Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
336
FXUS63 KOAX 201118
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
618 AM CDT Fri Apr 20 2018

.SHORT TERM...(Today through Sunday)
Issued at 259 AM CDT Fri Apr 20 2018

A very deep trough over the Utah-Arizona line was gradually
shifting east early Friday morning. This storm system has a
substantial area of diffluent upper level flow ahead of its track,
and upper level cloud cover has been steadily overtaking eastern
Nebraska and spreading into western Iowa. The cloud cover is
currently on the thin side, but has at least acted to stabilize
temperatures in the 30s early this morning. The surface pressure
gradient was also increasing over the high plains this morning,
with local winds turning out of the east and southeast, with
expectations of a gradual increase and a few gusts in the 15-20
mph range later today. All told, Friday will be pleasant with
highs expected to climb into the 50s or lower 60s. The primary
uncertainty regarding temperatures will be the thickness of the
mid/high clouds. Currently believe the clouds will be dense enough
by mid day to limit temperatures a bit, but if thinner could
potentially add 2-4 degrees to those highs...or receive the
opposite result if clouds are on the dense side.

By this evening, expect a gradual deepening of the moisture
profile and strengthening of the large scale ascent as the upper
trough drifts closer. A broad area of rain showers is expected to
slowly move east across Nebraska and neighboring states,
potentially reaching western counties in the forecast area in the
6-9 PM time frame. Low level flow will remain southeasterly, which
is a relatively dry source region and should inhibit rainfall
initially. Do see a pretty good chance for rain showers later on
in the night, mainly southwest of an Albion to Columbus to Lincoln
to Falls city line as the upper low reorganizes a bit farther to
the southeast. Any showers should taper off on Saturday morning
although cloud cover will remain for much of the day Saturday and
into Sunday. Even with the clouds, temperatures will be mild with
highs in the 50s on Saturday and back to the upper 50s or lower
60s on Sunday.

.LONG TERM...(Sunday night through Thursday)
Issued at 259 AM CDT Fri Apr 20 2018

Late Monday into Tuesday, a more compact trough is expected to
track across the northern two tiers of states in the CONUS, with
strong agreement among model guidance. This vorticity maxima is
then predicted to take more of a southeasterly track as it drops
into the longer-wave trough pattern over the eastern CONUS. As it
does so, see a good chance for scattered to widespread
precipitation across the forecast area. Temperature profiles would
currently point to rain as the precipitation type. There are some
indications of weak instability along the advancing cold front,
but not enough to suggest a likelihood of thunderstorms at this
point. Do expect windy conditions with this compact storm as it
crosses the region though. Northwest flow conditions are expected
to persist through the remainder of the forecast period with highs
likely holding below normal most days, but at least with some good
potential for highs in the 50s or lower 60s while lows hold in the
30s or lower 40s.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 618 AM CDT Fri Apr 20 2018

Prevailing VFR conditions are anticipated through the forecast
period. High-level clouds will increase today ahead of a strong
storm system moving into the Rockies. Winds will gradually
strengthen from the southeast by late morning then diminish by
early evening. There is a low-probability chance of light rain and
lower clouds (FL040) at KLNK between 06z and 12z Saturday.

&&

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

$$

SHORT TERM...Barjenbruch
LONG TERM...Barjenbruch
AVIATION...Mead



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.