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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
554 am CDT Sat Aug 29 2015

Updated for 12z aviation discussion...
issued at 548 am CDT Sat Aug 29 2015


Short term...(today and tonight)
issued at 345 am CDT Sat Aug 29 2015

Expect a dry forecast throughout the short term with temperatures
continuing to increase from the previous days readings. At first
glance the area of showers and thunderstorms north of Duluth heading
south could pose a threat of rain to the Minnesota/WI counties along and
east of I-35...but parent wave driving the storms will race to the
east...and although the hires models are struggling with the current
placement of convection...they continue to weaken it between 09- will hold true to the dry forecast.

The main challenge in this time period was the handling of
fog/stratus through the early morning hours. Low level moisture was
inching up from the south...with sub-1000ft ceilings. The last
couple runs of the hopwrf cloud probability show this encroaching
upon Eau Claire / Twin Cities this morning before dissipating later tried to reflect that in the cloud grids.

Later today southwesterly flow and warm air advection will bring
afternoon highs into the low to middle 80s across far western Minnesota...with
upper 70s in eastern Minnesota and western WI. As we finish out the month
of August...shorter days and clear calm nights should favor
radiational fog across the reintroduced patchy fog for
late tonight into Sunday morning.

Long term...(sunday through friday)
issued at 345 am CDT Sat Aug 29 2015

Upper level ridging will be overhead at the start of the long
term with 24 degree c air at 850mb pushing into west central and
northwest Minnesota Sunday afternoon. Middle-down from 900 mb yields
highs around 90 for Madison and Morris and this GOES along well
with observed highs in the western Dakotas Friday afternoon with
similar 850mb temperatures. Therefore...blended in the mix-down
with raw blend and the current forecast. This raised highs some
from the metropolitan area on north through St cloud and Mora with
middle 80s forecast. The coolest highs on Sunday stretch from
Albert Lea to Eau Claire with around 80 to the lower 80s.

The ridge will move east of US on Monday with a weak cool front
moving across the Dakotas. This boundary will move into Minnesota
Monday night and Tuesday. There remains a small threat for showers
and thunderstorms along the front with the best chances over the
northeast portion of the state at the nose of the low level
moisture transport. We may struggle in our forecast area to see much with a
rather pronounced warm layer between 800-700 mb.

Much of the remainder of the workweek is dry along with highs in
the middle 80s. However...there are some caveats. The boundary
across the area on Tuesday will stall and begin to move back north
as a warm front on Wednesday. While this is occurring...a short
wave will move our way in the southwest flow aloft...passing
across the forecast area Wednesday afternoon and night. This will offer
another opportunity for some showers and thunderstorms across
eastern areas of the forecast area. Another chance of showers and
thunderstorms is indicated on Friday as another weak front
approaches from the Dakotas.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 548 am CDT Sat Aug 29 2015

VFR conditions at the northwest sites...but fairly confident that
the low clouds to the south are going to persist through the
morning at Keau. The northern portion should creep into msp as
well...but for now have it south of krnh. Winds will be light with
a southerly component. There is some potential for fog again
tonight...but southerly breeze should limit the possibility of

challenging forecast for msp. The low clouds are inching
northward...and should affect kmsp...but it will be a very close
call. Have high confidence that bases will be below its
pretty much all or nothing for the first few hours of the taf
period. Once the clouds are gone expect VFR conditions throughout.

/Outlook for kmsp/
sun...VFR. Winds S at 10g15kt
Monday...VFR. Winds S at 5-10kt
Tuesday...VFR. Winds S at 5-10kt


Mpx watches/warnings/advisories...


Short term...jrb
long term...rah

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