Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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876
FXUS63 KOAX 270850
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
350 AM CDT FRI MAY 27 2016

.SHORT TERM...(today through Sunday)
Issued at 350 AM CDT Fri May 27 2016

Will go ahead and cancel the flash flood watch that was scheduled to
expire at 12z. Some streams in southeast Nebraska and southwest Iowa
have seen flooding...but it does not appear that widespread high
rainfall amounts will occur this morning. The main forecast
concerns will be in regards to thunderstorm chances...potential
severe storms and rain amounts through Saturday.

Large scale pattern features a mid tropospheric trough from Manitoba
down into the four corners region. Water vapor imagery early this
morning showed one closed low over eastern Colorado and another in
northern North Dakota. Highest precipitable water values and 850 mb
dewpoints (10-17 degrees C) were down across Kansas and Missouri.
Surface analysis was fairly complex due to outflow from numerous
thunderstorm complexes earlier in the night...but primary low was
over northwest Oklahoma. A weak front seemed to extend from another
low in northern South Dakota to western Kansas and then down to the
low in Oklahoma. Dewpoints in our area were in the mid 50s to lower
60s. Storm chances will linger into Saturday evening...then we may
get a dry period from later Saturday night into Sunday morning.
Timing of this will be tied to the progression of the Colorado
closed low lifting up toward Minnesota by midnight Saturday night.
By that time...a shortwave trough will be over southern California
with a stronger trough moving toward the Pacific Northwest.

Today...overall coverage of showers and storms should be fairly
low with main complex near the Kansas/Missouri border as of
0835z. Some recent runs of the high resolution convection allowing
models...including the experimental HRRR...develop storms again by
late this afternoon over southeast Nebraska and southwest Iowa. If
confidence of that happening...with heavy rain....increases then
we may need a new flash flood watch for that area. Day 1 SPC
outlook seems fine with better parameters for organized severe
storms mostly to our southwest.

.LONG TERM...(Sunday night through Thursday)
Issued at 350 AM CDT Fri May 27 2016

Pattern then turns active again early next week as 500 mb trough
moves toward our area. The GFS and ECMWF are in fair agreement...
showing a closed low forming in the northern plains. But the ECMWF
is more progressive...and prefer a solution closer to a blend. At
least for now it seems that rain chances will be lower in the
later part of the week.

&&

.AVIATION...(06Z TAFS for KOMA...KLNK...KOFK through 06Z Saturday)
Issued at 1145 PM CDT Thu May 26 2016

Wake-low-induced gusty winds ongoing at KOMA should subside within
the next couple of hours as the surface pressure gradient relaxes.
A band of mainly showers over central Nebraska should gradually
overspread the TAF sites overnight in response to the
northeastward progression of an MCV currently near KLXN. Some MVFR
ceilings may develop late tonight into early Friday on the
backside of this precipitation band. A break in the precipitation
is expected generally between 12 and 18z Friday before shower and
thunderstorm chances again increase ahead of the mid-level trough
pivoting northeast across the central Plains.

&&

.OAX Watches/Warnings/Advisories...
NE...None.
IA...None.
&&

$$

SHORT TERM...Miller
LONG TERM...Miller
AVIATION...Mead



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