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Area forecast discussion 
National Weather Service Jackson Kentucky
618 am EST Thursday Nov 26 2015

issued at 618 am EST Thursday Nov 26 2015

Much like the past several days...quiet weather continues with a
decent spread between valleys and ridges in temperatures this
morning. Forecast has it all covered no changes this


Short term...(today through friday)
issued at 234 am EST Thursday Nov 26 2015

With strong middle/upper level ridging holding over the eastern Continental U.S.
Through Friday...dry and unseasonably warm weather will continue.
Given how well temperatures responded yesterday...opted to
continue to follow the warmer mav guidance numbers for
temperatures today. This will put temperatures into the middle to
upper 60s today. With boundary layer warming even more on
Friday...a few readings around 70 will be possible. This will be a
solid 15 to 20 degrees above normal for highs today and tomorrow.
Lows tonight will again feature a strong ridge to valley spread as
another strong inversion sets up. However...with slightly higher
dewpoints in place...we should remain above freezing tonight with
lows in the middle to upper 30s in the valleys and around 50 on the
ridges. We will likely see some rh's down below 25 percent this
afternoon as we continue to mix down some drier air just off the
surface. Rh's shouldn't be quite as bad on Friday as low level
winds turn more southerly or southwesterly and usher in slightly
better surface moisture. Any rain chances will hold off until at
least Friday night as models continue to trend slower.

Long term...(friday night through wednesday)
issued at 455 am EST Thursday Nov 26 2015

The models are in pretty good agreement aloft through the bulk of
the extended portion of the forecast. They all suppress a
Southeast Ridge through the Holiday weekend as a result of one
area of troughing moving east through the Quebec territory while
another is found over the central rockies. In the resultant...
nearly zonal...flow pattern above our state energy packets of
varying strength will ride past at middle levels from Friday night
through Monday. It appears that the most significant one will pass
by on Sunday night. The western upper low will then move steadily
into the upper Midwest and Great Lakes through middle week bringing
height falls and some weak energy to Kentucky. Just fair model
agreement at the start of the new week breaks down further by
Wednesday with the European model (ecmwf) more aggressive with the southern extent
of the trough when it crosses the Ohio Valley when compared to the
GFS. However...the latest European model (ecmwf) has moved closer to the GFS
solution and is warmer than its 12z version at middle week. This
difference aloft leads to discrepancy in the surface pattern for the
area on Wednesday. With the high level of uncertainty for the middle
week pattern will stick with a general model blend until one of
the possible solutions becomes a clear trend.

Sensible weather will feature a continuation of the mild weather
across east Kentucky through the weekend as the main front will
stay mostly north of the area during this time. Several waves of
low pressure and associated rain showers will pass through the County Warning Area
into Monday. The more significant rainfall totals will likely hold
off until later Saturday into Sunday with a continuation of
soaking showers around into Monday. A cold front may finally push
through the area on Wednesday bringing an end to the rains along
with cooler temperatures...however this forecast remains
uncertain due to differences among the models.

Adjusted the grids from the CR init mainly to slow the arrival of
the better rains until during the day Saturday per the latest
European model (ecmwf) and NAM. Given the relatively high moisture content in place
for the bulk of this forecast...any ridge to valley temperature
distinctions will be rather small.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 618 am EST Thursday Nov 26 2015

VFR conditions and light southeast winds will continue through


Jkl watches/warnings/advisories...


short term...kas
long term...greif

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