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FXUS63 KOAX 280437

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1137 PM CDT Mon Mar 27 2017

.SHORT TERM...(Tonight through Thursday)
Issued at 317 PM CDT Mon Mar 27 2017

Lucky people in northeast NE are getting glimpses of the sun, while 
the rest of us remain socked in under stratus. Subjective 12Z upper-
air analysis indicates an upper-level trough over MO/AR toward 
Arklatex, with another trough upstream over CA/NV toward the Pacific 
Northwest. Pattern is overall rather weak and wavy, with several 
shortwave ripples and lacking an upper-level jet stronger than 
100kt. The 850mb low was centered in eastern KS/northwest MO, with 
0C+ dewpoints wrapped around from the Great Lakes toward 
central/western NE and western CO.  Little cold air was noted behind 
the low, with a thermal ridge in the western US.  Surface low at 19Z 
was centered in southern MO/northern AR, with lee troughing already 
developing and with surface ridge axis from MN into eastern 
NE/eastern KS.

Main forecast concerns are what locations may see the sky and for 
how long, followed by a return of rain on Tuesday night. Clouds have 
eroded from SD into northeast NE, while stratus are hanging on from 
KLCG to KOLU and east/south.  As surface winds veer to more 
easterly, along with loss of daylight, it'll be hard to erode that 
cloud deck much further. Expect that the clouds will back into the 
area this evening, as supported by low-level RH progs among model 
solutions. Have kept us locked in stratus particularly in the 
eastern to southern CWA, with some break in the northeast to east 
central CWA before clouds re-invade. Could see some erosion also in 
the northern to northwestern CWA on Tuesday during the day, but 
moisture fetch does not support erosion in the same eastern to 
southern CWA area.

Upper low is progged to roll across the southern Plains on Wednesday 
and Thursday, bringing increasing rain chances. With low so far 
south, the instability also should remain south of the CWA, and have 
continued to keep thunder out of the forecast.  Forecast indicates 
little temperature change from lows to highs Tuesday night through 
Wednesday, which is reasonable given clouds and rain.  Given slow-
moving nature of low, many areas could see over an inch of much-
needed rain from Tuesday night through Thursday.

.LONG TERM...(Thursday night through Monday)
Issued at 317 PM CDT Mon Mar 27 2017

After that next round of rain and continued clouds, respite arrives 
Thursday night and Friday with at least a break in rain chances. 
Optimistically, could see clouds break, too ... but then again, with 
northeast to easterly low-level winds and a fair amount of low-level 
moisture, hesitate to get too optimistic.  The active upper-level 
pattern reloads for Saturday and Sunday, but as one would expect, 
model differences on the track of the weekend low present a wider 
envelope and thus lower confidence in details such as thunder 
potential and precipitation extent. Still do think airmass will be 
too warm for rain, though on the cool side as long as we remain on 
the north side of the ejecting trough/low.  Another break behind the 
low should provide respite again on Monday.


.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1140 PM CDT Mon Mar 27 2017

Cloud cover has been problematic through the evening. MVFR
ceilings cleared out of the KOMA area but should move back in the
next few hours. Also expect that MVFR ceilings will push back into
KLNK the next few hours and eventually to KOFK, but maybe not more
until toward 12Z. How much ceilings will increase Tuesday or if 
clouds will scattered back out again before precipitation moves 
in Tuesday evening is also a concern. Will stay fairly optimistic
in general. 




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