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FXUS64 KMRX 271917

Area Forecast Discussion
National Weather Service Morristown TN
317 PM EDT Thu Apr 27 2017

.SHORT TERM (Tonight and Friday)...
Behind the cold front this evening, we will continue to see
clearing skies from west to east as dry air filters in. The 
combination of dry air aloft, light winds, and recent rainfall 
will result in the potential for patchy fog late tonight and early
Friday morning. Ridging begins to build back in on Friday with a 
southerly flow and temperatures about 10 degrees warmer than 
Thursday. At the surface, a warm front will also move north across
the area with weak isentropic lift leading to some mid-level 
clouds on Friday afternoon.

.LONG TERM (Friday night through Thursday)...
High pressure will maintain control through much of 
the weekend, resulting in a summer- like pattern with very warm 
temperatures. Highs on Saturday will be in the mid to upper 80s, 
potentially breaking some records. For reference, record highs for
Saturday are 88 at TYS and CHA, and 86 for TRI. Despite balmy 
surface dewpoints in the mid 60s, a capping inversion will likely 
suppress most afternoon convection outside the mountains. 
Temperatures will be slightly cooler on Sunday as the high begins 
to lose its grip on the area, but should again be well into the 
80s at most locations. A strong low pressure system will track 
northwest of the forecast area Sunday/Sunday night, bringing a 
chance for some thunderstorms for our area Sunday night into 
Monday as the associated cold front pushes through. Frontal 
passage timing should limit instability and does not appear 
favorable for a large severe threat. However, a marginal wind 
threat appears possible with a low level jet overhead maxing out 
around 65kts.

The frontal passage on Monday will bring temperatures back into the 
70s for the first half of the workweek. Upper level flow becomes 
more zonal as well, with a fast moving weak shortwave bringing a 
brief chance of showers to the far northern part of the forecast 
area on Tuesday night/Wednesday. Another trough will approach the 
area Wednesday into Thursday, bringing the next chance for 
widespread precipitation to the region.


Chattanooga Airport, TN             57  85  66  87 /  10  20  10  10 
Knoxville McGhee Tyson Airport, TN  55  84  65  88 /   0  10  10  10 
Oak Ridge, TN                       55  87  66  88 /   0  10  10  10 
Tri Cities Airport, TN              52  87  59  87 /  20  10  10  20 



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