Holiday weekend outlook - another Arctic infiltration

The Mid-South has enjoyed pleasant weather for the past couple of days as temperatures have been some 10-15° above normal. A "southern stream" system, meaning that the storm rides along the subtropical jet stream versus the polar jet stream, will affect our weather tomorrow with showers expected starting early Friday morning and ending, for the most part, by lunchtime.

GFS model rainfall forecast from midnight through noon Friday showing light amounts of rain are expected over the metro with heavier amounts well southeast. 

Earlier this week there was a bit of concern over a strong thunderstorm or two. However, it now appears that the best instability will be confined to areas closer to the Gulf Coast and, though a rumble of thunder is possible as the front approaches late morning to early afternoon. Temperatures will remain mild overnight (lower 50s) due to warm southerly wind continuing. We'll rebound to 60° again tomorrow before the front arrives.

Noontime temperatures on Friday as forecast by the GFS model. Relatively warm air cover the Mid-South, but much colder air over the  Midwest is poised to drop south, indicating that the weekend will be much colder.

Behind the front, we cool off substantially, as one would expect in January. Mostly cloudy skies are expected Saturday with temperatures about 20° cooler (lower 40s for highs) as another system moves by well to our south. We had been watching this one with some interest as various computer models had the low pressure center tracking either along the Gulf Coast or further south into the Gulf. The further north, the more likely that some light precip might fall into Arctic air in place over the area.

Southeastern U.S. surface map and forecast precip for Saturday evening from the GFS model. Low pressure will be far enough to our south that we'll see clouds but dry conditions. Note the freezing line in blue over the metro.

It now appears that we will remain dry, with odds of a trace amount of a wintry mix just slightly better than the odds you had of winning the Powerball jackpot lat night. (In other words, Munford could get a foot of snow.)

For Sunday, cold dry air will be in place with lows in the 20s and highs in the 40s. A reinforcing shot of cold air arrives for Monday when some areas may struggle to get above freezing. (Another Monday, another Arctic blast! Happy MLK Day.) The next system to keep an eye on arrives Tuesday/Wednesday with sufficiently cold temperatures overnight and perhaps just enough warmth during the day to warrant monitoring the potential precip type. It is a fairly weak system though, so timing, temperatures, and precip potential are highly uncertain as of this writing. The next best chance for precip after tomorrow will be late next week.

Find the complete MWN Forecast on our mobile apps or here and stay tuned to our social media posts for the latest information.

Erik Proseus
MWN Meteorologist

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