Area Forecast Discussion
Issued by NWS Topeka, KS
FXUS63 KTOP 030528
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
1128 PM CST Mon Mar 2 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 339 PM CST MON MAR 2 2015
Water vapor imagery showed a broad mid-level ridge in place across
the central U.S. with a mid-level trough continuing to deepen west
of the Rockies. As a result, southwesterly flow aloft was helping to
advect a steady stream of moisture into the region, resulting in
mid/high clouds blanketing the area today. At the surface, high
pressure was gradually shifting to the east with an area of low
pressure focused over the Rockies. Winds this afternoon increased
out of the southeast, however the overcast skies still kept
temperatures below normal in the upper 30s/near 40 degrees.
Regional radar this afternoon showed some scattered light
reflectivity returns as model soundings depicted some increased
saturation in the low levels. However, there appears to still be too
much dry air for any of this light precipitation to actually be
reaching the ground, but perhaps there are a few scattered sprinkles.
Soundings show this saturation in the low-levels increasing into
this evening with some isentropic lift present. The main trend with
the models for tonight into Tuesday is that there seems to be more
mid-level dry air being advected into the area ahead of the
approaching cold front. As a result, have lowered PoPs during this
period to slight or low-end chance PoPs and instead expanded the
mention of drizzle. As the low pressure system advances into
western and central Kansas tonight, winds will veer to the southwest
and increase in speed overnight, resulting in warm air advection
into Tuesday morning. As a result, the low temperatures should occur
during the mid-evening hours tonight with rising temperatures
overnight. Have temperatures briefly dropping into the low/mid 30s
before warming into the mid/upper 30s. As a result, have a mention
of rain, freezing rain, or freezing drizzle for portions of far
northern and far northeast Kansas initially this evening before
warming enough for it to transition to rain/drizzle. Due to the
limited amount of available moisture, do not anticipate any ice
accumulation from any light freezing rain/drizzle that develops.
Better chances for light rain overnight through Tuesday morning look
to be focused east of a line stretching from Council Grove to
Manhattan to Marysville. The cold front is expected to track
eastward across the forecast area Tuesday morning through early
afternoon with dry air moving in behind it. As a result, expect any
precipitation to end from west to east with dry conditions likely by
the afternoon. Breezy southwesterly winds will shift to the
northwest, supporting decent cold air advection during the afternoon
hours. As a result, have a non-diurnal temperature trend for Tuesday
as temperatures should fall through the afternoon. With the timing
of the front, expect a decent temperature gradient to develop over
the area, with highs likely ranging from the low 40s northwest to
the upper 40s southeast.
.LONG TERM...(Tuesday Night through Monday)
Issued at 339 PM CST MON MAR 2 2015
Tuesday Night and Wednesday, a positive tilt upper level trough will
move eastward across the plains. Strong low-level CAA will cause a
surface ridge to build southward across the central plains into the
state of KS.
As the positive tilt H5 trough moves east into the central plains
there may be enough ascent behind ahead of the H5 trough and
behind the surface cold front for light snow showers or flurries
to develop through the night. Some areas may see a dusting of
snow. North winds of 15 to 25 MPH will make it even feel colder as
overnight lows drop into the mid to upper teens.
Wednesday, deeper moisture and stronger ascent across OK and TX will
cause a heavier wintry mix of precipitation to develop from north TX
and OK, east-northeast across AR and southern MO. The NAM model
shows a band of moderate snow developing through the day Wednesday
across northeast OK, extreme southeast KS and southwest MO. The
southeast counties may see periods of steady light snow through
the day. I would not be surprised if some areas across Coffey,
Anderson and Franklin counties receive a half inch to inch of
snowfall, especially if the NAM model verifies. Highs on Wednesday
will continue to be cold as temperatures only rise into the mid
20s to near 30 degrees. North wind of 15 to 25 MPH will once again
make it feel colder.
Wednesday night, the surface ridge axis will move southeast across
the CWA. Clear skies and light winds will allow overnight lows to
drop into the single digits and lower teens.
Thursday...the surface ridge axis will shift southeast into MO.
Light southerly winds will help to warm highs into the mid 30s to
around 40 degrees.
Friday through Saturday, the upper flow will become more zonal.
Expect highs to warm up to or slightly above normal. Highs on
Friday will reach the upper 40s to lower 50s, and highs on
Saturday will reach the lower 50s east to upper 50s west.
Sunday, a minor southern stream H5 trough will move east across
the southern plains Sunday night. Ahead of the H5 trough,
temperatures will warm once again into the mid to upper 50s. The
stronger ascent and deeper moisture ahead of the H5 trough will
remain well south of the CWA across eastern TX.
A weak cold front will move through the area Sunday night, which
will cool temperatures a few degrees on Monday with highs in the
upper 40s to mid 50s.
Looks like a big warming trend heading through the remainder of next
week as a broad upper level ridge amplifies across the plains. we
could see highs in the 60s and 70s by the middle and end of next
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1126 PM CST MON MAR 2 2015
IFR cigs advecting northward toward terminals and will carry as
prevailing through 12z. Have some improvement as potential rain
showers move through in the morning followed by some drier air
aloft breaking up clouds by mid morning. 3kft deck possibly lower
returns with frontal passage and continues through the forecast