Clouds have hung tough, especially east of I65 through northeast Alabama and into southern-middle Tennessee. Underneath these clouds have been pockets of flurries and a few stronger snow showers. Little change is expected overnight. Periods of clearing are possible, tonight, mainly west of I65. This will help temperatures to chill off. Lows will drop into the low to mid teens all across the Valley. Even a few single digits are possible, especially across Northwest Alabama.
Thursday
Clouds should begin to give way, Thursday, allowing for significant melt off of snow and ice that is still on area roads. It will remain cold, though, as the arctic high settles in to nearly on top of the Valley.
Clouds giving way to a mostly sunny afternoon.
Low: 13 High: 25 (Wind: N 5)
Friday
The next wave of arctic air will begin intruding into the northern Rockies and northern Plains on Friday as another Clipper dives southeastward out of Canada. A broad area of snow will be breaking out across North Dakota with several inches expected. A few snow showers will all remain across the Ohio Valley and Great Lakes but nothing extreme is expected. The Valley will be under the influence of high pressure and that will keep use mostly sunny. As the high settles a bit further to the east, Friday afternoon, winds will turn more southerly and that will allow some warmer temperatures to return to the Valley.
High Cloudiness. Very Cold Morning
Low: 10 High: 36
Saturday
The next arctic front in trail with the above mentioned Clipper will be moving southward through the Midwest on Saturday. By Saturday evening the Clipper itself will be in the eastern Great Lakes and associated with it will be an area of light to moderate snowfall.
Trailing the Clipper with be the front edge of the next surge of Arctic air. By Saturday evening, it wills stretch from Toledo, OH-Bloomington, IN-Marion, IL-Joplin, MO-Dodge City, KS. The heart of the cold will be found in the Upper Midwest and flooding southward through the Plains.
In addition to the Arctic front sinking southward, still watching a piece of upper level energy rounding the base of the trough in Texas and heading eastward into the Gulf of Mexico. It will help to spur rain and rain shower activity across much of the Lone Star State, Saturday.
Clouds Increasing, Warmer
Low: 24 High: 43
Sunday
I am going to continue to follow the Euro (ECMWF) with regards to handling of Arctic front and additional pieces of upper level energy support. The GFS has a historical bias of not being able to handle shallow arctic air well and it appears the 12z run is suffering from this bias and is too slow with the front sliding southward.
On Sunday, the arctic front nears the Tennessee Valley and likely by the evening will be sliding into and possibly through it. At the same time will be see abundant moisture flowing into from the south and southwest as a second piece of upper level energy drops into the base of the trough and merges with the piece moving out of Texas.
This will provide ample support to provide widespread rain to the Valley. Temperatures will be near freezing, Sunday morning, so if precipitation arrives quicker than I expect which would be towards late morning, the precipitation could briefly begin as a period of freezing rain. Temperatures at 5000 feet are forecast to remain near freezing so some sleet could mix in at the onset of precipitation, too.
Some snow is possible further north from I-40 northward into Kentucky.
Arctic fronts can be difficult to forecats and their arrival impacts forecasts greatly. Due to the uncertainties of its speed and exact location confidence in the specifics of the forecast are low.
Rain likely (60%). Precipitation may briefly begin as a period of light freezing rain.
Low: 32 High: 44
Monday
On Monday, yet another Clipper would be diving southeastward out the northern Rockies with yet another surge, likely a stronger one, of arctic air following but it appears like a brief hit is possible with this shot of cold as the pattern will be allowing for strong intrusion of Pacific air to mix in with the Arctic air greatly reducing its impact. The coldest of the air will be confined to the Northern Rockie to the Upper Midest.
For the South a low will likely form along the Gulf Coast. Again, the amount and strength of arctic air that will be across the Mid-Mississippi and Ohio Valleys will play a role in our forecast. If it is stronger is could sink far enough south to be of a concern for the Valley setting up the possibility of a wintry weather scenario.
As of now, I will continue to forecast rain for the Valley but that could change as we get closer to the event and can see just how far south the edge of the arctic air makes it. Further north, widespread light to moderate snow will be accompanying the arriving next Clipper from the Upper Midwest and Northern Plains to the Mid-Mississippi River Valley.
