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Moisture Returns Sunday Through Mid-Week
by Joel Young, Meteorologist/Reporter
January 26, 2013 10:53 PM
These next few days are shaping up to be active after several days of somewhat tranquil weather, at least when it comes to precipitation. Temperatures have been all over the place, especially through the day on Saturday. Even though we do cover a large area, it is still impressive to look at Saturday’s highs and lows across our region. In just 24 hours within our entire coverage area, we’ve seen a large range in temperatures. It’s been as cold as -3 in Sisseton and as warm as 64 in Valentine. That’s nothing unusual or record breaking, but certainly worth noting.   Over the next few days, we shouldn’t see too much variation in temperatures. Increasing clouds Saturday night and Sunday morning will prevent temperatures from dropping quite as dramatically during the overnight. In fact, the clouds are moving in along a warm front which will actually bring slightly warmer temperatures to our region on Sunday.
This system will also bring a chance of rain to our region, and possibly even freezing rain. Because of a deep layer of warm air in the upper levels, also known as a melting layer, snow is pretty much out of the question for most of us on Sunday. However, with surface temperatures dropping below freezing during the overnight hours; freezing rain is possible depending on how early the rain arrives. The following graphics show how two of our most used forecast models disagree on the timing of this rainfall. Notice that the GFS brings the rainfall to our area much earlier than the NAM, which doesn’t bring the rain to our area until a few hours later.   What’s the difference between a few hours? Well, it can make a big difference for those traveling during the morning hours as the rain moves in. If the rain moves in earlier, like the GFS is showing, rain would be more likely to freeze on contact when it reaches the surface. If the NAM solution verifies, we may be able to warm above freezing in the southeast before the rain arrives. As a precaution, several counties in the southeast are under Freezing Rain Advisories through Sunday morning. Even the slightest accumulation of ice on roadways can lead to a big headache when it comes to traveling, so use extreme caution if you’re planning to be out and about.  Winter Weather Advisories are also in effect for parts of Minnesota farther north and east of these counties under Freezing Rain Advisories.
Models do seem to agree a bit more by noon showing most of the rainfall concentrated along and south of I-90 and mainly east of the Missouri River, especially into parts of NW Iowa and SW Minnesota.   By 6 pm, the GFS continues to move this area of rainfall faster than the NAM. Some of this may mix with some light snow showers if the rain tracks much farther north later in the afternoon and early evening. Any lingering moisture after temperatures have dropped back below freezing will also pose a threat on roadways. At this point, the threat for freezing rain should be over by mid-day. Of course, we will continue to monitor the situation throughout the day and let you know if these advisories get extended.   Here’s a look at our Futurecast Rainfall model showing very light amounts, but keep in mind that any ice can cause problems no matter how thin the layer is.  As for the next system, which we expect to move into our area Monday afternoon and early evening; models don’t quite see eye to eye just yet. Of course, once this first system is behind us, they will probably have a much better understanding on how it will set up. Notice the GFS shows quite a bit more moisture associated with a band of snowfall moving across the state around 6 pm Monday while NAM shows almost nothing.   We do expect this to change, though. Especially considering some of our other models, like the Canadian model shown below, are agreeing more with the GFS on how much moisture is associated with this system. Also, since models take current conditions into consideration; the effects of Sunday’s event will likely help models better understand how they will impact Monday’s system.  While we may not know exactly how much moisture we will see from Monday’s system, we do know it will bring much colder air behind it unlike the first. Like they have with these next two systems, our forecast models are flip flopping on how cold we will get toward the second half of the week. Once we see how much rain and snow we wind up with over the next few days, we will be able to answer that question with a lot more confidence since that will play a huge role in air temperature.
Until then, we’ll continue to bring you the very latest on these systems and this week’s upcoming cold snap right here on KDLT and KDLT.com. |
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