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000 
FXUS63 KTOP 241700
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1200 PM CDT Sat Aug 24 2019

...AVIATION UPDATE...

.SYNOPSIS...
Issued at 344 AM CDT Sat Aug 24 2019

Recent water vapor imagery showing a pair of upper troughs upstream 
of eastern Kansas, with a few clusters of convection associated with 
the eastern trough over eastern Colorado, and the second feature 
pushing east-southeast across Wyoming. At the lower levels, broad 
and deep easterly flow continues over the mid-Mississippi Valley 
under the expanding upper ridging centered over the western Great 
Lakes, with more veered flow to the west helping support the 
overnight convection. A few areas of isolated shallow convection 
have impacted the local area in areas of modest isentropic upglide 
in the moist lower troposphere sampled by the 0Z TOP sounding.

&&

.SHORT TERM...(Today through Sunday)
Issued at 344 AM CDT Sat Aug 24 2019

Recent radar trends suggest a more northward push to the remnant 
MCS to the west and the main wave with this feature does translate 
north of the region today, but the wave axis does bring somewhat 
better forcing than the overnight hours and expect isolated to 
scattered shower and perhaps some modest thunderstorm activity for 
the daytime hours. Lower cloud has slowly developed again across 
southern and western portions of the CWA and will likely continue to 
fill in over the next several hours before dispersing with diurnal 
trends today. The cloud and precip potential should keep 
temperatures somewhat cooler than Friday, with a rise of around 10 
degrees anticipated. 

The second wave dives southeast into eastern Colorado this afternoon 
with another round of convection expected to from into adjacent 
portions of Kansas. Although steering winds should keep the bulk of 
these storms to the southwest, there is small potential for far 
southwestern locations to be impacted by the expected MCS. 
Organization of the system could bring some strong winds and 
possibly near-severe hail. Broad though weakening forcing with the 
wave passes overnight into early Sunday for some precip potential 
for the entire area during these periods. Low levels again remain 
rather damp but modest afternoon subsidence and a more southerly 
wind component should provide a slightly warmer day for western 
areas.

.LONG TERM...(Sunday night through Friday)
Issued at 344 AM CDT Sat Aug 24 2019

Attention turns to a larger-scale trough digging southeast across 
the northern Plains Sunday night into Monday, dragging a cold front 
through the area Monday afternoon and evening. The overall slower 
solution allows for a more unstable atmosphere to develop ahead of 
the boundary with dewpoints likely returning to the middle 70s in at 
least east-central Kansas and ML CAPE values nearing 4000 J/kg, but 
a moderate southwesterly low-level jet ahead of the front brings a 
moderate EML over the area Sunday night into early Monday. Forecast 
soundings are similar with the resulting capping diminishing 
adequately for at least isolated convection to form. With mid-level 
winds of around 40 knots from the west-northwest, the shear/CAPE 
combination would support severe storms, though the lack of upper 
forcing in addition to the capping and some morning stratus 
potential keeps some uncertainty in place on severe weather. 

Precipitation chances beyond Monday night are largely on the low 
side with expansive surface ridging building from the northwest 
behind northwest flow aloft. Better insolation offsets the cooler 
850 mb temps to keep highs fairly close to this weekend's 
expectations. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1200 AM CDT Sat Aug 24 2019

Easterly low level flow is expected to persist through Sunday 
with no appreciable dry air advection. So low clouds are forecast
to remain over the terminals. An MCS is progged to move southwest
of the terminals overnight. The remnant MCV may cause some shower
activity through the morning Sunday. So think MVFR conditions
through the afternoon will give way to IFR CIGS late tonight with
showers becoming more probable. 

&&

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

$$

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