Tuesday Morning Update

Tuesday, December 3rd 2013, 4:45 am
By: Alan Crone

We expect one more mild day before cooler air arrives Wednesday and very cold air arrives Thursday lasting through the weekend.  Some wintry precipitation is in the forecast for Thursday and Friday.  Another fast upper disturbance may also bring light snow to the region Saturday evening into Sunday morning.   Our friends from the National Weather service may be issuing Winter Storm Watches for portions of the state before this day is over.  

The first issue is dense fog.  Visibilities will remain very low this morning across a large portion of the state including most locations across eastern OK.  A dense fog advisory will remain for the morning hours.  A few of RAP-RRR runs indicate this fog-low cloud cover may persist through the 10am hour before increasing south winds begin to lower RH values.   

The leading edge of cold air is located across the Rockies and into the central plains this morning and will rapidly move southeast during the day.  Our weather will be mild with afternoon highs in the mid to upper 60s across northern OK and some mid to upper 70s across the southern third of the state into North TX.  The DFW area may hit 78 for an afternoon high.   

The initial wind shift/cold front will arrive pre-dawn Wednesday with north winds and cooler air.  Temps may rebound in the lower 50s by midday and drop into the lower 40s by Wednesday late afternoon with increasing clouds and a few sprinkles across eastern OK and western Arkansas.  The chance for any measurable precip tomorrow remains near or less than 10% for our eastern OK.  

Frigid air will spill into the state Wednesday night and Thursday morning setting the stage for a prolonged period of sub-freezing temperatures that may last for 96 to 120 hours.  We may not move above freezing until late Monday afternoon. 

The upper air flow from the southwest will bring a disturbance over the central and southern OK area by Thursday morning to midday resulting in precipitation developing across part of the state.  The shallow nature of the arctic air may allow for freezing rain and rain across far southern OK, a mixture of freezing rain and sleet across the I-44 corridor, and all snow northwest of the I-44 area for the initial on-set of the precipitation.  The latest data support the higher chances for precip will occur along the I-44 corridor and locations southeast.  The temperature profile by midday will support slightly deeper cold air across the I-44 corridor which would allow for a transition from sleet to some snow by afternoon while southeastern sections may see a transition from freezing rain to sleet.  Friday morning another slug of moisture may move up and over the central and eastern OK area but the temp profile would be deep and cold enough for mainly snow across the northern third of the state and a mixture of sleet and snow to the southeast up through the Arkansas valley of east-central OK.  Model data also supports a small departing upper level wave Saturday night into Sunday morning across the eastern third of the state with the temp profile in the atmosphere supporting all snow.   

The exact amount of accumulating precipitation is problematic due to the varying transitions of precip types during the early stages of the event.  A general idea of 2 to 4 inches of wintry precip seems a possibility along the I-44 corridor through Sunday morning.  Some icing in the form of .10 to .18 of an inch unfortunately is a possibility across the southeastern third of the area, generally south of the I-40 corridor and east of I-35.   

Residents across central and eastern OK should remain aware of the cold air and winter weather potential.  Refinements to the precip type and accumulation amounts will continue to be made as confidence increases in the outcome of the system.  Regardless of the exact amounts, the confidence for travel impacts due to wintry precipitation continues to increase.  If the ice-freezing rain portion of the forecast verifies, some power outages may be a possibility across a narrow area of southeastern or east-central OK.    

The official high in Tulsa yesterday was 59 recorded at 3:09PM.

The normal daily average high is 53 and the low is 32.

Our daily records include a high of 77 from 1916 and a low of 14 from 2006. 

You'll find me on Facebook and Twitter. 

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

Thanks for reading the Tuesday Morning Weather discussion and blog. 

Have a super great day! 

Alan Crone