Wednesday, January 07, 2015

It's Here and It's Not Going Away Anytime Soon


As expected, flurries are flying across northern Arkansas and I would not be surprised to see a few into portions of central Arkansas later this morning.  This is not the big weather story, it's the cold.  Temperatures will fall all day long and by late this afternoon, the metro should be in the low to mid 20s with strong northerly winds gusting to around 30mph creating wind chill values in the single digits and teens.  Lows tonight will not reach record values, but will be around 10-14 degrees in Little Rock.  Single digits will be likely north with teens south.  This is just the beginning and I expect around 60 consecutive hours with temperatures at or below freezing.  It's pipe busting cold and I urge you to bring in the pets and check on the elderly.   Like I have been saying, this is NOT historic cold, but it can be dangerous!

Now onto Friday.  In the blog post below, I mentioned the models indicating some light sleet/snow across southern Arkansas.  I didn't buy it whatsoever and now the models have backed off on it and keeps it further south.  With that said, I would not rule out a few flurries, but at this time, no biggie.  I want snow just as much as you do, but I'm not going to wishcast it.

It's really amazing to see the flaw on the extended GFS model.  It has been there ever since I began looking at it (years!), but they never fix it.  I don't even know if they want to fix it.  The last days always trends towards climatology.  It had weekend temperatures, just a few days ago, well into the 40s to near 50 degrees.  Now it shows a high of 29 Saturday and 39 Sunday.  I like the forecast for Saturday, but Sunday's high may come down a few degrees and that's when things get interesting.

Moisture will be increasing Saturday night into Sunday with very cold surface temperatures staying in place.  Several days ago, I posted a forecast temperature profile for Little Rock valid Sunday morning.  It indicated a nose of warm air pushing north a few thousand feet up into the atmosphere.  When I say "warm", I mean a few degrees ABOVE freezing and warm relative to the surface readings at that time.  This would prevent precipitation falling in the form of snow.  It must be around freezing or below all the way up.  As this moisture surges in from the south, I expect a period of sleet and/or freezing rain Sunday morning for many areas.  The models suggest we will warm above freezing and I do agree with that, however, I think the process will be slower than what the models say.  Anything that falls will be light, but just a little can cause problems and the ground temperatures will be very cold.  A transition to plain rain should occur later Sunday.  This is not a major storm system whatsoever, but enough to cause concerns.

I know many of you are saying, "TODD, I WANT SNOW!!!!!!".  Me too!!!!!  With arctic air in place, anything can happen.  There will be more disturbances to watch next week with this cold air in place.  The Euro even indicates something interesting in one week, but the models ALWAYS show something interesting 7-10 days away so I urge caution with that.  I'll keep you updated.

I do see a "January Thaw" arriving around the 17th to 20th as Pacific air should flood portions of the central United States.  How long this lasts is unknown.  I have seen signs of more cold air building in Canada, relative to average, in 15-20 days from now.  We'll see.

It isn't much, but by mid to late morning, maybe a few flurries as the bitterly cold arctic air moves into the state.  
Wind chill values late Wednesday night into Thursday morning could be below zero over northeastern Arkansas with single digits elsewhere.
The GFS brings in some light ice Saturday night into Sunday morning.  It's important to note, the experimental GFS does not.  The Euro brings in precip, but temperatures may be at or just above freezing for all, but northern Arkansas.  Still many uncertainties exist.
The GFS suggest temperatures warm above freezing for plain rain by the afternoon.  IF moisture does come in, I expect the transition process to be slower than model projections. 

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