Saturday, January 10, 2015

Slippery Sunday

8:30PM Saturday Update... new model data came in this evening and I examine it for you in this video.  I also have thoughts about the middle of next week and the "January Thaw".  There are already signs that will not last long as winter should come roaring back.


At this point, the only question that remains to be answered is: how long will it take to get temperatures above freezing Sunday?

Most of the data this Saturday morning shows it will finally get above 32 late in the morning towards noon.  It will take longer across the higher elevations of western Arkansas and for portions of north central Arkansas.  Amounts should stay .1'' or less for most of the metro, but where temperatures stay below freezing longer, freezing rain amounts will be a bit higher.  I fully expect winter weather advisories and/or freezing rain advisories to be issued later today for Sunday.

I have little doubt roads will be slippery Sunday morning with improvement by midday.  Of all the days of the week, it's better for this to come in on a Saturday or Sunday when roads are not packed and people are at work/school.  However, many of you will try to get to church in the morning and I urge caution.  Bridges and overpasses will ice up and I expect other road surfaces to as well.  Will there be enough for power outages?  I doubt it at this time.  If there are outages, it will be very minimal based on the current thinking.  If amounts exceed .25'' of freezing rain, then that will become an issue. At this time, the greatest amounts of freezing rain will be around .1'' to .2'' over western and northern Arkansas.  The one thing that can go wrong with the forecast?  If temperatures are slower to recover tomorrow (Sunday).  That's not what we're thinking, but we're going to watch it.  As of Saturday, I really think the main impact will be on travel for a few hours Sunday morning.

This is a meteogram of the GFS from  Read it from left to right and it goes out in time.  The solid red horizontal line is the freezing line.  The pink, jagged line is the forecast temperature.  You can see it's below 32 when the precip starts Sunday morning, then goes above freezing as the heaviest rain moves in.  The rainfall amounts are the blue bars.  Right now, the best forecast is for a change to a cold rain around noon, but we'll watch to see how long it takes temperatures to move above freezing.
The GFS indicates a large area will have freezing rain in the morning, including southern Arkansas.  The highest amounts are west and north.
WPC says it is likely at least .01'' of freezing rain falls Sunday, especially western and northern Arkansas.
The chance for at least .1'' of freezing rain is around 60% over western Arkansas.
The chance for .25'' of ice is almost non-existent.  This is important.  Once you get to .25'', it can be considered an ice storm, but most indications are that this will not happen.


Anonymous said...


Anonymous said...

I do have a question. What happens if the precipitation does come earlier then expected? Will it cause more traveling problems?

NOAA Winter Guidance