Rain Likely (70%)
Low: 36 High: 46
Tuesday
Waves of Rain
Low: 43 High: 48
Wednesday
Partly Cloudy
Low: 29 High: 43
Thursday
Mostly Cloudy, Rain Showers Possible Late
Low: 29 High:53
Friday
Rain
Low: 38 High: 53
Clouds should begin to give way, Thursday, allowing for significant melt off of snow and ice that is still on area roads. It will remain cold, though, as the arctic high settles in to nearly on top of the Valley.
Clouds giving way to a mostly sunny afternoon.
Low: 13 High: 25 (Wind: N 5)
Friday
The next wave of arctic air will begin intruding into the northern Rockies and northern Plains on Friday as another Clipper dives southeastward out of Canada. A broad area of snow will be breaking out across North Dakota with several inches expected. A few snow showers will all remain across the Ohio Valley and Great Lakes but nothing extreme is expected. The Valley will be under the influence of high pressure and that will keep use mostly sunny. As the high settles a bit further to the east, Friday afternoon, winds will turn more southerly and that will allow some warmer temperatures to return to the Valley.
High Cloudiness. Very Cold Morning
Low: 10 High: 36
Saturday
The next arctic front in trail with the above mentioned Clipper will be moving southward through the Midwest on Saturday. By Saturday evening the Clipper itself will be in the eastern Great Lakes and associated with it will be an area of light to moderate snowfall.
Trailing the Clipper with be the front edge of the next surge of Arctic air. By Saturday evening, it wills stretch from Toledo, OH-Bloomington, IN-Marion, IL-Joplin, MO-Dodge City, KS. The heart of the cold will be found in the Upper Midwest and flooding southward through the Plains.
In addition to the Arctic front sinking southward, still watching a piece of upper level energy rounding the base of the trough in Texas and heading eastward into the Gulf of Mexico. It will help to spur rain and rain shower activity across much of the Lone Star State, Saturday.
Clouds Increasing, Warmer
Low: 24 High: 43
Sunday
I am going to continue to follow the Euro (ECMWF) with regards to handling of Arctic front and additional pieces of upper level energy support. The GFS has a historical bias of not being able to handle shallow arctic air well and it appears the 12z run is suffering from this bias and is too slow with the front sliding southward.
On Sunday, the arctic front nears the Tennessee Valley and likely by the evening will be sliding into and possibly through it. At the same time will be see abundant moisture flowing into from the south and southwest as a second piece of upper level energy drops into the base of the trough and merges with the piece moving out of Texas.
This will provide ample support to provide widespread rain to the Valley. Temperatures will be near freezing, Sunday morning, so if precipitation arrives quicker than I expect which would be towards late morning, the precipitation could briefly begin as a period of freezing rain. Temperatures at 5000 feet are forecast to remain near freezing so some sleet could mix in at the onset of precipitation, too.
Some snow is possible further north from I-40 northward into Kentucky.
Arctic fronts can be difficult to forecats and their arrival impacts forecasts greatly. Due to the uncertainties of its speed and exact location confidence in the specifics of the forecast are low.
Rain likely (60%). Precipitation may briefly begin as a period of light freezing rain.
Low: 32 High: 44
Monday
On Monday, yet another Clipper would be diving southeastward out the northern Rockies with yet another surge, likely a stronger one, of arctic air following but it appears like a brief hit is possible with this shot of cold as the pattern will be allowing for strong intrusion of Pacific air to mix in with the Arctic air greatly reducing its impact. The coldest of the air will be confined to the Northern Rockie to the Upper Midest.
For the South a low will likely form along the Gulf Coast. Again, the amount and strength of arctic air that will be across the Mid-Mississippi and Ohio Valleys will play a role in our forecast. If it is stronger is could sink far enough south to be of a concern for the Valley setting up the possibility of a wintry weather scenario.
As of now, I will continue to forecast rain for the Valley but that could change as we get closer to the event and can see just how far south the edge of the arctic air makes it. Further north, widespread light to moderate snow will be accompanying the arriving next Clipper from the Upper Midwest and Northern Plains to the Mid-Mississippi River Valley.
Rain Likely (70%)
Low: 36 High: 46
Tuesday
Waves of Rain
Low: 43 High: 48
Wednesday
Partly Cloudy
Low: 29 High: 43
Thursday
Mostly Cloudy, Rain Showers Possible Late
Low: 29 High:53
Friday
Rain
Low: 38 High: 53
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