Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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FXUS63 KEAX 311141

641 AM CDT FRI JUL 31 2015

Issued at 419 AM CDT FRI JUL 31 2015

Today - Saturday Night:

Primary upper trough entrenched from Hudson Bay into the Mid
Atlantic States while elongated dome of high pressure extends from
the intermountain region into the Southern Plains. These features
will persist through the weekend. The southern fringe of a belt of
faster mid/upper level winds within the northwest flow extends from
SD/NE through IA/IL. Within this band of stronger flow am
anticipating one or two weak/poorly defined impulses will slide
southeast, passing close enough to the CWA to warrant some low end
chance PoPs. However, since these features are typically nebulous
and like finding a needle in a haystack have low to medium
confidence on timing and location of any convection.

Overnight satellite/radar data show a small cluster of storms invof
OMA. Activity is likely tied to weak isentropic ascent on the 310K
surface. Don`t see any discernible frontal boundary to tie into the
convection. Expect this activity to linger past sunrise but
eventually fall apart before reaching northern MO. However, this
isentropic ascent on the 310K surface manifests itself this
afternoon over eastern NE. Aided by moderately high CAPEs between
2000-3000 J/kg and 25-30kt of 0-6km shear expect scattered
strong/possibly severe convection to form and slide southeast into
northern MO. However, activity will likely weaken after sunset with
loss of heating/instability. So, will only use low end chance PoPs.

Saturday night may be more problematic from a severe potential as
the nocturnal low-level jet forms across KS into eastern NE while
the isentropic ascent on the 310K surface shifts more into IA and
far northern MO. Aided by similar instability parameters and a bit
stronger 0-6km shear and fueled by the low-level jet believe there
is a better chance for more organized severe thunderstorms over
northern MO.

Seasonal temperatures with a slight uptick in dewpoints are expected
through Saturday.

Sunday - Monday:

The overall pattern aloft really doesn`t change much with northwest
flow still present while a weak cold front tries to sink south
through IA into northern MO on Monday. Have some low chance PoPs on
Monday across northern MO to account for this possibility.
Otherwise, dry, very warm and increasingly humid over the rest of
the region.

Tuesday - Thursday:

This period looks a bit more active as the aforementioned cold
front drops south into the CWA. How far south is open for debate as
the operational models build the upper high back towards the Central
Plains. If this were to occur it should limit the southern push of
the cold front. Due to the proximity of the boundary and a
moist/unstable airmass in place think 30-50% PoPs are reasonable.
After Tuesday the temperature forecast is fairly uncertain due to
confidence issues on placement of the cold front. So, have used the
blended model approach.


.AVIATION...(For the 12Z TAFS through 12Z Saturday Morning)
Issued at 634 AM CDT FRI JUL 31 2015

Except for patchy river valley fog that will burn off within the
first hour of the forecast expecting VFR conditions to continue.
Widely scattered convection is possible over northern MO later this
evening and through the overnight hours. Most likely any storms will
miss the Kansas City terminals with only a very small chance of
convection at KSTJ.




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