000
FXUS63 KTOP 022126
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
326 PM CST Mon Dec 2 2013

.SHORT TERM...(This Evening through Tuesday)
Issued at 314 PM CST MON DEC 2 2013

Dry and unseasonably warm conditions are still expected through
Tuesday before quickly transitioning over to winter-like
conditions by mid-week. For today, surface high pressure remained
anchored over the eastern U.S. with surface low pressure advancing
into the High Plains as the closed mid- level low progressed
eastward into the Pacific Northwest. This area of low pressure was
very expansive, stretching from the High Plains westward into the
northern Rockies. With this placement of the low, light
southwesterly winds were in place over the region today. Water
vapor imagery showed a stream of mid-level clouds that had
developed in the vicinity of this surface low pressure, with the
clouds stretching over the central Rockies and extending into
central Kansas. Over far east central Kansas, early morning dense
fog lifted by late morning into a stratus deck, which has
continued to linger over the area through the afternoon hours.
Despite the southwesterly winds aiding in waa across much of the
region with afternoon highs reaching into the upper 50s to lower
60s, this stratus deck has limited temperatures to the low/mid 50s
over east central Kansas.

For tonight, the surface low will continue to track southeastward
toward northwest Kansas by Tuesday morning. Light southwest winds
will still be in place over the region tonight, however the wind
speeds may be a couple kts higher than last evening. Additionally,
we can expect to see some scattered mid-level clouds continuing to
stream southeastward into the area throughout the evening hours.
Despite having these conditions in place over much of the area, a
few short-range models are highlighting the potential for some fog
development once again Tuesday morning across extreme eastern
Kansas, where the stratus deck has lingered through the day. The
better conditions look to be in place further east across southwest
and central Missouri, so have just added a mention of patchy fog,
but will continue to monitor these model trends. WAA will continue
through the overnight hours with lows expected to be 10F to 15F
degrees above normal into the upper 30s to lower 40s.

On Tuesday, a mid-level trough will begin to develop through the day
as it digs southward across the western U.S. As this trough
develops, the mid-level low will progress eastward across the
northern Rockies into the Northern Plains. This advancing mid-level
system ultimately will help to shove the surface low southeastward
across the Central Plains through the day. 12z model runs are coming
into much better agreement with the timing of the cold front that
will sweep southward across the region from this passing low. At
this time, the front is progged to start moving into extreme north
central Kansas between 18z and 21z, with the front nearly bisecting
the forecast area from southwest to northeast by 00z With this
timing of the front, should not be seeing winds veering to the
northwest behind the front over north central Kansas until late
afternoon or early evening. As a result, much of the region should
be able to experience decent heating through the afternoon so have
increased temperatures a few degrees over north central Kansas. In
general, the southwesterly winds will aid in another day of waa into
the region and well-above normal temperatures with highs likely
topping out in the mid/upper 50s over north central Kansas to the
low/mid 60s over east central Kansas.

.LONG TERM...(Tuesday Night through Monday)
Issued at 314 PM CST MON DEC 2 2013

Tuesday evening, the strong cold front will push through the
southeast counties of the CWA and move well southeast of the CWA
through the night. There will be little moisture and very weak
ascent, so I`m not expecting any type of post frontal
precipitation Tuesday night into Wednesday.

A broad positive tilt upper level trough across the west central
conus will move east across plains states. All the numerical models
are in agreement with the most intense section of the H5 trough
lifting northeast across the northern plains into the upper Great
Lakes States. Stronger mid-level frontogenesis will develop south of
the CWA from western OK...northeast across northern OK into
southeast KS, then northeast across central MO. This will also
coincide with better moisture and instability for heavier precip
from OK northeast across AR into southern MO. There will probably be
a band of heavier snow developing from northeast OK into southwest
and south central MO. Father southeast across northern AR...eastern
OK and southeast MO there may be heavier mixed precipitation,
including freezing rain Thursday into Friday.

As the positive tilt H5 trough lifts northeast across the eastern
KS, the frontogenetical forcing will increase across the CWA. The
most intense frontogenesis will occur southeast of the CWA, but
areas along and south of interstate 35 may be on the northern edge
of a steady light snow pattern Thursday afternoon and night,
which may result in an inch or two of snowfall. The atmosphere
will be quite dry in the low-levels which may lead to higher
liquid to snow ratios of 17 or 18 to 1. Most areas across the CWA
will probably not record a hundredth of an inch of QPF but there
could be a dusting up to a half inch of snow, due to the high
liquid to snow ratios. Once again the best chances for measurable
snowfall will be across the extreme southeast counties of the CWA
Thursday afternoon into Thursday night.

It will be very cold through the end of the week into early next
week. Afternoon highs on Wednesday will struggle to reach the lower
to mid 30s. Expect even colder Highs Thursday and Friday as the
center of an Arctic surface ridge builds southward across eastern
KS by Saturday morning. Highs Thursday, Friday, and Saturday will
only reach the lower to mid 20s. Some areas along the NE border may
not make it out of the teens for highs. Overnight lows will be in
the teens and single digits. Wind chills will be in the single digit
but winds should diminish Friday night into Saturday as the center
of the surface ridge moves overhead.

Saturday night and Sunday, Another H5 trough will dig southeast from
the Pacific northwest into the four corners region then lift
northeast into the plains. Given the deeper cold arctic airmass in
place across the plains, the stronger ascent ahead of the the next
H5 trough on Sunday will result in periods of light snow through the
day Sunday. The heaviest snow band will develop across north central
KS and lift northeast across eastern NE into IA. There could be a
band of 2 to 4 inches of snowfall along the NE border with most
areas receiving an inch of snow. But this will all depend on the
track and intensity of the H5 trough lifting northeast across the
central plains on Sunday, but limited moisture will preven any
heavy snowfall from developing. The H5 trough will lift northeast into the
upper Midwest Sunday night, so any light snow should end by Sunday
evening. Cloud cover and light snow will only allow Highs to reach
the lower to mid 20s Sunday Afternoon.

Another cold surface ridge of high pressure will build southeast
across eastern KS on Monday. Temperatures will remain in the mid to
upper 20s, despite mostly sunny skies.

The ECMWF shows the rather frigid weather continuing right into mid
December. So far, no major snow storms through the day 10 run of the
model.

&&

.AVIATION...(For the 18Z TAFs through 18Z Tuesday Afternoon)
Issued at 1113 AM CST MON DEC 2 2013

For the 18z TAFs, have VFR conditions through the period with some
mid and high-level clouds over the region through tomorrow. Winds
are expected to remain light out of the southwest. There is a slight
chance for some fog development once again Tuesday morning, however
at this time the best potential looks to stay south and east of the
TAF sites but will continue to monitor for future updates.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Hennecke
LONG TERM...Gargan
AVIATION...Hennecke