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FXUS63 KMPX 222329

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
629 PM CDT Thu Jun 22 2017

.UPDATE...For 00z Aviation discussion below


.SHORT TERM...(This evening through Friday)
Issued at 353 PM CDT Thu Jun 22 2017

Cold front was just now making it into eastern MN, and clearing 
has moved into west central and central MN behind the front. Upper
trough axis is expected to move across the area late tonight and
Friday morning, but main forcing will depart this evening. There 
is some decent fgen across the area, and radar does indeed show 
some bands of heavier precip. But the only thunder threat is 
across south central into southeast MN, and even that should end 
by early evening. 

A fairly dense band of stratucu in Manitoba and Saskatchewan had
moved into northern ND and MT, associated with the upper low now
in central Manitoba. As the low moves across northern Ontario
tonight, northwest flow will bring the clouds over our area
tomorrow morning. Thus think that a large part of central MN into
WI will see plenty of clouds tomorrow. Southwest MN might escape
some of this, but even that is doubtful. Looks like mostly cloudy
and cool conditions tomorrow, and a bit blustery, especially in
western MN, but with some peeks of sun.

.LONG TERM...(Friday night through Thursday)
Issued at 353 PM CDT Thu Jun 22 2017

Little change to the long term period.  The primary topic of 
discussion continues to be the longwave trough taking hold over 
eastern North America keeping us in cool northwesterly flow this 
weekend, with bouts of showers and possibly a few weak 

By tomorrow evening, the cooler airmass will be in place with the 
main jet to our south.  A shortwave trough will be in the process of 
diving south across Canada, headed for our area by Saturday.  Given 
the PV advection and steepening lapse rates due to upper level 
height falls and diurnal heating, we should see showers develop, 
with weak thunderstorms possible during the afternoon.  Average 
highs are now in the low 80s, but the weekend will be held in the 
mid and upper 60s across the region.  

Nothing really changes Sunday, more perturbations in the flow will 
move through and we again have chances for showers and weak storms 
under cyclonic flow aloft. 

The western CONUS ridge looks to progress east by midweek, pushing 
the trough well east of us and bringing warmer air back to the 
region. Temperatures look to climb back to normal for late June 
by the middle of the week.


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 630 PM CDT Thu Jun 22 2017

Showers will affect KEAU at the start of the period, and then
clouds will scatter out area-wide tonight. Cyclonic flow will 
bring in a dense deck of stratocu clouds for Friday, with BKN-OVC 
cigs around 5000 feet, and potentially a lower deck around 
2500ft. Northwest winds will also become gusty on Thursday 
morning, generally around 15-17kts with gusts to between 22-25kts.

Benign conditions overnight and then bkn-ovc low-end VFR deck
moves in for Thursday, with sct MVFR clouds around 2500 ft as
well. Gusts to around 25 knots develop by late morning.


Sat...VFR. Chc MVFR with p.m. -TSRA. Winds NW 15g25kts.
Sun...VFR. Chc MVFR with p.m. -TSRA. Winds NW 10kts.
Mon...VFR. Winds NW 5-10 kts.




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