Wednesday, January 01, 2014

Arctic Air Attack on Arkansas


We have two blasts of brutally cold air in the forecast.  The first arrives tonight with strong northwesterly winds.  It's nothing we haven't already experienced this winter, but it's going to get your attention especially after highs today around 50 degrees.  Wind chill values will drop into the single digits and teens Thursday as well.  There could even be a few areas of light snow Thursday across northern and eastern Arkansas.  I'm not going to rule it out in central areas as well.  This will not be anything significant as the bigger story will be the cold air.  An inch may fall across the north, especially in the higher elevations.


An even bigger blast of cold air will arrive early next week and that one could also arrive with a wintry mix across the northern half of the state.  I know the kids want to extend their Christmas break (parents probably don't).  I may have to bring back the SCHOOL:CON index soon.  Even though some wintry weather is possible, once again the bigger story will be the bitterly cold air.  Highs may not get above freezing for a couple days with wind chill values BELOW zero!  This COULD be the coldest air so far this winter season so consider yourself warned.  Once again, the models underestimate arctic air.  There's always the chance in these situations that it's colder than what the data advertises.  Check out the maps below from weatherbell.com

The Euro snowfall for Thursday morning.  Small amounts possible across the north.

Euro snow for Sunday PM into Monday morning.  A little more significant and some of it could come further south. But the bigger story will be the cold and wind.

This is the GFS valid next Tuesday morning.  See that 1050 mb high in western Kansas?  That's a very strong area of arctic high pressure.  This heavy, dense air will go well into the Gulf of Mexico!!!! Look at those black lines surrounding the high.  Those are isobars (lines of equal barometric pressure).  The atmosphere is TRYING to equalize with air flowing out of the high in a clockwise manner.  The tighter this gradient is, the higher the wind speed.  I think we could have gusts exceed 25 mph. 
With the cold air in place, any wind will drop wind chill readings to extreme levels.  The GFS MIGHT be a little too extreme, but I wanted to share this with you.  By Tuesday morning, it indicates those wind chill values will be around 0 to -15 across the northern half of the state.  That's the green and white color you see.
By Wednesday morning, below zero wind chill values will be possible across much of the state.  Again, this could be overdone a little, but we need to prepare.
In summary, any winter weather can cause problems, even when it's light.  However, the cold will be the bigger story.  The round arriving Thursday is cold.  The round arriving Sunday is BRUTAL.  I'll keep you updated.

1 comment:

jimmylee42 said...

Todd-NWS putting out great stats for weather geeks like us. Looking for that single digit drouth to be broken this winter. We may have had the longest period of time without reaching single digit low temperature in LR since weather records kept? Also looking to see if we have a month this winter where we fail to reach 60 degrees for a high. As you know, a very rare event.

NOAA Winter Guidance