AM UPDATE: Major Storm Still On Its Way

Chicago-Dads-Bday-L.A-197-225x300A special thanks to meteorologist Brian Travers for submitting this very detailed discussion of what Iowa can expect in the next 24-72 hours.  We’ll continue to monitor the latest trends in this storm and provide you further updates as they come to us.

As you wake up on Monday morning, you’ll probably hear Snowmageddon, Storm of the Century, Snowpocolypse, Snowtorious B.I.G., Groundhog’s Day Blizzard or the 100 million (people affected) megastorm as ways to describe this weeks upcoming winter storm.  We, here in Iowa should count our blessings even with all the snow heading our way, because our neighbors to our south and southeast will see a crippling ice storm.  So let’s get down to the details.

UntitledAs we have been telling you, this storm bore watching for the past few days and the energy is finally onshore for the past 24 hours, giving us and computer models more to look at and figure out the most likely path.  A building ridge in the west behind a vigorous trough in the central Rockies and Plains will allow for plenty of moisture to stream ahead of a deepening and strengthening area of low pressure on Tuesday. 

So even after we get one to three inches, with more towards northern Iowa on Monday, the main show will still be on hold until Tuesday and early Wednesday.  Right now, the surface low looks to track from Texarkana northeastward towards Cape Girardeau, MO and then towards Huntington, WV by Wednesday.  Look for snow to dwindle early Tuesday from Monday’s departing system, only to ramp up quickly by early afternoon ahead of the low pressure.  Iowa will be on the northern edge of the storm but close enough to get copious amounts of liquid across the area, with the heaviest remaining in the southern 1/4 of the state. 

One thing that we look at are snow to liquid ratios and with this storm, they are going to be quite high.  Normally we will see ratios of 10 or 12 to 1, which means for every inch of liquid we would see 10 or 12 inches, respectively.  However most areas will see ratios near 15 to 1. One exception will be over southeastern Iowa (near Mt. Pleasant/Keokuk) where even higher ratios could be found thanks in part to that area will be in between two upper level jet maxes of 140 kts on Tuesday evening. 

This area is known historically for higher snow ratios, so one can imagine snow ratios nearly 18 or 20 to 1!  So with QPF predictions on the order of 1" or slightly higher, you can do that math and we could see 18-24" isolated amounts from a line from Centreville to Ottumwa to Washington to Muscatine and points southward.  This is where we also the best possibility for thundersnow will be Tuesday afternoon and night.  A TROWAL, or trough of warm air aloft, will also accompany this low pressure as it passes by, and without getting too technical, this will act like elevated thunderstorms do in the summer and bring even higher snows.  We could see hourly rates around two inches per hour.

So how much will everyone get?  This is going to be a big snow total for everyone because of the fact that northern Iowa will be getting more on Monday.  By Wednesday we expect northwestern Iowa to receive 4-8" from a line from Red Oak to Boone to Mason City north and westward.  From Red Oak–Boone-MCW line southeastward (including Waterloo, Dubuque, Cedar Rapids, Quad Cities, Ames, and Des Moines) we expect 8-14" of snow with the 14" closer to Southeast Iowa. 

From Centreville to Ottumwa to Washington and Muscatine southeastward to the IL/MO borders this is where 14-20" will be possible, with locally higher amounts near two feet!  So those are pretty high snow totals but to top that off, we will have to deal with wind. which will produce near blizzard conditions.

The aforementioned area of high pressure in the western U.S. will build in and bring arctic air and strong winds (25-35mph with gusts) on Tuesday night and into Wednesday, even after the snow ends.  Therefore, we will see considerable blowing snow and reduced visibilities near zero in the rural areas and between 1/4 and 1/2 mile in urban areas especially as the snow falls.  Dangerous wind chills in the teens and twenties below zero will also be felt across the state. 

Needless to say, stay indoors if at all possible on Tuesday and Wednesday.  One final tidbit, travel on roads will be nearly impossible and trains and planes will also be affected.  Not only here in Iowa but throughout the middle part of the country.  Flights in/out of Iowa will be affected with MSP, Chicago, KC, Denver, St. Louis, Detroit, Indianapolis, and Milwaukee all being seriously affected by this storm so delays and most likely cancellations will be common.  (oh, and we could talk about the Chicago blizzard for another 8 paragraphs but we will spare you—but if you have family/friends there–the south suburbs are going to get hammered).

A saving grace would be if there were enough thunderstorms in the Dixie states and/or enough convective snow bands in MO and IL to "rob" us of some moisture, but at this time, it seems highly unlikely that this scenario will impact our totals—but it’s something to hope for if you don’t like snow.

So whatever you call this storm, or whatever the national media decides to call it, it will be a doozy.  Please be careful as we welcome in February on a snowy note.  By the way, what happens if the groundhog can’t get out of his hole on Feb. 2nd?  Suffice to say, six more weeks of winter???

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