Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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FXUS63 KOAX 140830

Area Forecast Discussion
National Weather Service Omaha/Valley NE
330 AM CDT Sat Apr 14 2018

.SHORT TERM...(Today through Monday)
Issued at 330 AM CDT Sat Apr 14 2018

Blizzard conditions and snow amounts are the primary forecast
concerns in the short term.

Very dynamic system continues to spin near the KS/NE border area
early this morning as shown in water vapor satellite imagery.
System did bring some thunderstorms to parts of the area in the
past 18 hours, mainly in southwest IA. Main 850 mb moisture axis
extended from the Gulf coast into MO last evening. Low was nearly
stacked at 700 mb and 500 mb last evening over southwest NE with
an area of height falls of 100 meters or more stretching from the
TX panhandle toward north central KS. At 300 mb, jet segments of
115 knots were noted from OK into KS and another was back over UT.
Surface analysis at 3 am showed a weakening low pressure center
over southeast NE with main low now over northern MO. Temperatures
were in the 30s across northeast NE with 40s elsewhere in the
local area, but readings were in the upper teens to upper 20s in
much of western and central NE.

Dry slot has been over much southeast NE and southwest IA since
mid to late evening yesterday, with a few convective elements
forming in IA and northeast NE. Snow amounts so far have been
fairly light with more sleet than snow in the northern parts of
northeast NE. As the main surface low tracks east and the mid
tropospheric low also tracks east, we should see an increase in
precipitation coverage. Some model guidance is suggesting a that a
second deformation zone will form from southeast NE into southwest
IA. So...did increase QPF a bit there but not as high as what the
00Z GFS showed. Temperatures have been a bit cooler than expected
for parts of the area early this morning. The NAM seemed to be
doing a decent job so trended readings toward a blend of the NAM
and some of the high resolution short range models. Forecast
soundings show some elevated instability with fairly steep mid
level lapse rates. This suggests some convective type precip may
occur with rain/sleet/snow the most likely outcomes. There is some
chance of freezing rain but at this time it does not look to be a
major impact. Winds will be increasing and that will need to be
monitored too. Wind gusts have been over 50 knots in parts of
central NE early this morning.

For headlines, kept the blizzard warning and winter storm warnings
in the same locations as earlier but added some counties to the
winter weather advisory. Will need to keep an eye on radar trends
and precip type today. Snow intensity will decrease from west to
east tonight, but may linger even into Sunday morning across
western IA, then Sunday night and Monday should be dry. Lows
tonight should range from around 20 to the lower 20s. If winds
drop off and clouds clear more than expected in northeast NE we
may have to decrease lows there. Looks for highs Sunday only in
the lower and mid 30s. Highs will warm on Monday with at least
partial sunshine to 40s north and upper 40s to lower 50s south.

.LONG TERM...(Monday night through Friday)
Issued at 330 AM CDT Sat Apr 14 2018

Our next chance of rain moves in by late Tuesday with a system
that moves out of the Rockies toward the northern Plains. This may
bring moderate precip amounts with rain south and a mix of rain
and snow north. Snow amounts expected to be light at this time.

There is another system that should move out in the central parts
of the Plains Friday into Saturday. This could be somewhat similar
to yesterday and today, but probably with less snow.


.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1147 PM CDT Fri Apr 13 2018

A vigorous deep-layer cyclone will slowly track through southeast
NE early Saturday morning and into northwest MO by Saturday
evening. Mosaic radar data as of 0430z indicate the primary
deformation band situated over central into western NE with light
showery precipitation noted across portions of northeast NE.
Expect the deformation band to steadily shift southeast in tandem
with the parent synoptic system. KOFK is already indicating IFR
conditions due to low clouds and snow with prevailing LIFR
ceilings and visibilities becoming more probable after 12z
Saturday. Precipitation should begin in earnest at KOMA and KLNK
toward 12z Saturday, likely in the form of rain initially. With
time the rain could mix with sleet before changing over to snow by
Saturday afternoon. Here too, prevailing IFR to LIFR conditions
can be expected with the onset of precipitation. Winds will
steadily increase from the north-northeast with the passage of the
surface low to the southeast of the area.


NE...Winter Weather Advisory from 9 AM this morning to 7 PM CDT this
     evening for NEZ045-052-053-066>068-078-088>090-092.

     Blizzard Warning until 7 PM CDT this evening for NEZ015-033-043-

     Winter Storm Warning from 7 AM this morning to 7 PM CDT this
     evening for NEZ034-044-051.

     Blizzard Warning until 7 PM CDT this evening for NEZ011-012-

IA...Winter Weather Advisory from 9 AM this morning to 7 PM CDT this
     evening for IAZ055-056-069-079.

     Winter Storm Warning from 7 AM this morning to 7 PM CDT this
     evening for IAZ043.



LONG TERM...Miller
AVIATION...Mead is the U.S. government's official web portal to all federal, state and local government web resources and services.