Area Forecast Discussion
Issued by NWS Topeka, KS

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000
FXUS63 KTOP 240835
AFDTOP

AREA FORECAST DISCUSSION
National Weather Service Topeka KS
335 AM CDT SUN JUL 24 2016

.SHORT TERM...(Today and Tonight)
Issued at 335 AM CDT SUN JUL 24 2016

Last day of extreme heat potential today, with the realization of
the heat somewhat uncertain. The breaking down of the upper ridge
has allowed significant mid and high cloud into the area, with
periodic scattered convection developing. Recent uptick in coverage
in northeast Kansas seems to be ahead of a weak wave per RAP
analysis, but a more potent wave is evident on water vapor and radar
imagery was over east central Colorado. Surface observations showing
weak cold front pushing southeast into the state with modest though
persistent pressure rises behind it.

Expect scattered to broken mid and high cloud to dominate skies
today. Hard to rule out elevated precip for much of the area through
the day. Models weaken the nearer wave this morning, but bring the
Colorado wave into central Kansas in the late afternoon. Surface
front looks to stall out over central portions of the local area
this afternoon, with convergence along it rather weak, and an
obvious focus for precip along it is not apparent, but would expect
most coverage this afternoon and this evening to be near and north of
it. Northwest areas should see the most notable cooling compared to
recent days, but 850 and 925mb temp progs keep values near to
slightly above Saturday`s levels in the southeast. Despite the cloud
and precip potential, have followed the path of least regret and
kept highs in the middle and upper 90s along and south of I-70, with
some higher dewpoints pooling just north of the boundary. This keeps
apparent temps in the 103-107 range in this area and keeps the
Excessive Heat Warning going as-is. If these temps can be realized,
ML CAPEs near 2000 J/kg will bring some concern for isolated severe
downdrafts this afternoon and evening.

.LONG TERM...(Monday through Saturday)
Issued at 335 AM CDT SUN JUL 24 2016

Convection may be ongoing during the morning hours on Monday from
overnight convection. Most of the area should dry out for the rest
of the day An upper level shortwave through will move across
southern Canada and Northern Plains and Great Lakes region on
Sunday. This will suppress the upper ridge across the Central
Plains. The upper flow will gradually become west northwest Sunday
through Tuesday as the upper high pressure retrogrades into the
western U.S.. A series of upper shortwave troughs will move across
the Plains in the Wednesday through Friday time frame in a more
northwesterly upper flow regime.
A frontal boundary will move slowly into north central and northeast
Kansas on Sunday. Current consensus would keep the frontal boundary
across the northern counties and into parts of western and central
Kansas. This will keep much of the area in the warm sector for the
bulk of the day. Highs temperatures will range from the mid 90s to
around 100 south of the front with lower 90s to the north. Dew
points in the mid 60s in north central Kansas to the lower 70s in
east central Kansas will yield afternoon heat indices around 105
degrees, so will continue with the excessive heat warning through
Sunday evening. Expect scattered showers and thunderstorms to
develop along the front on Sunday in a weakly sheared environment.
Expect more pulse type storms with isolated heavy rainfall given the
high precipitable water content in the atmosphere. The frontal
boundary moves into east central or southeast Kansas on Monday as
high pressure moves southeast across Iowa. Expect some isolated to
scattered non severe convection and shear remains weak across the
area. As mentioned previously mid level shortwaves will move
southeast across the Central Plains from late Tuesday through
Friday. A frontal boundary will be present across parts of the
forecast area in north central and northeast Kansas through the
period. Expect the development of an MCS or two through this period
as well as convection along the frontal boundary. Timing of the
waves will be resolved in the future, so for now will keep chance
pops going in the forecast. Tuesday night and Wednesday look
favorable for higher precipitation chances early in the period when
a moderately strong wave is forecast to move across the area. Low
level jet interactions and isentropic lift along with good moisture
transport will increase the chances of training storms and locally
heavy rainfall. Monday and Tuesday highs are expected to be near
seasonal values in the lower to mid 90s, then cool into the 80s to
lower 90s Thursday and Friday. Lows mainly in the upper 60s to lower
70s.as high pressure builds south into northeast Kansas. The
frontal boundary will stall along the Oklahoma border in the
afternoon and should focus convection there in the afternoon and
evening. The western portion of the front will move northeast as a
warm front across western and central Kansas. The low level jet of
25 to 30 kts is forecast across western Kansas into western
Nebraska. Precipitation chances remain low Monday night into Tuesday
with the front south of the CWA and the moisture advection remaining
to the west and northwest of the forecast area. Tuesday night a
shortwave will move southeast out of Wyoming and southeast into Iowa
Wednesday morning. The front is forecast to lift northeast as a warm
front Tuesday night and should extend from south central South
Dakota into northwest Missouri by Wednesday morning. Some elevated
storms will be possible as the front lifts northeast, however the
better forcing will remain north across Nebraska. An MCS may form
and move southeast and clip parts of northeast Kansas, so will keep
highest precipitation chances across the northeast. A wave is
forecast to move across Kansas and Nebraska Wednesday night in the
northwest upper flow. A frontal boundary will lay across southern
Nebraska however there is not much in the way of convergence along
the front and the low level jet veers to the southwest and remains
under 20 kts. Another upper trough is expected to move southeast
across the Plains Thursday night which will bring a cold front
through the CWA as it does so. The front looks to stall in southern
Kansas. Small chances for precipitation will remain into the weekend
with occasional waves affecting the Central Plains, however the
deeper moisture will be across Oklahoma and southern Missouri late
in the week. Cooler temperatures are expected in the medium and
extended period with highs in the 80s to low 90s. Lows int he lower
70s cooling into the 60s toward the end of the week and into
Saturday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1142 PM CDT SAT JUL 23 2016

A VFR forecast is expected to persist through Sunday. Models
continue to show a marginal chance for LLWS with low level winds
around 30KT. Surface obs across central KS are gusting now
suggesting the nocturnal inversion is not that strong which is
also limiting the chances for LLWS. Otherwise the main focus is on
precip chances. There are some timing differences among the
various solutions. Therefore have maintained a PROB30 for what
appears to be the most likely window for precip.


&&

.TOP Watches/Warnings/Advisories...
Excessive Heat Warning until 7 PM CDT this evening for
KSZ021>024-026-034>040-054>056-058-059.

&&

$$

SHORT TERM...65
LONG TERM...53
AVIATION...Wolters



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