Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 221709

Area Forecast Discussion
National Weather Service Aberdeen SD
1209 PM CDT MON AUG 22 2016

Issued at 1044 AM CDT MON AUG 22 2016

The current forecast for today looks good overall. No major
changes planned at this time.


.SHORT TERM...(Today through Wednesday Afternoon)
Issued at 328 AM CDT MON AUG 22 2016

Main story for today will be the hot temperatures and heightened
fire danger, especially over central SD. Very warm air aloft
continues to be pumped into the region. Stronger southerly winds
today will provide for better mixing down of these warmer temps
aloft. Highs will range from the upper 80s east to around 100
degrees over central SD. Drier air will also be in place over
western and central SD. Min RH values are forecast to fall to around
20 percent over fire weather zone 267, and it appears the pressure
gradient will be enough to keep some gusty southerly winds
maintained through the afternoon. Have therefore issued a Red Flag
warning for the far southwest CWA for this afternoon.

On Tuesday, a cold front begins marching eastward across the CWA,
ending up over the eastern counties by 00Z Wednesday. Will be
watching potential for thunderstorms along the front by late
afternoon and especially during the evening hours. Shear profiles
are a bit marginal, and moisture return along the front is a bit
late. It appears there could be some capping issues to contend with
especially if dewpoints struggle to rise during the afternoon.
Nonetheless, maintained slight chances for the afternoon then beefed
up chances after 00Z. Aside from the storm chances on Tuesday, will
have to watch fire weather once again in the post-frontal air mass.
Drier air moves in behind the front during the afternoon over
central SD, along with gusty northwest winds. RH values are forecast
to fall to around 20 percent once again west of the Missouri. May
need to consider fire weather headlines for Tuesday afternoon as

Much cooler temperatures arrive on Wednesday in the wake of the
departing cold front. Highs will drop back into the 70s, along with
breezy/gusty northwest winds and dry conditions.

.LONG TERM...(Wednesday Evening through Sunday)
Issued at 328 AM CDT MON AUG 22 2016

A broad upper trof will dominate conditions across the northern
plains initially, with cold advection at 850mb. Coldest air aloft
will be in place Thursday morning, however weak warm advection will
develop shortly thereafter. The combination of steepening mid level
lapse rates and moisture advection will result in elevated
instability Friday. We will also see favorable placement of a jet
entrance region with a Q-vector bullseye over the CWA.

With weak steering flow aloft, not much for thermal advection once
the upper wave moves east. The GFS does depict an upper wave moving
across Canada by the end of the weekend which would draw hotter air
back across the CWA but confidence at this distance in time is low.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1206 PM CDT MON AUG 22 2016

VFR conditions will prevail through the period. However, low level
wind shear is expect to develop across the eastern portions of the
area with LLWS likely at KABR, KATY and KPIR.


.ABR Watches/Warnings/Advisories...
SD...Red Flag Warning until 8 PM CDT this evening for SDZ267.



LONG TERM...Connelly
AVIATION...Scarlett is the U.S. government's official web portal to all federal, state and local government web resources and services.