Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 281718 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1218 PM CDT Fri Jul 28 2017

.UPDATE...
Issued at 1013 AM CDT Fri Jul 28 2017

Made a few hourly tweaks to the pop grids to scale back the precip
mention through early afternoon. Light shower activity is very
isolated this morning and will continue to be so through the day,
if it holds together.

&&

.SHORT TERM...(Today through Sunday Afternoon)
Issued at 330 AM CDT Fri Jul 28 2017

Not much overall change to the forecast at large. We see scattered
elevated weak showers across mainly central South Dakota this
morning associated with a weak wave tucked under an upper ridge,
with surface high pressure to the east providing a fairly dry
subcloud layer. Thus, don`t anticipate more than a few hundreds for
anyone out there this morning.

The weak mid level system will slowly migrate southeast across the
area today. In the low levels, the gradient will increase across the
state, with around 10mb across the state and mixed winds in the low
20kts range. As for moisture, convection looks more favorable across
western South Dakota, with the remnants drifting into western
counties before dissipating, otherwise upper flow looks unfavorable
for convection.

GFS/NAM BUFKIT soundings are unstable with 1000-1500 j/kg CAPE
Saturday afternoon thanks to southerly flow increasing low level
humidity. Mid level temperatures are only around +6 to +8C, so
introduced some low pops to cover diabatically driving convection.
There is a 90kt jet overhead, but flow beneath that is rather weak
and supportive of moistly pulse type storms which will limit
coverage.  More coverage is possible overnight with a mid level
trough passing across the northeast part of the state, aided by the
right entrance region. Guidance coverage is spotty in coverage, with
only a weak low level jet.

.LONG TERM...(Sunday Evening through Thursday)
Issued at 330 AM CDT Fri Jul 28 2017

An upper level ridge will remain over the western part of the
country through the long term period, with a few shortwaves moving
through, the most significant on Tuesday night. At the surface, the
region will be between high pressure to the east and low pressure
over the Rockies at the beginning of the period. A frontal boundary
will track across the area Tuesday afternoon and Tuesday night,
becoming the focus for showers and thunderstorms. There will be some
instability around, but little in the way of shear, so don`t expect
anything to be severe at this time. High pressure then settles in
over the region and looks to remain dominant through the end of the
period.

Temperatures will be near to slightly above normal, with highs
ranging from the mid 80s east to the lower 90s west each day.
Overnight lows will be in the lower to mid 60s.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 1217 PM CDT Fri Jul 28 2017

VFR conditions are expected through the period.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

UPDATE...Wise
SHORT TERM...Connelly
LONG TERM...Parkin
AVIATION...Wise



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