Let The Storm Begin
by Cody Matz
March 08, 2013 8:14 PM
Its already raining in some areas as this storm gets underway. The low is still developing in eastern Colorado and will hang out in the western Plains for a solid 24 hours before it begins to move eastward Saturday evening and finally start to push the precipitation out of our area. Here’s an update on some of the rain, freezing rain, and snow totals that we are expecting.
The largest impact from this storm still looks like the icing potential for much of the area. Ice Storm Warnings have been issued for the northeast where the greatest potential for significant icing is located. The National Weather Service in Aberdeen highlights the amounts they are expecting in the image below. Our forecast appears to be very similar to the NWS with widespread icing likely. That can be found in the second image below.
A number of issues can be caused by this much freezing rain. Remember that it sticks to everything and the added weight can cause trees and power lines to collapse, and in worse cases, roofs to collapse. Not to mention, driving on ice takes more than a smile so traveling is not recommended tonight or through much of Saturday for some of the hardest hit areas.
The benefit with this storm though, is that the amount of moisture coming with it will aid in making some impressive rainfall totals for this time of year. Below are 3 different pictures for anticipated rainfall. 1 is our in house futurecast model, the second is a second in house model that we have, but just don’t show very often, and third is the storm total liquid precipitation from the Weather Prediction Center.
All three of these paint very similar pictures with the southeast ending up with the most rain anywhere from about two thirds of an inch to just over an inch, with the west receiving far less precipitation.
Now, onto the snowfall potential. This unfortunately, is a very tough forecast. Much like it did Thursday, it looks like 2 different snow bands will set up in our area; one somewhere in the west and the second somewhere in the southeast. These bands are next to impossible to predict where they will land and how long they will stick around because the conditions for these bands of snow don’t develop until just minutes before the first flake shows up on radar giving us no lead time to adjust the forecast if need be. So, you are just gonna have to roll with the punches on this one. But let me at least narrow down the best areas to get these bands. Now, meteorologists often collaborate with each other to get the forecasts as accurate as possible, so we often enlist the help of the National Weather Service and vice versa. Well the NWS produces whats called a “forecast discussion” on a bi-daily basis. Theses discussions spell out what the forecaster is seeing in order to make the current 7-day forecast. Well, I thought the forecaster today said something about these snowbands so well that I just want to use his words…. So here is part of his discussion:
Suspect what will happen on Saturday is the precipitation band in the northern north will fall apart rather than transition from west to east. When the cold front aloft swings into northern Nebraska Saturday afternoon, a new band of precipitation will develop andbecome the dominant feature. This second band will be the one that could produce some heavy snow and its location will be very important.
I thought that was very well stated. So below are a couple of images from computer models showing where they put these two bands of snowfall.
One is crossing our area from the southwest to the northeast and the other one is in the far southeast… mostly northwest Iowa. But compared to Thursday, total accumulation in these bands has seemed to decrease a bit. They now show generally 2 to 6 inches versus 4 to 8.
Here is where our futurecast model puts these two bands…
Pretty similar to what the first two models showed, but I think the band in the southeast is just a bit too wide on Futurecast.
Here is what the WPC thinks. These pictures are the probabilities of getting at least 2 inches and at least 4 inches of snow over the weekend.
They have much of the area with a 50% or greater chance of receiving at least 2 inches of snow. But it does decrease quite a bit for four inches with some isolated spots that have a greater than 50% chance at 4 inches of snow.