Area Forecast Discussion
Issued by NWS Topeka, KS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KTOP 231728

1128 AM CST Sun Nov 23 2014

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 356 AM CST SUN NOV 23 2014
Early this morning an upper level trough was moving into the the
high plains. An upstream upper level trough was lifting northeast
across eastern TX into AR and LA. The stronger 850mb moisture
advection was located from southeast TX, north-northeast to across
MO. Heavier rain showers were developing across western MO. Wide
spread light to moderate drizzle was occurring across much of the
cwa. The denser fog will remain well north and northwest of the CWA
this morning.

At 2 AM,  a surface cold front was moving southeast across central
NE, southwest across northwest KS into the northwest TX PNHDL. This
front will push southeast across the CWA during the late morning and
afternoon hours. Highs Today will occur just before FROPA, then
temperatures will fall through the 40s during the afternoon hours
behind the surface front.

The upper level trough across the high plains will slowly move east
across the state of KS Today and this evening. As the upper level
trough moves east, stronger ascent will cause widespread showers to
develop across north central KS late this morning these showers will
spread east across the CWA during the afternoon. The 00Z NAM and 00Z
ARP(WRF) both showed 200 to 400 J/KG of MUCAPE developing across the
warm sector ahead of the front. I would not be surprised is a few
weak isolated thunderstorms developed across the southeast counties
of the CWA during the afternoon hours ahead of the surface front.

A surface low across northwest OK will deepen slightly as it moves
east-northeast into southwest MO late this afternoon. The surface
pressure gradient across KS will tighten behind the front. Northwest
winds will increase to 20 to 30 MPH with some gusts of 40 MPH. Some
areas across the southern counties of the CWA may reach wind
advisory criteria for a few hours this afternoon into the early
evening hours. At this time the stronger surface winds will remain
across central and south central KS.

As the center of the H5 trough moves east across central KS this
evening, forecast sounding show vertical temperature profiles
cooling below freezing. However, the boundary layer may remain too
warm for snow. I added a slight chance for rain mixed with snow on
the trailing edge of the light precip across the CWA during the
evening hours. All the light precip will end before midnight when
surface temperatures will remain above freezing, thus no slick roads
are expected while the precip is falling. Any road surfaces that
remain wet late Tonight may freeze causing some icy spots, however
the stronger winds may dry road surfaces sufficiently to prevent any
ice from forming.

.LONG TERM...(Monday through Saturday)
Issued at 356 AM CST SUN NOV 23 2014

As the last lobe of energy rotates around the base of the upper
level northern stream trough...drying and subsidence in its wake
will overspread the cwa. There will be another weak shortwave trough
passage late Tuesday/early Wednesday...although it appears any
precipitation associated with it will remain north of the cwa. The
upper trough is not as deep by Thanksgiving Day as previous model
runs had as a result the degree of cold air advection
is also weaker. Following highs generally in the 40s through
Wednesday...only expect a slight cooldown into the 30s across the
northern cwa with the 40s persisting across the south. The overall
longwave pattern changes little into the weekend with a somewhat
zonal flow across the country. Will therefore maintain highs in the
upper 30s and 40s with a dry forecast continuing. Lows will
generally be in the 20s with some lower 30s.


.AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon)
Issued at 1118 AM CST SUN NOV 23 2014

Trend still appears to be for MVFR cigs and visby to continue,
with a band of IFR a few hours before the front passes at TOP/FOE.
Anticipate light rain will prevail, with a band of moderate rain
traversing the terminals through the evening hours. Rain ends late
evening and cigs lift to VFR around 3500ft. Rain/Snow mix appears
brief enough to remove mention in TAF.




AVIATION...67 is the U.S. government's official web portal to all federal, state and local government web resources and services.