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000
FXUS64 KMRX 251330
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
930 AM EDT Thu Apr 25 2024

...New UPDATE...

.UPDATE...
Issued at 929 AM EDT Thu Apr 25 2024

No changes to the forecast for the morning update, and the short
term forecast discussion from this morning is still valid.

&&

.SHORT TERM...
(Today and tonight)
Issued at 332 AM EDT Thu Apr 25 2024

Key Messages:

1. Cool start to the morning, becoming seasonable this afternoon.

2. Increasing clouds late afternoon/evening, with a slight chance of
light rain across southern areas early Friday morning.

Discussion:

High pressure and associated subsidence has lead to mostly clear
skies as noted by surface observations and satellite trends. Strong
radiational cooling has already started to occur, and most places
will fall into the 40s, with a handful of locations potentially
dipping into the upper 30s. Surface dewpoint depressions are highly
varied across the area, ranging from 0 to nearly 10 in some
locations. Very patchy fog still remains a possibility this morning,
otherwise, just a bit chilly for the morning commute.

Upper level heights see minor increases as ridging slowly shifts
eastward atop the region Thursday into Thursday night. Near to
slightly above normal afternoon temperatures are expected as a
result. The light northerly flow and favorable mixing will result in
low afternoon RHs. Given light nature of the winds and recent
rainfall, expect no fire weather concerns. Lastly, cyclogenesis
will take place across central CONUS as a cold front expands from
the midwest into Texas. A warm front and southerly H85 flow across
the southeast CONUS will result in a slight chance of rain
showers early Friday. This is further expanded on in the long term
section below. Overall, a quiet and comfortable near term with
some increasing clouds late Thursday.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 332 AM EDT Thu Apr 25 2024

Key Messages:

1. Low rain chances Friday as a warm front moves through the region.

2. Breezy southwesterly winds Friday through Saturday. Otherwise,
dry and warm conditions forecast over the weekend.

3. A chance of showers and thunderstorms return early next week.

Discussion:

A warm front is still set to lift through the area on Friday.
Isentropic lift will give us slight chance POPs through the day. Any
rain that falls will be light and only a few hundredths of an inch,
which is typical during these types of setups. Models still show the
850mb jet increasing to 30 to 40kts behind the warm front. Winds
across the southern TN valley will become breezy by Friday afternoon
as deep mixing occurs behind the front. Winds will become gusty
across the east TN mountains late Friday afternoon into Friday
night. It still looks like the highest elevations will see low-end
Wind Advisory level winds with gusts from 30 to 40 mph. Though most
locations will see sub advisory level winds. Then, ridging
strengthens across the area over the weekend. Dry on Saturday but
breezy areawide due to deep mixing during the afternoon. Most
locations will see wind gusts up to 20 mph, with isolated gusts up
to 30 mph. Dry and warmer on Sunday with highs 5 to 10 degrees above
normal and plenty of sunshine.

A cold front is still set arrive Monday night into Tuesday and will
give us our next chance of showers and storms. No threat of severe
weather as of now as the low will be across Canada as the cold front
moves through our area. Unsettled weather remains in place through
the end of the long term as we will be in a zonal flow pattern with
high pressure to our south and a broad longwave trough to our north.

&&

.AVIATION...
(12Z TAFS)
Issued at 650 AM EDT Thu Apr 25 2024

Fog should quickly improve at TRI this morning, with VFR
conditions and light winds expected at all sites the remainder of
the TAF cycle. Increasing mid level BKN/OVC clouds and potential
for a light rain shower early Friday morning at CHA. Have opted to
only include VCSH at this time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             78  56  79  63 /   0  20  20   0
Knoxville McGhee Tyson Airport, TN  74  52  75  61 /   0  10  20   0
Oak Ridge, TN                       76  52  75  61 /   0  10  20   0
Tri Cities Airport, TN              70  47  71  55 /   0  10  20  10

&&

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

$$

SHORT TERM...
AVIATION...KRS