Area Forecast Discussion
Issued by NWS Topeka, KS

Home | Current Version | Previous Version | Graphics & Text | 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
000
FXUS63 KTOP 031141
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
641 AM CDT THU SEP 3 2015

...Update to aviation forecast discussion...

.UPDATE...
ISSUED AT 635 AM CDT THU SEP 3 2015

Weak isentropic lift at the 310K theta surface was causing just
enough lift for parcels around 700mb to reach their LFC`s for
showers to develop. There may be just enough elevated
instability for some elevated thunderstorms as well. The best
chance for elevated showers and thunderstorms will be north of
I-70 across northeast KS. The showers should diminish as the
isentropic lift weakens towards 9 AM.

&&


.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT THU SEP 3 2015

An upper level ridge will remain nearly stationary across the
southern and central plains for the next 24 hours as an upper level
trough across the pacific northwest amplifies southward along the
west coast. Most of the weak upper level troughs embedded within the
southern stream jet should move north-northeast around the western
periphery of the upper ridge axis across the high plains.

Early this morning the stronger isentropic lift will occur north of
the CWA across south central and central NE where elevated showers
and thunderstorms may develop towards sunrise. There may be enough
weak isentropic lift for an isolated shower across the CWA early
this morning. I will keep pops in the 10 to 14 percent range just
in case an isolated high based shower manages to develop.

After a some mid level clouds in the morning, skies should become
mostly sunny. Highs once again should reach the lower to mid 90s
across the CWA with the higher temperatures across the western and
southwest counties of the CWA. Southerly winds will increase to 10
to 20 MPH with gusts of 25 to 30 MPH during the late morning and
afternoon hours.

Tonight, Skies will be mostly clear with overnight lows dropping
back into the upper 60s to lower 70s.

.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 301 AM CDT THU SEP 3 2015

On Friday and Saturday a strong mid/upper low pressure will dig
across the Pacific northwest and northern Rockies. Southwest flow
aloft will become well established over the northern plains. Weak
mid-level shortwaves embedded within the southwest flow aloft will
track west and north of the forecast area. Any activity associated
with these waves should stay out of the area with the exception of
north central KS. Depending on the exact track of these waves there
is a slight chance a more easterly track could bring a few showers
or storms to north central KS especially Saturday night. Sunday into
Monday the strong mid-level system will lift northeastward over the
northern plains and southern Canada. This will push a front into the
forecast area either late Sunday afternoon or early evening, and
continue to slide southeastward through the area overnight Sunday.
The GFS is depicting that MUCape will be on the order of 500 j/kg
while the deep layer shear remains around 25 kts. So expect storms
will develop along the front although it appears the environment
will not support any severe storms at this time. Monday the front
stalls out in or just south of the forecast area only to lift back
northward Monday night driven by another mid-level shortwave
tracking over the northern plains and several weaker waves coming
out of the southwest US. Although the models disagree on how to
handle this second piece of energy dropping into the backside of the
initial trough. Then on Wednesday another front could push
through the area after a brief period in the warm sector, but
confidence in this scenario is low at this point due to model
discrepancy. Temperatures will continue to stay warm, with highs
in the 90s and lows in the 70s, until the front and precip arrives
late weekend and into early next week.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Friday MORNING)
ISSUED AT 635 AM CDT THU SEP 3 2015

Any isolated showers or thunderstorms will remain north of the
terminals early this morning. Expect VFR conditions.

&&

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

$$

UPDATE...Gargan
SHORT TERM...Gargan
LONG TERM...Sanders
AVIATION...Gargan


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