Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 05/22/23

Area Forecast Discussion

National Weather Service North Platte NE

 659 PM CDT Sun May 21 2023

...00z Aviation Discussion...

.SYNOPSIS...
Issued at 401 PM CDT Sun May 21 2023

Key Messages:

- Smoke from distant wildfires will continue to affect central and
  western Nebraska through Monday.

- Temperatures at or above normal through the upcoming workweek.

- Chances for showers and thunderstorms increase from Wednesday
  onward.

&&

.SHORT TERM...(This evening through Monday night)
Issued at 401 PM CDT Sun May 21 2023

Satellite imagery shows dense smoke aloft with a blooming cumulus
field developing beneath from northeast to southwest Nebraska in
an area of weak surface convergence as a diminishing short wave
slides down the face of the large upper ridge over the western US
and approaches the region from the north. Bufkit soundings
indicate a long and skinny CAPE environment with weak flow aloft
and mid level lapse rates that are not conducive to supporting
vigorous updrafts. Expect there will be enough forcing and
instability to grow an isolated shower or thunderstorm in the
cumulus field as if drifts slightly eastward this evening into
early tonight, but do not anticipate there will be any potential
for severe weather given the anemic wind field and meager
instability profiles. WOuld not be overly surprising to see an
isolated shower burbling through tonight but by and large expect
dry conditions from Midnight onward. It will certainly look
smoky/hazy but the majority of the smoke is expected to remain
elevated through tonight. However with loss of diurnal mixing and
increasing humidity, expect there will be some fog formation that
will be amplified a bit by the smoke. Will introduce a smoke and
fog mix for several hours before and after daybreak but expect
visibilities will remain above 3SM. Expect another mild night
tonight with lows in the low to mid 50s.

With no change in airmass and an environment that continues to
lack support for vigorous updrafts, Monday looks quite similar to
today though lacking a notable, discrete short wave aloft. With
this in mind expect another chance for isolated thunderstorms
mainly Monday afternoon into early evening, along with some
lingering smoke. Highs tomorrow will be in the middle 70s to
around 80 with lows Monday night in the low to mid 50s.

.LONG TERM...(Tuesday through Sunday)
Issued at 401 PM CDT Sun May 21 2023

Ensemble guidance remains in good agreement in maintaining a warm
and rather stagnant pattern over the High Plains through the end
of next week. The axis of the large upper ridge over the western
US will gradually push to our east by Wednesday as southerly flow
on the back side of a large surface high over the eastern US sets
up a steady flow of moisture into the region. A ribbon of
precipitable water values in the 90th percentile will slowly
cross Nebraska from west to east with a weak warm front during the
latter portion of the workweek. This will bring us a good chance
of showers and thunderstorms with a diurnal bias and each day from
Wednesday onward. While there will be ample instability to fuel
convection and favorable low level shear profiles in the vicinity
of the warm front, ensemble 0-6km bulk shear values show
considerable variability though mean values remain generally at or
below 20kt and Bufkit soundings show some warm mid level capping.
Thus while a severe threat may materialize, at this point it
remains undefined. Higher confidence resides in potential for
heavy downpours given the anomalous precipitable water values and
instability. The upper ridge starts to get beaten down a bit by
next weekend as a good push of short wave energy moves across
southern Canada. This will keep showers and thunderstorms around
through Sunday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 659 PM CDT Sun May 21 2023

Smoke aloft and occasionally at the surface will impact western
and north central Nebraska through the valid period.

Isolated showers and thunderstorms have developed along a weak
boundary. This activity will diminish and end by sunset. No
shower or thunderstorms activity is forecast at the KLBF or KVTN
TAF sites.

Smoke continues to push southward out of the Dakotas
and into Nebraska. Upstream observations indicate visibilities
below 5SM across northeast WY with 8SM at KVTN. With the
expectation of thicker smoke to the north will use 6SM at KVTN
and continue until 05Z. After sunset as diurnal mixing allows
smoke to settle and humidity increases, expect a mix of fog and
smoke will develop with MVFR visibilities possible at both KLBF
and KVTN late tonight into early Monday morning. Will not mention
attm with only patchy coverage possible. Will reevaluate these
possibilities with the upcoming 06Z TAFs.

Winds outside of any shower or thunderstorm activity will
generally be light with no impact to aircraft operations. However
gusty conditions can be expected near any shower or thunderstorm
until sunset.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MBS
SHORT TERM...MBS
LONG TERM...MBS
AVIATION...Roberg