Friday Morning Update

Friday, December 6th 2013, 4:12 am
By: Alan Crone

Posted 3:44am. 

Good morning.  Welcome to the deep freeze.  While we are dealing with sleet and snow this morning across northern OK, this significant arctic air mass will remain in place for several days.  We are projecting sub-freezing temperatures through midday Wednesday.  Far southeastern OK, west Ark, and NE Texas are experiencing a major ice storm.  Damage to the power grid with loss of power is expected across extreme southeastern OK.  The snow and sleet across NE OK will decrease intensity and areal coverage by the mid-morning hours ending between 10am and noon.  Roadways will be considered hazardous in most locations across the state including northeastern OK.   

The 2nd wave of this three wave system is over central and eastern OK at this hour and is producing snow across the I-44 corridor.  Some sleet is still possible near the I-40 area with freezing rain the primary precip mode across far southeastern OK.  Very little snow has occurred across southern Kansas but a few locations have received a dusting.  A short term winter weather advisory has been issued for far southeastern Kansas.  

The short term data suggest this band of snow will continue from southwestern OK into the northeastern part of the state with moderate snowfall southeast of the I-44 corridor.  At this early hour, I'm inclined to lower some of the projections by an inch or so.  This would mean the Tulsa metro from 2 to 5 inches,  locations northwest of Tulsa from 2 to 3 inches, and locations southeast of Tulsa from 3 to 6 inches.  We've already had some reports of 6 inch snowfall across part of NW Arkansas.   Snowfall totals with this system will still be tricky, even at this late hour, due to the temperature and moisture profile.  I'll be tweaking these forecast accumulations through the morning hours with new short term model runs and observational data.

It may take several hours to get accumulation reports from across the region this morning, but radar estimates are in the 3 to 5 inch range along the I-44 corridor at this hour.  We'll try to post some totals on my Facebook pages and also via twitter later this morning.   

The third and final wave of this system will arrive Saturday night into Sunday across the eastern third of the state.  The air mass is expected to be sufficiently cold and deep enough to support all snow.  But the point soundings in most of the data have suggested some drying in the middle portion of the atmosphere.  This profile would support very light precip possibly in the form of light pellets or even drizzle.  If we do see actual snow Saturday night into Sunday morning, it would be very light with no additional significant accumulation possible.   I'm considering lowering this chance from our current 60% to a 40% opportunity.  I won't make this call until after a few more model runs arrive during the morning hours.  

As mentioned above, the temperatures will continue to be extremely cold for a long duration.  Some model data suggest some partial clearing Friday night into Saturday morning.  This is highly suspect but not entirely impossible.  Regardless, the ground cover of sleet and snow will allow temperatures to plummet.  Model data suggestions would place Saturday morning lows in the lower single digits, possible near 2 degrees in the Tulsa metro.  Thankfully wind speeds are expected to remain light.  Daytime highs Saturday would range in the upper teens to lower 20s.   

Sunday morning temps may gradually increase into the lower teens by sunrise with highs in the upper 20s near 30 along with a southwest surface wind in the range of 10 to 15 mph.   

Another surge of cold air is expected to arrive early Monday morning with northwest winds at 10 to 20 mph.  This would keep the highs in the lower 20s and drop the Tuesday morning lows into the lower single digits from 4 to 6 degrees.  We finally anticipate the temps to move above freezing around the Wednesday afternoon period with highs in the mid-30s.   

The official high in Tulsa yesterday was 30 recorded at 2:03am.

The normal daily average high is 52 and the low is 32.

Our daily records include a high of 77 from 1966 and 1939.  The daily record low is 3 from 1950.  

You'll continue to find some information on my Facebook pages and the twitter feed.  

I'll be discussing the forecast on numerous Radio Oklahoma News Network affiliates across the state through the noon hour.  

Thanks for reading the Friday Morning Weather discussion and blog.  

Have a safe day.   

Alan Crone