Cloudy Thur & Fri; Showers Saturday
Good morning folks! The past two mornings have seen quite the temperature inversion with the ridgelines holding to the low - mid 40's above 5000', while the valleys bottomed out to the upper teens - low 20's! This is not unheard of but not common during winter as temperature inversions typically occur during the spring and fall months, as opposed to winter when stronger winds out of the NW are present, hindering cold air drainage/radiational cooling. This is also much more of a spread than we previously forecasted (4 - 8°, compared to 25° seen this morning). Now to the week ahead. Today (Tuesday) we'll see temps run 10 - 12 degrees above normal but cool down to levels 6 - 8 degrees above normal on Wednesday (a change from previous discussion) as high pressure to our northeast influences the region with a weak cold air damming setup. The upper level ridge builds back on Thursday and southerly flow begins to increase at the same time, bringing temps back to levels 10 - 12 degrees above normal for mid December. Sunny skies today and tomorrow give way to increasing clouds Thursday as a weak front approaches the region, but fails to deliver much in the way of rain, minus the TN line. This front was expected to lift north on Friday and initiate light showers across the region but this too looks like a flop, with only mostly cloudy skies overhead and maybe, maybe, a shower or two along the escarpment. A cold front will sweep the region later in the day Saturday and bring us regionwide rainfall with totals this far out forecasted to be anywhere from 0.15 - 0.50" depending upon location; the N GA state line and nearby Snowbird and Unicoi Mountains could see upwards of an inch. Scattered light showers are expected on Sunday, extending into Monday with temps returning to normal levels by early next week.
We'll kick off the timeline Wednesday morning with another inversion across the region as ridgelines above 5000' start the day in the low - mid 40's, while the valleys remain in the upper 20's - low 30's. Sunny skies will only go so far on Wednesday with temps climbing to the upper 40's above 5500', peaking to the low - mid 60's in the valleys, which is roughly 3 - 6 degrees cooler than our previous discussion. Clear skies early in the evening give way to increasing clouds closer to sunrise, capping temps to the upper 30's - mid 40's across the area.
Thursday through Saturday will be warm as temps soar to the upper 60's each afternoon across the lower elevations. Increasing high clouds on Thursday will make it feel a touch cooler than Friday, as Friday brings with it an increase in southerly flow, likely making it the warmest of the three days; cloudy skies remain overhead Friday. Isolated showers are likely Thursday night along the TN line (dry elsewhere), however a chance remains for the escarpment and plateau on Friday due to the increase in southerly flow ahead of the front. The timing of the front is not set in stone but generally we can expect regionwide showers to break out sometime before noon, peaking in coverage during the afternoon hours and fizzling out to isolated coverage later that evening. Overnight lows Thursday and Friday night will be in the upper 40's - mid 50's, dropping to the low - upper 30's Sunday night.
Taking a peak at early next week it seems we keep the cooler weather going, with highs on Sunday only reaching the low 40's - mid 50's (normal for mid December), holding steady or dropping a degree or two as we move into Monday and Tuesday. Light rain chances stick around (yay!) but we will stop here and circle back on Thursday with more details. ENJOY!