Area Forecast Discussion
Issued by NWS Topeka, KS
FXUS63 KTOP 252325
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
525 PM CST Sun Jan 25 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Monday)
Issued at 244 PM CST SUN JAN 25 2015
Water vapor imagery showed the shortwave trough sliding across
Missouri this afternoon as it progressed toward the Ohio River
Valley. The associated surface low was situated over southern
Illinois with a tight pressure gradient extending into central and
eastern Kansas. As a result, north-northwesterly winds were gusting
upwards of 35-45mph through early this afternoon but will gradually
diminish through mid to late afternoon as the surface low and
associated pressure gradient shift further to the east. Expansive
cloud cover from this passing system provided good insolation today,
keeping conditions cooler as temperatures struggled to warm much
from this morning`s low temperatures. As a result, afternoon high
temperatures should only peak in the low/mid 40s and possibly into
the upper 40s near central Kansas.
These low clouds may be a bit slow to clear out overnight, so
trended a couple of degrees warmer for temperatures tonight with lows in
the upper 20s/low 30s. A weak ridge of surface high pressure will
slide across the area tonight before another area of surface low
pressure and associated surface trough track southward into the area
by mid-day Monday. Only expect some scattered low/mid clouds from
this passing trough with winds veering from southwest to northwest
by the afternoon. A modest thermal ridge should set up over the High
Plains with decent downslope winds aiding in a return to well
above-normal temperatures. Expect high temperatures to reach into
the low to mid 60s from east to west.
.LONG TERM...(Monday Night through Sunday)
Issued at 244 PM CST SUN JAN 25 2015
Monday Night though Tuesday Night...
An upper level ridge across the southwestern US will move across the
central and southern plains on Wednesday.
Monday Night through Tuesday, A surface ridge of high pressure
across eastern KS Tuesday night will shift east into MO by the
afternoon hours of Tuesday. Light easterly winds will gradually back
to the southeast through the day as the surface ridge axis moves
east into MO.
Stronger WAA at the surface and 850mb across western KS will shift
east across central KS during the afternoon hours. The southwest
counties of the CWA will warm into the upper 60s as deeper mixing
and 850mb temps increase to 14 deg C. The mixing will not be as
deep over the northeast counties of the CWA, thus highs will only
reach the mid to upper 50s.
Tuesday Night through Wednesday, A weak upper level trough will
round the H5 ridge axis across the southern and central plains.
There may be enough ascent to see an increase in the high and mid
cloud cover during the day on Wednesday. A lee surface low will move
east across KS during the day. A weak cold front will move southeast
across north central KS during the afternoon hours. The warmest
temperatures will occur ahead of the surface cold front during the
afternoon hour across east central KS where highs should reach the
mid to upper 60s. The northern counties will only see highs in the
lower 60s as winds shift to the northwest.
Wednesday through Sunday...
Wednesday through Wednesday evening, a shortwave and associated
surface low will skim northern Kansas. Models are still in
agreement that no precipitation will be seen with this weak frontal
passage, as the mid levels of the atmosphere remain too dry even
though there is weak lift present. A north-south temperature
gradient will be in place Wednesday with highs ranging from the
lower 60s in the north, to mid/upper 60s in the southern portion of
our area. As the shortwave passes through Wednesday night, winds
veer to the north allowing for cooler temperatures Thursday.
Models have come in slightly better agreement for the overall
pattern Friday evening into Saturday. A cutoff low will develop
over Southern California, while NW flow will develop from Canada
streaming into the northern Plains. Energy from this southern
system is being picked up on both the GFS/ECMWF barely skirting the
southwest most edge of the CWA on Friday night, but have kept a dry
forecast for now due high uncertainty of how this split flow
scenario plays out.
As for temperatures this weekend, Saturday and Sunday look similar
in that highs should top out in the mid 40s both days. Saturday
looks to be cloudy all day while skies should clear Saturday night
allowing for some sunshine to come through partly cloudy skies on
.AVIATION...(For the 00Z TAFs through 00Z Monday Evening)
Issued at 523 PM CST SUN JAN 25 2015
MVFR cigs early at TOP/FOE then VFR after 05z through the forecast
period. Wind gusts diminish in next hour or so. Winds do shift
around to the southwest then back to the northwest tomorrow as a
system passes, but until middle afternoon expect speeds to be AOB