Sunday, December 09, 2012

Monday Morning Surprise?


You just gotta love Arkansas Weather.  You know my saying, "Never Say Never To Arkansas Weather".  It's probably one of the reasons why I grew up wanting to be a meteorologist.  Our weather can change so drastically in such a short time!  Today we had severe thunderstorms and possible tornadoes and Monday, it's not out of the question for a few snowflakes!  However, the chance is still small.

The NAM is at it again.  Remember, this was the only model out there that had snowfall in the forecast Monday morning.  However, the past few runs dismissed the chance.  Now, it's showing some flakes once again with sleet as well.  However, I still believe this will not amount to much if anything due to several factors.  The first is the warm ground from the recent mild weather.  Second, surface temperatures should be above freezing in central Arkansas and in the mid and upper 30s.  However, I can see a situation for areas north and west of Little Rock in the higher elevations where a little accumulation happens on grassy surfaces....IF THE NAM WERE RIGHT!  Remember, that's assuming this model has the right idea.  Regardless, it won't last long and it will be light.

An area of low pressure aloft will move into Arkansas from the west.  At the same time, there will be some moisture across the area so that some of it could be squeezed out of the air in the form of flurries or sleet pellets.  The best chance for this is across the northwestern half of the state from near Mena to near Little Rock up into far northeastern Arkansas.  Everywhere north and west of that line, has at least a small chance Monday morning.

Here's the NAM displayed using BUFKIT (a weather program).  This shows us what will happen starting now all the way out to 84 hours.  You MUST read this backwards, from right to left.  The green bars are rain, the orange is sleet, and the blue snow.  Notice Monday morning there's at least a few hours where Little Rock could see light sleet and/or very light snow/flurries.  Due to the conditions outlined above, IF this happens, there won't be any problems.  The red wavy line is the surface temperature.  Notice how it crashes tonight as the cold air comes in and stays low while this model shows it precipitating.  Then the temperature rebounds during the afternoon into the mid 40s.  I'll keep you updated.

This is the 00Z NAM showing snowfall accumulations.  This is in line with what I was talking about above.  NW of Little Rock in those higher elevations could see a little dusting.  Again, IF this model actually is right!.  What should you take from this?  The areas in pink and purple have the best chance for seeing a few flakes and sleet pellets.  No need to panic.  We'll see if it's right in the morning.

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