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fxus64 kohx 202233 

Area forecast discussion
National Weather Service Nashville Tennessee
433 PM CST Wed Nov 20 2019

for 00z aviation discussion.



A great fall day today so far with decent ridging aloft ahead of
the plains trough that will be responsible for a wet finish to the
week and start of the weekend. Clouds should be on the increase
tonight, especially north of I-40 as a shortwave trough moves
through the Midwest towards the Great Lakes region. A few short
term models have some light rain as early as the mid morning in
the northwest, but activity may remain isolated/scattered as that
shortwave trough quickly moves to the northeast. Yet another
shortwave is ejected from the larger plains trough Thursday
evening, and pops will ramp up quickly Thursday evening into early
Friday morning for the northern 3/4 of the County Warning Area. Precip will spread
over the entire area Friday morning and continue through the
afternoon. As the trough moves eastward, it will close off over
the Central Plains Friday afternoon and allow for one more good
surge of heavier rain over the far south Friday evening into early
Saturday morning. By mid morning Saturday, the cold front should
be mostly through the area, and precip chances will come to an end
from west to east Saturday late morning through the early evening.
Precipitable water values per model soundings are right around 1.25 inches
during the 24 hour period Friday mid morning through Saturday mid
morning, so expecting a widespread 1 to 2 inches of rain with a
few areas going over 2 inches possible. But with current model
spread most of the area looks to stay within that 1 to 2 inch
range Thursday evening through mid day Saturday.

By Sunday, the trough will be just off to the east, with cooler
air behind the front settling in. Cloud cover will still be
hanging around, especially in the east, and 850 mb temps will be
below 0c Sunday morning. Didnt add mention of sprinkles or
flurries, but model soundings do show a shallow saturated layer in
the low levels which may allow for some light precip Sunday
morning in the east. Otherwise expecting dry conditions to return
Sunday and Monday. Next shot at precip looks to come in on Tuesday
with yet another plains trough moving eastward. The European model (ecmwf) is most
aggressive with quantitative precipitation forecast while the GFS has a much stronger upper low
with quantitative precipitation forecast holding back about 12 hours compared to the European model (ecmwf). Both
models however have a strong cold front move through as the upper
low travels north of the mid state through the Midwest. It looks
like the coldest air stays north, so hopefully we avoid any frozen
precip issues with Holiday travel next Wednesday. Both models have
precip out of the area by Wednesday afternoon, but are quick to
develop additional chances at rain Thanksgiving day. After this
point, solutions diverge quite a bit but hint at the active
pattern holding through next weekend after the Holiday.


00z taf discussion.

Bna/mqy/ckv/csv...a surface ridge will slide off to the east
overnight, paving the way for the next cold front that will begin
affecting middle Tennessee maybe tomorrow afternoon and
definitely by tomorrow night. In the near term, look for VFR
conditions, with winds increasing from the south-southwest tomorrow, and
perhaps a shower or two affecting ckv after 18z.


Ohx watches/warnings/advisories...


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