Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 kgid 210809 

Area forecast discussion
National Weather Service Hastings NE
309 am CDT sun Jul 21 2019

Short term...(today and tonight)
issued at 231 am CDT sun Jul 21 2019

In the immediate short term/predawn hours, the surface cold front
had pushed south of our cwa and was oriented from southwest to
northeast Kansas as of 07z. Cooler air with temps in the 60s were
advecting south behind the boundary from northern neb. Early night
convection initiated to our west across eastern Wyoming/co/western Kansas
and the western complex of storms has been working eastward
during the predawn hours, and additional new development has
occurred along/north of the elevated frontal boundary across
central neb.

The greater instability resides along the surface front to our
south before daybreak, however elevated instability is still
decent around 2500 j/kg along the mid level frontal zone early this
morning. Shear parameters remain more marginal at 25-30kts...but
a few strong to marginally severe storms remain possible primarily
into first part of the day. And as has been mentioned for the
last couple of days, the storms will be capable of producing
locally heavy rainfall as precipitable water values average around
two inches. We have some forecast rain amounts potentially
topping an inch primarily in the Platte and Loup basins and will
need to monitor where heavier rain bands set up today.

The hrrr model is handling the timing/coverage of the convection
fairly well early this morning and keeps a fair amount of precip
around for a good portion of the day. Daytime temps will be
quite a bit cooler than recent days in the Post frontal airmass
with readings ultimately dependent upon clouds and how long precip
lingers. Aftn highs in the low/mid 70s should be common across
south central neb with some 80s possible in north central Kansas.

The mesoscale complex is expected to depart to the southeast this
evening with any remnant convection winding down pretty quickly.
Surface high pressure building south from the Dakotas tonight will
reinforce the cooler airmass and noticeably less humid air will
filter south with dps in the 50s. Temps are set to average in the
50s for lows which we've seen very little of yet this July.

Long term...(monday through saturday)
issued at 231 am CDT sun Jul 21 2019

The extended forecast is still looking pretty quiet weatherwise. The
dry, cooler airmass remains across our region for the first part of
the week (mon/tues) in between a western upper ridge over The
Rockies and an eastern trough from Quebec through the Ohio Valley.
For those wanting to give air conditioners a break...daytime temps
should average in the 70s, with readings at night dropping into
the 50s.

For the middle/latter part of the week, temperatures will return to
the 80s for highs in a moderating more seasonal airmass as the
western upper ridge expands east but dampens due to a series of
shortwaves translating across Canada and the northern plains
states. Precip chances remain pretty minimal for the upcoming
workweek and into the first part of the weekend with just small
chances in the forecast thurs/Friday.


Aviation...(for the 06z kgri/kear tafs through 06z monday)
issued at 1205 am CDT sun Jul 21 2019

MVFR ceilings will drop to IFR early this morning. Vcts, decided
to push back timing in the tafs for thunderstorms in the vicinity as model guidance is
currently showing it around the 12z time frame. A few showers are
starting to form on radar so will keep on it and will amend if ts
looking to impact the taf sites. Winds will generally be
northeasterly through the period. Expect occasional gusts to 18-20kts


Gid watches/warnings/advisories...


National Weather Service Glossary of Abbreviations