484
FXUS64 KMRX 130629
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
229 AM EDT Sat Jul 13 2024

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

.SHORT TERM...
(Today and tonight)
Issued at 228 AM EDT Sat Jul 13 2024

Key Messages:

1. A few degrees warmer today. Temps in the low to upper 90s.

2. A few isolated showers and storms possible across the east TN
mountains.


Discussion:

Overall, another hot and mostly dry forecast. A very weak
disturbance will move across central KY today. This slightly raises
the probabilities for a few isolated showers and storms developing
across the area. However, even though the HRRR shows a few spotty
showers across the valley this afternoon, NAM soundings show a
fairly strong mid-level cap in place. Also, NBM doesn`t have any
POPs in for the valley so will go with a dry forecast. The best
chances for any precip are across the east TN mountains, but still
only slight chance POPs.

High temps will be a few degrees warmer today, around 5 to 8 degrees
above normal with temps in the lower to upper 90s. Went well below
NBM guidance for today`s dewpoints based on yesterday`s
observations. Went a few degrees lower than NBM10.

&&

.LONG TERM...
(Sunday through Friday)
Issued at 228 AM EDT Sat Jul 13 2024

Key Messages:

1. Warming trend continues this weekend into early next week, with
the potential for record breaking daily high temperatures for the
start of the work week.

2. Outside of an isolated high elevation shower/storm, mostly dry
conditions are expected through the middle of next week.

3. Chances of precipitation begin to increase by late next week as a
weakness in the ridge develops.

Discussion:

Ridging will remain in control Sunday and into the first half of the
new work week, with mostly dry and anomalously hot conditions. By
Monday and Tuesday, H85 temperatures near 23 to 25 degrees C will
translate to potentially record breaking daily maximum temperatures
across the region. Relative to our previous heat wave, Td will
remain in the mid to upper 60s holding heat indices fairly close in
proximity to the actual temperature - upper 90s to low 100s. While
conditions look borderline at the moment, the area to keep an eye on
for potential heat headlines(such as a heat advisory) would be
central and southern valley. During this time frame subsidence aloft
will restrict isolated diurnal convection to higher elevations.

An upper trough swings into the Great Lakes region mid-week and
flattens out ridging atop the southeast CONUS. A slow moving surface
boundary draping through the Ohio Valley will bring widespread
precipitation chances Wednesday into Thursday alongside a cooling
trend. Better forcing remains displaced well to our north, so while
we may not find ourselves with as much rain as we would like, mean
ensemble guidance suggest that the probability of one-half inch of
QPF through Thursday night is around 70-90%. Furthermore, signals
suggest precipitation chances may linger to some extent Friday into
the weekend as the boundary stalls to our south and upper troughing
becomes stagnant.

Daily Record High Maximum Temperatures

Date    Chattanooga    Knoxville      Tri-Cities     Oak Ridge
07-13   105(1980)      100(1936)      96(1993)       100(1980)
07-14   103(1954)      101(1954)      98(1954)       101(1954)
07-15   103(1977)      98(1995)       96(1995)       100(1980)
07-16   105(1980)      100(1980)      100(1988)      103(1980)
07-17   103(1980)      101(1980)      94(1980)       103(1980)

&&

.AVIATION...
(06Z TAFS)
Issued at 117 AM EDT Sat Jul 13 2024

VFR conditions through the period at all sites with light and VRB
winds.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             98  74  99  75 /  10   0   0   0
Knoxville McGhee Tyson Airport, TN  96  71  97  73 /  10   0  10  10
Oak Ridge, TN                       96  70  96  72 /  10   0  10  10
Tri Cities Airport, TN              92  67  93  68 /  10  10  10  10

&&

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

$$

SHORT TERM...
LONG TERM....KRS
AVIATION...