Area Forecast Discussion
Issued by NWS Topeka, KS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
792
FXUS63 KTOP 211939
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
239 PM CDT Mon Oct 21 2019

.SHORT TERM...(This evening through Tuesday)
Issued at 230 PM CDT Mon Oct 21 2019

A deep upper low was located across northeast NE/northwest IA this
afternoon, with an upper level trough axis extending southward
across far eastern KS into east central TX. Wrap around moisture has
caused stratus to develop across much of the CWA. The cloud cover
has limited the deeper mixing of the PBL, and thus winds have
remained just below advisory criteria across north central KS. There
are some breaks in the overcast beginning to develop across north
central KS, which may lead to deeper mixing and better momentum
transfer to the surface for winds to increase to or just above
advisory levels. Some gusts across the southwest counties of the CWA
may approach 50 MPH through the remainder of the this afternoon.
Therefore, I`ll keep the wind advisory going through 7 PM.

Tonight, the stronger winds will gradually diminish through the
evening hours. The winds will remain around 10 to 15 MPH through the
night, thus given clear skies and lower dewpoints, temperatures will
only drop into the upper 30s to lower 40s.

Tuesday the upper low will shift northeast into the Upper Great
Lakes States as the upper trough axis moves east across the
eastern US. the central and southern Plains will remain in
northwesterly aloft. A broad ridge of surface high pressure will
build southeast from the central high Plains into OK and eastern
TX. Surface winds will veer more to the west as the center of the
surface ridge passes well south of the CWA. Highs will warm
slightly into the upper 50s to mid 60s.

.LONG TERM...(Tuesday night through Monday)
Issued at 230 PM CDT Mon Oct 21 2019

Tuesday night through Thursday night, an upper trough will dig
southeast out of western Canada and across the central Rockies, then
shear apart as it moves across the Plains. The southern section of
the H5 trough will become a closed upper low across western TX and
become cut off from the northern branch of the upper jet according
the ECMWF and Canadian models. The GFS keeps the southern stream
trough as an open wave. A cold front will move south across the CWA
on Wednesday, as low-level CAA across the northern Plains
develops as the northern branch of the H5 trough shifts east
across the northern Plains into the upper midwest. Northwest of
the front there may be enough weak isentropic lift along with
larger scale ascent, from the DCVA ahead of the positive tilt H5
trough axis, for light rain showers to develop Wednesday night
into Thursday. The best rain chances will be across the southeast
counties of the CWA. As the surface cold front pushes southward
across central and eastern TX, the better area of isentropic lift
and mid-level ascent will shift southeast of the CWA and the rain
showers will end Thursday evening. Highs on Wednesday, ahead of
the surface cold front will warm into the mid to upper 60s. As the
front passes southeast across north central and northeast KS
Wednesday afternoon, temperatures may begin to fall back into the
50s by the late afternoon hours. North winds, cloud cover and
scattered rainshowers will only allow highs on Thursday to reach
the upper 40s to lower 50s. Skies may clear late Thursday night,
allowing overnight lows to drop into the upper 20s to lower 30s.

Friday through Friday night, the ECMWF and Canadian model solution
show the closed upper low over west TX only drifting east across
west central TX through the day. The GFS solution shows a southern
stream upper trough moving east across central and eastern TX.
The stronger ascent will remain well south of the CWA, so we
should remain dry. Given more insolation, high temperatures will
warm slightly into the upper 50s to lower 60s.

Saturday through Saturday night, The ECMWF and Canadian models lift
the upper low northeast into OK and southern MO. The ECMWF is more
amplified and shows an area of stronger ascent ahead of the H5
trough moving across east central and northeast KS Saturday into
Saturday night. If the ECMWF verifies, then there will be a
chance for light rain Saturday into Saturday night. The Canadian
is less amplified and tracks the upper low a bit farther south of
the CWA, which would keep any precip across far southeast KS on
Saturday. The GFS has an open southern stream H5 trough which is
more progressive and shifts east across the southern US. If the
GFS were to verify, then Saturday will remain dry and warmer with
highs in the mid to upper 60s. All models show another upper
trough digging into the western US.

Sunday through Monday, the upper trough across the western US will
move east across the Plains. The GFS and Canadian are more
progressive than the ECMWF. The GFS moves the surface front across
the CWA Sunday morning with the stronger ascent ahead of the H5
trough remaining north and northeast of the CWA. While the ECMWF
solution amplifies the upper trough across the southwestern US and
does not bring the front southward across the CWA until Monday
afternoon. Both model solutions show dry conditions for most of the
area Sunday and Monday. Highs will be dependent on FROPA but expect
60s on Sunday and may be a cool down on Monday with mid to upper 50s.


&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1233 PM CDT Mon Oct 21 2019

The Broken Stratus at 4000 to 5000 feet will continue through he
afternoon hours. This may help to keep northwest winds to remain
under 25 KTS with gusts under 40 KTS the remainder of this
afternoon. The winds will gradually diminish through the evening
hours. However, northwest winds above 1000 feet will continue to
be in the 40 to 45 KT range through the early morning hours of
Tuesday. Therefore, all terminals may experience low-level wind
shear from 3Z TUE through 13Z TUE.


&&

.TOP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 7 PM CDT this evening for KSZ008-009-020>022-
034>038-054.

&&

$$

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



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