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Wintry mix to rain to snow Friday

By Ed Hanna, Chief Meteorologist, @weathercafe, edh@wfmz.com
Published On: Feb 06 2013 05:18:43 PM CST
Updated On: Feb 08 2013 12:22:48 PM CST

Look for one to three inches of snow south and west, three to six inches for the central parts of the region, and six to 12 inches of snow to the north and east .

Links:  Hour-by-hour forecasts  |  Interactive radar

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Today: Snow, sleet and rain; becoming all snow late. Coating to 2” by late afternoon (slick spots for some). High: 37

Tonight: Snow, heavy at times; poor travel/blowing snow. Low: 26

Saturday: Clouds/flurries early, then some sunshine and windy (areas of blowing snow). High: 29 Low: 10

The National Weather Service has issued a winter storm warning through Saturday morning.
We are seeing rain and snow this afternoon for most areas (with a bit of sleet mixed in).

There can be a coating to an inch or two by late this afternoon causing slick spots on some area roadways.

The evening commute can be slippery with snow falling at that time in some areas. Snow will come down heavy at times tonight causing poor travel conditions and blowing snow as the wind can gust to 35 mph.

Drivers should check TRAFFIC ALERTS and LIVE TRAFFIC CAMERAS for their commute.

As colder air wraps into this system, all precipitation will change to snow late Friday afternoon and  Friday night.

Look for 1-3” of snow South and West, 3-6” for the central parts of the region, and 6-12” of snow to the North and East .

Clearly, there will be very tight gradients with widely varying amounts (greater amounts north and east; lesser amounts south).

Link:  Hour-by-hour forecasts
Link:  Interactive radar

Drier air will move in for the upcoming weekend, with highs in the upper 30s to around 40 degrees.

Chief Meteorologist Ed Hanna provides more detail:

A significant event is closing in on us, and even at this stage, there are still some uncertainties. Please see our snow totals map which, as the storm evolves, may change. At this point, there are two very distinct and totally separate entities with no connection to each other. The northern and southern branch systems are not “talking to each other “ in any way yet. If, for some reason (30% chance), they never connect, or the connection happens later, we could end up with lower snowfall totals.

On the latest surface map, we see one low pressure system tracking in to the Midwest, the other low down in Georgia. The northern feature is forecast to be near Cleveland on Friday morning, while the southern storm will have tracked to near Cape Hatteras on Friday morning. At this point, it does appear that the southern storm will be the stronger of the two. The "transfer of energy of the northern feature" (weakening/phasing with the southern storm) is key to how all this plays out.

The longer the northern low hangs on without weakening, the flow of air off the Atlantic Ocean will keep the surface temperatures a bit higher.

On the other hand, the faster the transfer happens, the more quickly our winds will be able to swing around into the northeast and north, leading to a colder atmosphere overall. The turn to colder air will eventually lead to greater snowfall totals.

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All that said, we expect a bit of snow and flurries arriving toward daybreak. Snow will likely mix with rain and some sleet during the day Friday. Climatology would suggest that in a “close-call situation” (for surface temperatures), in early February, odds favor all snow. However, with surface temperatures expected to be so close the freezing mark (or slightly above), some of the precipitation may not accumulate (for the first part of the day Friday). However, there certainly could be a few inches developing mainly on non-paved surfaces if the precipitation is all snow.

As colder air wraps in to the storm (when it does), the heaviest precipitation will pick up in intensity after 5 p.m. Friday. The heaviest part of this storm will likely be from 7 p.m. Friday until 4 a.m. Saturday. Winds will increase Friday night and Saturday. Saturday is expected to be a cold day with blowing wind and drifting snow.

Clearly, this is a fluid situation that will be changing as the dynamics change the interaction between these two features solidifies. We warmly invite you to stay tuned to all of our 69 News newscasts and the 69 News AccuWeather Channel for updates.