Snowcast Event 6 – Update 3 – Noon, Wed, Jan 27

A major winter storm will begin to impact Oklahoma after daybreak tomorrow – Thursday the 28th.  The most significant change to this forecast is to lower much of the snowfall amounts in the central and southeast.  Emphasis is changing to a freezing rain – serious ice storm – event… with most of the snow limited to the northwest portion of Oklahoma.

The freezing line should be passing the Oklahoma City area during the afternoon tomorrow.  Warm air just above the surface will be allowing precipitation to fall as rain and then freeze on contact with roads, trees and power lines by late in the afternoon.  It may be very difficult to get areas southeast of I-44 to change all the way over to snow.  It is looking more and more likely that the ice associated with this storm may well outdo the snow with regard to headlines.  A rather large swath of the OG&E power grid has the chance to take a hit from this starting in the afternoon and continuing well into the overnight hours.

I have included Okarche in a zone that has a slightly better chance at seeing more sleet and snow than freezing rain.  Hopefully, that’s not a wishcast  – we are just starting to get normal looking trees around here again thanks to the ice events of the past decade.  I expect we will see about a five inch mess of slop that starts with freezing rain and transitions to sleet and eventually snow before ending Friday.

Northwest Oklahoma looks to have the best chance at heavy, accumulating snows.  Eight to 12 inches are not out of the question and there may even be some 18 inch totals before it is over.

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Snowcast Event 6 – Update 2 – Midnight, Wed, Jan 27

This update has only a couple of significant changes involved.  Major winter storm continues on track to cause problems for Oklahoma on Thursday and Friday.  There is not a lot of change in the previous thinking with the exception of two areas:

1) The Panhandle – A quick stop here… overall… it appears that the most significant lifting will be south and east of the Panhandle area.  It still looks as if there will be several inches of snow… but the total amounts expected may be reduced if it continues to look like the main impact will be southeast of this area.

2) And the main difference in the forecast… it is looking more and more likely that there will be a serious – life impacting – freezing rain event develop with this system.  As much as any part of the winter weather type and intensity associated with the storm – this region of significant impact remains hard to forecast 36+ hours out.  GFS/NAM and latest SREF all suggest that a line from Altus to Muskogee would be the most likely areas affected.  The air in the northern Plains and upper Midwest continues to show signs of being colder than expected – much to January normal – and should make a quick surge southward as the storm approaches and surface pressures drop in Texas.  Previously… it was thought that there would be only a couple hour window where freezing rain persisted.  It now appears that portions of the high risk area may see freezing rain fall for six+ hours with accumulations reaching ¾ of an inch or more.  This will likely result in falling trees and power lines… resultant power outages… and the possibility of domino power outages throughout the OG&E system.  Persons living near this area should expect the possibility of extended power outages on the order of many days.  It also makes sense to reduce the total accumulations of snowfall in this region with most of the precipitation expected to fall as freezing rain or sleet.

At this point… there are several signs that point toward a very distinct line which will separate heavy snowfall – from significant accumulations of ice and sleet.  Both are likely to cause extensive trouble for residents and travelers.  In the region of heavy snow – north of I-40… some amounts may exceed 12 inches.  This heavy and wet snow may cause power outages to be as frequent or extended as the ones associated with the freezing rain further south.

Wednesday will be a nice day in Oklahoma.  A perfect one for getting food, prescription meds, generators in order – and any other items arranged that may be needed if you experience extended power outage and travel trouble starting midday Thursday.

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