Scientific Forecaster Discussion
fxus63 ksgf 150956
Area forecast discussion
National Weather Service Springfield MO
356 am CST sun Dec 15 2019
Short term...(today and Monday tonight)
issued at 335 am CST sun Dec 15 2019
An upper level trough is currently digging south across the
West Coast early this morning. Ahead of this feature shortwave
energy is currently moving across the plains. Starting to see
echos form across eastern Kansas early this morning. There is some
dry air in place so much of these returns will be used to over
come the dry area, but some light snow will be possible early this
Southwest flow aloft is also developing across the region ahead
of the trough. Warm air advection will start spreading into the
area this morning, and strong lift will develop in this warm air
advection. A band of snow will develop across the area, maybe
developing as far south of Highway 60. The warm air advection
will spread north through the day, and the band of snow will also
move north through the day. The northern movement of the band will
slow across the northern portions of the area later this morning
and afternoon, as the warm surge to the north slows as it moves
into the area. Most of the snow today will occur along and north
of the Highway 54 corridor. Given the colder temperatures this
morning, should start to see accumulations pretty quick after the
snow begins, and there could be some decent rates in the middle
of the band. There should be a sharp cut off in snow amounts to
the south. Further south a warm nose and warmer surface
temperatures will spread north and allow more rain/drizzle to
occur. Will have to watch exactly how far north the surface
freezing line makes it as some pockets of freezing drizzle will
be possible at times.
Later this afternoon into this evening the snow band will lift out
of the area and a dry slot will overspread the area. The freezing
line will also start to move back to the south. Significant
moisture will remain in place in the low levels along with plenty
of lift. This will set the stage for a period of drizzle and
freezing drizzle. Will have to watch the southern movement of the
freezing line but generally around or slightly south of Highway 60
and north will see the best potential for freezing drizzle this
evening into the overnight hours.
As the upper level troughs moves east tonight into Monday another
band of snow will develop as cloud ice returns ahead of the
trough. The band of snow will then track across the area through
the day Monday, likely not moving completely out of central
Missouri until later Monday evening. On the southern edge of the
band cloud ice may remain lacking which could still result in more
freezing drizzle along the Highway 60 corridor.
Expect 3 to 6 inches of snow with locally higher amounts to 7
inches possible along and north of the Highway 54 corridor with a
glaze to a tenth of an inch of ice from freezing drizzle possible.
Further south to around Highway 60 a dusting to around an inch of
snow with a glaze to a tenth of an inch of freezing drizzle is
expected. Far southern Missouri will see only minor wintry
weather. Give the increase in snow amounts will upgrade areas
along and north of Fort Scott to Vichy to a Winter Storm Warning
from this morning through Monday evening. South will keep the
Winter Weather Advisory going, did add a couple counties further
to the south to the advisory.
Highs will only warm into the 30s today and Monday afternoon.
Lows tonight will drop into the 20s. Lows Monday night will drop
into the teens to the lower 20s. A snow pack across the north
could result in lows dropping into the middle to even lower teens
Long term...(tuesday through saturday)
issued at 335 am CST sun Dec 15 2019
Colder conditions will remain over the area on Tuesday and Tuesday
night. Then a warming trend will occur into the end of the week as
upper level ridging builds over the region. Another system will
then track through the region late in the week into next week.
Moisture may be lacking which will help limit precipitation
Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1136 PM CST Sat Dec 14 2019
Ksgf/kjln/kbbg tafs: still some IFR ceilings holding on at kbbg
but overall looking at VFR ceilings to start. Lower ceilings and
light precip are expected to spread into the region during the
12z-15z time frame as a sfc wave of low pressure/inverted trough
approach and then move into SW MO/NW Arkansas by late in the period.
Precip might start as wet snow or a wintry mix at ksgf and kjln
before quickly transitioning to rain/drizzle. Expected lowering
ceilings after 12z with IFR common by afternoon/18z. Drizzle is
expected to persist late even after this first wave shifts east.
A transition to freezing drizzle/light freezing rain will be
posisble at kjln and ksgf just after this period.
MO...Winter Weather Advisory until 6 PM CST Monday for moz070-071-
Winter Storm Warning until 6 PM CST Monday for moz055>058-
Kansas...Winter Weather Advisory until 6 PM CST Monday for ksz097-101.
Winter Storm Warning until 6 PM CST Monday for ksz073.