Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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000
FXUS63 KOAX 291121
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
621 AM CDT Sat Jul 29 2017

.SHORT TERM...(Today through Monday)
Issued at 331 AM CDT Sat Jul 29 2017

Little change is needed to the current forecast of mild temperatures
and sparse precip chances into early next week.

Mid level flow pattern this morning features a low dropping
southeast through the Ohio Valley, and a sprawling high from the
Southern Plains through the Southwest. Ohio low and associated
trough extending into the southeast states is forecast to drift
southeast to off the Atlantic Coast on Sunday, which allows western
high to build east into the Plains. Thus gradually increasing
heights are expected over our area, suggesting some potential for a
slight warming trend into early next week.

However surface high pressure extending from the western Great Lakes
into the Mid Missouri Valley region is expected to persist through
Monday, effectively tempering maximum warming potential from
building ridge aloft. In fact, GFS shows 850 temperatures remaining
in the 14-18C range across eastern Nebraska and southwest Iowa
through the period, with only minor fluctuations each day. Surface
winds will remain fairly light and favor a southeast direction
through Monday, keeping low level mixing to a minimum. This all
points to a forecast of persistence over the next several days, with
cloud cover or lack thereof affecting temperatures by a few degrees.

Precipitation chances appear to be rather low through the period,
with no major systems to key on. A mid level wave did roll through
the region on Friday and produced some sprinkles or light rain from
mid level clouds. That could occur again today as another ripple
drifts from the High Plains into our area. Perhaps the best chance,
albeit small, for precip will come later tonight and Sunday in
northeast Nebraska where GFS suggests mid level shortwave may
trigger scattered showers.

.LONG TERM...(Monday night through Friday)
Issued at 331 AM CDT Sat Jul 29 2017

Amplification of eastern trough will occur during the week, bringing
northwest to north upper flow to the central CONUS by mid to late
week. The result for our area will be a trend toward cooler
temperatures and off-and-on precipitation chances.

Tuesday will likely be the warmest day of the week as deepening
shortwave in the Northern Plains pushes a cold front into the
Dakotas. Southwest low level flow ahead of it should help push highs
closer to 90 then. Then shortwave is expected to amplify as it drops
toward the Great Lakes, and eventually carves out mid level trough
over the eastern two-thirds of the country. Initial precipitation
chances will come Tuesday afternoon and night in northern Nebraska
as cold front approaches. Then those chances spread south through
eastern Nebraska and southwest Iowa as front settles through the
region. Cooler air characterized by 850 temperatures near 10C will
spill south behind front, suggesting temperatures closer to 80 will
be the rule by Thursday and Friday. Also, models suggest a couple of
mid level shortwaves embedded in northerly flow could trigger post-
frontal showers and a few thunderstorms at just about any time
through the end of the week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 609 AM CDT Sat Jul 29 2017

VFR conditions will prevail thru the fcst pd.

&&

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

$$

SHORT TERM...Dergan
LONG TERM...Dergan
AVIATION...DEE


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