be confined to snow showers or flurries as we are situated in a dry slot between the two energy sources NW and SE. Some areas could see a dusting, mainly northwest of a line from Cedar Rapids to Dubuque.

Before the flurries, wind, and cold arrives temperatures Wednesday have a good shot at reaching well into the 40s, perhaps low 50s in the far southeast. The front quickly passes from west to east during the late morning and afternoon. It may generate a few rain showers as the lift interacts with moisture derived from the pre-frontal warm advection. Any that develop will be light and short in duration. The snow showers and flurries would not arrive until Wednesday night as the cold air squeezes out the remaining moisture in the strong cyclonic flow.

As I say, Wednesday morning will be pleasant and many of you may be tempted to leave the house without the heavy coat. That would be a mistake. Look what happens to temperatures in less than 24 hours. They drop as much as 50 degrees in NC Iowa! 35 to 45 degree hits will be common over most of my area. Strong winds will accompany the cold with gusts 30-40 Wednesday night.

Here are the noon temperatures with the Arctic front just approaching my western counties near Cedar Rapids at mid-day. The GFS has mid 50s up to the Quad Cities.

At 8:00AM Christmas Eve morning (18 hours later) we've gone to this.

There will also be a stout NW winds of 30 mph+ all day Thursday meaning wind chills all day will be below zero with wind chill advisories possible, especially in my northern counties where chills will be near or below minus 10 all day. For those attending "safe" gatherings or church services Christmas Eve, these are wind chill projections off the GFS (10-20 below) in most areas. Those values are significant and need to be respected, especially since we haven't had anything like that to get us acclimated so far this winter.

Christmas day will be cold but winds will turn westerly allowing some moderation with highs in the upper teens to low 20s. Better wind chills are expected as well. All in all conditions remain dry Thursday through Saturday with minimal travel impacts aside from the cold temperatures the 24th and 25th.

The next opportunity for any rain or snow would not come until later Sunday or Sunday night. At this point it appears this system will not intercept moisture and necessary forcing for any precipitation until it's right over my area. That should keep the impacts minimal if things don't change over the next couple of days. Plenty of time to see how things evolve. Meantime, don't forget to take that big coat with you when you head out this morning, by evening you'll be glad you have it! Roll weather...TS

THERE'S A WAY TO STILL GIVE DERECHO 911 AS A CHRISTMAS GIFT. HERE'S HOW.

Hi everybody, We have had a tremendous response to our new book Derecho 911, Iowa's Inland Hurricane. We only have 74 copies left from the first printing and we continue to get requests about giving the book as a gift. It's too late to get an actual copy to you for Christmas, but we have come up with a couple solutions that will get the job done until it arrives. All you need to do is order your copy at derechobook.com and we will send you the card and youtube link that will work as the temporary alternative for the book. Here's what you will get.

1. THE FESTIVE CARD OPTION. I have created a special card that announces the recipient is getting a copy of Derecho 911 as a gift. You can print it out, wrap it up, add a bow, and give it as a substitute until the book arrives.

2. THE YOUTUBE PERSONAL GREETING ANNOUNCEMENT. I have also generated a 3:50 minute youtube video message wishing your loved one(s) a merry Christmas with the "personal" announcement they are receiving a copy of Derecho 911. It's a nice intimate touch. Be sure and watch it.

You can give either option or both. Thanks for considering the gift of weather and Carolyn and I are hoping you are enjoying the holiday season as much as we are. All the best...