Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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FXUS63 KOAX 230432
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1132 PM CDT MON AUG 22 2016

.SHORT TERM...(tonight through Thursday)
Issued at 310 PM CDT MON AUG 22 2016

Main issues to contend with is pcpn chances along with severe storm
potential Tuesday aftn/evening.

Model maintain advertising a progressive pattern over the next
several days with a series of shortwave trofs traversing the
U.S./Can border along with several pieces of energy ejecting out of
the swrn conus and into the central plains.  Have noted though that
models are differing with impulse of concern that will be associated
with convective development Tuesday afternoon...NAM is much stronger
as opposed to weaker GFS.

At any rate...aforementioned impulse ejects out of the swrn conus
and pushes into the cntrl plains by 18z Tuesday. In the
meantime...instability parameters ramp up quickly with onset of
strong low level theta-E advection with convection breaking out in
the vicinity of stout boundary layer moisture convergence situated
on the  western periphery of the CWA. Both NAM12/GFS20 suggest TSRA
initiation Tuesday afternoon sometime between 18z-21z...while the
ARW/NMM hold off development sometime between 21z-24z. As far as
severe storms...overlapping parameters MUCAPE 2500J/KG...effective
shear 35-40kt...suggest good potential for supercell development.
However...have noted that deep layer 0-6km shear is relatively weak.
In addition to this...stout effective SRH suggests one or two
tornadic storms cannot be ruled out.

There is general model agreement though that the potential will be
high for locally heavy rainfall through early Wednesday morning over
the northern CWA where MaxOmega/high PWS concentration/deep warm
cloud layer will phase on nose of llvl jet.

Otherwise...a cooling trend is on tap the next several days in
response to northern stream shortwave drags a cold front into the
central plains with the leading edge of progged to cross thru the
CWA late Tuesday night/early Wednesday morning. Expect pcpn activity
to gradually subside from north to south then through Thursday.

Cooler conditions will prevail then with below normal highs by mid
week.

.LONG TERM...(Thursday night through Monday)
Issued at 310 PM CDT MON AUG 22 2016

A lifting warm front in conjunction with nocturnal llvl jet/strong
theta-E advection is progged to induce pcpn over the CWA Friday
night with additional pcpn activity possible the rest of next
weekend and early next week in association with several impulses
ejecting out of the swrn conus into a moisture rich/unstable
environment. Did note however how ECM vort energy is much more stout
than the GFS. Going fcst looks on track with small POPs in
place...thus no major changes anticipated. Too far out at this point
to have feel for severe potential. Otherwise...max temps rebound
this weekend into the mid 80s.

&&

.AVIATION...(06Z TAFS for KOFK...KLNK and KOMA.)
Issued at 1130 PM CDT MON AUG 22 2016

VFR conditions are expected to prevail through 18z with high
level cirrus cig across the region in advance of short wave trough
approaching from the desert southwest. After 18z potential for
thunderstorms will increase as surface cold front approaches and
short wave moves across the region with areas of MVFR cigs and
vsby in areas of convection.

&&

.OAX Watches/Warnings/Advisories...
NE...None.
IA...None.
&&

$$

SHORT TERM...DEE
LONG TERM...DEE
AVIATION...Fobert



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