Area Forecast Discussion
Issued by NWS Springfield, MO

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FXUS63 KSGF 192323

Area Forecast Discussion
National Weather Service Springfield MO
523 PM CST Tue Feb 19 2019

.SHORT TERM...(This evening and Tonight)
Issued at 115 PM CST Tue Feb 19 2019

An upper level trough is currently spreading east into the
southern Plains early this afternoon. The trough will spread
northeast across the Plains tonight and the area on Wednesday.

Ahead of the trough temperatures are currently in the lower to
upper 30s with dew points running 10 to 20 degrees cooler than
current temperatures. Lift will overspread the area this afternoon
from south to north into this evening. The dry air currently in
place across the area will have to be overcome to get
precipitation to the ground. With fairly strong lift spreading
in, the dry air will be able to overcome pretty quickly as the
layer saturates with precipitation falling through it. As the dry
air is overcome, temperatures will cool to the to around 30 to 32
degrees when the precipitation starts.

When the precipitation begins this afternoon it will start off as
all snow or a rain snow mix closer to the MO/AR border. Moderate
to periods of heavy snow will be possible as this band of snow
lifts north across the area into early this evening. The snow will
be fairly short lived, but given the intensity of the snow a
quick 1 to 2" are expected to occur, with locally heavier amounts
possible. The rates should support slushy road conditions for the
afternoon/evening commute. Once the snow rates start to decrease,
its quite possible the snow starts to melt some on roads,
especially farther to the south.

A warm nose will start to spread north into the area this evening
causing the snow to become more rain across south central
Missouri. Some elevated instability will also develop across south
central Missouri allowing a few rumbles of thunder to be
possible. The convective nature could also allow some pockets of
sleet to develop across south central MO this evening.

Farther to the north and west the bigger player on precipitation
type will be the loss of cloud ice as a strong dry slot moves
across the area. Low level moisture will remain high this evening
overnight once cloud ice is lost, and lift will occur within this
low level moisture. This will result in more freezing drizzle or
drizzle occurring later this evening through the overnight hours.
Surface temperatures are going to be really tricky overnight they
should be around the freezing mark, just one degree could be the
difference between freezing drizzle and drizzle. Its possible
temperatures warm overnight or bounce around. With temperatures
near the freezing mark a few slick spots will be possible
overnight, mainly on bridges and overpasses. Generally a glaze to
around a tenth of an inch of ice are expected with locally heavier
amounts up to two tenths possible this evening through the
overnight hours.

.LONG TERM...(Wednesday through Tuesday)
Issued at 315 PM CST Tue Feb 19 2019

As the storm system pushes off to the north and east early
Wednesday morning, the potential for drizzle will remain possible
across central Missouri through about noon. Temperatures for
Wednesday will generally top out in the mid/upper 30s across east
central Kansas to the low/mid 40s across south central Missouri.

Upper level ridging will allow for a warming trend through the
late part of the week with quite weather expected through
Thursday night. The highs Thursday and Friday will top out in
middle 40s to the lower 50s.

The next system to take aim at the Middle Mississippi Valley will
be a deep trough ejecting out across the Central Plains Friday
into Saturday. Models suggest that there will be chances for
showers Friday during the afternoon into the evening, mainly
across south central Missouri along the AR/MO border. However, the
main show looks to take place Saturday.

By Saturday, temperatures will warm into the upper 50s to the
lower 60s across the Ozarks as strong warm air advection is
ushered in by southerly winds. This system will be accompanied by
a strong shortwave that will be ejecting out across the region.
Models suggest the trough becoming negatively tilted with
cyclogenesis taking place across the Texas panhandle region early
Saturday. By Saturday afternoon, a surface low will begin to lift
across western Kansas, tracking to the northeast. As a result,
showers and thunderstorms will increase in coverage across the
region on Saturday. Current models suggest fairly strong synoptic
features to come together. The strongest area of lift will be
focused across the Southern Plains into the Middle Mississippi
Valley. Models show strong divergence aloft over the Ozarks
region, being in the left exit region of both an upper level jet
streak and the a building low level jet. As for the availability
of moisture, a building 50-60 knot LLJ will transport moisture
northward out ahead of the cold front, allowing dewpoints to climb
into the lower 50s across the region with PWAT values of 1.00 to
1.25 inches. Furthermore, model soundings suggest there will be a
significant amount of deep layer shear. On the flip side,
instability continues to be on the marginal side with generally
less than 500 J/Kg of MLCAPE. However, this could be sufficient
enough. Bringing all these ingredients together, there is an
increased likelihood of showers and thunderstorms with this system
Saturday, and there could be a risk for severe thunderstorms. At
this time, the SPC highlights a 15% severe weather Day 5 outlook
generally along and southeast of I-44. This potential threat for
severe weather was also highlighted in the CIPS Experimental
Analog-Based Severe Probability Guidance across southwest Missouri
for Day 5. There will also be a flooding threat with this system
across much of southern Missouri were grounds are already
extremely saturated. In all, will continue to look for model
consistency and trends in the coming days.

Behind this system, temperatures will return to the middle to upper
40s for Sunday with gusty winds behind the exiting system. There
will be a slight warming trend into early next week with highs
topping out in the low 50s Monday and Tuesday. Overall, the
pattern looks to be less active at the early part of next week.


.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 517 PM CST Tue Feb 19 2019

A winter storm was moving across the region this evening
producing impacts to area terminals. Freezing rain, sleet and snow
were producing MVFR to IFR visibilities with MVFR ceilings. Icing
may be a concern for aviators flying into the region with winter
weather expected through 06z with lingering freezing drizzle
expected through 12z Wednesday. Ceilings will fall to IFR after
09z and remain IFR into Wednesday afternoon before slowly
improving to VFR.


MO...Winter Weather Advisory until 6 AM CST Wednesday for MOZ055>058-

KS...Winter Weather Advisory until 6 AM CST Wednesday for KSZ073-097-



LONG TERM...Perez/Wise
AVIATION...Hatch is the U.S. government's official web portal to all federal, state and local government web resources and services.