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Area forecast discussion 
National Weather Service Omaha/valley NE
256 am CDT Friday Aug 1 2014

Short term...(today through sunday)
issued at 255 am CDT Friday Aug 1 2014

Short term challenge is when/if to include small precipitation chances
through this upcoming weekend.

Northwesterly upper flow over middle/lower MO valley will persist
through Sunday...although western U.S. Upper ridge is forecast to
build a little eastward bringing slightly increasing upper heights to
the forecast area. With moisture on modest side...it would appear any precipitation
chance would be small and coverage likely not very widespread.
Timing of any embedded short wave energy probably a major player
but hard to time and model quantitative precipitation forecast placement was not very uniform
among themselves. That said...departing subtle wave over southeastern
zones this morning will leave a weak boundary across that area
this afternoon which could aid in some regeneration with heating and a
slight chance was mentioned there. Additional thunderstorms could develop near
or northwest of northwestern zones late this afternoon per upstream wave in overnight
water vapor imagery...with any of this precipitation drifting southeast in upper
flow. Will also include morning slight chance probability of precipitation far southeastern zones as
weak activity had continued to reform upstream through 0730z.

As upper ridge begins shifting eastward...an ill-defined warm front
could also begin drifting east through forecast area in Sat-sun period. Besides
bringing a little warmer temperatures...weak boundary could also
bring additional small thunderstorm chances to the forecast area. For now limited
slight chance probability of precipitation to western zone Sat afternoon and then central/north Sat evening.
Sunday was left dry for now...but that could change if NAM/European model (ecmwf)
would remain consistent in some their generation of precipitation near
this ill-defined warm front per both or along a trailing weak
wind shift per NAM.

Kept temperatures mostly in the 80s today and Saturday before some
90s...mainly lower at this time...begin spreading eastward across the
area. Slightly higher dewpoints and warmer days should begin to end
string of 50s seen for overnight lows most areas...although the
normally cooler locals could still see some upper 50s yet Sat am.

Long term...(sunday night through thursday)
issued at 255 am CDT Friday Aug 1 2014

Extended begins warm and probably mostly dry as upper ridge should
have shifted over much of the forecast area by Monday. After that ridge was
advertised to begin flattening as short wave energy ejects eastward
across plains. This should bring an increasing precipitation
chances to forecast area...generally centered on the Wednesday time frame.
For the sake of continuity and lack of confidence...left Sunday
night through Monday night dry. Small chances were seen north on
Tuesday as upper heights begin falling allowing weak boundary into
that region...with modest chance probability of precipitation then overspreading forecast area Tuesday
night north...all areas Wednesday and south Wednesday night. Small probability of precipitation were
lingered south on Thursday.

More 90s seen likely Monday and central/S on Tuesday before readings
cool back into the 80s as clouds/precip/front push across the forecast area.

&&

Aviation...(06z tafs for kofk...klnk and koma.)
Issued at 1120 PM CDT Thursday Jul 31 2014

Still expect some isolated to widely scattered rain showers and thunderstorms and rain...but the chance
of thunder at any of the taf sites seems small. Did keep tempo
groups for koma and klnk early Friday morning with -shra but did
not mention a visibility restriction. Ceilings will be mainly above 4000
feet but MVFR or lower ceilings and visibilities may briefly occur in any
thunderstorms and rain. Winds will generally be light through the period. Will
amend as needed.



&&

Oax watches/warnings/advisories...
NE...none.
Iowa...none.
&&

$$

Short term...chermok
long term...chermok
aviation...Miller

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