290
FXUS64 KMRX 090801
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
301 AM EST Sat Nov 9 2024

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(Today and tonight)
Issued at 235 AM EST Sat Nov 9 2024

Key Messages:

1. Warm temperatures again today with increasing clouds ahead of
a slow moving system.

2. Rain chances creep in slowly from the west starting this
evening with better chances overnight.

3. Strong southerly winds expected in the East Tennessee Mountains
overnight with gusts up to 35 mph possible.

Discussion:

In the upper levels, the ridge over the Southeast will remain
in place today. A trough will move into the Mid and Lower
Mississippi Valleys tonight as a closed low spins near MN/IA. At
the surface, high pressure will remain over the East Coast as a
frontal system stalls near West Tennessee with an occluded front
stretching to the vertically stacked low moving from the Great
Plains into the Upper Midwest. Today will be dry with increasing
clouds ahead of this system. Winds will become southeasterly this
afternoon. Highs will be above normal again today in the lower to
mid 70s.

Tonight, rain chances start to increase from the west this evening
with the best chances in the late night/early morning hours.
Thunder is unlikely with low instability present. Strong winds
will be possible in the East Tennessee Mountains and foothills
with a wind direction somewhat favorable for downslope
conditions. The NBM has gusts up to 30 or 35 mph, which seems
reasonable looking at 850mb winds. HREF 850mb winds keeps the low
level jet west of the mountains and shows about 30 knots near the
mountains from a southerly or southwesterly direction. It seems
like gusts of 30 to 35 mph will be the max and a Wind Advisory
will likely not be necessary.

&&

.LONG TERM...
(Sunday through Friday)
Issued at 235 AM EST Sat Nov 9 2024

Key Messages:

1. Best chances for widespread rain Saturday and Sunday

2. Cooling to seasonal normals Thursday and Friday.

Discussion:

Sunday will have the best chances to see widespread precipitation
across the southern Appalachians as the frontal boundary finally
begins to make it`s way through the region. QPF amounts are still
expected to be light with most places likely to stay below 1" of
storm total QPF, with some of the upslope areas having the best
chances to see over 1" of rain over the weekend. Expect most of the
rainfall to come in the form of showers, but right along the front
we could see some weaker thunderstorms develop with the enhanced
lift.

Front will not have a dramatic effect on temperatures for the first
half of the work week with daytime highs still expected to reach the
upper 60`s/70`s for much of the valley through Wednesday as the mid
level ridging quickly builds in and combines with surface winds
eventually turning more southerly and drawing up warmer air.

Heading into Thursday another front is expected to quickly move
through the southern Appalachians. However this front will almost be
an inverse of the previous one. This time expect a more noticeable
change in temperatures, but much lower rainfall from this second
front. We could see some light rainfall along the southern
Appalachian mountains due to orographic lifting, but most places
will see limited QPf for the second frontal passage. However this
second front will bring in cooler air behind it and drop
temperatures 5-10 degrees between Wednesday through Friday.

&&

.AVIATION...
(06Z TAFS)
Issued at 1210 AM EST Sat Nov 9 2024

VFR conditions will prevail this TAF cycle. Light northerly winds
will become southeasterly in the afternoon. Low rain chances will
creep in tonight mainly after this forecast period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             76  59  66  60 /  20  30  70  80
Knoxville McGhee Tyson Airport, TN  74  57  69  60 /  10  40  80  90
Oak Ridge, TN                       73  56  66  58 /  10  50  80  90
Tri Cities Airport, TN              72  51  66  56 /   0  30  80  90

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

$$

SHORT TERM...McD
AVIATION...McD