Sunday, February 22, 2015

And The Oscar Goes To.... WINTER

10PM Sunday Update... I just read my 2:30PM update from earlier today and the forecast seems to have worked out quite well with the exception for areas south of the metro.  There will still probably be some sleet mixed in as it ends tonight.

School administrators who still have classes scheduled Monday have a tough call to make Monday morning.  There's another wave of moisture which will move across the state late in the morning into the afternoon.  Once again, just like this last system, it will be a quick mover.  The models, even at this stage of the game, differ on details.  The NAM is very enthusiastic with snow while the GFS is ho-hum about it.  The middle of the road approach might be best.  The National Weather Service has gone ahead and continued the winter weather advisory into late Monday to account for this system

As I write this just before 10PM Sunday, the HRRR (which did a fantastic job with today's system) shows the moisture moving into the state late in the morning with the freezing line well south.  This model only goes out 15 hours so we can't see the whole event just yet.  At this time, I think the primary impact will be over western and southwestern Arkansas with decreasing amounts moving to the east.  Once again, this is NOT a major storm. This is what I call a "low confidence" forecast since there are differences in the models.  Here they are from

Remember, this is a computer model and not a forecast.  The GFS shows light accumulations between 6AM and noon Monday across south and southwest Arkansas.

Between noon and 6PM, the system decreases with only light amounts.

The NAM shows a good area of snow and much heavier than the GFS across western and central AR with freezing rain and sleet south.  I have a hard time believing this will verify, but we'll watch it.

Here's my preliminary forecast for Monday.   Please remember, this is low confidence since we do have model disagreement.  With that said, I do believe this system will be a fast mover which would tend to limit amounts.  

2:30 PM Sunday Update....Most of the forecast is on track, but I have a few changes.  I made a point to say this would quickly move through the state and it's going to end up being faster than I thought.   I think most of the precipitation will be gone by midnight to 1AM Monday morning.  This may make it easier for school administrators to make a call.  Next concern are temperatures.  Hi res models keep the 32 degree line north of the metro for quite awhile which may help limit amounts.  We should start as plain rain, go to sleet, then eventually to snow before it ends.  Again, this is NOT a major storm, but one which can cause slick roads.  At this time, I think the highest amounts will be western Arkansas, especially the higher elevations.  Amounts could reach 1-3'' with isolated amounts to 4''.  Across much of the metro, I think we'll have rain to sleet then changing to snow.  Total snow and sleet accumulations will be a dusting to 1''.  I can not rule out isolated higher amounts around and just north and west of the immediate Little Rock area.  South Arkansas will stay rain for awhile, but change to sleet and freezing rain.  Amounts will not be heavy, but could cause slick spots.  Northern Arkansas, you will see very little if anything.  Maybe only a dusting in spots.



Winter wins the Oscar for biggest comeback in a single season.  Ok, joking aside, another round of wintry weather is on the way.  This will last for only a few hours this evening into early Monday morning and we are not talking about huge amounts.  This is advisory criteria which means most amounts will be 3 inches or less.  This video explains how much at your location.

There's still quite a bit of uncertainty as to the precip. type.  I think for much of the metro, we'll have rain, then sleet, then at some point snow.  Western Arkansas should have some sleet, then snow.  Southern Arkansas will have rain changing to freezing rain and sleet.  The snow chances there are not all that great, but there could be a little Monday.  For a change, northern Arkansas will see little if any.

Once again, this video goes into great detail with an explanation of everything.  Hope you enjoy

1 comment:

Anonymous said...

We need a SchoolCon index!!

NOAA Winter Guidance