Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS64 KMRX 220733

Area Forecast Discussion
National Weather Service Morristown TN
333 AM EDT Tue Aug 22 2017

.SHORT TERM (Today and Tonight)...A strong upper trough will move
across the Great Lakes with the associated cold front moving
toward the lower Ohio and Tennessee Valleys late today and
tonight. This trough will suppress the upper ridge over the region
southward allowing for increasing southwesterly flow pulling
moisture and instability north. For Today, main forcing will
remain orographic lift thus best chances of convection will be
there this afternoon.

For tonight, frontal boundary will approach the area with
increasing chances of showers and storms area-wide, expecially
over the northern Plateau. Main concern with these storms will be
heavy rain and gusty winds, but model soundings show severe
storms potential is limited.

.LONG TERM (Wednesday through Monday)...An upper level trough is
swinging through the area to start the period. Showers and storms
should be ongoing just ahead of and along the cold front. Best
chances for rain/storms are early then decrease through the day as
the cold front pushes in. As of now it looks like the front exits
sometime Wednesday evening. Once the front passes, cooler and drier
air will rush in bringing a taste of fall-like weather to our area.
Lows on Wednesday night will be in the upper 50s to low 60s, around
5 degrees below normal.

Thursday through Friday look fantastic as we are still cashing in on
the cooler and drier post-frontal airmass. Both days will feature
temps in the upper 70s to low 80s with little cloud cover and lower
dewpoints. Temps at night will be in the upper 50s to low 60s.
Saturday we remain in an overall NW flow pattern but moisture starts
to creep back in from the south, will have slight chance and low-end
chance POPs in place for most areas. Highs still in the low 80s.
Sunday and Monday look interesting as a tropical system across the
state of Texas could end up affecting our weather. Won`t even get
into timing or too many other details this far out but it generally
looks like an upper level trough comes in late in the period,
picking up this tropical system, and transporting it in our
direction. Again, something to watch moving forward.


Chattanooga Airport, TN             93  74  85  66 /  10  40  60  20
Knoxville McGhee Tyson Airport, TN  90  71  82  62 /  10  40  60  20
Oak Ridge, TN                       90  72  82  62 /  20  60  60  10
Tri Cities Airport, TN              89  69  80  59 /  10  40  60  20



$$ is the U.S. government's official web portal to all federal, state and local government web resources and services.