Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 270958 CCA
AFDABR

Area Forecast Discussion...CORRECTED
National Weather Service Aberdeen SD
458 AM CDT Tue Jun 27 2017

.SHORT TERM...(Today through Thursday Afternoon)
Issued at 417 AM CDT Tue Jun 27 2017

First off, we will see strong southerly winds today as a 16-18mb
pressure gradient develops across the Dakotas. Additionally,
pressure falls of 8-9mb in 6 hours are noted across the area. This
will push us close to Advisory level winds, with sustained winds
around 30mph, though gusts will probably fall shy of 45mph except
for all but the more exposed areas. This is also responsible for
high fire danger conditions today.

These strong winds proceed a front and upper wave, and will draw
somewhat higher humidity into the region - with a narrow ribbon of
850mb dewpoints increasing to +12 to +14C by 00Z - which translates
into dewpoints in the upper 50s to low 60s Fahrenheit. 700mb
temperatures increase to +10 to +12C which will cap the atmosphere
for today, though there may be some weak, elevated convection
through the afternoon, which is depicted in a handful of CAMs. As
the cold front moves into the western CWA and towards the Missouri
valley between 00 and 03Z it will be the focus for surface based
convection, with the core of 700mb warm air moving off to the east.
Low level turning is evident in NAM BUFKIT profiles, but winds aloft
are not very strong, and 0-6kt shear around 50kts is probably
dominated by this strong low level flow. CAPE ranges between 1500-
3000J/KG so the threat for supercells and tornadoes exists, although
LCL of 4kft initially is a tad high in my taste. CAMS generally
support the transition of storms east across the CWA between
02-08Z. During this time, a low level jet with 1/2km winds of
40-50kts will develop. This may enhance low level turning ahead of
the front before storms transition to elevated convection with a
stronger wind/hail threat.


.LONG TERM...(Thursday Evening through Monday)
Issued at 417 AM CDT Tue Jun 27 2017

An upper level trough will be over the central part of the country
at the beginning of the extended period, with a series of shortwaves
set to track across the region Thursday night through Saturday
before the trough exits to the east and northwest flow becomes
dominant.

At the surface, broad weak low pressure will be over the Northern
Plains early in the period. With the upper shortwaves moving through
during this time, may see some shower and thunderstorm activity
Thursday night and Friday before high pressure settles in over the
region, bringing dry conditions back for the early part of the
weekend. Another low pressure system looks to track somewhere across
the central plains region on Sunday and Monday, bringing unsettled
conditions and precipitation chances back to the area.

Below normal temperatures will be the rule early on, with highs in
the 70s Friday and Saturday. Will then see a gradual warming trend
with highs back up in the 80s Sunday and Monday. Overnight lows will
be mainly in the 50s.


&&

.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1228 AM CDT Tue Jun 27 2017

VFR conditions are expected through most of the period. Showers
and thunderstorms are possible Tuesday evening and overnight. Some
of the storms may be strong to severe, with gusty winds and large
hail being the main threats.


&&

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

$$

SHORT TERM...Connelly
LONG TERM...Parkin
AVIATION...Parkin



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