Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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FXUS63 KOAX 191135

Area Forecast Discussion
National Weather Service Omaha/Valley NE
635 AM CDT THU MAY 19 2016

.SHORT TERM...(today through Saturday)
Issued at 335 AM CDT Thu May 19 2016

00z upper-air analysis revealed a split-flow pattern present over
the CONUS with the primary feature of interest being a Pacific
Northwest short-wave trough which will evolve into a major
western U.S. trough over the next 24 to 48 hours. A lower latitude
perturbation over the southern High Plains early this morning
will track into Kansas today, yielding some increase in clouds
across the forecast area. In the low levels, a deepening lee
trough over the High Plains will promote gusty south winds by
afternoon with highs generally around 70.

The Kansas impulse will shift to our southeast tonight with considerable
mid-level ridging forecast Friday over the Great Plains,
downstream from the amplifying western U.S. trough. This upper-air
pattern configuration will maintain a lee trough over the High
Plains with gusty south winds again expected, especially over the
northwestern portion of our area. Temperatures should be similar
to that on Thursday; around 70 or the lower 70s.

A mid-level impulse skirting the eastern periphery of the building
Great Plains ridge will translate from the upper Mississippi
Valley to lower Ohio Valley Friday night into Saturday. Outside
of some increasing clouds, this feature will have little impact on
sensible weather in our weather. The lower troposphere will
continue to warm with the prevailing southerly low-level winds,
yielding highs in the mid 70s.

We will see gradually warmer overnight lows into this weekend,
largely due to the effects of increasing low-level moisture

.LONG TERM...(Saturday night through Wednesday)
Issued at 335 AM CDT Thu May 19 2016

The western U.S. trough will edge east toward the Great Plains
this weekend with the 00z ECMWF and GFS suggesting that an upper-
level jet streak and leading vorticity lobe will pivot through the
northern Plains Sunday into Sunday night. Meanwhile, an associated
cold front will advance into the mid Missouri Valley late Sunday
night into Monday, supporting an increased chance of showers and
thunderstorms along it.

With the passage to the lead impulse through the north-central
States, southwesterly mid-level flow will become established from
the Rockies into Great Plains. This will promote lee cyclone
development over the central High Plains during the early to
middle part of next week. Meanwhile, the above-mentioned cold
front is expected to stall before becoming aligned in west-to-east
fashion over the central Plains. This large-scale pattern
evolution will set the stage for multiple days of thunderstorm
chances, and possibly some severe weather. Stay tuned!

Expect daytime highs in the mid 70s to lower 80s with lows in the
50s to lower 60s.


.AVIATION...(12Z TAFS for KOMA...KLNK...KOFK through 12Z Friday)
Issued at 633 AM CDT Thu May 19 2016

Mainly VFR conditions are forecast through much of the TAF period
as scattered to broken mid level clouds near FL070 will prevail.
South winds of 10 to 20 kt are expected, and could gust to 25 kt
near KOFK. MVFR cigs will likely move into central Nebraska after
06Z, and could reach KOFK and KLNK just before the end of the TAF


.OAX Watches/Warnings/Advisories...


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