Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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FXUS63 KOAX 190900
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
400 AM CDT Wed Apr 19 2017

.SHORT TERM...(Today through Friday)
Issued at 359 AM CDT Wed Apr 19 2017

88D mosaic showing elevated convection mainly over the southern CWA
along deep moisture convergence axis extending from s-cntrl Neb into
southern IA. Trends over the last few hours indicate thunderstorm
activity will continue pushing eastward through the CWA during
the early morning hours before exiting the area toward late
morning.

For today...surface low centered over eastern CO will gradually lift
into eastern Neb/western IA later this afternoon allowing stalled
boundary currently extending along Neb/KS border to lift
northward as a warm front into central IA. Meanwhile, trailing
cold cold will be advancing southward through Neb. A moisture rich
environment...PWS 1.75"...will be in place allow for quick
destabilization...MLCAPES 1500-200 J/kg...during peak heating
hours. Storms are progged to fire on edge of CAP late this
afternoon with development expected generally along/south of I-80
on nose of 0-3km lapse rates coincident to axis of strengthening
boundary layer theta-E convergence.

Instability/deep layer shear will favor supercell development over
the southern CWA. Environment will be prime for large hail given
very steep mid-layer lapse rates atop moist boundary layer. In
addition...SRH should be adequate to pop off a few tornadic storms.
However...RAP13 hodographs show a more favorable environment to
produce tornadic storms will be found just east of the CWA/northeast
of the surface low where sfc-6km shear/ML SRH/instability will be
most prevalent. Storm activity should be coming to a close then
toward midnight.

Dry and bit cooler conditions expected heading into this weekend.


.LONG TERM...(Friday night through Tuesday)
Issued at 359 AM CDT Wed Apr 19 2017

GFS/CMC/ECM pcpn chances appear minimal during the extended periods
with better chances mainly north of the CWA with highs generally in
the mid 60s and lows in the mid 40s.

&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1214 AM CDT Wed Apr 19 2017

A strong low level jet is taking aim at southeast Nebraska
tonight and Wednesday morning. With deep moisture pooled along the
h85 front...showers and thunderstorms south of KLNK will increase
tonight. As the front lifts north...so too will the
precipitation. Mention showers and tsra at all TAFS sites. Some
hail could accompany the stronger thunderstorms. Surface low
pressure and a cold front pushes across southeast Nebraska and
southwest Iowa during the late afternoon and early evening.
Depending on the wind field and destabilization...strong to severe
thunderstorms could redevelop and affect KLNK/KOMA. VFR cigs to
start...then MVFR with the precipitation and into Wednesday
morning. KOFK on the cool side of the front should remain MVFR/IFR
Wednesday afternoon.


&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&

$$

SHORT TERM...DEE
LONG TERM...DEE
AVIATION...Zapotocny


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